Quasi-MSn identification of flavanone 7-glycoside isomers in Da Chengqi Tang by high performance liquid chromatography-tandem mass spectrometry

<p>Abstract</p> <p>Background</p> <p><it>Da Chengqi Tang </it>(DCT) is a common purgative formula in Chinese medicine. Flavanones are its major active compounds derived from <it>Fructus Aurantii Immaturus</it>. The present study developed an LC-MS/MS method to characterize two pairs of flavanone 7-glycoside isomers, i.e., hesperidin versus neohesperidin and naringin versus isonaringin.</p> <p>Methods</p> <p>After solid phase purification, components in sample were separated on a Agilent zorbax SB-C18 (5 μm, 250 mm × 4.6 mm) analytical column. ESI-MS and quasi-MSⁿwere performed in negative ion mode to obtain structural data of these two pairs of flavanone 7-glycoside isomers. Moreover, UV absorption was measured.</p> <p>Results</p> <p>There was no intra-pairs difference in the UV-Vis and MS/MS spectra of the two pairs of 7-glycoside isomers, whereas the mass spectrometry fragmentation pathways between pairs were different.</p> <p>Conclusion</p> <p>The present study developed a LC-MS/MS method to explore the inter- and intra-pair difference of two pairs of flavanone 7-glycoside isomers.</p

Screening the effect of four ultrasound-assisted extraction parameters on hesperidin and phenolic acid content of aqueous citrus pomace extracts

Polyphenols of citrus by-products, due to their antioxidant and antimicrobial activities, could be valorized by pharmaceutical and food industries, adding a value to the citrus processing companies. A number of studies have investigated the effect of ultrasound-assisted extraction (UAE) conditions on the recovery of phenolics derived from citrus waste using both organic solvents or mixed aqueous solvent systems. To maximize efficiency, UAE conditions should be tailored to the physical parameters of the solvent(s) employed. The aim of this study was to investigate the effect of four UAE parameters: particle size (1.40–2.80 mm), extraction time (10–60 min), extraction temperature (23–50 °C) and ultrasonic power (150–250 W) on the simultaneous recovery of p-coumaric acid, caffeic acid, chlorogenic acid, and hesperidin from citrus waste using pure water as a solvent. High-performance liquid chromatography (HPLC) was employed for the identification and quantification of the cited compounds. Particle size was determined to be an important parameter affecting compound recovery, with the exception of chlorogenic acid. A particle size of 1.40 mm resulted in the highest recovery of p-coumaric and caffeic acids (0.25 and 0.58 mg/g, respectively), while higher hesperidin yields were achieved from the particle sizes of 2.00 and 1.40 mm (6.44 and 6.27 mg/g, respectively). Extraction temperature significantly affected only the recovery of the flavanone glycoside (P&lt;0.05). As the extraction temperature increased from 30 to 50 °C the recovery of hesperidin increased from 6.59 to 7.84 mg/g, respectively. Neither extraction time nor ultrasonic power significantly affected the recovery of any individual phenolic compound

Supplementary data for the article: Cirkovic Velickovic, T. D.; Stanic-Vucinic, D. J. The Role of Dietary Phenolic Compounds in Protein Digestion and Processing Technologies to Improve Their Antinutritive Properties. Comprehensive Reviews in Food Science and Food Safety 2018, 17 (1), 82–103. https://doi.org/10.1111/1541-4337.12320

Supplementary material for: [https://doi.org/10.1111/1541-4337.12320]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2074

Identification of a Bifunctional Maize C- and O-Glucosyltransferase

Flavonoids accumulate in plant vacuoles usually as O-glycosylated derivatives, but several species can also synthesize flavonoid C-glycosides. Recently, we demonstrated that a flavanone 2-hydroxylase (ZmF2H1, CYP93G5) converts flavanones to the corresponding 2-hydroxy derivatives, which are expected to serve as substrates for C-glycosylation. Here, we isolated a cDNA encoding a UDP-dependent glycosyltransferase (UGT708A6), and its activity was characterized by in vitro and in vivo bioconversion assays. In vitro assays using 2-hydroxyflavanones as substrates and in vivo activity assays in yeast co-expressing ZmF2H1 and UGT708A6 show the formation of the flavones C-glycosides. UGT708A6 can also O-glycosylate flavanones in bioconversion assays in Escherichia coli as well as by in vitro assays with the purified recombinant protein. Thus, UGT708A6 is a bifunctional glycosyltransferase that can produce both C- and O-glycosidated flavonoids, a property not previously described for any other glycosyltransferase.Fil: Falcone Ferreyra, María Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Centro de Estudios Fotosintéticos y Bioquímicos (i); ArgentinaFil: Rodriguez, Eduardo Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Casas, María Isabel. The Ohio State University. Plant Biotechnology Center. Department Plant Cell Molecular Biology; Estados UnidosFil: Labadie, Guillermo Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Química Rosario; ArgentinaFil: Grotewold, Erich. The Ohio State University. Plant Biotechnology Center; Estados UnidosFil: Casati, Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Centro de Estudios Fotosintéticos y Bioquímicos (i); Argentin

Studies on the extraction and characterization of pectin and bitter principles from New Zealand grapefruit and Philippine calamansi : a thesis presented in partial fulfilment of the requirements for the degree of Master of Technology in Food Technology at Massey University

A study was conducted to determine the presence of bitter components in NZ grapefruit and Philippine calamansi; describe the effect of maturity on the bitter components and other chemical constituents of grapefruit; reduce the bitterness of grapefruit juice by adsorption on polyvinylpyrrolidone; and to extract and characterize pectin from grapefruit peel. Naringin (995 PPm), narirutin (187 ppm), and limonoids (7.9 ppm) were detected in NZ grapefruit juice concentrate (27° Brix). Naringin was not detected in the calamansi juice, and limonin was detected at the level of 10.5 ppm in juice containing 5% crushed seeds. Maturation of the grapefruit caused an increase in pH from 3.00 to 3.50, an increase in total soluble solids from 10.8 to 14.4 with a decline to 13.5° Brix later in the season, a steady fall in acidity from 2.50 to 1.31 g citric acid/100 mL, and a continuous rise in the Brix/acid ratio from 4.2 to 10.3. Juice yield fluctuated throughout the season. Ascorbic acid remained fairly steady in the early and mid-season fruit but decreased in the late-season fruit. Naringin content was highest at the beginning of the season and fluctuated throughout the season. Naringin content in the grapefruit peel remained constant as the fruit matured. Narirutin was detected in the early-season fruit but disappeared later in the season. Limonoid content in both unpasteurized and pasteurized juices decreased with ripening. The use of polyvinylpyrrolidone significantly reduced naringin in grapefruit juice by up to 78.1% and limonin by up to 17.5% depending on the amount and reaction time of the adsorbent. A loss of 23.1% in ascorbic acid occurred with 5% PVP with a reaction time of 1 h. Pectin extraction at 85°C and the use of acidified isopropyl alcohol yielded a product with the following characteristics: 8.9% yield; 1.3% moisture content; 1.9% ash; 759 equivalent weight; 9.2% methoxyl content; 82.2% anhydrogalacturonic acid; 63.2% degree of esterification; 4.2 intrinsic viscosity; 89,362 molecular weight and setting time of 0.55 minute

Cheminformatic Approach for Deconvolution of Active Compounds in a Complex Mixture - phytoserms in Licorice

ABSTRACT After the validation of our in silico models by using the previous knowledge in this area the alerting phytochemicals from two Glycyrrhiza species (G. glabra and G. uralensis) were clustered. Exhaustive computational mining of licorice metabolome against selected endocrinal and metabolic targets led to the discovery of a unique class of compounds which belong to the dihydrostilbenoids (DHS) class appended with prenyl groups at various positions. To the best of our knowledge this interesting group of compounds has not been studied for their estrogenic activities or PXR activation. In addition some of the bis-prenylated DHS have been reported to be present only in G. uralensis. Another aspect of the current project was to predict the phase I primary metabolites of compounds found in both species of Glycyrrhiza and assess them with computational tools to predict their binding potential against both isoforms of hERs or drug metabolizing enzymes such as (CYP) inhibition models. Our investigations revealed estrogenic character for most of the predicted metabolites and have confirmed earlier reports of potential CYP3A4 and CYP1A2 inhibition. Compilation of such data is essential to gain a better understanding of the efficacy/safety of licorice extracts used in various botanical formularies. This approach with the involved cheminformatic tools has proven effective to yield rich information to support our understanding of traditional practices. It also can expand the role of botanical drugs for introducing new chemical entities (NCEs) and/or uncovering their liabilities at early stages. In this work we endeavored to comprehend the mechanism associated with the efficacy and safety of components reported in the licorice plant. We utilized smart screening techniques such as cheminformatics tools to reveal the high number of secondary metabolites produced by licorice which are capable of interfering with the human Estrogen Receptors (hERs) and/or PXR or other vital cytochrome P450 enzymes. The genus Glycyrrhiza encompasses several species exhibiting complex structural diversity of secondary metabolites and hence biological activities. The intricate nature of botanical remedies such as licorice rendered them obsolete for scientific research or medical industry. Understanding and finding the mechanisms of efficacy or safety for a plant-based therapy is very challenging yet it remains crucial and warranted. The licorice plant is known to have Selective Estrogen Receptor Modulatory effects (SERMs) with a spectrum of estrogenic and anti-estrogenic activities attributed to women’s health. On the contrary licorice extract was shown to induce pregnane xenobiotic receptor (PXR) which may manifest as a potential route for deleterious effects such as herb-drug interaction (HDI). While many studies attributed these divergent activities to a few classes of compounds such as liquiritigenin (a weak estrogenic SERM) or glycyrrhizin (weak PXR agonist) no attempt was made to characterize the complete set of compounds responsible for these divergent activities. A plethora of licorice components is undermined which might have the potential to be developed into novel phytoSERMS or to trigger undesirable adverse effects by altering drug metabolizing enzymes and thus pharmacokinetics. Thus we have ventured to synthesize a set of constitutional isomers of stilbenoids and DHS (archetypal of those found in licorice) with different prenylation patterns. Sixteen constitutional isomers of stilbenoids (M2-M10) and DHS (M12-M18) were successfully synthesized of which six of them (M8 M9 M14 M15 M17 and M18) were synthesized for the first time to be further tested and validated with cell-based methods for their estrogenic activities. We have unveiled a novel class of compounds which possess a strong PXR activation. These results which were in accord with the in silico prediction were observed for multiple synthesized prenylated stilbenoid and DHS by the luciferase reporter gene assay at µM concentrations. Moreover this activation was further validated by the six-fold increase in mRNA expression of Cytochrome P450 3A4 (CYP3A4) where three representative compounds (M7 M10 and M15) exceeded the activation fold of the positive control

Comparative flavonoid profile of orange (Citrus sinensis) flavedo and albedo extracted by conventional and emerging techniques using UPLC-IMS-MS, chemometrics and antioxidant effects

Introduction: Citrus fruits are one of the most frequently counterfeited processed products in the world. In the juice production alone, the peels, divided into flavedo and albedo, are the main waste product. The extracts of this by-product are enriched with many bioactive substances. Newer extraction techniques generally have milder extraction conditions with simultaneous improvement of the extraction process. Methods: This study presents a combinatorial approach utilizing data-independent acquisition-based ion mobility spectrometry coupled to tandem mass spectrometry. Integrating orthogonal collision cross section (CCS) data matching simultaneously improves the confidence in metabolite identification in flavedo and albedo tissues from Citrus sinensis. Furthermore, four different extraction approaches [conventional, ultrasonic, High Hydrostatic Pressure (HHP) and Pulsed Electric Field (PEF)] with various optimized processing conditions were compared in terms of antioxidant effects and flavonoid profile particularly polymethoxy flavones (PMFs). Results: A total number of 57 metabolites were identified, 15 of which were present in both flavedo and albedo, forming a good qualitative overlapping of distributed flavonoids. For flavedo samples, the antioxidant activity was higher for PEF and HHP treated samples compared to other extraction methods. However, ethyl acetate extract exhibited the highest antioxidant effects in albedo samples attributed to different qualitative composition content rather than various quantities of same metabolites. The optimum processing conditions for albedo extraction using HHP and PEF were 200 MPa and 15 kJ/kg at 10 kV, respectively. While, HHP at medium pressure (400 MPa) and PEF at 15 kJ/kg/3 kV were the optimum conditions for flavedo extraction. Conclusion: Chemometric analysis of the dataset indicated that orange flavedo can be a valid source of soluble phenolic compounds especially PMFs. In order to achieve cross-application of production, future study should concentrate on how citrus PMFs correlate with biological engineering techniques such as breeding, genetic engineering, and fermentation engineering

Bioactive flavanoids from Glycosmis arborea

BACKGROUND: Glycosmis is a genus of evergreen glabrous shrub and distributed all over India. It possesses various medicinal properties and is used in indigenous medicine for cough, rheumatism, anemia, and jaundice. Glycosmis arborea is a rich source of alkaloids, terpenoids, coumarins, as well as flavonoids. RESULTS: The chemical investigation of methanol fraction of the leaves of G. arborea led to the isolation of one new flavone C-glycoside along with three known flavanoids, named as 5,7-dihydroxy-2-[4-hydroxy-3-(methoxy methyl) phenyl]-6-C-β-d-glucopyranosyl flavone (4), 5,7,4(′)-trihydroxy-3(′)-methoxy flavone (1), 5,4(′)-dihydroxy-3(′)-methoxy-7-O-β-d-glucupyranosyl flavanone (2), and 5,4(′)-dihydroxy-3(′)-methoxy-7-O-(α-l-rhamnosyl-(1‴→6‴)-β-d-glucopyranosyl) flavanone (3), respectively. The structures of all compounds were elucidated with the help of nuclear magnetic resonance spectrometry. Pure compounds and fractions were evaluated for pest antifeedant and antimicrobial activity. CONCLUSION: Four compounds were isolated from the leaves of G. arborea. Among them, compound 4 showed significant antimicrobial activity