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Keywords = hydroxylated minor compounds

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11 pages, 3422 KiB  
Article
Insights into the Metabolism, Disposition, and Quantitative Profile of mGlu5 NAM AE90015 with Metabolite Identification and a Novel Integration Method
by Zhiyang Zack Zou, Ming-Jie Han, Yu Chang and Guiying Li
Molecules 2024, 29(23), 5724; https://doi.org/10.3390/molecules29235724 - 4 Dec 2024
Viewed by 890
Abstract
AE90015 is a highly specific and effective negative allosteric modulator (NAM) for the human mGlu5 receptor, showing significant promise for treating Parkinson’s disease. An in vivo rat oral dose study was conducted on AE90015, which involved the collection of urine and bile samples [...] Read more.
AE90015 is a highly specific and effective negative allosteric modulator (NAM) for the human mGlu5 receptor, showing significant promise for treating Parkinson’s disease. An in vivo rat oral dose study was conducted on AE90015, which involved the collection of urine and bile samples over a 24 h period. At the study’s endpoint, plasma, liver, brain, and renal tissues were also collected. A total of 30 metabolites of AE90015 were identified and structurally characterized or detected using high-resolution LC-MS/MSn. These metabolites fall into four categories: mono-hydroxyl, di-hydroxyl, mono-hydroxyl glucuronide, and di-hydroxyl glucuronide. This study provided a comprehensive overview of the metabolism, excretion, and disposition of AE90015, a promising NAM. The primary clearance pathway for AE90015 is mono-oxidation, accounting for 96% of the total, while direct excretion via renal and bile routes accounted for only 0.5%. Bile emerged as the predominant excretion route, at 65%, for metabolites and a minor amount of parent compound, which contrasts with the common assumption that urine would be the primary excretion pathway, which accounted for 26%. Each adamantyl and pyrazine moiety of AE90015 undergoes a one-time oxidation, while the pyridyl portion remains unmetabolized. Secondary metabolites, such as di-hydroxylated forms and glucuronide conjugates, do not contribute to clearance. In this work, a new quantification method combining UV and mass spectra integration was developed, allowing for the quantification of overlapping metabolite peaks. This novel approach proved to be highly effective for metabolite identification in early preclinical studies. Full article
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30 pages, 1618 KiB  
Review
Unveiling the Potential of Phytocannabinoids: Exploring Marijuana’s Lesser-Known Constituents for Neurological Disorders
by Balapal S. Basavarajappa and Shivakumar Subbanna
Biomolecules 2024, 14(10), 1296; https://doi.org/10.3390/biom14101296 - 13 Oct 2024
Cited by 3 | Viewed by 3492
Abstract
Cannabis sativa is known for producing over 120 distinct phytocannabinoids, with Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD) being the most prominent, primarily in their acidic forms. Beyond Δ9-THC and CBD, a wide array of lesser-known phytocannabinoids, along with [...] Read more.
Cannabis sativa is known for producing over 120 distinct phytocannabinoids, with Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD) being the most prominent, primarily in their acidic forms. Beyond Δ9-THC and CBD, a wide array of lesser-known phytocannabinoids, along with terpenes, flavonoids, and alkaloids, demonstrate diverse pharmacological activities, interacting with the endocannabinoid system (eCB) and other biological pathways. These compounds, characterized by phenolic structures and hydroxyl groups, possess lipophilic properties, allowing them to cross the blood–brain barrier (BBB) effectively. Notably, their antioxidant, anti-inflammatory, and neuro-modulatory effects position them as promising agents in treating neurodegenerative disorders. While research has extensively examined the neuropsychiatric and neuroprotective effects of Δ9-THC, other minor phytocannabinoids remain underexplored. Due to the well-established neuroprotective potential of CBD, there is growing interest in the therapeutic benefits of non-psychotropic minor phytocannabinoids (NMPs) in brain disorders. This review highlights the emerging research on these lesser-known compounds and their neuroprotective potential. It offers insights into their therapeutic applications across various major neurological conditions. Full article
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30 pages, 5739 KiB  
Article
In Vitro Metabolism and Transport Characteristics of Zastaprazan
by Min Seo Lee, Jihoon Lee, Minyoung Pang, John Kim, Hyunju Cha, Banyoon Cheon, Min-Koo Choi, Im-Sook Song and Hye Suk Lee
Pharmaceutics 2024, 16(6), 799; https://doi.org/10.3390/pharmaceutics16060799 - 13 Jun 2024
Cited by 6 | Viewed by 2699
Abstract
Zastaprazan (JP-1366), a novel potassium-competitive acid blocker, is a new drug for the treatment of erosive esophagitis. JP-1366 is highly metabolized in human, mouse, and dog hepatocytes but moderately metabolized in rat and monkey hepatocytes when estimated from the metabolic stability of this [...] Read more.
Zastaprazan (JP-1366), a novel potassium-competitive acid blocker, is a new drug for the treatment of erosive esophagitis. JP-1366 is highly metabolized in human, mouse, and dog hepatocytes but moderately metabolized in rat and monkey hepatocytes when estimated from the metabolic stability of this compound in hepatocyte suspension and when 18 phase I metabolites and 5 phase II metabolites [i.e., N-dearylation (M6), hydroxylation (M1, M19, M21), dihydroxylation (M7, M8, M14, M22), trihydroxylation (M13, M18), hydroxylation and reduction (M20), dihydroxylation and reduction (M9, M16), hydrolysis (M23), hydroxylation and glucuronidation (M11, M15), hydroxylation and sulfation (M17), dihydroxylation and sulfation (M10, M12), N-dearylation and hydroxylation (M3, M4), N-dearylation and dihydroxylation (M5), and N-dearylation and trihydroxylation (M2)] were identified from JP-1366 incubation with the hepatocytes from humans, mice, rats, dogs, and monkeys. Based on the cytochrome P450 (CYP) screening test and immune-inhibition analysis with CYP antibodies, CYP3A4 and CYP3A5 played major roles in the metabolism of JP-1366 to M1, M3, M4, M6, M8, M9, M13, M14, M16, M18, M19, M21, and M22. CYP1A2, 2C8, 2C9, 2C19, and 2D6 played minor roles in the metabolism of JP-1366. UDP-glucuronosyltransferase (UGT) 2B7 and UGT2B17 were responsible for the glucuronidation of M1 to M15. However, JP-1366 and active metabolite M1 were not substrates for drug transporters such as organic cation transporter (OCT) 1/2, organic anion transporter (OAT) 1/3, organic anion transporting polypeptide (OATP)1B1/1B3, multidrug and toxic compound extrusion (MATE)1/2K, P-glycoprotein (P-gp), and breast cancer-resistant protein (BCRP). Only M1 showed substrate specificity for P-gp. The findings indicated that drug-metabolizing enzymes, particularly CYP3A4/3A5, may have a significant role in determining the pharmacokinetics of zastaprazan while drug transporters may only have a small impact on the absorption, distribution, and excretion of this compound. Full article
(This article belongs to the Section Pharmacokinetics and Pharmacodynamics)
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17 pages, 3324 KiB  
Article
Effects of Thermosonication on the Antioxidant Capacity and Physicochemical, Bioactive, Microbiological, and Sensory Qualities of Blackcurrant Juice
by Xiaokun Qiu, Jiajia Su, Jiangli Nie, Zhuo Zhang, Junhan Ren, Shiyi Wang, Yi Pei and Xihong Li
Foods 2024, 13(5), 809; https://doi.org/10.3390/foods13050809 - 6 Mar 2024
Cited by 11 | Viewed by 1820
Abstract
This study investigated the effects of thermosonication (TS) on the quality of blackcurrant juice, along with its physicochemical properties, bioactive compounds, antioxidant capacity, and microbiological and sensory qualities. The treatments included raw juice (RJ), pasteurized juice (90 °C, 1 min, PJ), and thermosonicated [...] Read more.
This study investigated the effects of thermosonication (TS) on the quality of blackcurrant juice, along with its physicochemical properties, bioactive compounds, antioxidant capacity, and microbiological and sensory qualities. The treatments included raw juice (RJ), pasteurized juice (90 °C, 1 min, PJ), and thermosonicated juice (480 W, 40 kHz at 40, 50, or 60 °C, for 10, 20, 30, or 40 min, TJ). The results indicated that the effects of pasteurization and thermosonication on the pH, total soluble solids, and titratable acidity of the juice were not significant (p > 0.05). However, the cloudiness, browning index, and viscosity were significantly increased (p < 0.05), and the color properties of the blackcurrant juice were improved. The total phenolic, flavonoid, and anthocyanin contents of TJ (treated at 50 °C for 30 min) were increased by 12.6%, 20.9%, and 40.4%, respectively, and there was a notable decline in ascorbic acid content after the pasteurization treatment, while the loss was minor in all TJ samples compared with RJ. The scavenging ability of 1,1-diphenyl-2-pyridyl and hydroxyl radicals increased to 52.77% and 50.52%, respectively, which were significantly (p < 0.05) higher than those in the RJ and PJ samples. In addition, both pasteurization and thermosonication resulted in a significant (p < 0.05) reduction in microbial counts, while there were no significant (p > 0.05) differences in the sensory parameters compared with the RJ samples. In conclusion, this study suggests that TS is an effective method that can be used as an alternative to pasteurization to improve the quality of blackcurrant juice. Full article
(This article belongs to the Special Issue Functional Properties of Foods and Beverages)
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14 pages, 2891 KiB  
Article
Size Distribution and Secondary Formation of Particulate Organic Nitrates in Winter in a Coastal Area
by Ayesha Shakoor, Xinfeng Wang, Jing Chen, Yiheng Liang, Sajid Kamal, Jawad Ali, Jabir Hussain Syed, Likun Xue and Wenxing Wang
Sustainability 2023, 15(24), 16776; https://doi.org/10.3390/su152416776 - 13 Dec 2023
Viewed by 1817
Abstract
Understanding the size distribution, variation patterns, and potential formation mechanisms of particulate organic nitrates (PONs) is crucial for assessing their influences on atmospheric chemistry, air quality, and the regional climate. This study investigates PONs in the coastal atmosphere of Qingdao, China by collecting [...] Read more.
Understanding the size distribution, variation patterns, and potential formation mechanisms of particulate organic nitrates (PONs) is crucial for assessing their influences on atmospheric chemistry, air quality, and the regional climate. This study investigates PONs in the coastal atmosphere of Qingdao, China by collecting size-resolved particulate matter samples and analyzing six types of organic nitrates, namely pinene keto nitrate (PKN229), monoterpene hydroxyl nitrate (MHN215), monoterpene dicarbonyl nitrate (MDCN247), oleic acid hydroxyl nitrate (OAHN361), oleic acid keto nitrate (OAKN359), and pinene sulfate organic nitrate (PSON295), using ultrahigh-performance liquid chromatography(mass spectrometry). The mean total concentration of organic nitrates in fine particles reaches 677 ng m−3. The predominant compound is MHN215, followed by PKN229 and MDCN247. All six organic nitrates exhibited distinct concentration peaks in the droplet mode, with MDCN247 and OAHN361 showing a minor peak in the condensation mode. In addition, an apparent concentration peak is observed in the coarse mode for OAKN359. Comparative analyses under various conditions highlight the significant influences of primary emissions and secondary formation processes on the abundance and size distribution of organic nitrates. For instance, both firework displays during festivals and high NOx emissions from fuel combustion significantly increase the concentrations of condensation-mode organic nitrates, whereas dust particles enhanced the heterogeneous formation of coarse-mode particles. Furthermore, the high humidity of the coastal area promotes aqueous formation in droplet-mode particles. Full article
(This article belongs to the Section Air, Climate Change and Sustainability)
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14 pages, 1490 KiB  
Article
An Untargeted Metabolomics Approach to Study the Variation between Wild and Cultivated Soybeans
by Fakir Shahidullah Tareq, Raghavendhar R. Kotha, Savithiry Natarajan, Jianghao Sun and Devanand L. Luthria
Molecules 2023, 28(14), 5507; https://doi.org/10.3390/molecules28145507 - 19 Jul 2023
Cited by 6 | Viewed by 2455
Abstract
The differential metabolite profiles of four wild and ten cultivated soybeans genotypes were explored using an untargeted metabolomics approach. Ground soybean seed samples were extracted with methanol and water, and metabolic features were obtained using ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry [...] Read more.
The differential metabolite profiles of four wild and ten cultivated soybeans genotypes were explored using an untargeted metabolomics approach. Ground soybean seed samples were extracted with methanol and water, and metabolic features were obtained using ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS) in both positive and negative ion modes. The UHPLC-HRMS analysis of the two different extracts resulted in the putative identification of 98 metabolites belonging to several classes of phytochemicals, including isoflavones, organic acids, lipids, sugars, amino acids, saponins, and other compounds. The metabolic profile was significantly impacted by the polarity of the extraction solvent. Multivariate analysis showed a clear difference between wild and cultivated soybean cultivars. Unsupervised and supervised learning algorithms were applied to mine the generated data and to pinpoint metabolites differentiating wild and cultivated soybeans. The key identified metabolites differentiating wild and cultivated soybeans were isoflavonoids, free amino acids, and fatty acids. Catechin analogs, cynaroside, hydroxylated unsaturated fatty acid derivatives, amino acid, and uridine diphosphate-N-acetylglucosamine were upregulated in the methanol extract of wild soybeans. In contrast, isoflavonoids and other minor compounds were downregulated in the same soybean extract. This metabolic information will benefit breeders and biotechnology professionals to develop value-added soybeans with improved quality traits. Full article
(This article belongs to the Section Food Chemistry)
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19 pages, 4858 KiB  
Article
Interaction of Redox-Active Copper(II) with Catecholamines: A Combined Spectroscopic and Theoretical Study
by Miriama Šimunková, Zuzana Barbieriková, Milan Mazúr, Marian Valko, Suliman Y. Alomar, Saleh H. Alwasel and Michal Malček
Inorganics 2023, 11(5), 208; https://doi.org/10.3390/inorganics11050208 - 12 May 2023
Cited by 2 | Viewed by 2275
Abstract
In this work, attention is focused on the non-essential amino acid L-Tyrosine (TYR) hydroxylated to L-DOPA, which is the precursor to the neurotransmitters dopamine, noradrenaline (norepinephrine; NE) and adrenaline (epinephrine; EP) known as catecholamines and their interactions with redox-active Cu(II). Catecholamines have multiple [...] Read more.
In this work, attention is focused on the non-essential amino acid L-Tyrosine (TYR) hydroxylated to L-DOPA, which is the precursor to the neurotransmitters dopamine, noradrenaline (norepinephrine; NE) and adrenaline (epinephrine; EP) known as catecholamines and their interactions with redox-active Cu(II). Catecholamines have multiple functions in biological systems, including the regulation of the central nervous system, and free (unbound) redox metal ions are present in many diseases with disturbed metal homeostasis. The interaction between catecholamines and Cu(II) has been studied by means of Electron Paramagnetic Resonance spectroscopy (EPR), EPR spin trapping and UV-vis spectroscopy. The obtained spectroscopic results are supported by Density Functional Theory calculations. Only minor qualitative and quantitative changes in the UV-vis spectra of all the studied compounds have been observed following their interactions with Cu(II) ions. The low-temperature EPR spectra were more convincing and confirmed the interaction between Cu(II) ions and all the studied compounds, involving hydroxyl groups and amino nitrogens. The use of an ABTS assay revealed that the compounds under study possessed radical-scavenging activities against ABTS•+ in the order TYR < EP < DA < NE~L-DOPA. The neurotransmitters DA, NE and EP, following their interaction with Cu(II), exhibit the ability to (partially) reduce Cu(II) to Cu(I) species which was confirmed using the Cu(I) specific chelator neocuproine. EPR spin-trapping experiments revealed the suppressed formation of hydroxyl radicals (OH) in a copper(II) catalyzed Fenton-like system in the presence of catecholamines. Only in the case of EP was autooxidation in a stock solution observed. Furthermore, the oxidation of EP is enhanced in the presence of Cu(II) ions. In conclusion, it has been confirmed that the oxidation of catecholamines in the presence of copper promotes the redox cycling process, resulting in the formation of ROS, which may, in turn, cause damage to neuronal systems. Full article
(This article belongs to the Special Issue 10th Anniversary of Inorganics: Bioinorganic Chemistry)
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13 pages, 2154 KiB  
Article
Ketonization of Ginsenoside C-K by Novel Recombinant 3-β-Hydroxysteroid Dehydrogenases and Effect on Human Fibroblast Cells
by Yan Jin, Dandan Wang, Wan-Taek Im, Muhammad Zubair Siddiqi and Deok-Chun Yang
Molecules 2023, 28(9), 3792; https://doi.org/10.3390/molecules28093792 - 28 Apr 2023
Cited by 3 | Viewed by 1955
Abstract
Background and objective: The ginsenoside compound K (C-K) (which is a de-glycosylated derivative of major ginsenosides) is effective in the treatment of cancer, diabetes, inflammation, allergy, angiogenesis, aging, and has neuroprotective, and hepatoprotective than other minor ginsenosides. Thus, a lot of studies have [...] Read more.
Background and objective: The ginsenoside compound K (C-K) (which is a de-glycosylated derivative of major ginsenosides) is effective in the treatment of cancer, diabetes, inflammation, allergy, angiogenesis, aging, and has neuroprotective, and hepatoprotective than other minor ginsenosides. Thus, a lot of studies have been focused on the conversion of major ginsenosides to minor ginsenosides using glycoside hydrolases but there is no study yet published for the bioconversion of minor ginsenosides into another high pharmacological active compound. Therefore, the objective of this study to identify a new gene (besides the glycoside hydrolases) for the conversion of minor ginsenosides C-K into another highly pharmacological active compound. Methods and Results: Lactobacillus brevis which was isolated from Kimchi has showed the ginsenoside C-K altering capabilities. From this strain, a novel potent decarboxylation gene, named HSDLb1, was isolated and expressed in Escherichia coli BL21 (DE3) using the pMAL-c5X vector system. Recombinant HSDLb1 was also characterized. The HSDLb1 consists of 774 bp (258 amino acids residues) with a predicted molecular mass of 28.64 kDa. The optimum enzyme activity was recorded at pH 6.0–8.0 and temperature 30 °C. Recombinant HSDLb1 effectively transformed the ginsenoside C-K to 12-β-hydroxydammar-3-one-20(S)-O-β-D-glucopyranoside (3-oxo-C-K). The experimental data proved that recombinant HSDLb1 strongly ketonized the hydroxyl (-O-H) group at C-3 of C-K via the following pathway: C-K → 3-oxo-C-K. In vitro study, 3-oxo-C-K showed higher solubility than C-K, and no cytotoxicity to fibroblast cells. In addition, 3-oxo-C-K induced the inhibitory activity of ultraviolet A (UVA) against matrix metalloproteinase-1 (MMP-1) and promoted procollagen type I synthesis. Based on these expectations, we hypothesized that 3-oxo-C-K can be used in cosmetic products to block UV radiations and anti-ageing agent. Furthermore, we expect that 3-oxo-C-K will show higher efficacy than C-K for the treatment of cancer, ageing and other related diseases, for which more studies are needed. Full article
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19 pages, 6017 KiB  
Article
Olive Polyphenol Oxidase Gene Family
by Rosario Sánchez, Laura Arroyo, Pilar Luaces, Carlos Sanz and Ana G. Pérez
Int. J. Mol. Sci. 2023, 24(4), 3233; https://doi.org/10.3390/ijms24043233 - 6 Feb 2023
Cited by 9 | Viewed by 2649
Abstract
The phenolic compounds containing hydroxytyrosol are the minor components of virgin olive oil (VOO) with the greatest impact on its functional properties and health benefits. Olive breeding for improving the phenolic composition of VOO is strongly dependent on the identification of the key [...] Read more.
The phenolic compounds containing hydroxytyrosol are the minor components of virgin olive oil (VOO) with the greatest impact on its functional properties and health benefits. Olive breeding for improving the phenolic composition of VOO is strongly dependent on the identification of the key genes determining the biosynthesis of these compounds in the olive fruit and also their transformation during the oil extraction process. In this work, olive polyphenol oxidase (PPO) genes have been identified and fully characterized in order to evaluate their specific role in the metabolism of hydroxytyrosol-derived compounds by combining gene expression analysis and metabolomics data. Four PPO genes have been identified, synthesized, cloned and expressed in Escherichia coli, and the functional identity of the recombinant proteins has been verified using olive phenolic substrates. Among the characterized genes, two stand out: (i) OePPO2 with its diphenolase activity, which is very active in the oxidative degradation of phenols during oil extraction and also seems to be highly involved in the natural defense mechanism in response to biotic stress, and (ii) OePPO3, which codes for a tyrosinase protein, having diphenolase but also monophenolase activity, which catalyzes the hydroxylation of tyrosol to form hydroxytyrosol. Full article
(This article belongs to the Special Issue State-of-the-Art Molecular Plant Biology Research in Spain)
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18 pages, 4575 KiB  
Article
Composition and Structure of Aspen (Pópulus trémula) Hemicelluloses Obtained by Oxidative Delignification
by Valentina S. Borovkova, Yuriy N. Malyar, Irina G. Sudakova, Anna I. Chudina, Dmitriy V. Zimonin, Andrey M. Skripnikov, Angelina V. Miroshnikova, Vladislav A. Ionin, Alexander S. Kazachenko, Valentin V. Sychev, Ilya S. Ponomarev and Noureddine Issaoui
Polymers 2022, 14(21), 4521; https://doi.org/10.3390/polym14214521 - 25 Oct 2022
Cited by 17 | Viewed by 2755
Abstract
In this study, hemicelluloses of aspen wood (Pópulus trémula) were obtained by oxidative delignification in an acetic acid-water-hydrogen peroxide medium at temperatures of 70–100 °C and a process time of 1–4 h. The maximum polysaccharide yield of up to 9.68 wt% [...] Read more.
In this study, hemicelluloses of aspen wood (Pópulus trémula) were obtained by oxidative delignification in an acetic acid-water-hydrogen peroxide medium at temperatures of 70–100 °C and a process time of 1–4 h. The maximum polysaccharide yield of up to 9.68 wt% was reported. The composition and structure of the hemicelluloses were studied using a complex of physicochemical methods: gas and gel permeation chromatography, Fourier-transform infrared spectroscopy, 2D nuclear magnetic resonance spectroscopy, and thermogravimetric analysis. The xylose, mannose, galactose, and glucose monomer units were identified in the hemicelluloses by gas chromatography. The weight average molecular weight Mw of the products determined by gel permeation chromatography was found to range within 8932–33,142 g/mol. The reported Fourier-transform spectra of the hemicelluloses contain all the bands characteristic of heteropolysaccharides; a weak lignin absorption signal in the spectra at 1500–1510 cm−1 is attributed to a minor content of phenolic fragments in the structure of the obtained hemicelluloses. The use of thermogravimetric analysis established that the hemicelluloses isolated from aspen wood are resistant against heating to temperatures of up to 90–100 °C and, upon further heating up to 400 °C, start destructing at an increasing rate. The antioxidant activity of the hemicelluloses was examined using the compounds that mimic free radicals (1,1-diphenyl-2-picrylhydrazyl) and hydroxyl radicals (salicylic acid). It was found that the activity of all polysaccharides in neutralizing DPPH and hydroxyl radicals is lower than the absorption capacity of vitamin C at all the tested concentrations (0.5, 2, and 5 mg/mL) and attains 81.7 and 82.9%, respectively. Full article
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2 pages, 175 KiB  
Abstract
A Simplified SPE-GC-FID Method for Detection of Adulteration of Olive Oil with Sunflower Oil
by Paolo Lucci, Enrico Valli, Andrea Milani, Ana Srbinovska, Erica Moret, Sabrina Moret, Alessandra Bendini, Wenceslao Moreda and Tullia Gallina Toschi
Biol. Life Sci. Forum 2022, 18(1), 21; https://doi.org/10.3390/Foods2022-12973 - 30 Sep 2022
Viewed by 1005
Abstract
The unique distribution of free and esterified minor compounds represents a promising tool for the evaluation of olive oil authenticity. For this purpose, we developed and in-house validated a simple SPE-GC-FID method for the determination of ratio patterns in free and esterified hydroxylated [...] Read more.
The unique distribution of free and esterified minor compounds represents a promising tool for the evaluation of olive oil authenticity. For this purpose, we developed and in-house validated a simple SPE-GC-FID method for the determination of ratio patterns in free and esterified hydroxylated minor compounds of olive and sunflower oils. The methodology showed suitable repeatability relative standard deviation, which was lower than 7.5% in all cases. The method, which is intentionally based on simple instrumentations, allows the quantification of hydroxylated minor compounds in a single chromatographic run while reducing sample preparation, the employment of toxic solvents, and analysis time. Finally, the analytical approach has been used for the analysis of pure oil samples, comprising 15 authentic extra-virgin olive oils selected from different European countries, revealing different hydroxylated minor compounds profiles and the proportion of free and esterified forms in olive and sunflower oils. The SPE-GC-FID method proposed herein has been applied to the quantification of free and esterified hydroxylated minor compounds as well as their ratio in pure extra virgin olive oil mixed in different amounts to mimic olive oil adulteration with refined sunflower oil at different levels of 2, 5, 10, 15, and 20% (w/w). As a result, even the smaller addition of 2% of sunflower oil in extra-virgin olive oil led to a significant decrease in the free/esterified hydroxylated minor components ratio. This work was developed in the context of the project OLEUM ‘Advanced solutions for assuring authenticity and quality of olive oil at global scale’ funded by the European Commission within the Horizon 2020 Programme (2014-2020, GA no. 635690). The information expressed in this abstract reflects the authors’ views; the EC is not liable for the information contained therein. Full article
17 pages, 3111 KiB  
Article
Exudates of Picea abies, Pinus nigra, and Larix decidua: Chromatographic Comparison and Pro-Migratory Effects on Keratinocytes In Vitro
by Thomas Goels, Elisabeth Eichenauer, Ammar Tahir, Paul Prochaska, Franziska Hoeller, Elke H. Heiß and Sabine Glasl
Plants 2022, 11(5), 599; https://doi.org/10.3390/plants11050599 - 23 Feb 2022
Cited by 12 | Viewed by 3506
Abstract
Balms and resins of Picea abies, Larix decidua, and Pinus nigra are traditionally used to treat wounds. Three chromatographic techniques differing in separation capacity and technical demands were employed to distinguish among these plant exudates. A TLC method was established for [...] Read more.
Balms and resins of Picea abies, Larix decidua, and Pinus nigra are traditionally used to treat wounds. Three chromatographic techniques differing in separation capacity and technical demands were employed to distinguish among these plant exudates. A TLC method was established for fingerprint comparison, providing a quick overview of a large number of samples at low cost. HPLC-DAD (RP18) and UHPSFC-DAD (Torus 2-Picolylamin), hyphenated to ESI-MS, represented orthogonal chromatographic systems with high separation performance. The developed methods allow for the separation and detection of major and minor constituents belonging to different compound classes (phenyl carboxylic acids, lignans, diterpene resin acids). The qualitative compositions of the diterpene resin acids, the main compounds in the exudates, were comparable in all three genera. Differences were detected in the distribution of hydroxylated diterpene resin acids, pinoresinol, and hydroxycinnamic acids. The three tested chromatographic systems with varying demands on lab equipment offer appropriate tools for the quality assessment of Picea abies, Larix decidua, and Pinus nigra. The extracts were furthermore tested at three different concentrations (10 µg/mL, 3 µg/mL, and 1 µg/mL) for boosted re-epithelialization, a crucial step in the wound-healing process, in an in vitro HaCaT keratinocyte-based scratch assay. Lysophosphatidic acid (LPA, 10 µM) and extracts of several medicinal plants well known for their wound-healing properties (birch, marigold, St. John’s wort, manuka honey) were used as positive controls. Picea abies and Pinus nigra showed concentration dependency; significant activity was measured for Larix decidua at 3 µg/mL. Full article
(This article belongs to the Special Issue Chemical Profiling and Biological Activity of Plant Natural Compounds)
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16 pages, 3330 KiB  
Article
Understanding the Surface Characteristics of Biochar and Its Catalytic Activity for the Hydrodeoxygenation of Guaiacol
by Indri Badria Adilina, Robert Ronal Widjaya, Luthfiana Nurul Hidayati, Edi Supriadi, Muhammad Safaat, Ferensa Oemry, Elvi Restiawaty, Yazid Bindar and Stewart F. Parker
Catalysts 2021, 11(12), 1434; https://doi.org/10.3390/catal11121434 - 25 Nov 2021
Cited by 16 | Viewed by 3540
Abstract
Biochar (BCR) was obtained from the pyrolysis of a palm-oil-empty fruit bunch at 773 K for 2 h and used as a catalyst for the hydrodeoxygenation (HDO) of guaiacol (GUA) as a bio-oil model compound. Brunauer–Emmet–Teller surface area analysis, NH3 and CO [...] Read more.
Biochar (BCR) was obtained from the pyrolysis of a palm-oil-empty fruit bunch at 773 K for 2 h and used as a catalyst for the hydrodeoxygenation (HDO) of guaiacol (GUA) as a bio-oil model compound. Brunauer–Emmet–Teller surface area analysis, NH3 and CO2-temperature-programmed desorption, scanning electron microscope–dispersive X-ray spectroscopy, CHN analysis and X-ray fluorescence spectroscopy suggested that macroporous and mesoporous structures were formed in BCR with a co-presence of hydrophilic and hydrophobic sites and acid–base behavior. A combination of infrared, Raman and inelastic neutron scattering (INS) was carried out to achieve a complete vibrational assignment of BCR. The CH–OH ratio in BCR is ~5, showing that the hydroxyl functional groups are a minority species. There was no evidence for any aromatic C–H stretch modes in the infrared, but they are clearly seen in the INS and are the majority species, with a ratio of sp3–CH:sp2–CH of 1:1.3. The hydrogen bound to sp2–C is largely present as isolated C–H bonds, rather than adjacent C–H bonds. The Raman spectrum shows the characteristic G band (ideal graphitic lattice) and three D bands (disordered graphitic lattice, amorphous carbon, and defective graphitic lattice) of sp2 carbons. Adsorbed water in BCR is present as disordered layers on the surface rather than trapped in voids in the material and could be removed easily by drying prior to catalysis. Catalytic testing demonstrated that BCR was able to catalyze the HDO of GUA, yielding phenol and cresols as the major products. Phenol was produced both from the direct demethoxylation of GUA, as well as through the demethylation pathway via the formation of catechol as the intermediate followed by deoxygenation. Full article
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15 pages, 3713 KiB  
Article
An Evaluation of the Antioxidant Activity of a Methanolic Extract of Cucumis melo L. Fruit (F1 Hybrid)
by R. S. Rajasree, Sibi P. Ittiyavirah, Punnoth Poonkuzhi Naseef, Mohamed Saheer Kuruniyan, G. S. Anisree and Muhammed Elayadeth-Meethal
Separations 2021, 8(8), 123; https://doi.org/10.3390/separations8080123 - 18 Aug 2021
Cited by 14 | Viewed by 4754
Abstract
Cucumis melo L. (C. melo) is a fruit with many medicinal properties and is consumed in various countries. It is utilised for chronic eczema and to treat minor burns and scrapes. The present study was conducted to evaluate the antioxidant activity [...] Read more.
Cucumis melo L. (C. melo) is a fruit with many medicinal properties and is consumed in various countries. It is utilised for chronic eczema and to treat minor burns and scrapes. The present study was conducted to evaluate the antioxidant activity of a methanolic extract of Cucumis melo Linn (MECM). A coarse powder prepared from the fruit and seeds was extracted with methanol (absolute) by a hot continuous percolation process in accordance with the standard protocols. All the extracts were estimated for potential antioxidant activities with tests such as an estimation of total antioxidant activity, hydroxyl radical and nitric oxide scavenging activity and reducing power ability. The qualitative analysis of the methanolic extract of C. melo fruit showed the presence of various phytochemical constituents such as carbohydrates, alkaloids, sterols, phenolic compounds, terpenes and flavonoids. The total antioxidant activity of concentrations of 50, 100 and 200 µg were tested and observed to be 3.3 ± 0.1732, 6.867 ± 0.5457 and 13.63 ± 0.8295 µg of ascorbic acid, respectively. The results also showed significant nitric oxide and DPPH scavenging activities as well as a reducing power activity of MECM. Thus, our results suggest that MECM may serve as a putative source of natural antioxidants for therapeutic and nutraceutical applications. Full article
(This article belongs to the Special Issue Extraction and Analysis of Plant Active Ingredients)
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20 pages, 5236 KiB  
Article
Radiation-Induced Graft Immobilization (RIGI): Covalent Binding of Non-Vinyl Compounds on Polymer Membranes
by Martin Schmidt, Stefan Zahn, Florian Gehlhaar, Andrea Prager, Jan Griebel, Axel Kahnt, Wolfgang Knolle, Robert Konieczny, Roger Gläser and Agnes Schulze
Polymers 2021, 13(11), 1849; https://doi.org/10.3390/polym13111849 - 2 Jun 2021
Cited by 16 | Viewed by 4048
Abstract
Radiation-induced graft immobilization (RIGI) is a novel method for the covalent binding of substances on polymeric materials without the use of additional chemicals. In contrast to the well-known radiation-induced graft polymerization (RIGP), RIGI can use non-vinyl compounds such as small and large functional [...] Read more.
Radiation-induced graft immobilization (RIGI) is a novel method for the covalent binding of substances on polymeric materials without the use of additional chemicals. In contrast to the well-known radiation-induced graft polymerization (RIGP), RIGI can use non-vinyl compounds such as small and large functional molecules, hydrophilic polymers, or even enzymes. In a one-step electron-beam-based process, immobilization can be performed in a clean, fast, and continuous operation mode, as required for industrial applications. This study proposes a reaction mechanism using polyvinylidene fluoride (PVDF) and two small model molecules, glycine and taurine, in aqueous solution. Covalent coupling of single molecules is achieved by radical recombination and alkene addition reactions, with water radiolysis playing a crucial role in the formation of reactive solute species. Hydroxyl radicals contribute mainly to the immobilization, while solvated electrons and hydrogen radicals play a minor role. Release of fluoride is mainly induced by direct ionization of the polymer and supported by water. Hydrophobic chains attached to cations appear to enhance the covalent attachment of solutes to the polymer surface. Computational work is complemented by experimental studies, including X-ray photoelectron spectroscopy (XPS) and fluoride high-performance ion chromatography (HPIC). Full article
(This article belongs to the Special Issue Advances in Surface Functionalization of Polymer Nanostructures)
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