Search Results (34)

The use of antioxidants in the dermatocosmetic industry has become increasingly popular to help protect and stabilize other sensitive active ingredients, prolonging the effectiveness and durability of the cosmetic product. Grape pomace, as the main by-product generated through winemaking, and Polygonum cuspidatum, concentrate bioactive metabolites with high antioxidant activity. Hydroalcoholic extracts obtained from grape pomace (Merlot and Feteasca Neagra varieties) and the root and flower of Japanese knotweed, respectively, alone and in mixtures, were characterized, and preliminary assays were conducted for their incorporation in two gel-based cosmetic formulations. The characterization of the extracts revealed the presence of catechin, vanillic acid, caffeic acid, myricetin, resveratrol, and kaempferol. The hydroalcoholic extract of P. cuspidatum flower and root was found to have the highest content of total phenolic compounds (10.920 ± 0.268 mg GAE/mL, respectively, 4.751 ± 0.072 mg GAE/mL), and the highest antioxidant activity (expressed as DPPH Radical Scavenging Capacity, IC₅₀) by 28.04 ± 1.12 µg GAE/mL and 83.91 ± 1.13 µg GAE/mL, respectively. Catechin was the most abundant polyphenol found in pomace extract (687.87 mg/kg). The type and the concentration of the plant extract used in dermatocosmetic gel formulations influenced their antioxidant activity. Encapsulation of P. cuspidatum flower extract in liposomes prior to their incorporation into the gel formulation demonstrated the role of liposomes in enhancing the stability and modulation of phenolic compound delivery. It is worth noting that this dermatocosmetic formulation, which contains the flower extract of P. cuspidatum, was the subject of a pending patent application. Full article

Horseradish (Armoracia rusticana) is a plant with a long tradition of use and numerous remarkable properties. It is especially appreciated for its antioxidant, antimicrobial, and anti-inflammatory effects. The therapeutic potential of the subject in the management of allergies has received comparatively less attention, despite its composition being rich in bioactive substances. The purpose of this research was to enhance the recovery of bioactive compounds from horseradish by applying an optimized ultrasound-assisted extraction process modelled through Design-Expert software (version 11). Spectrophotometric and chromatographic analyses revealed higher concentrations of polyphenols in extracts obtained with a methanol–water mixture (1:1, v/v) compared to ultrapure water, confirming the efficiency of solvents with lower polarity. The antioxidant activity was found to be significant, with the hydroalcoholic extract achieving 96.93% and the aqueous extract reaching 89.34%. The vitamin C content was determined to be 105.32 mg/100 g and 90.35 mg/100 g, respectively. The polyphenolic profile and fatty acid analysis confirmed the presence of bioactive compounds previously reported as antiallergenic, including protocatechuic, p-hydroxybenzoic, vanillic, caffeic, chlorogenic, p-coumaric, rosmarinic acids, and polyunsaturated fatty acids such as linoleic and linolenic acids, alongside the vitamin C content. The results of the present study confirm that horseradish is a rich natural source of bioactive compounds, particularly antioxidants, which may be of interest for further studies related to functional applications. Full article

The aim of this study was to investigate the suitability of Pressurized Liquid Extraction (PLE) and Supercritical Fluid Extraction (SFE) for Quercus robur bark and Artemisia vulgaris extraction. PLE of Q. robur and A. vulgaris were carried out at different temperatures with water, ethanol and several hydroalcoholic mixtures. SFE of A. vulgaris was performed at different pressures and ethanol concentrations. The anti-inflammatory activity of Q. robur extracts, the antibacterial activity of A. vulgaris extracts and the antioxidant activity of the extracts from both materials were determined. The highest phenolic compound content and antioxidant activity of Q. robur extracts were achieved with water at 100 °C (487.97 mg GAE/g and 3741 µg trolox/g). The highest values for A. vulgaris extracts were obtained with ethanol at 200 °C (149.16 mg/g and 437.13 µmol/g). The ethanolic extract at 150 °C from A. vulgaris had a noticeable anti-inflammatory activity (inhibition of TNF-α and IL-6 secretion near basal values and inhibition of IL-1β higher than 80% at 20 µg/mL). A. vulgaris extracts obtained by SFE exerted antibacterial activity against E. coli (IC₅₀ of 1388 µg/mL with neat SCCO₂ at 15 MPa) and S. aureus (1406 µg/mL using SCCO₂ with 10% ethanol). Full article

Nowadays, several processes to enrich desired bioactive compounds in plant extracts have been developed. The objective of the present study was to assess the performance of bovine serum albumin in increasing the extractive yields of anthraquinones and diarylheptanoids from their respective raw plant powder extracts. Aloe emodin, rhein, emodin, and chrysophanol, from Polygonum cuspidatum, Senna alexandrina, Rhamnus frangula, and Rheum palmatum, and curcumin from Curcuma longa were analyzed in parent dry extracts, solubilized either with water, ethanol, or hydro-alcoholic mixtures, and in ones treated with aqueous solutions of bovine serum albumin by HPLC with UV/Vis detection. The different ratios between the volumes of solvents, powdered plant extracts, and bovine serum albumin were tested. The addition of albumin provided an increase in the yields of aloe emodin in the range 7.8–50.4-fold; of rhein in the range 6.1–14.1-fold; of emodin in the range 19.7–39.7-fold; of chrysophanol in the range 15.1–28.7-fold; and, finally, of curcumin of 32.1-fold. The addition of bovine serum albumin in the processing of plant extracts has been shown to be a novel and a valid alternative, comparing favourably to already reported methodologies. The easy-to-handle procedures, readily accessible facilities, and the employment of cheap substrates and reagents represent the most evident advantages of the methodology described herein. Full article

Antimicrobial resistance (AMR) is one of humanity’s main health problems today. Despite all the breakthroughs and research over the past few years, the number of microbial illnesses that are resistant to the available antibiotics is increasing at an alarming rate. In this article, we estimated the biomedical potential of Portuguese propolis harvested from the Gerês apiary over five years, evaluating the in vitro antimicrobial effect of five hydroalcoholic extracts prepared from five single propolis samples and of a hydroalcoholic extract obtained from the mixture of all samples. The antimicrobial potential was firstly assessed by determining the minimum inhibitory concentration (MIC) of these extracts against a panel of three Gram-positive (Bacillus subtilis, methicillin-sensitive Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus) and one Gram-negative bacteria (Escherichia coli), as well as two yeasts (Candida albicans and Saccharomyces cerevisiae). As MIC values against each bacterium were consistent across all the evaluated propolis extracts, we decided to further conduct a disk diffusion assay, which included three commercial antibiotics—erythromycin, vancomycin, and amoxicillin/clavulanic acid—for comparison purposes. In addition to displaying a concentration-dependent antibacterial effect, the hydroalcoholic extracts prepared with 70% ethanol exhibited stronger antimicrobial capacity than vancomycin against B. subtilis (% of increase ranged between 26 and 59%) and methicillin-sensitive S. aureus (% of increase ranged between 63 and 77%). Moreover, methicillin-resistant S. aureus (MRSA) showed susceptibility to the activity of the same extracts and resistance to all tested antibiotics. These findings support that propolis from Gerês is a promising natural product with promising antimicrobial activity, representing a very stimulating result considering the actual problem with AMR. Full article

Separating hydroalcoholic mixtures remains a significant challenge in engineering. Liquid–liquid extraction has emerged as an appealing alternative method, because it avoids the need for the large energy inputs, volatile organic compounds, and high pressures that are typically required by other separation processes. This study explores the use of hydrophobic deep eutectic solvents (HDESs) composed of terpenes and 10-undecenoic acid as extraction agents for the liquid–liquid separation of hydroalcoholic mixtures composed of alcohols (ethanol, propan-1-ol, and propan-2-ol) and water. The water content in the solvents studied was notably low, reflecting their hydrophobic nature. For the dried HDES samples, the water content ranged from 553 to 4901 ppm. In contrast, the water-saturated samples exhibited higher water contents, ranging from 7250 to 20,864 ppm. The HDES based on thymol, DL-menthol, and L-menthol displayed a eutectic point at an x_terpenes of approximately 0.67. These mixtures maintained a liquid state up to a mole fraction of terpenes around 0.75. In contrast, the HDES composed of carvacrol, fenchyl alcohol, and α-terpineol exhibited their eutectic point at an x_terpenes near 0.5. Notably, these mixtures remained in a liquid state across the entire composition range studied. The 2:1 molar ratio (HBA:HBD) presented the best values for extracting alcohols, reaching 34.04%, 36.59%, and 39.78% for ethanol, propan-2-ol, and propan-1-ol, respectively. These results show that HDES can be applied to overcome issues with existing extraction solvents, increasing the separation efficiency and making the process eco-friendly. Full article

Sulforaphane is a chiral phytochemical with chemopreventive properties. The presence of a stereogenic sulfur atom is responsible for the chirality of the natural isothiocyanate. The key role of sulfur chirality in biological activity is underscored by studies of the efficacy of individual enantiomers as chemoprotective agents. The predominant native (R) enantiomer is active, whereas the (S) antipode is inactive or has little or no biological activity. Here we provide an enantioselective high-performance liquid chromatography (HPLC) protocol for the direct and complete resolution of sulforaphane and its chiral natural homologs with different aliphatic chain lengths between the sulfinyl sulfur and isothiocyanate group, namely iberin, alyssin, and hesperin. The chromatographic separations were carried out on the immobilized-type CHIRALPAK IH-3 chiral stationary phase with amylose tris-[(S)-methylbenzylcarbamate] as a chiral selector. The effects of different mobile phases consisting of pure alcoholic solvents and hydroalcoholic mixtures on enantiomer retention and enantioselectivity were carefully investigated. Simple and environmentally friendly enantioselective conditions for the resolution of all chiral ITCs were found. In particular, pure ethanol and highly aqueous mobile phases gave excellent enantioseparations. The retention factors of the enantiomers were recorded as the water content in the aqueous-organic modifier (methanol, ethanol, or acetonitrile) mobile phases progressively varied. U-shaped retention maps were generated, indicating a dual and competitive hydrophilic interaction liquid chromatography (HILIC) and reversed-phase liquid chromatography retention mechanism on the CHIRALPAK IH-3 chiral stationary phase. Finally, experimental chiroptical studies performed in ethanol solution showed that the (R) enantiomers were eluted before the (S) counterpart under all eluent conditions investigated. Full article

The content of chemical constituents in Eugenia uniflora leaf extracts correlates positively with biological activities. The experimental objective was to carry out the phytochemical screening and purification of the major polyphenols from the leaves of E. uniflora. In addition, the anti-Candida activity of the hydroalcoholic extract, fraction, subfractions and polyphenols purified were evaluated. After partitioning of the extract with ethyl acetate, the fractions were chromatographed on Sephadex^® LH-20 gel followed by RP-flash chromatography and monitored by TLC and RP-HPLC. The samples were characterized by mass spectrometry (LC-ESI-QTOF-MS²) and subjected to the microdilution method in 96-well plates against strains of C. albicans, C. auris, and C. glabrata. Myricitrin (93.89%; w/w; m/z 463.0876), gallic acid (99.9%; w/w; m/z 169.0142), and ellagic acid (94.2%; w/w; m/z 300.9988) were recovered. The polyphenolic fraction (62.67% (w/w) myricitrin) and the ellagic fraction (67.86% (w/w) ellagic acid) showed the best antifungal performance (MIC between 62.50 and 500 μg/mL), suggesting an association between the majority constituents and the antifungal response of E. uniflora derivatives. However, there is a clear dependence on the presence of the complex chemical mixture. In conclusion, chromatographic strategies were effectively employed to recover the major polyphenols from the leaves of the species. Full article

Stevia rebaudiana Bertoni, a no-calorie natural sweetener, contains a plethora of polyphenols that exert antioxidant properties with potential medicinal significance. Due to the variety of functional groups, polyphenols exhibit varying solubility depending on the nature of the extraction solvents (water, organic, or their mixtures, defined further on as hydroalcoholic extracts). In the present study, we performed a systematic review, following PRISMA guidelines, and meta-analysis, synthesizing all available data from 45 articles encompassing 250 different studies. Our results showed that the total phenolic content (TPC) of hydroalcoholic and aqueous extracts presents higher values (64.77 and 63.73 mg GAE/g) compared to organic extracts (33.39). Total flavonoid content (TFC) was also higher in aqueous and hydroalcoholic extracts; meta-regression analysis revealed that outcomes in different measuring units (mg QE/g, mg CE/g, and mg RUE/g) do not present statistically significant differences and can be synthesized in meta-analysis. Using meta-regression analysis, we showed that outcomes from the chemical-based ABTS, FRAP, and ORAC antioxidant assays for the same extract type can be combined in meta-analysis because they do not differ statistically significantly. Meta-analysis of ABTS, FRAP, and ORAC assays outcomes revealed that the antioxidant activity profile of various extract types follows that of their phenolic and flavonoid content. Using regression meta-analysis, we also presented that outcomes from SOD, CAT, and POX enzymatic antioxidant assays are independent of the assay type (p-value = 0.905) and can be combined. Our study constitutes the first effort to quantitatively and statistically synthesize the research results of individual studies using all methods measuring the antioxidant activity of stevia leaf extracts. Our results, in light of evidence-based practice, uncover the need for a broadly accepted, unified, methodological strategy to perform antioxidant tests, and offer documentation that the use of ethanol:water 1:1 mixtures or pure water can more efficiently extract stevia antioxidant compounds. Full article

Phenolic compounds from a hydroalcoholic extract of wet olive pomace were purified and concentrated by an integrated membrane process in organic media. First, UF010104 (Solsep BV) and UP005 (Microdyn Nadir) membranes were tested to be implemented in the ultrafiltration stage, with the aim of purifying the extract and obtaining a permeate enriched in phenolic compounds. Despite the high flux observed with the UF010104 membrane (20.4 ± 0.7 L·h⁻¹·m⁻², at 2 bar), the UP005 membrane was selected because of a more suitable selectivity. Even though some secoiridoids were rejected, the permeate stream obtained with this membrane contained high concentrations of valuable simple phenols and phenolic acids, whereas sugars and macromolecules were retained. Then, the ultrafiltration permeate was subjected to a nanofiltration step employing an NF270 membrane (DuPont) for a further purification and fractionation of the phenolic compounds. The permeate flux was 50.2 ± 0.2 L·h⁻¹·m⁻², working at 15 bar. Hydroxytyrosol and some phenolic acids (such as vanillic acid, caffeic acid, and ferulic acid) were recovered in the permeate, which was later concentrated by reverse osmosis employing an NF90 membrane. The permeate flux obtained with this membrane was 15.3 ± 0.3 L·h⁻¹·m⁻². The concentrated phenolic mixture that was obtained may have important applications as a powerful antioxidant and for the prevention of diabetes and neurodegenerative diseases. Full article

Green chemistry emphasizes the isolation of biologically active compounds from plants and biomass to produce renewable, bio-based products and materials through sustainability and circularity-driven innovation processes. In this work, we have investigated the extraction of rosmarinic acid (RA), a phenolic acid with several biological properties, from aromatic herbs using ultrasounds and low environmental risk natural deep eutectic solvents (NADES). Various solvent mixtures have been investigated, and the parameters influencing the process have been studied by a mixture-process experimental design to identify the optimal RA extraction conditions. The extraction yield has been calculated by HPLC-diode array analysis. The lactic acid:ethylene glycol mixture using an ultrasound-assisted process has been found to be the most versatile solvent system, giving RA yields 127–160% higher than hydroalcoholic extraction (70% ethanol). The deep eutectic solvent nature of lactic acid:ethylene glycol has been demonstrated for the first time by multi-technique characterization (¹H-NMR and ¹³C-NMR, DSC, and W absorption properties). The aqueous raw extract has been directly incorporated into poly(vinyl alcohol) to obtain films with potential antibacterial properties for applications in the field of food and pharmaceutical packaging. Full article

This work provides insights into the possibility of integrating recovered volatile fatty acids (VFAs) into biological nitrogen removal processes. VFAs are the main products of the acidogenic fermentation of waste sludge and are an effective carbon source for denitrification in activated sludge processes. The assessment of denitrification rates and the utilisation hierarchy of different VFAs are relevant to evaluating the possibility of replacing external carbon sources with the fermented liquid, FL, from acidogenic fermentation. To this scope, single VFAs, FL collected from a full-scale waste sludge fermenter, and commercial hydroalcoholic solutions have been tested with manometric lab-scale tests. Regarding single acids, acetic acid showed the highest denitrification rates, up to 4 mg N-NO₃ g VSS⁻¹ h⁻¹, while more complex acids usually showed a lower denitrification rate. The synthetic VFA mixture and FL showed a higher denitrification rate than the sole acetate (up to 134% of the acetate denitrification rate). Mass balances across the full-scale wastewater treatment plant demonstrated the positive role of FL dosage in enhancing the denitrification process in the activated sludge treatment, with an average nitrogen removal equal to 57% and 78% without and with FL dosage, respectively. Batch manometric tests proved to be an efficient and reliable tool to assess the quality of the carbon sources as well as the activity of denitrifying bacteria in activated sludge samples. Full article

Strychnine (STCN) has demonstrated an exceptional anticancer effect against various cancers. However, the STCN clinical utility has been hampered by its low water solubility, restricted therapeutic window, short half-life, and significant toxicity. The objective of this investigation was to design and optimize a formulation of strychnine-loaded transliposomes (STCN–TLs) for dermal administration of STCN to treat skin cancer. The formulations of STCN–TL were examined in terms of vesicle size (VS), polydispersity index (PDI), entrapment efficiency (EE), and in vitro delivery. The improved STCN–TL formulation exhibited VS, PDI, EE, and in vitro delivery of 101.5 ± 2.14 nm, 0.218 ± 0.12, 81.74 ± 1.43%, and 85.39 ± 2.33%, respectively. In an ex vivo penetration, the created STCN–TL formulation demonstrated a 2.5-fold increase in permeability compared to the STCN solution. CLSM pictures of skin (rat) revealed that the rhodamine B-loaded transliposome preparation penetrated deeper than the rhodamine B hydroalcoholic mixture. Additionally, rat skin managed with STCN–TL nanogel exhibited a significant increase in C_{skin max} and AUC_0-8 compared to rat skin treated with traditional STCN gel. The findings demonstrated that the transliposome preparation might be a suitable nanocarrier for the cutaneous distribution of STCN in the amelioration of skin cancer. Full article

Respiratory viral infections continue to pose significant challenges, particularly for more susceptible and immunocompromised individuals. Nutraceutical strategies have been proposed as promising strategies to mitigate their impact and improve public health. In the present study, we developed a mixture of two hydroalcoholic extracts from the aerial parts of Echinacea purpurea (L.) Moench (ECP) and the cones of Humulus lupulus L. (HOP) that can be harnessed in the prevention and treatment of viral respiratory diseases. The ECP/HOP mixture (named ECHOPvir) was characterized for the antioxidant and cytoprotective properties in airway cells. Moreover, the immunomodulating properties of the mixture in murine macrophages against antioxidant and inflammatory stimuli and its antiviral efficacy against the PR8/H1N1 influenza virus were assayed. The modulation of the Nrf2 was also investigated as a mechanistic hypothesis. The ECP/HOP mixture showed a promising multitarget bioactivity profile, with combined cytoprotective, antioxidant, immunomodulating and antiviral activities, likely due to the peculiar phytocomplexes of both ECP and HOP, and often potentiated the effect of the single extracts. The Nrf2 activation seemed to trigger these cytoprotective properties and suggest a possible usefulness in counteracting the damage caused by different stressors, including viral infection. Further studies may strengthen the interest in this product and underpin its future nutraceutical applications. Full article

Enhanced solvent extraction (ESE) and pressurized liquid extraction (PLE) have been used for the first time to obtain antioxidant compounds from Prestonia mollis leaves. The effects of pressure (100–250 bar), temperature (55–75 °C) and the composition of the extraction solvent (ethanol, water and hydroalcoholic mixtures) were evaluated according to multilevel factorial designs. PLE provided the largest extraction yields compared to ESE, as well as a greater impact of the operating conditions studied. The highest total phenolic content was obtained when using a hydroalcoholic mixture (CO₂/ethanol/water 50/25/25) through ESE at 100 bar and 75 °C. The antioxidant capacity of this extract is related to higher concentration levels of the identified flavonoids: Quercetin 3-O-xylosyl-rutinoside, Kaempferol 3-(2G-apiosylrobinobioside) and Kaempferol 4′-glucoside 7-rhamnoside. This extract was tested for the supercritical impregnation of polylactic acid (PLA), which is a polymer widely used in the biomedical industry. The influence of pressure (100–400 bar), temperature (35–55 °C), amount of extract (3–6 mL) and impregnation time (1–2 h) have been evaluated. The best results were obtained by impregnating 3 mL of extract at 100 bar and 55 °C for 2 h, achieving 10% inhibition with DPPH methods. The extract presented a potentially suitable impregnation of PLA for biomedical applications. Full article