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1.
Nat Prod Res ; : 1-7, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39301610

RESUMEN

Phytochemical investigation of the n-butanol extracts of the herbaceous stems of Epheda intermedia led to the isolation of eight flavonoids that included three new flavonoid glycosides (1-3) and five previously reported analogues (4-8). Their structures have been identified on the basis of various spectral data. Besides, all the flavonoids were tested in vitro for their ability to inhibit α-glucosidase under the positive control of acarbose, and the results indicated that none of them exhibited significant inhibitory effect on α-glucosidase at 100 µM.

2.
Food Chem ; 460(Pt 3): 140541, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39137573

RESUMEN

Flavonoids have extensive biological qualities that support human health. A molecular networking strategy produced representative networks despite mass fragmentation of spectra of untargeted data-dependent acquisition approach to target flavonoid glycosides from Vicia bungei by using UHPLC-MS guided isolation. Using contemporary methods, seven chemicals were extracted and identified. Antioxidative and anti-inflammatory effects of these isolates were assessed in vitro on free radicals and inflammatory mediators, cytokines, enzymatic proteins. Two active compounds, apigenin 6-C-ß-D-galactopyranosyl-8-C-ß-D-xylopyranoside, and sphaerobioside, were further assessed for their binding affinity to target protein in in silico study. The molecular mechanism of sphaerobioside was found to involve suppression of LPS-stimulated inflammation by NF-κB inactivation by inhibiting nuclear translocation of p65 and prevention of phosphorylation of κB inhibitor α (IκBα) and IκB kinase (IKKα/ß). Furthermore, an analytical method was successfully established and employed to quantify the total extract using these seven chemicals present in this plant as markers.


Asunto(s)
Antiinflamatorios , Flavonoides , Frutas , Glicósidos , Fitoquímicos , Extractos Vegetales , Glicósidos/química , Glicósidos/farmacología , Frutas/química , Flavonoides/química , Flavonoides/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Fitoquímicos/química , Fitoquímicos/farmacología , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Humanos , FN-kappa B/metabolismo , Animales
3.
Fitoterapia ; 177: 106049, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38838827

RESUMEN

Three undescribed seco-iridoid glycosides, one undescribed flavonoid glycoside, and three known glycosides were isolated and identified from Gentiana olivieri Griseb. The structures of these compounds were determined through spectroscopic analysis and ECD calculations. Olivierisecosides NP (1-3) were identified as aromatic conjugated seco-iridoid glucosides, among them olivierisecoside N was representing a particularly rare subtype known as the morroniside seco-iridoids. The compounds 2, 3, 5, and 6 exhibited significant inhibition of COX-2 expression, particularly compound 5 which demonstrated the most pronounced inhibitory activity with IC50 value of 23.33 ± 0.51 µM. This study provides evidence for the potential development and utilization of G. olivieri as a source of anti-inflammatory components.


Asunto(s)
Antiinflamatorios , Flavonoides , Gentiana , Glicósidos , Glicósidos Iridoides , Fitoquímicos , Gentiana/química , Flavonoides/farmacología , Flavonoides/aislamiento & purificación , Flavonoides/química , Estructura Molecular , Antiinflamatorios/farmacología , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/química , Glicósidos/farmacología , Glicósidos/aislamiento & purificación , Glicósidos/química , Animales , Glicósidos Iridoides/farmacología , Glicósidos Iridoides/aislamiento & purificación , Glicósidos Iridoides/química , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Ratones , China , Células RAW 264.7
4.
Food Res Int ; 190: 114638, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38945627

RESUMEN

Tea trichomes were regarded as an essential evaluation index for reflecting tea flavor quality in terms of aroma and influence on infusion color. This study reveals the impact of golden oxidized trichomes on the color, volatile and non-volatile metabolites of black teas through comparative metabolomics combined quantitative analysis on hongbiluo (trichomes-deficiency black teas), hongjinluo (trichomes-rich black teas), and trichomes (from hongjinluo). Forty-six volatile components were detected using headspace solid-phase microextraction gas chromatography-mass spectrometry, while the results suggested that the contribution of trichomes to black teas is limited. A total of 60 marker non-volatile compounds were identified, including catechins, catechin oxidation products, flavonoid glycosides, organic acids, hydrolysable tannins and amino acids. Notably, p-coumaroyl-kaempferol glucosides, and catechin dimers demonstrated high levels in independent trichomes and showed a positive correlation with the brightness and yellow hue of black tea infusions, specifically kaempferol 3-O-di-(p-coumaroyl)-hexoside. Furthermore, results from fractional extraction analysis of separated trichomes provided that N-ethyl-2-pyrrolidinone-substituted epicatechin gallates, acylated kaempferol glycosides, and chromogenic catechins dimers, such as theaflavins, were primary color contributors in oxidized trichomes. Especially, we found that epicatechin gallate (ECG) and its derivates, 3'-O-methyl-ECG and N-ethyl-2-pyrrolidinone-substituted ECG, highly accumulated in trichomes, which may be associated with the varieties of hongbiluo and hongjinluo black teas. Eventually, addition tests were applied to verify the color contribution of trichome mixtures. Our findings employed comprehensive information revealing that golden oxidized trichomes contributed significantly to the brightness and yellow hue of black tea infusion, but their contribution to the aroma and metabolic profile is limited. These findings may contribute to the effective modulation of the infusion color during black tea production by regulating the proportion of tea trichomes or screening trichomes-rich or deficiency varieties.


Asunto(s)
Camellia sinensis , Color , Cromatografía de Gases y Espectrometría de Masas , Metabolómica , Oxidación-Reducción , , Tricomas , Compuestos Orgánicos Volátiles , Metabolómica/métodos , Té/química , Camellia sinensis/química , Compuestos Orgánicos Volátiles/análisis , Tricomas/química , Tricomas/metabolismo , Catequina/análisis , Catequina/análogos & derivados , Catequina/metabolismo , Microextracción en Fase Sólida , Hojas de la Planta/química , Metaboloma , Flavonoides/análisis
5.
Food Res Int ; 190: 114634, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38945623

RESUMEN

Drying is an important stage used to improve the quality of white tea (WT). However, the effect of the drying temperature on the key taste compounds in WT remains unclear. In this study, targeted metabolomics, molecular docking, and a simulated reaction were used to investigate the transformation mechanism of flavonoid glycosides (FGs) in WT during drying at 60, 80, and 100 °C and its impact on taste. There were 45 differential FGs in WT at three drying temperatures. Compared with the withering samples for 48 h, the total FGs contents at three drying temperatures showed a decreasing trend, with quercetin-3-O-galactoside and kaempferol-3-O-glucoside showing the most degradation. These results were confirmed via a simulated drying reaction of FGs standards. Drying at 80 and 100 °C contributed to the formation of flavonoid-C-glycosides, but only trace amounts of these compounds were observed. In addition, nine key taste FGs were selected using dose-over-threshold values. These FGs regulated the taste of WT, mainly by binding to taste receptors via hydrogen bond, hydrophobic and electrostatic interactions. Finally, the taste acceptability of WT dried at 60 °C was found to be the highest, as this method could properly reduce the contents of FGs, weaken the bitterness and astringency, and retain the sweet and umami taste. This study revealed for the first time the transformation mechanism of sensory-active FGs affected by drying temperature, which provides a novel perspective for the analysis of the formation mechanism of the unique flavor of WT and the optimization of this process.


Asunto(s)
Flavonoides , Glicósidos , Metabolómica , Simulación del Acoplamiento Molecular , , Flavonoides/química , Flavonoides/análisis , Glicósidos/química , Té/química , Metabolómica/métodos , Desecación/métodos , Gusto , Temperatura , Humanos , Manipulación de Alimentos/métodos , Camellia sinensis/química
6.
Chem Biodivers ; 21(7): e202400635, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38687253

RESUMEN

The phytochemical investigation of the fruits of Cornus officinalis yielded a new phenolic acid derivative, neophenolic acid A (1), and a novel flavonoid glycoside, (2R)-naringenin-7-O-ß-(6''-galloyl-glucopyranoside) (2 a), along with six known flavonoid glycosides (2 b-7). Their structures were determined by 1D, 2D NMR and HRESIMS data. The absolute configuration of 1 was established by ECD analysis. Compounds 1- 7 were evaluated for their neuroprotective activities against corticosterone (CORT)-induced injury in PC-12 cells. Compounds 1, 2 a, 2 b, 5, and 6 exhibited neuroprotective activities against CORT-induced neurotoxicity in PC-12 cells. The underlying mechanism study suggested that compounds 1, 2 a, 2 b, 5, and 6 were able to attenuate CORT-induced apoptosis and damage, increase the levels of MMP and decrease Ca2+ inward flow in PC-12 cells.


Asunto(s)
Apoptosis , Cornus , Frutas , Fármacos Neuroprotectores , Cornus/química , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/aislamiento & purificación , Animales , Frutas/química , Ratas , Células PC12 , Apoptosis/efectos de los fármacos , Corticosterona/farmacología , Supervivencia Celular/efectos de los fármacos , Estructura Molecular , Flavonoides/farmacología , Flavonoides/aislamiento & purificación , Flavonoides/química , Relación Estructura-Actividad , Calcio/metabolismo
7.
Heliyon ; 10(7): e28755, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38586372

RESUMEN

Fish mint, Houttuynia cordata Thunb. (HCT) is an edible vegetable that has also been used in traditional folk medicines. As both a medicinal herb and a dietary source, HCT has been clinically proven to be a pivotal ingredient in formulas administered to alleviate COVID-19 symptoms. With the increasing market demand for imported materials, ensuring the quality consistency of HCT becomes a significant concern. In this study, the growing time for hydroponically-cultivated HCT with seaweed extract and amino acids added (HCTW) reduced by half compared to conventional soil-cultivated HCT (HCTS). Key quantified components in HCTW, flavonoid glycosides and caffeoylquinic acid derivatives, exhibited a 143% increase over HCTS. These crucial constituents were responsible for possessing antioxidant activity (IC50 < 25 µg/mL) and anti-nitrite oxide production (IC50 < 20 µg/mL). An economically-designed hydroponic system with appropriate additives is proposed to replace HCTS with improvements of growth time, overall production yields, and bioactive qualities.

8.
Molecules ; 29(3)2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38338349

RESUMEN

Safflower (Carthamus tinctorius L.) has been recognized for its medicinal value, but there have been limited studies on the glycosyltransferases involved in the biosynthesis of flavonoid glycosides from safflower. In this research, we identified two highly efficient flavonoid O-glycosyltransferases, CtOGT1 and CtOGT2, from safflower performing local BLAST alignment. By constructing a prokaryotic expression vector, we conducted in vitro enzymatic reactions and discovered that these enzymes were capable of catalyzing two-step O-glycosylation using substrates such as kaempferol, quercetin, and eriodictyol. Moreover, they exhibited efficient catalytic activity towards various compounds, including flavones (apigenin, scutellarein), dihydrochalcone (phloretin), isoflavones (genistein, daidzein), flavanones (naringenin, glycyrrhizin), and flavanonols (dihydrokaempferol), leading to the formation of O-glycosides. The broad substrate specificity of these enzymes is noteworthy. This study provides valuable insights into the biosynthetic pathways of flavonoid glycosides in safflower. The discovery of CtOGT1 and CtOGT2 enhances our understanding of the enzymatic processes involved in synthesizing flavonoid glycosides in safflower, contributing to the overall comprehension of secondary metabolite biosynthesis in this plant species.


Asunto(s)
Carthamus tinctorius , Flavonas , Carthamus tinctorius/metabolismo , Glicosiltransferasas/metabolismo , Flavonoides/metabolismo , Glicósidos/metabolismo , Flavonas/metabolismo
9.
BMC Complement Med Ther ; 24(1): 69, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302935

RESUMEN

BACKGROUND: Litsea glutinosa (Lour.) C. B. Rob. belongs to the Litsea genus and is categorized under the family of Lauraceae. The study aimed to investigate the phytoconstituents and pharmacological properties of methanol extract of leaves of Litsea glutinosa, focusing on antidiabetic activity via in vivo and in silico techniques. METHODS: Extensive chromatographic and spectroscopic techniques were applied to isolate and characterize the constituents from the L. glutinosa plant species. The antidiabetic activity was studied in streptozotocin-induced diabetes mice, and the computational study of the isolated compounds was carried out by utilizing AutoDock Vina programs. In addition, the pharmacokinetic properties in terms of absorption, distribution, metabolism and excretion (ADME) and toxicological profiles of the isolated compounds were examined via in silico techniques. RESULTS: In the present study, two flavonoid glycosides 4΄-O-methyl (2 ̋,4 ̋-di-E-p-coumaroyl) afzelin (1) and quercetin 3-O-(2 ̋,4 ̋-di-E-p-coumaroyl)-α-L-rhamnopyranoside (2) were isolated from the leaves of L. glutinosa and characterized by 1H and 13C NMR, COSY, HSQC, HMBC, and mass spectral data. Although compounds 1 and 2 have been reported twice from Machilis litseifolia and Lindera akoensis, and Machilis litseifolia and Mammea longifolia, respectively, this is the first report of this isolation from a Litsea species. Administering the methanolic extract of L. glutinosa at doses of 300 and 500 mg/kg/day to mice with diabetes induced by streptozotocin led to a significant decrease in fasting blood glucose levels (p < 0.05) starting from the 7th day of treatment. Besides, the computational study and PASS analysis endorsed the current in vivo findings that the both isolated compounds exerted higher binding affinities to human pancreatic α-amylase and aldose reductase than the conventional drugs. The in silico ADMET analysis revealed that the both isolated compounds have a favorable pharmacokinetic and safety profile suitable for human consumption. CONCLUSION: According to the current outcomes obtained from in vivo and in silico techniques, the leaf extract of L. glutinosa could be a natural remedy for treating diabetes, and the isolated phytoconstituents could be applied against various illnesses, mainly hyperglycemia. However, more investigations are required for extensive phytochemical isolation and pharmacological activities of these phytoconstituents against broader targets with exact mechanisms of action.


Asunto(s)
Diabetes Mellitus , Litsea , Humanos , Animales , Ratones , Flavonoides/química , Glicósidos/farmacología , Litsea/química , Hipoglucemiantes/farmacología , Estreptozocina
10.
Food Res Int ; 178: 113934, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38309905

RESUMEN

Bee pollen is hailed as a treasure trove of human nutrition and has progressively emerged as the source of functional food and medicine. This review conducts a compilation of nutrients and phytochemicals in bee pollen, with particular emphasis on some ubiquitous and unique phenolamides and flavonoid glycosides. Additionally, it provides a concise overview of the diverse health benefits and therapeutic properties of bee pollen, particularly anti-prostatitis and anti-tyrosinase effects. Furthermore, based on the distinctive structural characteristics of pollen walls, a substantial debate has persisted in the past concerning the necessity of wall-disruption. This review provides a comprehensive survey on the necessity of wall-disruption, the impact of wall-disruption on the release and digestion of nutrients, and wall-disruption techniques in industrial production. Wall-disruption appears effective in releasing and digesting nutrients and exploiting bee pollen's bioactivities. Finally, the review underscores the need for future studies to elucidate the mechanisms of beneficial effects. This paper will likely help us gain better insight into bee pollen to develop further functional foods, personalized nutraceuticals, cosmetics products, and medicine.


Asunto(s)
Nutrientes , Polen , Abejas , Humanos , Animales , Polen/química , Flavonoides/análisis , Glicósidos/análisis , Fitoquímicos/análisis
11.
Fitoterapia ; 175: 105863, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38373500

RESUMEN

Thirty four compounds were identified in Sorbus torminalis (L.) fruit extracts of different maturity types by means of LC-DAD-MS (ESI+) fragmentation analysis. Both immature and mature fruits were rich in flavonoid glycosides esterified with hydroxycinnamic, phenolic and dicarboxylic acids along with benzoic, phenylpropanoic and cinnamoyl quinic acid derivatives with many of them being detected for the first time in Sorbus species and in literature. Extracts and fractions were tested for their antioxidant activity (DPPH, chemiluminescence, Rancimat assays) and the estimation of the phenolic content was carried out through Folin-Ciocalteu reagent. Ethyl acetate fraction exhibited the highest scavenging activity determined as EC50 = 1.58 ± 0.22 µg/mL and EC50 = 1.64 ± 0.24 µg/mL for immature and mature fruits respectively with the DPPH test. Chemiluminescence test indicated the same fraction having the strongest antioxidant activity with an IC50 0.41 ± 0.06 µg/mL and IC50 0.50 ± 0.02 µg/mL in both maturity types. The ethyl acetate fraction of the mature fruits is considered the most potent Aldose Reductase 2 (ALR2) inhibitor with 79% demonstrating the high nutritional value of Sorbus torminalis (L.) mature fruits as a defense mechanism against the onset of diabetes mellitus secondary complications leading to the utilization of the plant for nutritional and pharmaceutical purposes.


Asunto(s)
Antioxidantes , Frutas , Fitoquímicos , Extractos Vegetales , Sorbus , Frutas/química , Sorbus/química , Antioxidantes/farmacología , Antioxidantes/aislamiento & purificación , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Extractos Vegetales/farmacología , Extractos Vegetales/química , Estructura Molecular , Fenoles/farmacología , Fenoles/aislamiento & purificación , Fenoles/análisis , Flavonoides/farmacología , Flavonoides/aislamiento & purificación
12.
Planta ; 259(2): 50, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38285114

RESUMEN

MAIN CONCLUSION: The oxidosqualene cyclases (OSCs) generating triterpenoid skeletons in Cyclocarya paliurus were identified for the first time, and two uridine diphosphate (UDP)-glycosyltransferases (UGTs) catalyzing the glycosylation of flavonoids were characterized. Cyclocarya paliurus, a native rare dicotyledonous plant in China, contains an abundance of triterpenoid saponins and flavonoid glycosides that exhibit valuable pharmaceutical effects in preventing hypertension, hyperlipidemia, and diabetes. However, the molecular mechanism explaining the biosynthesis of triterpenoid saponin and flavonoid glycoside in C. paliurus remains unclear. In this study, the triterpene content in different tissues and the expression pattern of genes encoding the key enzymes associated with triterpenoid saponin and flavonoid glycoside biosynthesis were studied using transcriptome and metabolome analysis. The eight upstream oxidosqualene cyclases (OSCs) involved in triterpenoid saponin biosynthesis were functionally characterized, among them CpalOSC6 catalyzed 2,3;22,23-dioxidosqualene to form 3-epicabraleadiol; CpalOSC8 cyclized 2,3-oxidosqualene to generate dammarenediol-II; CpalOSC2 and CpalOSC3 produced ß-amyrin and CpalOSC4 produced cycloartenol, while CpalOSC2-CpalOSC5, CpalOSC7, and CpalOSC8 all produced lanosterol. However, no catalytic product was detected for CpalOSC1. Moreover, two downstream flavonoid uridine diphosphate (UDP)-glycosyltransferases (UGTs) (CpalUGT015 and CpalUGT100) that catalyze the last step of flavonoid glycoside biosynthesis were functionally elucidated. These results uncovered the key genes involved in the biosynthesis of triterpenoid saponins and flavonoid glycosides in C. paliurus that could be applied to produce flavonoid glycosides and key triterpenoid saponins in the future via a synthetic strategy.


Asunto(s)
Saponinas , Escualeno/análogos & derivados , Triterpenos , Glicósidos , Flavonoides , Saponinas/genética , Glicosiltransferasas , Uridina Difosfato
13.
Fitoterapia ; 173: 105820, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38211642

RESUMEN

In this study, we specifically focused on the crude methanolic leaf extract of Byrsonima coccolobifolia, investigating its antifungal potential against human pathogenic fungi and its antiviral activity against COVID-19. Through the use of high-performance liquid chromatography coupled with electrospray ionization ion trap tandem mass spectrometry, direct infusion electrospray ionization ion trap tandem mass spectrometry, and chromatographic dereplication procedures, we identified galloyl quinic acid derivatives, catechin derivatives, proanthocyanidins, and flavonoid glycosides. The broth dilution assay revealed that the methanolic leaf extract of B. coccolobifolia exhibits antifungal activity against Cryptococcus neoformans (IC50 = 4 µg/mL). Additionally, docking studies were conducted to elucidate the interactions between the identified compounds and the central residues at the binding site of biological targets associated with COVID-19. Furthermore, the extract demonstrated an in vitro half-maximum effective concentration (EC50 = 7 µg/mL) and exhibited significant selectivity (>90%) toward SARS-CoV-2.


Asunto(s)
COVID-19 , Extractos Vegetales , Humanos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Antifúngicos , Estructura Molecular , SARS-CoV-2 , Espectrometría de Masa por Ionización de Electrospray/métodos , Metanol , Antivirales/farmacología , Cromatografía Líquida de Alta Presión/métodos
14.
Food Res Int ; 176: 113798, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38163709

RESUMEN

Camellia oleifera cake is a by-product, which is rich in functional chemical components. However, it is typically used as animal feed with no commercial value. The purpose of this study was to isolate and identify compounds from Camellia oleifera cake using a combination of foam fractionation and high-speed countercurrent chromatography (HSCCC) and to investigate their biological activities. Foam fractionation with enhanced drainage through a hollow regular decahedron (HRD) was first established for simultaneously enriching flavonoid glycosides and saponins for further separation of target compounds. Under suitable operating conditions, the introduction of HRD resulted in a threefold increase in enrichment ratio with no negative effect on recovery. A novel elution-extrusion countercurrent chromatography (EECCC) coupled with the consecutive injection mode was established for the successful simultaneous isolation of flavonoid glycosides and saponins. As a result, 38.7 mg of kaemferol-3-O-[2-O-D-glucopyranosyl-6-O-α-L-rhamnopyranosyl]-ß-D-glucopyranoside (purity of 98.17%, FI), 70.8 mg of kaemferol-3-O-[2-O-ß-D-xylopyranosyl-6-O-α-L-rhamnopyranosyl]-ß-D-glucopyranoside (purity of 97.52%, FII), and 560 mg of an oleanane-type saponin (purity of 92.32%, FIII) were separated from the sample (900 mg). The present study clearly showed that FI and II were natural antioxidants (IC50 < 35 µg/mL) without hemolytic effect. FIII displayed the effect of inhibiting Hela cell proliferation (IC50 < 30 µg/mL). Further erythrocyte experiments showed that this correlated with the extremely strong hemolytic effect of FIII. Overall, this study offers a potential strategy for efficient and green isolation of natural products, and is beneficial to further expanding the application of by-products (Camellia oleifera cake) in food, cosmetics, and pharmacy.


Asunto(s)
Camellia , Citostáticos , Saponinas , Humanos , Animales , Distribución en Contracorriente/métodos , Antioxidantes/farmacología , Citostáticos/análisis , Camellia/química , Células HeLa , Glicósidos/química , Saponinas/análisis , Flavonoides/análisis
15.
Food Chem ; 439: 138133, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38064841

RESUMEN

This study was the first to comprehensively investigate the metabolic mechanism of flavonoid glycosides (FGs) and their contribution to flavor evolution during white tea processing using quantitative descriptive analysis, metabolomics, dose-over-threshold factors and pseudo-first-order kinetics. A total of 223 flavonoids were identified. Total FGs decreased from 7.02 mg/g to 4.35 mg/g during processing, compared to fresh leaves. A total of 86 FGs had a significant impact on the flavor evolution and 9 key flavor FGs were identified. The FG biosynthesis pathway was inhibited during withering, while the degradation pathway was enhanced. This promoted the degradation of 9 key flavor FGs following pseudo-first-order kinetics during withering. The degradation of the FGs contributed to increase the taste acceptance of white tea from -4.18 to 1.32. These results demonstrated that water loss stress during withering induces the degradation of key flavor FGs, contributing to the formation of the unique flavor of white tea.


Asunto(s)
Camellia sinensis , Flavonoides , Flavonoides/análisis , Glicósidos/metabolismo , Camellia sinensis/metabolismo , Metabolómica/métodos , Té/metabolismo
16.
Molecules ; 28(23)2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38067527

RESUMEN

Fenugreek (Trigonella foenum-graecum) has a great beneficial health effect; it has been used in traditional medicine by many cultures. Likewise, the α-amylase inhibitors are potential compounds in the development of drugs for the treatment of diabetes. The beneficial health effects of fenugreek lead us to explore the chemical composition of the seeds and their antioxidant and α-amylase inhibition activities. The flavonoid extraction from fenugreek seeds was achieved with methanol through a Soxhlet apparatus. Then, the flavonoid glycosides were characterized using HPLC-DAD-ESI-MS analysis. The antioxidant capacity of fenugreek seed was measured using DPPH, FRAP, ABTS, and CUPRAC assays. Finally, the α-amylase inhibition activity was carried out using in vitro and in silico methods. The methanolic extract was found to contain high amounts of total phenolics (154.68 ± 1.50 µg GAE/mg E), flavonoids (37.69 ± 0.73 µg QE/mg E). The highest radical-scavenging ability was recorded for the methanolic extract against DPPH (IC50 = 556.6 ± 9.87 µg/mL), ABTS (IC50 = 593.62 ± 9.35 µg/mL). The ME had the best reducing power according to the CUPRAC (A 0.5 = 451.90 ± 9.07 µg/mL). The results indicate that the methanolic extracts of fenugreek seed best α-amylase inhibition activities IC50 = 653.52 ± 3.24 µg/mL. Twenty-seven flavonoids were detected, and all studied flavonoids selected have good affinity and stabilize very well in the pocket of α-amylase. The interactions between the studied flavonoids with α-amylase were investigated. The flavonoids from fenugreek seed present a good inhibitory effect against α-amylase, which is beneficial for the prevention of diabetes and its complications.


Asunto(s)
Diabetes Mellitus , Trigonella , Humanos , Antioxidantes/química , Trigonella/química , Flavonoides/farmacología , Flavonoides/análisis , Simulación del Acoplamiento Molecular , alfa-Amilasas , Cromatografía Líquida de Alta Presión , Extractos Vegetales/química , Metanol/química , Semillas/química
17.
Foods ; 12(18)2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37761124

RESUMEN

In this study, 12 flavonoid glycosides were selected based on virtual screening and the literature, and Quercimeritrin was selected as the best selective inhibitor of α-glucosidase through in vitro enzyme activity inhibition experiments. Its IC50 value for α-glucosidase was 79.88 µM, and its IC50 value for α-amylase >250 µM. As such, it could be used as a new selective inhibitor of α-glucosidase. The selective inhibition mechanism of Quercimeritrin on the two starch-digesting enzymes was further explored, and it was confirmed that Quercimeritrin had a strong binding affinity for α-glucosidase and occupied the binding pocket of α-glucosidase through non-covalent binding. Subsequently, animal experiments demonstrated that Quercimeritrin can effectively control postprandial blood glucose in vivo, with the same inhibitory effect as acarbose but without side effects. Our results, therefore, provide insights into how flavone aglycones can be used to effectively control the rate of digestion to improve postprandial blood glucose levels.

18.
ACS Synth Biol ; 12(9): 2740-2749, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37566738

RESUMEN

Flavonoids are an essential class of secondary metabolites found in plants and possess various nutritional, medicinal, and agricultural properties. However, the poor water solubility of flavonoid aglycones limits their potential applications. To overcome this issue, glycosylation is a promising approach for improving water solubility and bioavailability. In this study, we constructed a flavonoid-7-O-disaccharide biosynthetic pathway with flavonoid aglycones as substrates in Saccharomyces cerevisiae. Subsequently, through metabolic engineering and promoter strategies, we constructed a UDP-rhamnose regeneration system and optimized the UDP-glucose (UDPG) synthetic pathway. The optimized strain produced up to 131.3 mg/L eriocitrin. After this, the chassis cells were applied to other flavonoids, with substrates such as (2S)-naringenin, (2S)-hesperetin, diosmetin, and (2S)-eriodictyol, which resulted in the synthesis of 179.9 mg/L naringin, 276.6 mg/L hesperidin, 249.0 mg/L neohesperidin, 30.4 mg/L diosmin, and 100.7 mg/L neoeriocitrin. To the best of our knowledge, this is the first report on the biosynthesis of flavonoid-7-O-disaccharide.


Asunto(s)
Flavonoides , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Flavonoides/metabolismo , Glicosilación , Disacáridos/metabolismo , Agua , Ingeniería Metabólica
19.
Plant Cell Physiol ; 64(12): 1523-1533, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-37572104

RESUMEN

Exposure to UV-B radiation, an intrinsic component of solar light, is detrimental to all living organisms as chromophore units of DNA, RNA and proteins readily absorb high-energy photons. Indirect damage to the same molecules and lipids is mediated by elevated reactive oxygen species (ROS) levels, a side effect of exposure to UV-B stress. To protect themselves from UV-B radiation, plants produce phytochemical sunscreens, among which flavonoids have shown to be particularly effective. The core aglycone of flavonoid molecules is subjected to chemical decoration, such as glycosylation and acylation, further improving sunscreen properties. In particular, acylation, which adds a phenolic ring to flavonoid molecules, enhances the spectral absorption of UV-A and UV-B rays, providing to this class of compounds exceptional shielding power. In this study, we comprehensively analyzed the responses to UV-B radiation in four Brassicaceae species, including Arabidopsis thaliana, Brassica napus, Brassica oleracea, and Brassica rapa. Our study revealed a complete reprogramming of the central metabolic pathway in response to UV-B radiation characterized by increased production of functional precursors of specialized metabolites with UV-B shielding properties, indicating a targeted effort of plant metabolism to provide increased protection. The analysis of specialized metabolites and transcripts revealed the activation of the phenylpropanoid-acetate pathway, leading to the production of specific classes of flavonoids and a cross-species increase in phenylacylated-flavonoid glucosides with synapoyl glycoside decorations. Interestingly, our analysis also revealed that acyltransferase genes of the class of serine carboxypeptidase-like (SCPLs) proteins are costitutively expressed, but downregulated in response to UV-B radiation, possibly independently of the ELONGATED HYPOCOTYL 5 (HY5) signaling pathway.


Asunto(s)
Arabidopsis , Brassicaceae , Brassicaceae/metabolismo , Flavonoides/metabolismo , Arabidopsis/genética , Rayos Ultravioleta , Glicósidos/metabolismo , Plantas/metabolismo
20.
Antioxidants (Basel) ; 12(7)2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37508005

RESUMEN

Berberis vulgaris L. is currently widely studied for its antioxidant and chemopreventive properties, especially with regard to the beneficial properties of its fruits. Although the bark and roots have been well known and used in traditional medicine since ancient times, little is known about the other parts of this plant. The aim of the research was to determine the antioxidant and LOX inhibitory activity effects of extracts obtained from the leaves, fruits, and stems. Another aim of the work was to carry out the quantitative and qualitative analysis of phenolic acids, flavonoid aglycones, and flavonoid glycosides. The extracts were obtained with the use of ASE (accelerated solvent extraction). The total content of polyphenols was determined and was found to vary depending on the organ, with the highest amount of polyphenols found in the leaf extracts. The free radical scavenging activity of the extracts was determined spectrophotometrically in relation to the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical, with results ranging from 63.9 mgTE/g for the leaves to 65.2 mgTE/g for the stem. Antioxidant activity was also assessed using the ABTS test. The lowest value was recorded for the barberry fruit (117.9 mg TE/g), and the highest level was found for the barberry leaves (140.5 mgTE/g). The oxygen radical absorbance capacity test (ORAC) showed the lowest value for the stem (167.7 mgTE/g) and the highest level for the leaves (267.8 mgTE/g). The range of the percentage inhibition of LOX was determined as well. The percentage inhibition of the enzyme was positively correlated with the sum of the flavonoids, TPC, TFC, and the content of selected flavonoids. Phenolic acids, flavonoid aglycones, and flavonoid glycosides were determined qualitatively and quantitatively in individual parts of Berberis vulgaris L. The content of phenolic acids, flavonoid aglycones, and flavonoid glycosides was determined with the LC-MS/MS method. The following phenolic acids were quantitatively and qualitatively identified in individual parts of Berberis vulgaris L.: gallic acid, 3-caffeoylquinic acid, protocatechuic acid, 5-caffeoylquinic acid, 4-caffeoylquinic acid, and caffeic acid. The flavonoid glycosides determined were: eleutheroside E, Eriodictyol-7-glucopyranoside, rutin, hyperoside, isoquercitin, luteoloside, narcissoside, naringenin-7-glucoside, isorhamnetin-3-glucoside, afzeline, and quercitrin. Flavonoid aglycones such as catechin, luteolin, quercetin, and eriodictyol were also determined qualitatively and quantitatively.

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