Special Issue "Phenolic Profiling and Antioxidant Capacity in Plants"

A special issue of Antioxidants (ISSN 2076-3921). This special issue belongs to the section "Natural and Synthetic Antioxidants".

Deadline for manuscript submissions: 31 January 2020.

Special Issue Editors

Prof. Dr. Luigi Lucini
E-Mail Website
Guest Editor
Universita Cattolica del Sacro Cuore, Department for Sustainable Food Process, Milan, Italy
Interests: food metabolomics and functional foods; pigmented flours; bound phenolics; bioaccessibility of polyphenols
Assoc. Prof. Dr. Andrei Mocan
E-Mail
Co-Guest Editor
Department of Pharmaceutical Botany, Iuliu Hațieganu University of Medicine and Pharmacy, 23 Ghe. Marinescu Street, Cluj-Napoca 400337, Romania
Interests: pharmaceutical biology (botany); valorization of traditional medicinal and edible plants and fungi; extraction optimization of bioactive compounds from plant materials; experimental design applied to extraction and process optimization; bioactivity and chemical characterization of natural products, development of new nutraceuticals based on medicinal plants and fungi, natural products as enzyme inhibitors
Special Issues and Collections in MDPI journals
Dr. Gabriele Rocchetti
E-Mail Website
Co-Guest Editor
Universita Cattolica del Sacro Cuore, Department for Sustainable Food Process, Milan, Italy

Special Issue Information

Dear Colleagues,

The interest in foods of plant origin as a source of polyphenols originated in the 1990s and, to date, continue to receive a great deal of attention. The recent advances in analytical approaches, -omic sciences and biotechnology are offering new and interesting insights into the characterization, comprehensive profiling and biological activity of phenolics. In parallel, the recent knowledge on existing in vitro antioxidant assays suggest that further research is still necessary, to move towards measures representative of in vivo conditions.

Contributions to this Special Issue may cover all research aspects related to the characterization of phenolic compounds and their antioxidant capacity, including (but not limited to) methods for their extraction, purification, characterization and quantification; the elucidation of their mechanisms of action with focus on antioxidant capacity; improved methods for assessing antioxidant capacity (cell-based assays are encouraged); and the effect of both pre- and post-harvest factors on phenolic profiles in plants.

Prof. Dr. Luigi Lucini
Dr. Andrei Mocan
Dr. Gabriele Rocchetti
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Antioxidants is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1200 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Polyphenols
  • Free and bound phenolics
  • Flavonoids
  • Hydroxycinnamics
  • Lignans
  • Antioxidant capacity
  • Radical scavenging

Published Papers (36 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

Open AccessArticle
Chemical Profiling and Biological Properties of Extracts from Different Parts of Colchicum Szovitsii Subsp. Szovitsii
Antioxidants 2019, 8(12), 632; https://doi.org/10.3390/antiox8120632 - 11 Dec 2019
Abstract
Like other members of the Colchicum genus, C. szovitsii subsp. szovitsii is also of medicinal importance in Turkish traditional medicine. However, its biological properties have not been fully investigated. Herein, we focused on the evaluation of the in vitro antioxidant and enzyme [...] Read more.
Like other members of the Colchicum genus, C. szovitsii subsp. szovitsii is also of medicinal importance in Turkish traditional medicine. However, its biological properties have not been fully investigated. Herein, we focused on the evaluation of the in vitro antioxidant and enzyme inhibitory effects of flower, root and leaf extracts, obtained using different extraction methods. In addition, a comprehensive (poly)-phenolic and alkaloid profiling of the different extracts was undertaken. In this regard, ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) allowed us to putatively annotate 195 polyphenols and 87 alkaloids. The most abundant polyphenols were flavonoids (83 compounds), whilst colchicine and 2-demethylcolchicine were some of the most widespread alkaloids in each extract analyzed. However, our findings showed that C. szovitsii leaf extracts were a superior source of both total polyphenols and total alkaloids (being, on average 24.00 and 2.50 mg/g, respectively). Overall, methanolic leaf extracts showed the highest (p < 0.05) ferric reducing antioxidant power (FRAP) reducing power (on average 109.52 mgTE/g) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging (on average 90.98 mgTE/g). Interestingly, each C. szovitsii methanolic extract was more active than the water extracts when considering enzymatic inhibition such as against tyrosinase, glucosidase, and acetylcholinesterase (AChE). Strong correlations (p < 0.01) were also observed between polyphenols/alkaloids and the biological activities determined. Multivariate statistics based on supervised orthogonal projections to latent structures discriminant analysis (OPLS-DA) allowed for the detection of those compounds most affected by the different extraction methods. Therefore, this is the first detailed evidence showing that C. szovitsii subsp. szovitsii might provide beneficial effects against oxidative stress and the associated chronic diseases. Nevertheless, the detailed mechanisms of action need to be further investigated. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
Hydroponically Grown Sanguisorba minor Scop.: Effects of Cut and Storage on Fresh-Cut Produce
Antioxidants 2019, 8(12), 631; https://doi.org/10.3390/antiox8120631 - 09 Dec 2019
Abstract
Wild edible plants have been used in cooking since ancient times. Recently, their value has improved as a result of the scientific evidence for their nutraceutical properties. Sanguisorba minor Scop. (salad burnet) plants were hydroponically grown and two consecutive cuts took place at [...] Read more.
Wild edible plants have been used in cooking since ancient times. Recently, their value has improved as a result of the scientific evidence for their nutraceutical properties. Sanguisorba minor Scop. (salad burnet) plants were hydroponically grown and two consecutive cuts took place at 15 (C1) and 30 (C2) days after sowing. An untargeted metabolomics approach was utilized to fingerprint phenolics and other health-related compounds in this species; this approach revealed the different effects of the two cuts on the plant. S. minor showed a different and complex secondary metabolite profile, which was influenced by the cut. In fact, flavonoids increased in leaves obtained from C2, especially flavones. However, other secondary metabolites were downregulated in leaves from C2 compared to those detected in leaves from C1, as evidenced by the combination of the variable important in projections (VIP score > 1.3) and the fold-change (FC > 2). The storage of S. minor leaves for 15 days as fresh-cut products did not induce significant changes in the phenolic content and antioxidant capacity, which indicates that the nutraceutical value was maintained. The only difference evidenced during storage was that leaves obtained from C2 showed a lower constitutive content of nutraceutical compounds than leaves obtained from C1; except for chlorophylls and carotenoids. In conclusion, the cut was the main influence on the modulation of secondary metabolites in leaves, and the effects were independent of storage. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
Potential of Smoke-Water and One of Its Active Compounds (karrikinolide, KAR1) on the Phytochemical and Antioxidant Activity of Eucomis autumnalis
Antioxidants 2019, 8(12), 611; https://doi.org/10.3390/antiox8120611 - 03 Dec 2019
Abstract
Eucomis autumnalis (Mill.) Chitt. subspecies autumnalis is a popular African plant that is susceptible to population decline because the bulbs are widely utilized for diverse medicinal purposes. As a result, approaches to ensure the sustainability of the plants are essential. In the current [...] Read more.
Eucomis autumnalis (Mill.) Chitt. subspecies autumnalis is a popular African plant that is susceptible to population decline because the bulbs are widely utilized for diverse medicinal purposes. As a result, approaches to ensure the sustainability of the plants are essential. In the current study, the influence of smoke-water (SW) and karrikinolide (KAR1 isolated from SW extract) on the phytochemicals and antioxidant activity of in vitro and greenhouse-acclimatized Eucomis autumnalis subspecies autumnalis were evaluated. Leaf explants were cultured on Murashige and Skoog (MS) media supplemented with SW (1:500, 1:1000 and 1:1500 v/v dilutions) or KAR1 (10−7, 10−8 and 10−9 M) and grown for ten weeks. In vitro regenerants were subsequently acclimatized in the greenhouse for four months. Bioactive phytochemicals in different treatments were analyzed using ultra-high performance liquid chromatography (UHPLC-MS/MS), while antioxidant potential was evaluated using two chemical tests namely: DPPH and the β-carotene model. Smoke-water and KAR1 generally influenced the quantity and types of phytochemicals in in vitro regenerants and acclimatized plants. In addition to eucomic acid, 15 phenolic acids and flavonoids were quantified; however, some were specific to either the in vitro regenerants or greenhouse-acclimatized plants. The majority of the phenolic acids and flavonoids were generally higher in in vitro regenerants than in acclimatized plants. Evidence from the chemical tests indicated an increase in antioxidant activity of SW and KAR1-treated regenerants and acclimatized plants. Overall, these findings unravel the value of SW and KAR1 as potential elicitors for bioactive phytochemicals with therapeutic activity in plants facilitated via in vitro culture systems. In addition, it affords an efficient means to ensure the sustainability of the investigated plant. Nevertheless, further studies focusing on the use of other types of antioxidant test systems (including in vivo model) and the carry-over effect of the application of SW and KAR1 for a longer duration will be pertinent. In addition, the safety of the resultant plant extracts and their pharmacological efficacy in clinical relevance systems is required. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
Free and Bound Phenolics of Buckwheat Varieties: HPLC Characterization, Antioxidant Activity, and Inhibitory Potency towards α-Glucosidase with Molecular Docking Analysis
Antioxidants 2019, 8(12), 606; https://doi.org/10.3390/antiox8120606 - 29 Nov 2019
Abstract
Free and bound phenolic fractions from six buckwheat varieties were investigated for their compositions, antioxidant activities, and inhibitory effects on α-glucosidase. The results showed that different buckwheat varieties have significant differences in phenolic/flavonoid contents, and these contents were found in higher quantities in [...] Read more.
Free and bound phenolic fractions from six buckwheat varieties were investigated for their compositions, antioxidant activities, and inhibitory effects on α-glucosidase. The results showed that different buckwheat varieties have significant differences in phenolic/flavonoid contents, and these contents were found in higher quantities in free form than in bound form. HPLC results revealed that rutin, quercetin, and kaempferol-3-O-rutinoside were the most abundant components in free and bound forms, whereas dihydromyricetin was found only in the bound form. Free phenolics showed higher antioxidant activities of DPPH, ABTS·+, OH, and FRAP than those of bound phenolics. Strong inhibitory effects against α-glucosidase by the free/bound phenolic fractions were found in all buckwheat varieties, and free phenolics showed stronger α-glucosidase inhibition than that of the corresponding bound phenolics. More importantly, the main phenolic compounds observed in the buckwheat varieties were subjected to molecular docking analysis to provide insight into their interactions with α-glucosidase. The contributions by individual phenolics to the observed variation was analysed by Pearson correlation coefficient analysis and principal component analysis. The present study provides a comprehensive comparison for the phenolic fractions of buckwheat varieties and identify the main contributors to antioxidant and α-glucosidase inhibitory activity. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Graphical abstract

Open AccessArticle
UHPLC–Q/Orbitrap/MS/MS Fingerprinting, Free Radical Scavenging, and Antimicrobial Activity of Tessaria absinthiodes (Hook. & Arn.) DC. (Asteraceae) Lyophilized Decoction from Argentina and Chile
Antioxidants 2019, 8(12), 593; https://doi.org/10.3390/antiox8120593 - 28 Nov 2019
Abstract
The decoction of Tessaria absinthioides is used in traditional medicine of South America as hypocholesterolemic, balsamic, and expectorant; but it is also useful for the prevention of hepatitis, renal insufficiency, and diabetes, and is used as digestive. A lyophilized decoction from the aerial [...] Read more.
The decoction of Tessaria absinthioides is used in traditional medicine of South America as hypocholesterolemic, balsamic, and expectorant; but it is also useful for the prevention of hepatitis, renal insufficiency, and diabetes, and is used as digestive. A lyophilized decoction from the aerial parts of this plant (TLD) collected in San Juan (TLDSJ) and Mendoza (TLDM) provinces (Argentina) and one collection from Antofagasta, Chile (TLDCH) were characterized regarding antioxidant and antibacterial activities, phenolics and flavonoids content, and ultrahigh resolution liquid chromatography Orbitrap MS analysis UHPLC–PDA–OT-MS/MS metabolite profiling. The antioxidant properties were carried out "in vitro" using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and trolox equivalent antioxidant activity (TEAC) methods, ferric-reducing antioxidant power (FRAP), and lipoperoxidation in erythrocytes (LP). The antibacterial activity was evaluated following the Clinical and Laboratory Standards Institute (CLSI) rules. TLDSJ, TLDM, and TLDCH displayed a strong DPPH scavenging activity (EC50 = 42, 41.6, and 43 µg/mL, respectively) and inhibition of lipoperoxidation in erythrocytes (86–88% at 250 µg TLD/mL), while a less effect in the FRAP and TEACantioxidant assays was found. Additionally, the decoctions showed a content of phenolics compounds of 94 mg gallic acid equivalents (GAE)/g, 185 GAE/g, and 64 GAE/g, for TLDSJ, TLDM, and TLDCH samples, respectively. Regarding the flavonoid content, the Chilean sample was highlighted with 19 mg quercetin equivalents (QE)/g. In this work, several phenolic compounds, including sesquiterpenes, flavonoids, and phenolic acids, were rapidly identified in TLDSJ, TLDM, and TLDCH extracts by means UHPLC–PDA–OT-MS/MS for the first time, which gave a first scientific support to consider this medicinal decoction from both countries as a valuable source of metabolites with antioxidant effects, some with outstanding potential to improve human health. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
Polyphenolic Composition and Hypotensive Effects of Parastrephia quadrangularis (Meyen) Cabrera in Rat
Antioxidants 2019, 8(12), 591; https://doi.org/10.3390/antiox8120591 - 27 Nov 2019
Abstract
Parastrephia quadrangularis (Pq), commonly called “Tola”, is widely used in folk medicine in the Andes, including for altitude sickness. In this study, polyphenolic composition was determined, and hypotensive effects were measured; the ethnopharmacological use as hypotensive was related to the presence of phenolic [...] Read more.
Parastrephia quadrangularis (Pq), commonly called “Tola”, is widely used in folk medicine in the Andes, including for altitude sickness. In this study, polyphenolic composition was determined, and hypotensive effects were measured; the ethnopharmacological use as hypotensive was related to the presence of phenolic compounds. For this purpose, male Sprague-Dawley rats (6 to 8 weeks of age, 160 to 190 g) were fed Pq extract (10 to 40 mg/kg) for 10 days through gavage. Blood pressures and heart rate were significantly (p < 0.01) reduced in normotensive rats receiving Pq extract (40 mg/kg body weight). Pq extract induced a negative inotropic effect, and endothelium-dependent vasodilation mediated by nitric oxide (NO). Furthermore, preincubation with Pq extract significantly decreased the cytosolic calcium on vascular smooth muscle cells A7r5 in response to L-phenylephrine (PE). Seven metabolites were isolated from the Pq extract, but three flavonoids (10−4 M) showed similar vasodilation to the extract in intact rat aorta as follows: 5,3′,4′-trihydroxy-7-methoxyflavanone (2); 3,5,4′-trihydroxy-7,8,3′-trimethoxyflavone (6); and 5,4′-dihydroxy-3,7,8,3′-tetramethoxyflavone (7). The Pq extract and compounds 2 and 7 significantly (p < 0.05) reduced the contraction to Bay K8644 (10 nM, an agonist of CaV1.2 channels). Administration of Pq decreased cardiac contractility and increased endothelium-dependent and -independent vasodilation. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Graphical abstract

Open AccessArticle
The Influence of In Vitro Gastrointestinal Digestion on the Chemical Composition and Antioxidant and Enzyme Inhibitory Capacities of Carob Liqueurs Obtained with Different Elaboration Techniques
Antioxidants 2019, 8(11), 563; https://doi.org/10.3390/antiox8110563 - 16 Nov 2019
Abstract
Carob liqueur is a traditional Mediterranean alcoholic beverage obtained via a wide range of production techniques contributing to the different organoleptic attributes of the final product. The aim of this research was to evaluate the stability of the chemical composition and biological capacities [...] Read more.
Carob liqueur is a traditional Mediterranean alcoholic beverage obtained via a wide range of production techniques contributing to the different organoleptic attributes of the final product. The aim of this research was to evaluate the stability of the chemical composition and biological capacities (antioxidant and enzyme inhibition) under in vitro simulated gastrointestinal digestion of liqueurs prepared by flavouring the fig spirit with carob pulp by maceration, distillation, percolation, or aqueous and hydro-alcoholic infusions. For this purpose, the phenolic and furanic compositions, the total phenolic (TPC) and flavonoid (TFC) contents, antioxidant capacity (AC), and enzyme inhibitory potential against acethylcholinesterase, tyrosinase, α-glucosidase and α-amylase enzymes were evaluated. The content of gallic acid decreased after gastrointestinal digestion, while TPC, TFC, and AC significantly increased after each digestion phase. Overall, no significantly different enzyme inhibitions (p < 0.05) were observed among digested liqueurs, with moderate inhibition against acethylcholinesterase and tyrosinase (enzymes related with neurodegenerative diseases), and potent and low inhibitory capacities for α-glucosidase and α-amylase, respectively (ideal conditions employed in antidiabetic therapy). The study indicates that hydro-alcoholic infusion and maceration were the most appropriate methods to obtain liqueurs with higher values of the aforementioned parameters and safe levels of toxic furanics. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
From the Field to the Pot: Phytochemical and Functional Analyses of Calendula officinalis L. Flower for Incorporation in an Organic Yogurt
Antioxidants 2019, 8(11), 559; https://doi.org/10.3390/antiox8110559 - 15 Nov 2019
Cited by 1
Abstract
Edible flowers have been used as ingredients because of their biological activities, taste, and overall appearance. This research was aimed to characterize the chemical composition and in vitro antioxidant activity of the marigold flower (Calendula officinalis L.) extracted with different proportions of [...] Read more.
Edible flowers have been used as ingredients because of their biological activities, taste, and overall appearance. This research was aimed to characterize the chemical composition and in vitro antioxidant activity of the marigold flower (Calendula officinalis L.) extracted with different proportions of water and ethyl alcohol, and the lyophilized extract with higher content of antioxidant compounds was incorporated into an organic yogurt. Results showed that the hydroalcoholic extract (50:50 v/v) presented the highest total phenolic content (TPC), flavonoids, and antioxidant activity (ferric reducing antioxidant power (FRAP), total reducing capacity (TRC), and Cu2+/Fe2+ chelating ability). Phenolic acids and flavonoids were quantified in the extract by LC-DAD, while 19 compounds were tentatively identified by ESI-MS/MS. The lyophilized marigold extract (LME) also inhibited 12% of Wistar rat’s brain lipid oxidation in vitro, inhibited α-amylase, and α-glucosidase activities, but showed no cytotoxicity towards cancerous cells (HCT8 and A549). However, marigold flower extract protected human erythrocytes against mechanical stress. When added into an organic yogurt model (0 to 1.5%), LME increased TPC and antioxidant activity (2,2-diphenyl-1-picrylhydrazyl (DPPH) and TRC), and the sensory analysis showed that the organic yogurt had an acceptance of 80.4%. Our results show that the use of LME may be a technological strategy to increase the content of bioactive compounds in yogurts. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Graphical abstract

Open AccessArticle
Influence of Cooking and Ingredients on the Antioxidant Activity, Phenolic Content and Volatile Profile of Different Variants of the Mediterranean Typical Tomato Sofrito
Antioxidants 2019, 8(11), 551; https://doi.org/10.3390/antiox8110551 - 14 Nov 2019
Abstract
In this study, six different sofrito formulations were compared with the raw recipe for total phenolic content (TPC), antioxidant activity tested by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric-reducing antioxidant power (FRAP) and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) methods. The volatile profile was also obtained by [...] Read more.
In this study, six different sofrito formulations were compared with the raw recipe for total phenolic content (TPC), antioxidant activity tested by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric-reducing antioxidant power (FRAP) and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) methods. The volatile profile was also obtained by the headspace solid-phase microextraction-gas chromatography mass spectrometry (HS-SPME-GC–MS) procedure. The cooking process and the addition of herbs, and garlic improved the final content of antioxidant compounds compared to the basic recipe and the raw ingredients. The total volatile content was higher in the samples that contained rosemary and thymus. Some of the volatiles had proven antioxidant properties and for that reason the sofrito with rosemary with the higher volatile content was also the one with the higher antioxidant capacity and TPC. In conclusion, as well as the processing technique, the addition of selected typical Mediterranean herbs apart from given flavour can contribute to improving the nutritional antioxidant profile of dishes and be used as a natural method to increase the shelf-life of preparation. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Graphical abstract

Open AccessArticle
Phytochemical Characterization of Commercial Processed Blueberry, Blackberry, Blackcurrant, Cranberry, and Raspberry and Their Antioxidant Activity
Antioxidants 2019, 8(11), 540; https://doi.org/10.3390/antiox8110540 - 10 Nov 2019
Abstract
Being delicious and containing strong disease-fighting agents, berries represent an increasing proportion of fruits consumed nowadays in our diet. However, berries are highly perishable as fresh and, therefore, they are usually processed into various products to extend their shelf-life and availability throughout the [...] Read more.
Being delicious and containing strong disease-fighting agents, berries represent an increasing proportion of fruits consumed nowadays in our diet. However, berries are highly perishable as fresh and, therefore, they are usually processed into various products to extend their shelf-life and availability throughout the year. Among the fruit-containing products, jam is one of the most common due to its nourishing properties, its low production costs, and its accessibility for a lengthy period. Rather than home preparation, consumers nowadays increasingly prefer to purchase commercial jams from markets due to its convenience. Although fresh berries have been extensively studied for their phenolic compounds, a limited number of studies investigating commercially manufactured jams have been conducted so far. Considering this, the objective of this study was to assess the total phenolic, flavonoid, and anthocyanin content and the antioxidant activity of five commonly consumed commercial berry jams (blueberry (Vaccinium myrtillus), blackberry (Rubus fruticosus) and blackcurrant (Ribes nigrun) mixture, blackcurrant (Ribes nigrun), cranberry (Vaccinium macrocarpon) and raspberry (Rubus idaeus)) collected from the market. Even though a possible loss of phenolics, anthocyanins, and a decrease of radical scavenging activity may occur during jam processing and subsequent storage, our data indicated that the selected commercial jams remained good sources of nutritive molecules with antioxidant properties based on the high levels of total phenolics, flavonoids, anthocyanins, and elevated antioxidant activities determined in this study. Additionally, the samples were characterized by GC-MS for their volatile profiles, and terpenes were found to be the dominating class covering more than 74% of volatile compounds in the jams. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Graphical abstract

Open AccessArticle
The Profile and Content of Polyphenols and Carotenoids in Local and Commercial Sweet Cherry Fruits (Prunus avium L.) and Their Antioxidant Activity In Vitro
Antioxidants 2019, 8(11), 534; https://doi.org/10.3390/antiox8110534 - 08 Nov 2019
Abstract
The aim of this study was to evaluate and compare the content of a number of bioactive compounds and antioxidant activity of fruits of selected local and commercial sweet cherry (Prunus avium L.) cultivars. The experiment showed that the selected cultivars of [...] Read more.
The aim of this study was to evaluate and compare the content of a number of bioactive compounds and antioxidant activity of fruits of selected local and commercial sweet cherry (Prunus avium L.) cultivars. The experiment showed that the selected cultivars of sweet cherries differ significantly in the content of polyphenolic compounds and carotenoids. The fruits of commercial sweet cherry cultivars were, on average, richer in polyphenols (the sum of phenolic compounds determined chromatographically), flavonoids, as well as anthocyanins and were characterized by higher antioxidant activity when compared to the local, traditional cultivars. In the group of the traditional sweet cherry cultivars, particular attention could be paid to Black Late cv., showing the highest antioxidant activity of fruits. In the group of commercial sweet cherry cultivars, Cordia and Sylvia fruits could be recognized as being rich in bioactive compounds with high antioxidant activity. Yellow skin cultivars were characterized by the highest concentrations of carotenoids. Strong positive correlations between the identified bioactive compounds and antioxidant activity of fruits were also found. Although different cultivars of sweet cherries show a high variability in phenolics and carotenoids profiles as well as in the antioxidant activity of fruits, they all should be, similarly to other types of cherries, recognized as a rich source of bioactive compounds with an antioxidant potential. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Open AccessArticle
Differentiation of Phenolic Composition Among Tunisian Thymus algeriensis Boiss. et Reut. (Lamiaceae) Populations: Correlation to Bioactive Activities
Antioxidants 2019, 8(11), 515; https://doi.org/10.3390/antiox8110515 - 28 Oct 2019
Abstract
Twelve Tunisian Thymus algeriensis populations growing wild in different bioclimatic zones, extending from the subhumid to the upper-arid bioclimates, were compared regarding their phenolic composition and their ability to serve as antioxidant, anti-acetylcholinesterase, and antibacterial agents. A significant variation of phenol profile was [...] Read more.
Twelve Tunisian Thymus algeriensis populations growing wild in different bioclimatic zones, extending from the subhumid to the upper-arid bioclimates, were compared regarding their phenolic composition and their ability to serve as antioxidant, anti-acetylcholinesterase, and antibacterial agents. A significant variation of phenol profile was observed between the analyzed populations, as assessed by ultra-high-performance liquid chromatography coupled with a diode array detector and an electrospray mass spectrometer (UHPLC-DAD-ESI/MSn) technique. Rosmarinic acid was the main phenolic compound in most populations (383.8–1157.8 µg/mL extract), but still, those from the upper-arid bioclimatic zone were distinguished by the presence of carvacrol (1374.7 and 2221.6 µg/mL extract), which was absent in the remaining ones. T. algeriensis methanolic extracts were found to possess a substantial antioxidant and anti-acetylcholinesterase activities, with significant variation observed between populations, which were correlated to their phenolic contents. The antibacterial activity of the extracts tested against seven bacteria was revealed only by populations collected from upper-arid bioclimate and mainly associated with the presence of carvacrol. Extracts revealed a bacteriostatic effect against all bacteria (MIC = 1.4 mg/mL). Yet, the bactericidal activity (MBC = 1.4mg/mL) was restricted to the gram-negative bacteria Escherchia coli. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Graphical abstract

Open AccessArticle
Impact of Cold versus Hot Brewing on the Phenolic Profile and Antioxidant Capacity of Rooibos (Aspalathus linearis) Herbal Tea
Antioxidants 2019, 8(10), 499; https://doi.org/10.3390/antiox8100499 - 21 Oct 2019
Abstract
Consumption of rooibos (Aspalathus linearis) as herbal tea is growing in popularity worldwide and its health-promoting attributes are mainly ascribed to its phenolic composition, which may be affected by the brewing conditions used. An aspect so far overlooked is the impact [...] Read more.
Consumption of rooibos (Aspalathus linearis) as herbal tea is growing in popularity worldwide and its health-promoting attributes are mainly ascribed to its phenolic composition, which may be affected by the brewing conditions used. An aspect so far overlooked is the impact of cold brewing vs regular brewing and microwave boiling on the (poly) phenolic profile and in vitro antioxidant capacity of infusions prepared from red (‘fermented’, oxidized) and green (‘unfermented’, unoxidized) rooibos, the purpose of the present study. By using an untargeted metabolomics-based approach (UHPLC-QTOF mass spectrometry), 187 phenolic compounds were putatively annotated in both rooibos types, with flavonoids, tyrosols, and phenolic acids the most represented type of phenolic classes. Multivariate statistics (OPLS-DA) highlighted the phenolic classes most affected by the brewing conditions. Similar antioxidant capacities (ORAC and ABTS assays) were observed between cold- and regular-brewed green rooibos and boiled-brewed red rooibos. However, boiling green and red rooibos delivered infusions with the highest antioxidant capacities and total polyphenol content. The polyphenol content strongly correlated with the in vitro antioxidant capacities, especially for flavonoids and phenolic acids. These results contribute to a better understanding of the impact of the preparation method on the potential health benefits of rooibos tea. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
Isolation of Phytochemicals from Bauhinia variegata L. Bark and Their In Vitro Antioxidant and Cytotoxic Potential
Antioxidants 2019, 8(10), 492; https://doi.org/10.3390/antiox8100492 - 17 Oct 2019
Abstract
Plants have been the basis of traditional medicine since the dawn of civilizations. Different plant parts possess various phytochemicals, playing important roles in preventing and curing diseases. Scientists, through extensive experimental studies, are playing an important part in establishing the use of phytochemicals [...] Read more.
Plants have been the basis of traditional medicine since the dawn of civilizations. Different plant parts possess various phytochemicals, playing important roles in preventing and curing diseases. Scientists, through extensive experimental studies, are playing an important part in establishing the use of phytochemicals in medicine. However, there are still a large number of medicinal plants which need to be studied for their phytochemical profile. In this study, the objective was to isolate phytochemicals from bark of Bauhinia variegata L. and to study them for their antioxidant and cytotoxic activities. The bark was extracted with methanol, followed by column chromatography and thus isolating kaempferol, stigmasterol, protocatechuic acid-methyl ester (PCA-ME) and protocatechuic acid (PCA). 2,2-azinobis-3-ethyl-benzothiazoline-6-sulfonic acid (ABTS) and 2, 2’-diphenyl-1-picrylhydrazyl radical (DPPH) radical scavenging assays were utilized for assessment of antioxidant activity, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) dye reduction assay was used to determine cytotoxic activity against C-6 glioma rat brain, MCF-7 breast cancer, and HCT-15 colon cancer cell lines. The compounds were found to have significant antioxidant and cytotoxic activity. Since there is a considerable increase in characterizing novel chemical compounds from plant parts, the present study might be helpful for chemotaxonomic determinations, for understanding of medicinal properties as well as for the quality assessment of herbal supplements containing B. variegata bark, thus establishing its use in traditional medicine. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
Untargeted Metabolomic Profiling, Multivariate Analysis and Biological Evaluation of the True Mangrove (Rhizophora mucronata Lam.)
Antioxidants 2019, 8(10), 489; https://doi.org/10.3390/antiox8100489 - 16 Oct 2019
Abstract
Currently, there is a renewed interest towards the development of plant-based pharmacophores. In this work, 16 extracts prepared from the leaves, twigs, roots and fruits of a hydro-halophyte, Rhizophora mucronata Lam. (Family: Rhizophoraceae), were studied for possible antioxidant activity and the phenolic profiles [...] Read more.
Currently, there is a renewed interest towards the development of plant-based pharmacophores. In this work, 16 extracts prepared from the leaves, twigs, roots and fruits of a hydro-halophyte, Rhizophora mucronata Lam. (Family: Rhizophoraceae), were studied for possible antioxidant activity and the phenolic profiles established. Thereafter, enzymatic inhibitory activities (α-amylase, α-glucosidase, tyrosinase, acetyl- (AChE), butyrylcholinesterase (BChE), lipase, and elastase) were assessed. The total phenolic, flavonoid, phenolic acid, tannin, flavanol and triterpenoid content were estimated using standard assays. An untargeted metabolomics-based approach, based on ultra-high-pressure liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (UHPLC-QTOF-MS) followed by multivariate statistics, was then used to comprehensively profile and describe the phenolics present. UHPLC-QTOF-MS allowed for putatively annotating 104 phenolic acids, 103 flavonols, 94 flavones, 71 anthocyanins, 66 tyrosols, 29 lignans, 15 alkylphenols and 10 stilbenes in the extracts. Nine strains (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Methicillin-resistant Staphylococcus aureus (MRSA), Salmonella enteritidis, Sarcina lutea, Proteus mirabilis, Bacillus cereus and Candida albicans) were then used to investigate the antimicrobial properties. The methanolic twig extract exhibited significant reducing potential towards Cu (II)/Cu (I) and Fe (III)/Fe (II) (1336.88 ± 15.70 and 710.18 ± 21.04 mg TE/g, respectively) and was the most potent DPPH radical scavenger (807.07 ± 6.83 mg TE/g). Additionally, the methanolic twig extract showed significant inhibition against most targeted enzymes. Anti-microbial results showed that all extracts were active against MRSA. Multivariate analysis demonstrated that the phenolic profile of ethyl acetate extracts and leaves were the two most discriminative parameters in terms of solvents and organs, respectively. The present findings indicated that R. mucronata may be further explored for the management/prevention of oxidative stress, neurodegenerative complications and hyperpigmentation. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
LC-ESI-QTOF/MS Characterization of Phenolic Compounds in Palm Fruits (Jelly and Fishtail Palm) and Their Potential Antioxidant Activities
Antioxidants 2019, 8(10), 483; https://doi.org/10.3390/antiox8100483 - 14 Oct 2019
Abstract
Palm fruits have gained growing attention for their nutrition values and health promotion perspectives. They have a diverse range of bioactive compounds including carotenoids, vitamins, dietary fibres and especially polyphenolic compounds. These polyphenolic compounds contribute to the putative health benefits of palm fruits. [...] Read more.
Palm fruits have gained growing attention for their nutrition values and health promotion perspectives. They have a diverse range of bioactive compounds including carotenoids, vitamins, dietary fibres and especially polyphenolic compounds. These polyphenolic compounds contribute to the putative health benefits of palm fruits. Nevertheless, the detailed information about these polyphenols in palm fruits is limited. The present work was conducted to comprehensively characterize polyphenols in two palm fruits, jelly palm (Butia ordorata) and fishtail palm (Caryota uren), using liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF/MS) and assess their antioxidant potential. The total phenolic content (TPC), total tannins content (TTC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant assay and 2,2′-azinobis-(3-ethylbenzo-thiazoline-6-sulfonic acid) (ABTS) scavenging abilities and ferric reducing antioxidant power (FRAP) were higher in the jelly palm fruit while total flavonoid contents (TFC) were higher in the fishtail palm. The LC-ESI-QTOF/MS tentatively identified a total of 86 phenolic compounds in both jelly and fishtail palm fruits. Although both palm fruits exhibited different phenolic profiles, hydroxycinnamic acids and flavonols were the most common in both. In high performance liquid chromatography photodiode array (HPLC-PDA) quantification, 4-hydroxybenzoic acid (317.46 ± 4.68 µg/g) and catechin (4724.00 ± 32.39 µg/g) were the most abundant phenolic acid and flavonoid quantified in the jelly palm fruit, respectively. Quercetin (557.28 ± 7.81 µg/g) and kaempferol 3-O-glucoside (220.99 ± 2.06 µg/g) were the most abundant flavonoids quantified in the fishtail palm. Our study indicates that palm fruit is a good source of polyphenols and has strong antioxidant potential for health promotion. Furthermore, this study provides the scientific basis for an exploitation of jelly and fishtail palm fruits in the food, pharmaceutical and nutraceutical industries. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Graphical abstract

Open AccessArticle
Phytochemical Constituents and Antioxidant Activity of Oudneya Africana L. Leaves Extracts: Evaluation Effects on Fatty Acids and Proteins Oxidation of Beef Burger during Refrigerated Storage
Antioxidants 2019, 8(10), 442; https://doi.org/10.3390/antiox8100442 - 01 Oct 2019
Cited by 1
Abstract
Five Oudneya Africana (OA) leaves extracts were screened for their total phenolic (TPC), total flavonoid (TFC), condensed tannins (CTC) content, as well as their antioxidant capacity. The highest amount of TPC (661.66 ± 0.08 mg GAE/g), TFC (344.68 ± 0.44 mg QE/g) and [...] Read more.
Five Oudneya Africana (OA) leaves extracts were screened for their total phenolic (TPC), total flavonoid (TFC), condensed tannins (CTC) content, as well as their antioxidant capacity. The highest amount of TPC (661.66 ± 0.08 mg GAE/g), TFC (344.68 ± 0.44 mg QE/g) and TCT (90.18 ± 0.49 mg CE/g) was recorded to ethanol, acetone, and dichloromethane extracts, respectively. For 2,2-diphenyl-1-picrylhydrazyl (DPPH) (22.00 ± 0.03 µg/mL) and Reducing Power Assay (FRAP) (269.00 ± 0.01µg/mL) assays, ethanol extract showed the potent activity, while with ABTS test, acetone extract was the most active (761.15 ± 0.09 µg/mL). HPLC-MS analysis of acetonic and ethanolic extracts reveals the predominance of quinic acid, chlorogenic acid, 4-O-caffeoylquinic acid, and rutin compounds. The addition effect evaluation of OA extracts in beef burger preservation demonstrates the powerful effect (p < 0.05) of acetonic and ethanolic ones (0.03%) to inhibit lipids oxidation during storage for 10 days, given by the lowest increase in Thiobarbituric Acid-reactive Substances (TBARS) values as compared to the (−) control with a significant difference between free thiols values. In addition, these two extracts appear to be effective (p < 0.05) for pH stability, color, and sensory parameters as compared to (+) and (−) controls and aqueous extract. Hamburger odour was considered as a dependent variable in multiple linear regression analysis, where the models results showed that physicochemical parameters determine more burger odour than sensorial ones. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Open AccessArticle
Phenolic Compounds and Antioxidant Activities of Potato Cultivars with White, Yellow, Red and Purple Flesh
Antioxidants 2019, 8(10), 419; https://doi.org/10.3390/antiox8100419 - 20 Sep 2019
Abstract
The contents of total phenolics (TPC), individual phenolic acid and antioxidant activities in the free and bound fractions of potato with different flesh colors were systematically investigated. The TPC and antioxidant capacity in the bound fraction was significantly lower than that in the [...] Read more.
The contents of total phenolics (TPC), individual phenolic acid and antioxidant activities in the free and bound fractions of potato with different flesh colors were systematically investigated. The TPC and antioxidant capacity in the bound fraction was significantly lower than that in the free fraction. Chlorogenic acid, neochlorogenic acid, cryptochlorogenic acid, caffeic acid, p-coumaric acid and ferulic acid were detected in the free fraction with chlorogenic acid being the most predominant, accounting for 35.21–81.78% of the total content. Caffeic acid, p-coumaric acid and ferulic acid were detected in the bound fraction in the colored potato with caffeic acid being the major one. In the free fraction, the content of each individual phenolic acid had positive correlation with antioxidant activity. In the bound fraction, caffeic acid and p-coumaric acid showed positive correlation with antioxidant activity. This study promotes further understanding of the correlations among TPC, phenolic acids and antioxidant activity. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessCommunication
Effects of Tannase and Ultrasound Treatment on the Bioactive Compounds and Antioxidant Activity of Green Tea Extract
Antioxidants 2019, 8(9), 362; https://doi.org/10.3390/antiox8090362 - 01 Sep 2019
Cited by 1
Abstract
The present study investigated the effects of tannase and ultrasound treatment on the bioactive compounds and antioxidant activity of green tea extract. The single-factor experiments and the response surface methodology were conducted to study the effects of parameters on antioxidant activity of green [...] Read more.
The present study investigated the effects of tannase and ultrasound treatment on the bioactive compounds and antioxidant activity of green tea extract. The single-factor experiments and the response surface methodology were conducted to study the effects of parameters on antioxidant activity of green tea extract. The highest antioxidant activity was found under the optimal condition with the buffer solution pH value of 4.62, ultrasonic temperature of 44.12 °C, ultrasonic time of 12.17 min, tannase concentration of 1 mg/mL, and ultrasonic power of 360 W. Furthermore, phenolic profiles of the extracts were identified and quantified by high-performance liquid chromatography. Overall, it was found that tannase led to an increase in gallic acid and a decrease in epigallocatechin gallate, and ultrasounds could also enhance the efficiency of enzymatic reaction. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
Comparison of Chemical Compositions, Antioxidant, and Anti-Photoaging Activities of Paeonia suffruticosa Flowers at Different Flowering Stages
Antioxidants 2019, 8(9), 345; https://doi.org/10.3390/antiox8090345 - 01 Sep 2019
Abstract
Paeonia suffruticosa is an ornamental, edible, and medicinal plant. The ethanolic extracts of P. suffruticosa bud and flower were examined for their antioxidant, anti-photoaging, and phytochemical properties prior to chemometric analysis. The results showed that the bud ethanolic extract (BEE) and the [...] Read more.
Paeonia suffruticosa is an ornamental, edible, and medicinal plant. The ethanolic extracts of P. suffruticosa bud and flower were examined for their antioxidant, anti-photoaging, and phytochemical properties prior to chemometric analysis. The results showed that the bud ethanolic extract (BEE) and the flower (the early flowering stage) ethanolic extract (FEE) had better antioxidant activities, and significantly increased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and reduced the levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the skin tissues. In total, 68 compounds, including 20 flavonoids, 15 phenolic derivatives, 12 terpenoids, 9 fatty acids, and 12 others were identified or tentatively identified by ultra-fast liquid chromatography quadrupole time-of-flight mass spectrometry (UFLC-Q-TOF-MS). Gallic acid, 1,2,3,4,6-O-pentagalloyl glucose, paeoniflorin, and oxypaeoniflorin were predominant compounds in the extracts. Taken together, P. suffruticosa flowers are a candidate for functional material in food and health related industries, and their optimal time to harvest is before the early flowering stage. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Graphical abstract

Open AccessArticle
Polyphenolic Composition and Antioxidant Activity of Uncaria tomentosa Commercial Bark Products
Antioxidants 2019, 8(9), 339; https://doi.org/10.3390/antiox8090339 - 23 Aug 2019
Abstract
Uncaria tomentosa, which is widely commercialized as an herbal medicine, constitutes an important source of secondary metabolites with diverse biological activities. For instance, we have previously reported, for the first time, of a polyphenolic profile rich in proanthocyanidins from extracts of U. [...] Read more.
Uncaria tomentosa, which is widely commercialized as an herbal medicine, constitutes an important source of secondary metabolites with diverse biological activities. For instance, we have previously reported, for the first time, of a polyphenolic profile rich in proanthocyanidins from extracts of U. tomentosa plants, as well as their antioxidant capacity, antimicrobial activity on aerial bacteria, and cytotoxicity on cancer cell lines. These promising results prompted this research to evaluate the polyphenolic contents of U. tomentosa commercial products. We report a detailed study on the polyphenolic composition of extracts from U. tomentosa bark products (n = 18) commercialized in Costa Rica and Spain. Using HPLC-DAD/TQ-ESI-MS, a total of 25 polyphenolic compounds were identified, including hydroxybenzoic and hydroxycinnamic acids, flavan-3-ol monomers, procyanidin dimers, procyanidin trimers, as well as propelargonidin dimers. Our findings on the polyphenolic profile for all commercial samples show analogous composition to previous reports on U. tomentosa bark material, for instance a 41–49% content of procyanidin dimers and the presence of propelargonidin dimers (8–15%). However, most of the 18 commercial samples exhibit low proanthocyanidin contents (254.8–602.8 µg/g), more similar to previous U. tomentosa inner bark reports, while some exhibit better results, with one sample (SP-2) showing the highest contents (2386.5 µg/g) representing twice the average value of all 18 commercial products. This sample also exhibits the highest total phenolics (TP) and total proanthocyanidins (PRO) contents, as well as the highest Oxygen Radical Absorbance Capacity (ORAC) value (1.31 µg TE/g). One-way Analysis of Variance (ANOVA) with a Tukey post hoc test indicated significant difference (p < 0.05) between products from Costa Rica and Spain for TP and PRO findings, with samples from Spain exhibiting a higher average value. In addition, Pearson correlation analysis results showed a positive correlation (p < 0.05) between TP, PRO, and ORAC results, and an especially important correlation between ORAC antioxidant values and procyanidin dimers (r = 0.843, p < 0.05), procyanidin trimers (r = 0.847, p < 0.05), and propelargonidin dimers (r = 0.851, p < 0.05) contents. Finally, Principal Component Analysis (PCA) results indicated some variability in the composition regardless of their origin. However, only one sample (SP-2) stands out significatively, showing the highest PC1 because of its particularly high proanthocyanidins contents, which could be attributed to the 15% bark polyphenolic extract labeled in this commercial product, which differentiate this sample from all other 17 commercial samples. Therefore, our findings confirmed previous results on the value of extracts in the elaboration of potential commercial products from U. tomentosa, rich in proanthocyanidins and exhibiting high antioxidant activity. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
Caffeoylquinic Acids and Flavonoids of Fringed Sagewort (Artemisia frigida Willd.): HPLC-DAD-ESI-QQQ-MS Profile, HPLC-DAD Quantification, in Vitro Digestion Stability, and Antioxidant Capacity
Antioxidants 2019, 8(8), 307; https://doi.org/10.3390/antiox8080307 - 14 Aug 2019
Cited by 1
Abstract
Fringed sagewort (Artemisia frigida Willd., Compositae family) is a well-known medicinal plant in Asian medical systems. Fifty-nine hydroxycinnamates and flavonoids have been found in A. frigida herbs of Siberian origin by high-performance liquid chromatography with diode array and electrospray triple quadrupole mass [...] Read more.
Fringed sagewort (Artemisia frigida Willd., Compositae family) is a well-known medicinal plant in Asian medical systems. Fifty-nine hydroxycinnamates and flavonoids have been found in A. frigida herbs of Siberian origin by high-performance liquid chromatography with diode array and electrospray triple quadrupole mass detection (HPLC-DAD-ESI-QQQ-MS). Their structures were determined after mass fragmentation analysis as caffeoylquinic acids, flavone O-/C-glycosides, flavones, and flavonol aglycones. Most of the discovered components were described in A. frigida for the first time. It was shown that flavonoids with different types of substitution have chemotaxonomic significance for species of Artemisia subsection Frigidae (section Absinthium). After HPLC-DAD quantification of 16 major phenolics in 21 Siberian populations of A. frigida and subsequent principal component analysis, we found substantial variation in the selected compounds, suggesting the existence of two geographical groups of A. frigida. The antioxidant activity of A. frigida herbal tea was determined using 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH) and hydrophilic/lipophilic oxygen radical absorbance capacity (ORAC) assays and DPPH-HPLC profiling, revealing it to be high. The effect of digestive media on the phenolic profile and antioxidant capacity of A. frigida herbal tea was assessed under simulated gastrointestinal digestion. We found a minor reduction in caffeoylquinic acid content and ORAC values, but remaining levels were satisfactory for antioxidant protection. These results suggest that A. frigida and its food derivate herbal tea could be recommended as new plant antioxidants rich in phenolics. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
A Green Ultrasound-Assisted Extraction Optimization of the Natural Antioxidant and Anti-Aging Flavonolignans from Milk Thistle Silybum marianum (L.) Gaertn. Fruits for Cosmetic Applications
Antioxidants 2019, 8(8), 304; https://doi.org/10.3390/antiox8080304 - 14 Aug 2019
Abstract
Silybum marianum (L.) Gaertn. (aka milk thistle) constitutes the source of silymarin (SILM), a mixture of different flavonolignans and represents a unique model for their extraction. Here we report on the development and validation of an ultrasound-assisted extraction (UAE) method of S. marianum [...] Read more.
Silybum marianum (L.) Gaertn. (aka milk thistle) constitutes the source of silymarin (SILM), a mixture of different flavonolignans and represents a unique model for their extraction. Here we report on the development and validation of an ultrasound-assisted extraction (UAE) method of S. marianum flavonolignans follow by their quantification using LC system. The optimal conditions of this UAE method were: aqueous EtOH 54.5% (v/v) as extraction solvent, with application of an ultrasound (US) frequency of 36.6 kHz during 60 min at 45 °C with a liquid to solid ratio of 25:1 mL/g dry weight (DW). Following its optimization using a full factorial design, the extraction method was validated according to international standards of the association of analytical communities (AOAC) to ensure precision and accuracy in the quantitation of each component of the SILM mixture. The efficiency of this UAE was compared with maceration protocol. Here, the optimized and validated conditions of the UAE allowed the highest extraction yields of SILM and its constituents in comparison to maceration. During UAE, the antioxidant capacity of the extracts was retained, as confirmed by the in vitro assays CUPRAC (cupric ion reducing antioxidant capacity) and inhibition of AGEs (advanced glycation end products). The skin anti-aging potential of the extract obtained by UAE was also confirmed by the strong in vitro cell-free inhibition capacity of both collagenase and elastase. To summarize, the UAE procedure presented here is a green and efficient method for the extraction and quantification of SILM and its constituents from the fruits of S. marianum, making it possible to generate extracts with attractive antioxidant and anti-aging activities for future cosmetic applications. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
Antioxidant and Anti-Inflammatory Activities of the Crude Extracts of Moringa oleifera from Kenya and Their Correlations with Flavonoids
Antioxidants 2019, 8(8), 296; https://doi.org/10.3390/antiox8080296 - 09 Aug 2019
Cited by 1
Abstract
Moringa oleifera Lam. (M. oleifera) is commonly distributed and utilized in tropical and sub-tropical areas. There has been a large number of reports on the antioxidant and anti-inflammatory activity of its leaves, but only a few about its seeds and roots. [...] Read more.
Moringa oleifera Lam. (M. oleifera) is commonly distributed and utilized in tropical and sub-tropical areas. There has been a large number of reports on the antioxidant and anti-inflammatory activity of its leaves, but only a few about its seeds and roots. Hence, in this work we aimed to systematically compare the antioxidant and anti-inflammatory activities of the ethanol crude extracts of leaves, seeds, and roots of M. oleifera from Kenya, and further correlate the differential activities with the chemical constituents from these three parts. The antioxidant activities were measured by using three different assays (DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2′-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) and FRAP (Ferric-Reducing Antioxidant Power), respectively). Results showed that the leaf extracts displayed the highest DPPH radical scavenging and FRAP total reducing power activities with IC50 values of 1.02 ± 0.13 mg/mL and 0.99 ± 0.06 mM Fe2+/g, respectively; the leaf and root extracts exhibited potential ABTS radical scavenging activities with the IC50 values of 1.36 ± 0.02 and 1.24 ± 0.03 mg/mL. Meanwhile, the leaf and seed extracts (11.1–100 µg/mL) also exerted obvious anti-inflammatory activities, as indicated by the inhibition of NO production. To further reveal correlations between these differential activities with the chemical constituents in the three organs, the total flavonoids content (TFC) of the three different extracts were evaluated, and the TFC of leaves, seeds and roots were found to be 192.36 ± 2.96, 5.89 ± 0.65 and 106.79 ± 2.12 mg rutin equivalent (RE)/g, respectively. These findings indicated the important impacts of the total flavonoid contents on antioxidant and anti-inflammatory activities. Additionally, we further determined the phytochemical profiles of M. oleifera by HPLC-UV/ESI-MS/MS, and identified most of the chemical constituents of leaves as flavonoids. In summary, the leaves of M. oleifera are a better potential natural source of antioxidants and anti-inflammatory agents, and very promising for development into the health promoting dietary supplements. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
Hepatoprotection of Mentha aquatica L., Lavandula dentata L. and Leonurus cardiaca L.
Antioxidants 2019, 8(8), 267; https://doi.org/10.3390/antiox8080267 - 02 Aug 2019
Abstract
The phenolic composition of hydroethanolic extracts of Mentha aquatica L., Lavandula dentata L. and Leonurus cardiaca L., obtained from plants grown under organic cultivation, was determined and their hepatoprotective effects were investigated in vitro. L. cardiaca extract was rich in phenylethenoid glycosides, especially [...] Read more.
The phenolic composition of hydroethanolic extracts of Mentha aquatica L., Lavandula dentata L. and Leonurus cardiaca L., obtained from plants grown under organic cultivation, was determined and their hepatoprotective effects were investigated in vitro. L. cardiaca extract was rich in phenylethenoid glycosides, especially lavandolifolioside (254 ± 36 μg/mg), whereas rosmarinic acid and eriodictyol-O-rutinoside were the major phenolic compounds of L. dentata and M. aquatica extracts, accounting for 68 ± 7 μg/mg and 145 ± 22 μg/mg, respectively. These differential phenolic components presumably account for their dissimilar antioxidant properties. While L. cardiaca extract showed moderate biological effects, M. aquatica extract displayed high antioxidant activity in chemical models, and that of L. dentata was effective in counteracting potassium dichromate-induced ROS generation in human hepatocarcinoma cells. Moreover, M. aquatica extract (50 μg/mL) and its mixture (50%/50%) with L. dentata extract displayed an effective cytoprotective effect. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
Comparative Examination of Antioxidant Capacity and Fingerprinting of Unfractionated Extracts from Different Plant Parts of Quinoa (Chenopodium quinoa) Grown under Greenhouse Conditions
Antioxidants 2019, 8(8), 238; https://doi.org/10.3390/antiox8080238 - 24 Jul 2019
Abstract
Integrated surveys of metabolic profiles and antioxidant capacity from Chenopodium quinoa have been limited and have particularly focused on an examination of seeds and leaves. According to this, the main aim of the present study was to address an evaluation of the antioxidant [...] Read more.
Integrated surveys of metabolic profiles and antioxidant capacity from Chenopodium quinoa have been limited and have particularly focused on an examination of seeds and leaves. According to this, the main aim of the present study was to address an evaluation of the antioxidant activity of crude ethanolic extracts from different plant parts (leaves, stems, roots, flowers, and seeds) harvested at different times during growth and processed by two distinct drying methods: Air-drying and freeze-drying. In order to characterize the resulting extracts, the total content of phenolics (TPC) and flavonoids (TFC) was then measured through the Folin–Ciocalteu method, while antioxidant capacity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and ferric-reducing antioxidant power (FRAP) methods. Parallel to this evaluation, extracts were profiled by LC-DAD-ESI-MS. Data analysis was supported by statistics. Most of the extracts obtained from freeze-dried samples showed higher TPC values ranging from 6.02 to 43.47 milligram of gallic acid equivalents per gram of plant material and a TFC between 1.30 and 12.26 milligram of quercetin equivalents per gram of plant material. After statistical analysis, a low correlation between TPC and TFC values was observed regarding antioxidant capacity from DPPH and FRAP measurements of both drying methods. A multivariate analysis showed that antioxidant components and antioxidant capacity in C. quinoa changed during growth and between plant parts and drying methods. These changes need to be taken into consideration when comparing the production/accumulation of beneficial bioactive compounds in this pseudocereal. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Graphical abstract

Open AccessArticle
Phenolic Profiles and Antioxidant Activities of 30 Tea Infusions from Green, Black, Oolong, White, Yellow and Dark Teas
Antioxidants 2019, 8(7), 215; https://doi.org/10.3390/antiox8070215 - 10 Jul 2019
Cited by 3
Abstract
Tea is among the most consumed drink worldwide, and its strong antioxidant activity is considered as the main contributor to several health benefits, such as cardiovascular protection and anticancer effect. In this study, the antioxidant activities of 30 tea infusions, which were obtained [...] Read more.
Tea is among the most consumed drink worldwide, and its strong antioxidant activity is considered as the main contributor to several health benefits, such as cardiovascular protection and anticancer effect. In this study, the antioxidant activities of 30 tea infusions, which were obtained by the mimic of drinking tea of the public, from green, black, oolong, white, yellow and dark teas, were evaluated using ferric-reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) assays, ranging from 504.80 ± 17.44 to 4647.47 ± 57.87 µmol Fe2+/g dry weight (DW) and 166.29 ± 24.48 to 2532.41 ± 50.18 µmol Trolox/g DW, respectively. Moreover, their total phenolic contents (TPC) were detected by Folin-Ciocalteu assay and were in the range of 24.77 ± 2.02 to 252.65 ± 4.74 mg gallic acid equivalent (GAE)/g DW. Generally, Dianqing Tea, Lushan Yunwu Tea, and Xihu Longjing Tea showed the strongest antioxidant activities among 30 teas. Furthermore, the phenolic compounds in tea infusions were identified and quantified, with catechins most commonly detected, especially in green tea infusions, which were main contributors to their antioxidant activities. Besides tea polyphenols, considerable content of caffeine also presented in 30 tea infusions. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
Polyphenolic Profile and Antioxidant Capacity of Extracts from Gordonia axillaris Fruits
Antioxidants 2019, 8(6), 150; https://doi.org/10.3390/antiox8060150 - 29 May 2019
Cited by 4
Abstract
An ultrasonic-assisted extraction (UAE) method was adopted to extract natural antioxidants from edible Gordonia axillaris fruit. Single-factor experiments and response surface methodology were conducted to investigate the influences of five different parameters on antioxidant capacity. The optimal conditions of the UAE were 39.78% [...] Read more.
An ultrasonic-assisted extraction (UAE) method was adopted to extract natural antioxidants from edible Gordonia axillaris fruit. Single-factor experiments and response surface methodology were conducted to investigate the influences of five different parameters on antioxidant capacity. The optimal conditions of the UAE were 39.78% ethanol, 30.94 mL/g solvent/material ratio, 59.47 min extraction time, 40 °C temperature, and 400 W ultrasonication power. The antioxidant capacity was 525.05 ± 14.34 µmol Trolox/g DW under the optimal conditions, which was in agreement with the predicted one (531.71 µmol Trolox/g DW). Additionally, in comparison with two traditional methods (maceration and Soxhlet extraction), the established UAE method greatly improved the yield of antioxidants and significantly reduced the extraction time. Besides, nine phenolic compounds were identified and quantified in the extract of Gordonia axillaris fruits by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), including rutin, gallic acid, protocatechuic acid, epicatechin, 2-hydrocinnamic acid, p-coumaric acid, quercetin, epicatechin gallate, and ferulic acid. The richness of phenolic compounds in the Gordonia axillaris fruits indicated its potential health benefits, and its extract rich in antioxidants could be developed into functional food or nutraceuticals with the potential to prevent certain diseases induced by oxidative stress, such as cardiovascular diseases and cancers. This study also provided a way to enhance the economic values of Gordonia axillaris fruits compared to raw fruits. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
The Influence of Vinification Methods and Cultivars on the Volatile and Phenolic Profiles of Fermented Alcoholic Beverages from Cranberry
Antioxidants 2019, 8(5), 144; https://doi.org/10.3390/antiox8050144 - 23 May 2019
Cited by 1
Abstract
This study investigated the effects of vinification techniques and cultivars (Stevens, Pilgrim and Bergman) on cranberry wine quality. Three winemaking technologies were conducted to prepare cranberry musts before fermentation, including traditional red and white vinifications (Red and White), and thermovinification (Thermo). In wine [...] Read more.
This study investigated the effects of vinification techniques and cultivars (Stevens, Pilgrim and Bergman) on cranberry wine quality. Three winemaking technologies were conducted to prepare cranberry musts before fermentation, including traditional red and white vinifications (Red and White), and thermovinification (Thermo). In wine products, proanthocyanins (PACs) and anthocyanins (ANCs) are dominant in phenolics, while esters and alcohols are prevalent in volatiles, with phenylethyl alcohol, β-damascenone, benzyl alcohol, etc. as the main contributors to the aroma. The phenolic compositions of wines were in the same pattern with cultivars: the Stevens and Bergman wines contained the highest amount of ANCs and PACs, respectively, while the Pilgrim wines had the lowest total phenolic contents (TPC), and antioxidant capacities (AOC). Nevertheless, products from Pilgrim cultivar had a distinctive pattern of volatiles compared to Stevens and Bergman, especially for aromatic compounds. Considering vinification methods, Thermo demonstrated advantages on correlations with both phenolic and volatile (polymeric and monomeric) compositions. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Graphical abstract

Open AccessArticle
Extraction Optimization, Antioxidant Capacity and Phenolic Profiling of Extracts from Flesh, Peel and Whole Fruit of New Zealand Grown Feijoa Cultivars
Antioxidants 2019, 8(5), 141; https://doi.org/10.3390/antiox8050141 - 21 May 2019
Cited by 3
Abstract
Feijoa fruit is becoming increasingly popular, yet limited studies have focused on the antioxidant capacity and phenolic profiling of its extracts. In this research, optimization of phenolic extraction from feijoa flesh, peel, and whole fruit from four New Zealand grown cultivars was conducted [...] Read more.
Feijoa fruit is becoming increasingly popular, yet limited studies have focused on the antioxidant capacity and phenolic profiling of its extracts. In this research, optimization of phenolic extraction from feijoa flesh, peel, and whole fruit from four New Zealand grown cultivars was conducted using orthogonal design. Antioxidant activities of the extracts were assessed, followed by phenolic profiling by a validated liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method. For feijoa flesh and whole fruit, the extraction was optimized using 70% ethanol, material to solvent ratio of 1:30, at extraction temperature of 50 °C for 30 min. For feijoa peel, extraction at 50 °C for 60 min using 50% ethanol with a material to solvent ratio of 1:30 were the optimized conditions. Results showed feijoa peel had higher total phenolic content (TPC) and antioxidant activities than the flesh and whole fruit. Overall, the Unique cultivar had a relatively higher TPC and antioxidant activity than the other cultivars tested. A total of 15 phenolic compounds were identified, and seven of them were reported for the first time in feijoa fruit. This is the first systematic investigation on the extraction method, phenolic content, antioxidant activity and phenolic profile of feijoa emphasis on comparison of sample types and cultivars. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
Investigation of In-Vitro Antioxidant and Electrochemical Activities of Isolated Compounds from Salvia chamelaeagnea P.J.Bergius Extract
Antioxidants 2019, 8(4), 98; https://doi.org/10.3390/antiox8040098 - 12 Apr 2019
Cited by 1
Abstract
We have investigated the in-vitro antioxidant activity and electrochemical redox properties of a number of natural compounds (carnosol, carnosic acid, 7-ethoxyrosmanol, ursolic acid, rosmanol and ladanein) isolated from the methanolic extract of Salvia chamelaeagnea collected from the Cape floristic region, South Africa. The [...] Read more.
We have investigated the in-vitro antioxidant activity and electrochemical redox properties of a number of natural compounds (carnosol, carnosic acid, 7-ethoxyrosmanol, ursolic acid, rosmanol and ladanein) isolated from the methanolic extract of Salvia chamelaeagnea collected from the Cape floristic region, South Africa. The results from trolox equivalent antioxidant capacity (TEAC), ferric-ion reducing antioxidant parameter (FRAP) oxygen radical absorbance capacity (ORAC), as well as the inhibition of Fe2+-induced lipid peroxidation showed strong antioxidant capacities for carnosol and rosmanol. A structural analysis of the compounds suggests that multiple OH substitution, conjugation and lactone ring in carnosol and rosmanol are important determinants of the free radical scavenging activity and electrochemical behavior. Pharmacophore generated demonstrates H-donor/acceptor capabilities of the most active compounds. Rosmanol, when compared to other compounds, exhibits the lowest oxidation potential value with an anodic peak potential (Epa) value of 0.11 V, indicating that rosmanol has the highest antioxidant power, which is in good agreement with ORAC and lipid peroxidation experiments. The lipophilic nature of carnosol, carnosic acid and rosmanol enhanced their absorption and activity against oxidative stress related to the treatment of age-related diseases. These results confirm the first report on the in-vitro antioxidant and electrochemical activities of S. chamelaeagnea constituents and underline the medicinal uses of this plant as natural preservatives for skin ageing or in pharmaceutical applications. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
In Vitro Antioxidant and Antimicrobial Properties of Flower, Leaf, and Stem Extracts of Korean Mint
Antioxidants 2019, 8(3), 75; https://doi.org/10.3390/antiox8030075 - 26 Mar 2019
Cited by 4
Abstract
Traditionally, Agastache rugosa (Korean mint) has been widely used to treat various infectious diseases. The aims of this study were to: (i) determine the phenylpropanoid content of the plant using high-performance liquid chromatography; (ii) undertake total anthocyanin, flavonoid, and phenolic assays; (iii) and [...] Read more.
Traditionally, Agastache rugosa (Korean mint) has been widely used to treat various infectious diseases. The aims of this study were to: (i) determine the phenylpropanoid content of the plant using high-performance liquid chromatography; (ii) undertake total anthocyanin, flavonoid, and phenolic assays; (iii) and evaluate the antioxidant and antibacterial properties of the methanol extracts from the stem, leaves, and flowers of Korean mint. The total anthocyanin, flavonoid, and phenolic content assays showed that the flowers had higher phenolic levels than the stem and leaves. The reducing power, the 2,2-diphenyl-1-picrylhydrazyl superoxide radical scavenging abilities, and the hydrogen peroxide radical scavenging activities were also evaluated so that the antioxidant activities of the extracts from the different plant parts could be evaluated. The flower extracts revealed higher antioxidant properties than the other parts. The antibacterial properties of the methanol extracts from A. rugosa were analyzed by the disc diffusion method, and the flower extracts had higher antibacterial activities against the six bacterial strains used in the study than the other parts. This study provides information on the synergistic antioxidant and antibacterial properties of phenolics derived from the different parts of Korean mint. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Open AccessArticle
Comparison of the Phenolic Profiles of Soaked and Germinated Peanut Cultivars via UPLC-QTOF-MS
Antioxidants 2019, 8(2), 47; https://doi.org/10.3390/antiox8020047 - 20 Feb 2019
Cited by 3
Abstract
Diverse peanut varieties are widely cultivated in China. However, few studies have investigated the effects of germination on the phenolic profiles and antioxidant activities of specific Chinese peanut cultivars. Therefore, this study was conducted to evaluate the effects of germination on total phenolic [...] Read more.
Diverse peanut varieties are widely cultivated in China. However, few studies have investigated the effects of germination on the phenolic profiles and antioxidant activities of specific Chinese peanut cultivars. Therefore, this study was conducted to evaluate the effects of germination on total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity, and phenolic profiles of seven peanut cultivars in China. The TPC, TFC, and antioxidant activities were determined by spectrophotometry, while phenolic profiles were analyzed by using ultra-high performance liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry (UPLC-QTOF-MS). The results found that germination significantly increased TPC, TFC, and antioxidant activity. Antioxidant activity was found to be closely related to TPC in germinated peanut extracts, which indicates that phenolics are the main contributors of antioxidants in germinated peanuts. In addition, germination induced significant changes in polyphenolic profiles. In the analyzed samples, 36 phenolic compounds were identified in which most were flavonoids. Overall, these findings highlight that germinated peanuts can be a good natural source of natural antioxidants for human consumption and functional food development. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Figure 1

Review

Jump to: Research

Open AccessReview
Bee Collected Pollen and Bee Bread: Bioactive Constituents and Health Benefits
Antioxidants 2019, 8(12), 568; https://doi.org/10.3390/antiox8120568 - 20 Nov 2019
Abstract
Bee products were historically used as a therapheutic approach and in food consumption, while more recent data include important details that could validate them as food supplements due to their bioproperties, which support their future use as medicines. In this review data, data [...] Read more.
Bee products were historically used as a therapheutic approach and in food consumption, while more recent data include important details that could validate them as food supplements due to their bioproperties, which support their future use as medicines. In this review data, data collected from bee pollen (BP) and bee bread (BB) essays will be discussed and detailed for their nutritional and health protective properties as functional foods. Dietary antioxidants intake derived from BP and BB have been associated with the prevention and clinical treatment of multiple diseases. The beneficial effects of BP and BB on health result from the presence of multiple polyphenols which possess anti-inflammatory properties, phytosterols and fatty acids, which play anticancerogenic roles, as well as polysaccharides, which stimulate immunological activity. From the main bioactivity studies with BP and BB, in vitro studies and animal experiments, the stimulation of apoptosis and the inhibition of cell proliferation in multiple cell lines could be one of the major therapeutic adjuvant effects to be explored in reducing tumor growth. Tables summarizing the main data available in this field and information about other bio-effects of BP and BB, which support the conclusions, are provided. Additionally, a discussion about the research gaps will be presented to help further experiments that complete the tree main World Health Organization (WHO) Directives of Efficiency, Safety and Quality Control for these products. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Graphical abstract

Open AccessReview
The Odyssey of Bioactive Compounds in Avocado (Persea americana) and Their Health Benefits
Antioxidants 2019, 8(10), 426; https://doi.org/10.3390/antiox8100426 - 24 Sep 2019
Abstract
Persea americana, commonly known as avocado, has recently gained substantial popularity and is often marketed as a “superfood” because of its unique nutritional composition, antioxidant content, and biochemical profile. However, the term “superfood” can be vague and misleading, as it is often [...] Read more.
Persea americana, commonly known as avocado, has recently gained substantial popularity and is often marketed as a “superfood” because of its unique nutritional composition, antioxidant content, and biochemical profile. However, the term “superfood” can be vague and misleading, as it is often associated with unrealistic health claims. This review draws a comprehensive summary and assessment of research performed in the last few decades to understand the nutritional and therapeutic properties of avocado and its bioactive compounds. In particular, studies reporting the major metabolites of avocado, their antioxidant as well as bioavailability and pharmacokinetic properties, are summarized and assessed. Furthermore, the potential of avocado in novel drug discovery for the prevention and treatment of cancer, microbial, inflammatory, diabetes, and cardiovascular diseases is highlighted. This review also proposes several interesting future directions for avocado research. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Graphical abstract

Open AccessReview
The Modern Use of an Ancient Plant: Exploring the Antioxidant and Nutraceutical Potential of the Maltese Mushroom (Cynomorium Coccineum L.)
Antioxidants 2019, 8(8), 289; https://doi.org/10.3390/antiox8080289 - 07 Aug 2019
Cited by 1
Abstract
In the continuous scientific search for new safe and effective drugs, there has recently been a rediscovery of natural substances as a potential reservoir of innovative therapeutic solutions for human health, with the prospect of integrating with and sometimes replacing conventional drugs. Cynomorium [...] Read more.
In the continuous scientific search for new safe and effective drugs, there has recently been a rediscovery of natural substances as a potential reservoir of innovative therapeutic solutions for human health, with the prospect of integrating with and sometimes replacing conventional drugs. Cynomorium coccineum subsp. coccineum is a holoparasitic plant well known in ethnopharmacology, although its current use as a curative remedy is reported only in some ethnic groups of North Africa and the Arabian Peninsula. Often known as ‘Maltese mushroom’ due to its unique appearance and the absence of chlorophyll, C. coccineum is present in almost all of the Mediterranean Basin. It is only recently that a few research groups have begun to look for confirmation of some of its traditional uses to highlight previously unknown biological activities. Here, we review the recent scientific findings on the plant’s phytochemistry and the most significant descriptions of some of its antioxidant and biological activities (antimicrobial, anticancer, pro-erectile, and anti-tyrosinase enzyme) both in vivo and in vitro. Some of these may be promising from the perspective of food and cosmetic formulations. The purpose of this review is to provide an initial impetus to those who, in the foreseeable future, will want to increase the knowledge and possible applications of this plant full of history, charm, and mystery. Full article
(This article belongs to the Special Issue Phenolic Profiling and Antioxidant Capacity in Plants)
Show Figures

Graphical abstract

Back to TopTop