Main Flavonoids Research Articles

A Study of Polyphenolic Compounds and in vitro Antioxidant Activity of Trianthema portulacastrum Linn. Extracts

Background: Trianthema portulacastrum Linn. is an exotic plant growing as weed in Africa, Southeast Asia and tropical America. Chemical fingerprinting under the present study was undertaken to characterize the polyphenolic compounds and antioxidant activities present in the plant. Methods: Several in vitro antioxidant assays were performed to evaluate the antioxidant activities in aqueous, alcoholic and hydro-alcoholic extracts. Characterization of polyphenolic compounds was done by HPLC and GCMS analyses. Result: Total phenols, flavonoids and total antioxidant activity as assessed by DPPH, ABTS and total antioxidant capacity assays was found to be maximum in hydroethanolic extract of the plant. HPLC analysis confirmed the presence of gallic acid, protocatechuic acid, catechin hydrate, vanillic acid, epicatechin, p-coumaric acid, rutin, salicylic acid, myricetin, quercetin and trans-cinnamic acid in plant extracts being maximum in hydroethanolic followed by aqueous, hydromethanolic, ethanolic and then methanolic extracts. Catechin, epicatechin, rutin, myricetin and quercetin were main flavonoid compounds in most of the plant extracts. GCMS analysis also confirmed the presence of several other antioxidants. Based on the findings of the phytochemical analyses and in vitro antioxidative studies, it can be clearly established that Trianthema portulacastrum has rich amounts of potent polyphenolic and flavonoid compounds having antioxidant properties.

Phytochemicals and Biological Activities of Pulicaria genus: Emphasis on the Flavonoids and Sesquiterpenoids and Cytotoxicity Effects

Abstract: The use of herbal remedies is more current in illnesses with chronic diseases. One of these important applications is the usage of many plant-derived compounds as cytotoxic agents for the treatment of cancers. Various research has been done on several species of Pulicaria genus for the evaluation of antihistaminic, antimicrobial, antitumor, antiinflammatory, antioxidant, antibacterial, antifungal, insecticide, and leishmanicidal activities. Some studies have shown that these plants have a rich pool of biometabolites like diterpenes, sesquiterpenes, caryophyllenes, flavonoids, and sesquiterpenoids. The main components in several species of this genus are flavonoids and sesquiterpenoids, which have been identified in chemotaxonomic studies and have shown cytotoxic properties. The Scopus and Science Direct sites were studied to find articles on flavonoid and sesquiterpenoid compounds that have been isolated from the Pulicaria genus. : Several biological compounds were isolated from different species of the Pulicaria genus. The main compounds are flavonoids and sesquiterpenoids, which have different biological effects. Its main effect is cytotoxic effect against several cancer cell lines. This study indicates that the Pulicaria genus has cytotoxic activity but posterity studies are needed to probe the active compounds and their possible expansion as novel anticancer drugs.

Influence of Cultivar and Turbidity on Physicochemical Properties, Functional Characteristics and Volatile Flavor Substances of Pomelo Juices

In this study, the influences of pomelo cultivars on physicochemical properties, functional characteristics, and volatile compounds of juices were investigated. Among these six varieties, the highest juice yield (73.22%) was obtained in grapefruit. Sucrose and citric acid were the main sugar component and organic acid of pomelo juices, respectively. The results showed that the cv. Pingshanyu pomelo juice and grapefruit juice had the highest sucrose (87.14 g L-1, 97.69 g L-1) and citric acid content (14.49 g L-1, 13.7 g L-1), respectively. Moreover, the naringenin was the main flavonoid of pomelo juice. Additionally, the total phenolics, total flavonoids, and ascorbic acid concentrations of grapefruit and cv. Wendanyu pomelo juice were higher than those of other varieties of pomelo juices. Furthermore, 79 volatile substances were identified from the juices of six pomelo cultivars. Hydrocarbons were the predominant volatile substances, and the limonene was the characteristic hydrocarbon substance of pomelo juice. In addition, the pulp content of pomelo juice also presented great effects on its quality and volatile compounds composition. Compared to low pulp juice, the corresponding high pulp juice had higher sucrose, pH, total soluble solid, acetic acid, viscosity, bioactive substances and volatile substances. The effects of cultivars and variation in turbidity on juice are highlighted. It is useful for pomelo breeders, packers and processors to understand the quality of the pomelo they are working with. This work could provide valuable information on selecting suitable pomelo cultivars for juice processing.

Optimization of supercritical fluid extraction of polar flavonoids from Robinia pseudoacacia L. heartwood

The black locust, known as an invasive species, represent many advantages, mainly due to its rapid growth rate and its richness with interesting flavonoids. In this study, supercritical fluid extraction of the two main flavonoids dihydrorobinetin and robinetin, was optimized using a three level Box-Behnken response surface design. The conditions investigated to influence the extraction yield of these flavonoids were temperature (40–80 °C), pressure (10–20 MPa) and modifier’s percentage EtOH:H2O 80:20 (10 %−30 %). The response was quantified using an UHPLC-DAD optimized chromatographic method. The results showed the influence of the extraction conditions on the yield of the molecules of interest. The data were fitted into a second-order polynomial equation, the multiple regression analysis showed a high determination coefficient value (R2) of 0.93. The optimal extraction conditions were 10 MPa, 80 °C and extraction phase composition of CO2:EtOH:H2O 80:16:4 for 30 min. These conditions allowed for the recovery 49.2 mg of flavonoids for 1 g of dried wood powder.

Effect of Skin Melinjo Extract (Gnetum Gnemon) On Expression URAT1 and GLUT9 Genes In Hyperuricemia

Hyperuricemia is defined as a metabolic syndrome disease with markers characteristic of uric acid production that exceed normal limits. Normal uric acid levels range from 3.4-7.0 mg/dl in adult men and 2.4 -6.0 mg/dl in adult women. So if uric acid levels exceed the normal limit, it will cause uric acid can not be fully metabolized and cause hyperuricemia. About 70% of uric acid is excreted through the kidneys. The kidneys are therefore organs that have an important role in maintaining uric acid levels and uric acid homeostasis in general, through complex molecular mechanisms. Reabsorption of uric acid that occurs in the kidneys by URAT1 and GLUT9 has an important role in uric acid levels in the human body, where uric acid is reabsorbed by the kidneys will then be flowed back into the blood so that it affects the levels of uric acid in the human body. Preliminary data showed that ethanol extract of melinjo skin contains 3 main Flavonoid compounds that have a higher Binding affinity value compared to allopurinol, so it has a higher effect in overcoming uric acid levels.

Antidiabetic Potential and Chronic Toxicity of Hydroalcoholic Extract of Echeveria subrigida Leaves

Pharmacognosy Research,2023,15,2,315-327.DOI:10.5530/pres.15.2.034Published:February 2023Type:Original Article Authors:Belinda Heredia-Mercado, Francisco Delgado-Vargas, Lorenzo Ulises Osuna-Martínez, Elvic Noguera-Corona, José Ángel López-Valenzuela, Rosalio Ramos-Payán, and Gabriela López-Angulo Author(s) affiliations:Belinda Heredia-Mercado1,#, Francisco Delgado-Vargas1, 2,#, Lorenzo Ulises Osuna-Martínez2, Elvic Noguera-Corona3, José Ángel López-Valenzuela1, Rosalio Ramos-Payán2, Gabriela López-Angulo1,* 1Food Science and Technology Program, Autonomous University of Sinaloa, Culiacan, Sinaloa, MEXICO. 2Biomedical Sciences Program of the School of Chemical and Biological Sciences, Autonomous University of Sinaloa, Culiacan, Sinaloa, MEXICO. 3School of Medicine, Autonomous University of Sinaloa, Culiacan, Sinaloa, MEXICO. #Authors with equal contribution. Abstract:Background: Echeveria subrigida extracts have biological activities of human health importance. However, the in vivo effects on glucose levels and chronic toxicity are unknown. Objectives: To analyse the in vivo hypoglycemic and antihyperglycemic effects (50, 100, and 200 mg/kg b.w.) and chronic toxicity (1000 mg/kg b.w. for 270 days) of the hydroalcoholic extract of E. subrigida (HE–Es) in BALB/c mice. Materials and Methods: The HE–Es was analysed by HPLC. Glucose levels were measured to establish the effects on glycemia. Different parameters were registered in the toxicity assay: e.g., feed consumption, appearance/behaviour, biochemical and haematological parameters and liver and kidney histologies. Results: Quercetin–3-O-β-glucoside and isorhamnetin–3-O-β-glucoside were the main flavonoids in the HE–Es. Glycemia was reduced by the HE–Es (200 mg/kg b.w., 49.1%) and glibenclamide (10 mg/kg b.w., 52%) treatments. Comparing the antihyperglycemic activities, similar reductions were found between HE–Es (100 mg/kg b.w., 29.32%; 200 mg/kg, 28.99%) and acarbose (10 mg/kg b.w., 19.87%) treatments. On the other hand, the HE–Es was innocuous in mice (LD50 > 1000 mg/kg b.w.), and the results suggested that HE–Es had adaptogenic, and immunostimulant activities. The hepatic and renal histologies were normal; however, male mice showed level zero steatosis that disappeared in the HE–Es satellite after treatment withdrawal. Conclusion: This study reports for the first time the in vivo effects on blood glucose levels of HE–Es and chronic toxicity of a Crassulaceae plant, supporting the antidiabetic potential and safety of HE–Es. Future studies must corroborate the effects of HE–Es in humans, allowing its use in high-value formulations. Keywords:Antihyperglycemia, Crassulaceae family, Hypoglycemia, Plant natural extract, SafetyView:PDF (677.27 KB)

A Comprehensive Analysis to Elucidate the Effects of Spraying Mineral Elements on the Accumulation of Flavonoids in Epimedium sagittatum during the Harvesting Period.

The harvesting period is a critical period for the accumulation of flavonoids in the leaves of the important medicinal plant Epimedium sagittatum. In this study, we conducted an experiment on E. sagittatum leaves sprayed with mineral elements with the aim of improving the quality of the herbal leafage during the harvesting period. We elucidated the changes in flavonoids (icariin, epimedin A, epimedin B, and epimedin C) in E. sagittatum leaves. The sum of main flavonoids content reached a maximum (11.74%) at 20 days after the high-concentration Fe2+ (2500 mg·L-1) treatment. We analyzed the FT-IR spectra characteristics of E. sagittatum leaf samples using the FT-IR technique, and constructed an OPLS-DA model and identified characteristic peaks to achieve differentiated identification of E. sagittatum. Further, widely untargeted metabolomic analysis identified different classes of metabolites. As the most important characteristic flavonoids, the relative contents of icariin, icaritin, icariside I, and icariside II were found to be up-regulated by high-Fe2+ treatment. Our experimental results demonstrate that high-concentration Fe2+ treatment is an effective measure to increase the flavonoids content in E. sagittatum leaves during the harvesting period, which can provide a scientific basis for the improvement of E. sagittatum leaf cultivation agronomic measures.

Comparative Study of the Flavonoid Content in Radix Scutellaria from Different Cultivation Areas in China.

Scutellariabaicalensis Georgi, an important perennial herb, is widely distributed and used all over the world. The root of S. baicalensis (Radix Scutellaria) is rich in flavonoids with a variety of bioactive effects and is widely used in clinic. The different geographical and climatic conditions of different cultivated areas of S. baicalensis lead to the differences of the main components in Radix Scutellaria. The main objective of this study was to evaluate the difference of flavonoid content in Radix Scutellaria from different cultivated areas in China. The mobile phase system, elution gradient, detection wavelength, and other chromatographic conditions for high-performance liquid chromatography-diode array detection (HPLC-DAD) determination of 8 flavonoids in Radix Scutellaria were optimized. The contents of flavonoids in 38 samples of Radix Scutellaria collected from seven main genuine cultivated areas were determined, and the correlation between the content, cultivated area, and the biological activities of Radix Scutellaria was compared. The results implied that baicalin, wogonoside, and baicalein were the three main flavonoids with the highest contents in Radix Scutellaria. The content of flavonoids in different cultivated areas was very different, which had significant regionality and was closely related to the natural conditions of various places. The antioxidant and antitumor activities of the extract of Radix Scutellaria were closely related to the content of flavonoids, and high contents of baicalin, wogonoside, and baicalein positively improved biological activities.

Honey and Alzheimer's Disease-Current Understanding and Future Prospects.

Alzheimer's disease (AD), a leading cause of dementia, has been a global concern. AD is associated with the involvement of the central nervous system that causes the characteristic impaired memory, cognitive deficits, and behavioral abnormalities. These abnormalities caused by AD is known to be attributed by extracellular aggregates of amyloid beta plaques and intracellular neurofibrillary tangles. Additionally, genetic factors such as abnormality in the expression of APOE, APP, BACE1, PSEN-1, and PSEN-2 play a role in the disease. As the current treatment aims to treat the symptoms and to slow the disease progression, there has been a continuous search for new nutraceutical agent or medicine to help prevent and cure AD pathology. In this quest, honey has emerged as a powerful nootropic agent. Numerous studies have demonstrated that the high flavonoids and phenolic acids content in honey exerts its antioxidant, anti-inflammatory, and neuroprotective properties. This review summarizes the effect of main flavonoid compounds found in honey on the physiological functioning of the central nervous system, and the effect of honey intake on memory and cognition in various animal model. This review provides a new insight on the potential of honey to prevent AD pathology, as well as to ameliorate the damage in the developed AD.

Effect of Glomus mosseae, cadmium, and elevated air temperature on main flavonoids and phenolic acids contents in alfalfa.

Global warming and heavy metal-contaminated soils co-occur in natural ecosystems. Flavonoids and phenolic acids in plants have significant antioxidant activity and free radical scavenging ability, which can quickly increase under adverse environments. Arbuscular mycorrhizal fungi (AMF) colonization can affect the synthesis of flavonoids and phenolic acids in host plants. This study focused on the main effect of Glomus mosseae, cadmium (Cd, 8mgkg-1 dry soils), and elevated temperature (ET, + 3°C) on main flavonoids and phenolic acids in 120-d Medicago sativa L. (alfalfa). Elevated temperature decreased G. mosseae colonization ratio by 49.5% under Cd exposure. Except for p-hydroxybenzoic acid, flavonoids and phenolic acids content in shoots increased (p < 0.05) under G. mosseae + Cd relative to Cd only. G. mosseae and Cd showed significant effects on rutin, quercetin, apigenin, liquiritigenin, gallic acid, p-hydroxybenzoic acid, p-coumaric acid, and ferulic acid, and G. mosseae colonization led to increases in these compounds by 41.7%, 35.4%, 32.2%, 267.8%, 84.7%, 33.5%, 102.8%, and 89.4%, respectively, under ET + Cd. Carbon, N, and Cd in alfalfa and G. mosseae colonization rate were significant factors on flavonoids and phenolic acids accumulation. Additionally, P content in shoots significantly influenced flavonoids content. G. mosseae inoculation significantly stimulated the synthesis of main flavonoids and phenolic acids in alfalfa shoots under ET + Cd, which was helpful to understand the regulation of AMF on non-enzyme antioxidant system of plants grown in heavy metal-contaminated soils under global change scenarios.

Dihydromyricetin Attenuates Diabetic Cardiomyopathy by Inhibiting Oxidative Stress, Inflammation and Necroptosis via Sirtuin 3 Activation.

Dihydromyricetin (DHY), the main flavonoid component in Ampelopsis grossedentata, has important benefits for health. The present study aimed to investigate the exact effects and possible mechanisms of DHY on diabetic cardiomyopathy (DCM). Male C57BL/6 mice and sirtuin 3 (SIRT3) knockout (SIRT3-KO) mice were injected with streptozotocin (STZ) to induce a diabetic model. Two weeks later, DHY (250 mg/kg) or carboxymethylcellulose (CMC) were administrated once daily by gavage for twelve weeks. We found that DHY alleviated fasting blood glucose (FBG) and triglyceride (TG) as well as glycosylated hemoglobin (HbA1c) levels; increased fasting insulin (FINS); improved cardiac dysfunction; ameliorated myocardial hypertrophy, fibrosis and injury; suppressed oxidative stress, inflammasome and necroptosis; but improved SIRT3 expression in STZ-induced mice. Neonatal rat cardiomyocytes were pre-treated with DHY (80 μM) with or without high glucose (HG) stimulation. The results showed that DHY attenuated cell damage but improved SIRT3 expression and inhibited oxidative stress, inflammasome and necroptosis in cardiomyocytes with high glucose stimulation. Moreover, the above protective effects of DHY on DCM were unavailable in SIRT3-KO mice, implying a promising medical potential of DHY for DCM treatment. In sum, DHY improved cardiac dysfunction; ameliorated myocardial hypertrophy, fibrosis and injury; and suppressed oxidative stress, inflammation and necroptosis via SIRT3 activation in STZ-induced diabetic mice, suggesting DHY may serve as a candidate for an agent to attenuate diabetic cardiomyopathy.

Botanical Origin of Galician Bee Pollen (Northwest Spain) for the Characterization of Phenolic Content and Antioxidant Activity.

Bee pollen is considered a natural product, relevant for its nutritional and antioxidant properties. Its composition varies widely depending on its botanical and geographical origins. In this study, the botanical characteristics of 31 bee pollen samples from Galicia (Northwest Spain) were analyzed; samples have not been studied until now from this geographical area. The study focused on the evaluation of the influence of plant origin on total phenol and flavonoid contents and antioxidant activity measured by radical scavenging methods. The multivariate statistical treatment showed the contribution of certain pollen types in the extract of bee pollen as to phenols, flavonoids and antioxidant capacity. Specifically, the bee pollen samples with higher presence of Castanea, Erica, Lythrum and Campanula type indicated higher total phenol and flavonoid contents and antioxidant activities according to the principal component analysis. On the contrary, Plantago and Taraxacum officinale type contributed a lower content of these compounds and radical scavenging activity. The cluster analysis classified the bee pollen samples into three groups with significant differences (p > 0.05) for the main pollen types, total phenol and flavonoid contents and antioxidant capacities. These results demonstrate the richness and botanical diversity in the pollen spectrum of bee pollen and enhance the possible beneficial nutraceutical properties of this beekeeping product.

Characterization, enzymatic and biological properties of a dominant lactic acid bacteria strain of Lactobacillus sakei subsp. sakei isolated from stinky mandarin fish

Presently in order to excavate suitability of resources of lactic acid bacteria for fermentation of mandarin fish, a strain of lactic acid bacteria (LAB), which was cultivated from stinky mandarin fish via using traditional MRS medium (CMC 1-8), was firstly isolated and purified. Subsequently, it was discovered that the as-harvested LAB was recognized as Lactobacillus sakei subsp. sakei with assistance of technology of phenotypic identifying and 16S rRNA sequencing. Concurrently, relevant characteristics in aspects of growth curve, acid production capacity, temperature and salt tolerance of Lactobacillus sakei subsp. sakei were plainly investigated. Furthermore, the preliminary research on protease properties and biological properties was revealed. The results unfolded that the strain could grow and produce acid normally at 37 °C, and deliver a strong tolerance even under 3% NaCl at 12 °C, which could be significant sufficiently to satisfy the low-temperature and salty fermentation of mandarin fish. The best compatible temperature and pH value for protease production were at 70 °C and 9.0, respectively. Resultantly, the main metabolites, containing polyphenols, flavonoids and soluble polypeptides, performed a remarkable effect on scavenging abilities of 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-picrylhydrazine (DPPH) free radical and ferricyanide reducing ability, of which the IC50 were 1.05, 6.87, and 4.62 mg/mL, respectively. And, the metabolites displayed partial inhibitory effects on Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus subtilis. Therefore, CMC 1-8 can potentially serve as a functional microorganism to directionally ferment mandarin fish.

Effect of postharvest visible spectrum LED lighting on quality and bioactive compounds of tomatoes during shelf life

The objective was to evaluate the effect of visible spectrum LED lighting during shelf-life on physicochemical quality and the main bioactive compounds of Kumato® cherry tomatoes. Tomatoes were stored 13 days at 5 °C under white (W), blue (B), blue + red (B + R), green + red (G + R), and green + far-red (G + FR) LED lights. Darkness (D) was used as control. Tomatoes under illumination showed higher weight losses and firmness decreases (30–35%). No chilling injury was observed. B + R lighting increased the carotenoid content by ∼27%, while G + R and G + FR reported an increase ∼30% in phenolics. B and B + R showed the highest increase in the phytochemical biosynthesis (lycopene and naringenin, as main carotenoid and flavonoid found) compared to D and W. Conclusively, illumination with B + R or B during shelf-life is recommended to enhance the main bioactive compounds. G + R and G + FR, also reported to be good elicitors of the phenolics and carotenoids biosynthesis.

Exploring the chemical composition and coloring qualities of cacao fruit epicarp extracts.

Cacao pod husks (CHs), the most abundant by-product of cacao beans production, can potentially become a source of functional ingredients for the food, cosmetic, and pharmaceutical industries. Three pigment samples (yellow, red, and purple) from lyophilized and ground cacao pod husk epicarp (CHE), were isolated by ultrasound-assisted solvent extraction, with yields between 11 and 14 wt%. The pigments exhibited UV-Vis flavonoid-related absorption bands at 283 nm and 323 nm and, only for the purple extract, reflectance bands in the 400-700 nm range. As per the Folin-Ciocalteu method, the CHE extracts contain high yields of antioxidant phenolic compounds amounting to 161.6, 153.9, and 167.9 mg GAE per g extract for the yellow, red, and purple samples, respectively. Phloretin, quercetin, myricetin, jaceosidin, and procyanidin B1 were among the main flavonoids identified by MALDI-TOF MS. A biopolymeric bacterial-cellulose matrix can effectively retain up to 541.8 mg of CHE extract per g of cellulose in dry weight. Also, MTT assays revealed that CHE extracts are non-toxic and increase viability in cultured VERO cells.

Enrichment of the flavonoid fraction from Eucommia ulmoides leaves by a liquid antisolvent precipitation method and evaluation of antioxidant activities in vitro and in vivo.

Eucommia ulmoides leaves originate from the dry leaves of the Eucommia ulmoides plant. Flavonoids are the main functional components of Eucommia ulmoides leaves. Some flavonoids such as rutin, kaempferol and quercetin are rich in Eucommia ulmoides, and they have outstanding antioxidant efficacy. However, the poor water solubility significantly affects the bioavailability of flavonoids. In this study, we used a liquid antisolvent precipitation (LAP) method to enrich the main flavonoid fractions in Eucommia ulmoides leaves, and prepared nanoparticles by the LAP method to increase flavonoids' solubility and antioxidant properties. The technological parameters were optimized by Box-Behnken Design (BBD) software and were displayed as follows: (1) total flavonoids (TFs) concentration: 83 mg mL-1; (2) antisolvent-solvent ratio: 11; (3) deposition temperature: 27 °C. Under optimal processing conditions, the purity and recovery rate of TFs were 88.32% ± 2.54% and 88.08% ± 2.13%, respectively. In vitro experiments showed that the radical scavenging IC50 values for DPPH, ABTS, hydroxyl radicals and superoxide anions were 16.72 ± 1.07, 10.76 ± 0.13, 227.68 ± 18.23 and 335.86 ± 15.98 μg mL-1, respectively. In vivo studies showed that the obtained purified flavonoid (PF) (100, 200, 400 mg kg-1) treatment is able to improve CCl4-induced liver and kidney damage through adjusting, superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) levels. These results demonstrated that the LAP method is capable of extracting TFs from Eucommia ulmoides leaves with high bioaccessibility.

Integrated Data Reveal the Flavonoid Biosynthesis Metabolic Pathway in Semen Ziziphi Spinosae Using Transcriptomic and Metabolomic

The extract from Semen Ziziphi Spinosae (SZS) contains many secondary metabolites (flavonoids, alkaloids, and terpenoids), widely reported for their high medicinal value. In order to know the number and type of flavonoids and the regulating mechanism of flavonoid biosynthesis during the growth and development of SZS, we identified and analyzed the flavonoid metabolites and genes in SZS using metabolomic and transcriptomic. A total of 13,232 differentially expressed genes and 83 flavonoid metabolites were identified at three different growth and development stages (T1, T2, and T3) of SZS. The main flavonoid metabolic components of SZS were catechin, L-epicatechin, (–)-epigallocatechin, (+)-gallocatechin, spinosin and its derivatives. A total of 53 unigenes encoding 15 enzymes were identified as candidate genes involved in flavonoid biosynthesis in SZS. Among, PAL, C4H, 4CL, CHS, CHI, FLS, FNS, ANS, ANR, LAR, and UFGT genes were all downregulated in T3 than in T1. The expression levels of these genes influence the accumulation of flavonoids in SZS. Our results should provide valuable information for flavonoid metabolites and candidate genes involved in flavonoid biosynthesis on SZS

Isolation, bioassay and 3D-QSAR analysis of 8-isopentenyl flavonoids from Epimedium sagittatum maxim. as PDE5A inhibitors

BackgroundAs known, inhibition of phosphodiesterase 5 (PDE5) has the therapeutic effect on male erectile dysfunction (ED), and the processed folium of Epimedium sagittatum Maxim. (PFES) characterized by 8-isopentenyl flavonoids is a famous herb for treating ED. However, the main flavonoids inhibitory activities, structure–activity relationship (SAR) and signaling pathway have been not systematically studied so that its pharmacodynamic mechanism is unclear.MethodsWe aimed to initially reveal the PFES efficacy mechanism for treating ED. For the first time, 6 main 8-isopentenyl flavonoids (1–6) from PFES were isolated and identified. Then based on HPLC detection, we proposed a novel method to screen inhibitors among them. We further analyze the three-dimensional quantitative structure–activity relationship (3D-QSAR) for those inhibitors.ResultsThe results were verified by cellular effects of the screened flavonoids. Among 6 compounds, Icariin: (1), 2-Oʹʹrhamnosylicaridide II (2) and Baohuoside I (3) were identified with significant activities (IC50 = 8.275, 3.233, 5.473 μM). Then 3D-QSAR studies showed that the replacement of C8 with bulky steric groups as isopentenyl, C3 with positive charge groups and C4' with a hydrogen bond acceptor substituent could increase inhibitory effects. In contrast, the substitution of C7 with bulky steric groups or hydrophilic groups tended to decrease the efficacies. And compounds 1, 2, 3 could increase cGMP level and decrease cytoplasmic Ca2+ of rat corpus cavernosum smooth muscle cells (CCSMCs)by activating PKG.Conclusion8-isopentenyl flavonoids could be the main pharmacodynamic substances of PFES in the treatment for ED, and some had significant PDE5A1 inhibitory activities so as to activate cGMP/PKG/Ca2+ signaling pathway in CCSMCs, that was related to the substituents at the key sites such as C8, C3, C4ʹ and C7 in the characteristic compounds.

Nelumbinis Stamen Ameliorates Chronic Restraint Stress-Induced Muscle Dysfunction and Fatigue in Mice by Decreasing Serum Corticosterone Levels and Activating Sestrin2.

Nelumbo nucifera Gaertn. is an important aquatic vegetable, and its dried stamen (Nelumbinis stamen, NS) is a valuable nutraceutical usually used as a herbal tea. Here, we used ultrahigh-performance liquid chromatography (UPLC)-quadrupole time-of-flight mass spectrometry and high-performance liquid chromatography (HPLC) to chemically profile NS and quantify their main constituent flavonoids, respectively. In total, 44 components were identified, including organic acids, flavonoids, monoterpene glycosides, and fatty acids. Experimental mice were induced with fatigue by exposure to chronic restraint stress (CRS) for 8 h daily for 15 days and then treated with an aqueous extract of NS (0.5 and 1 g/kg) via gavage. NS significantly mitigated CRS-induced skeletal muscle dysfunction and fatigue in mice possibly by lowering serum corticosterone levels and restoring Sestrin2 expression in the gastrocnemius to regulate metabolism, preserve mitochondrial homeostasis, and promote antioxidant capacity. These results demonstrate that NS can be used as a nutraceutical or supplement for controlling stress-induced muscle dysfunction and fatigue.

DEVELOPMENT OF METHODS OF STANDARDIZATION OF FLOWERS OF SPREADING MARIGOLD (TAGETES PATULA L.)

The spreading marigold (Tagetes patula L.), the family Aster (Asteraceae), or Composite (Compositae), is a prospective source of flavonoids. The aim of the study is to develop methods of standardization of marigold flowers rejected, consisting in determining the identity of this raw material and the quantitative determination of biologically active compounds. As a result of a comparative chromatographic study, the presence of flavonoids was detected upon detection at a wavelength of 254 and 366 nm and before and after reaction with an alcohol solution of aluminum chloride. The presence of patuletin and patulitrin was confirmed in extracts of different varietal forms of Tagetes patula L.. Using column chromatography on silica gel L 40/100, two flavonoid substances were isolated patuletin (3,5,7,3′,4′-pentahydroxy-6-methoxyflavone) and patulitrin (7-O-β-D-glucopyranoside of 3,5,7,3',4′-pentahydroxy-6-methoxyflavone), which have been identified by UV-, 1H-NMR -, 13C-NMR-spectroscopy and mass spectrometry, as well as acid hydrolysis. In the solvent system chloroform- ethanol-water (26 : 16 : 3) Rf values of patuletin and patulitrin are about 0.7 and 0.4, respectively. It was found that patulitrin is the main flavonoid in the flowers of spreading marigold and determines the character of the absorption curve of the electronic spectra of water-alcohol extraction from this raw material. During the quantitative analysis of the total flavonoids in the flowers of spreading marigold, it is necessary to recalculate the content of active substances to the dominant and diagnostically significant flavonoid patulitrin. It was determined that the content of the total flavonoids in the studied samples of flowers of different varieties of the spreading marigold varies from 4.36±0.02% to 11.71±0.05% (calculated on patulitrin).