Optimization of Extraction Process for Total Flavonoids from Penthorum chinense Pursh and Comparison of Their Contents from Different Parts

[Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experiments were designed to optimize the extraction process of total flavonoids from P.chinense Pursh with the volume fraction of ethanol,the ratio of material to liquid,heating reflux extraction time and extraction times as factors,and the content of total flavonoids as the index.A verification test was carried out.The optimized extraction process was adopted to compare the contents of total flavonoids from different parts of P.chinense Pursh.[Results]The best extraction process was extracting the powder of P.chinense Pursh for 2.0 h with 20 times of 55%ethanol by reflux twice.Under this condition,the contents of total flavonoids were 3.63%,8.90%,11.28%,and 4.36%from stems,leaves,flowers and whole grass of P.chinense Pursh,respectively.[Conclusions]The process is reasonable,feasible and stable,and can effectively extract total flavonoids from P.chinense Pursh.The contents of total flavonoids from different parts of P.chinense Pursh were quite different,and the value was higher in the leaves and flowers,so the proportions of leaves and flowers should be paid attention to in the industrial processing of P.chinense Pursh.

Analysis of Lavandulyl Flavonoids from Sophora flavescens with Antiinflammatory Activity Based on Molecular Network Technology

[Objectives]This study was conducted to screen lavandulyl flavonoids with anti-inflammatory activity from Sophora flavescens.[Methods]35 compounds were screened from traditional Chinese medicine S.flavescens using the nitric oxide(NO)anti-inflammatory activity model.[Results]Five components,8(xanthohumol),13(kurarinol),27(4-methoxysalicylic acid),28(b-resorcic acid)and 30(b-resorcic acid),exhibited significant anti-inflammatory activity,with IC 50 values of 5.99,4.76,6.96,3.41 and 5.22μM,respectively.Especially,8(xanthohumol)and 13(kurarinol)were typical lavandulyl flavonoids in S.flavescens,which were worth further exploration.Furthermore,UPLC-Q-Exactive and GNPS molecular networking technique were used for rapid analysis of lavandulyl flavonoids from S.flavescens.A total of 15 components were identified.[Conclusions]This work lays a theoretical foundation for further separation and analysis of lavandulyl flavonoids with anti-inflammatory activity from S.flavescens.

The Protective Effects of Flavonoids from Scutellaria Baicalensis Georgi Stems and Leaves on Oligodendrocyte Damage Induced by Aβ1-42

Aim: This study aimed to investigate the protective effects of flavonoids from the stem and leaves of Scutellaria baicalensis Georgi (SSFs) against Aβ1-42-induced oligodendrocytes (OL) damage. Methods: Immunofluorescence was used for the detection of myelin-associated glycoprotein (MAG), a characteristic protein of rat oligodendrocytes (OLN-93 cells). To evaluate the potential protective effects of SSFs on OLN-93 cells injured by Aβ1-42, an injury model was established by subjecting OLN-93 cells to Aβ1-42 exposed. Cell morphology was examined using an inverted microscope, while cell viability was assessed using the colorimetric method of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Additionally, lactate dehydrogenase (LDH) was measured using the pyruvic acid reduction assay. The Ginkgo biloba leaf extract (GBE) injection was used as a positive control. Results: A total of >95% of the MAG immunofluorescence-positive cells were identified as oligodendrocytes. Gradually increasing concentrations of SSFs impaired the cells, and the maximum nondetrimental dose for OLN-93 cells was 75 mg/L. This study assessed the effects of SSFs on OLN-93 cells damaged by Aβ1-42. The results indicated that SSFs significantly improved OLN-93 cell morphological abnormal changes, increased the OLN-93 cell survival rate, and reduced LDH release. Conclusion: SSFs can alleviate Aβ1-42-induced damage of OL.

Research Progress in the Extraction and Application of Flavonoids from Ginkgo biloba Leaves

Ginkgo biloba resources in China are enormous. With the demand of the market, the preparation and application of flavonoids have become a current research hotspot. The main active substances in G. biloba leaves, flavonoids, have various functional activities and are widely used in fields such as food, medicine, cosmetics, feed, etc. In this paper, the introduction, functional activity, extraction methods, and application research of flavonoids from G. biloba leaves are reviewed, and the development prospects of flavonoids from G. biloba leaves are expected.

Multidisciplinary strategies to enhance therapeutic effects of flavonoids from Epimedii Folium:Integration of herbal medicine,enzyme engineering,and nanotechnology

Flavonoids such as baohuoside I and icaritin are the major active compounds in Epimedii Folium(EF)and possess excellent therapeutic effects on various diseases.Encouragingly,in 2022,icaritin soft capsules were approved to reach the market for the treatment of hepatocellular carcinoma(HCC)by National Medical Products Administration(NMPA)of China.Moreover,recent studies demonstrate that icaritin can serve as immune-modulating agent to exert anti-tumor effects.Nonetheless,both production efficiency and clinical applications of epimedium flavonoids have been restrained because of their low content,poor bioavailability,and unfavorable in vivo delivery efficiency.Recently,various strategies,including enzyme engineering and nanotechnology,have been developed to increase productivity and activity,improve delivery efficiency,and enhance therapeutic effects of epimedium flavonoids.In this review,the structure-activity relationship of epimedium flavonoids is described.Then,enzymatic engineering strategies for increasing the productivity of highly active baohuoside I and icaritin are discussed.The nanomedicines for overcoming in vivo delivery barriers and improving therapeutic effects of various diseases are summarized.Finally,the challenges and an outlook on clinical translation of epimedium flavonoids are proposed.

Extraction,Antioxidant Activity and Identification of Flavonoids from Root Tubers of Kosteletzkya virginica

Kosteletzkya virginica(K.virginica)is used for revegetation of salt-affected coastal tidal flats and as a raw material of biodiesel.K.virginica root tuber,a biowaste with low economic value,is rich in bioactive compounds.This study aimed to extract and identify flavonoids from K.virginica root tubers.The optimal extraction conditions were 1/25(w/v)solid/liquid ratio,40%ethanol concentration at 40℃ for 60 min.Under these conditions,65.2±3.7 mg/g total flavonoid content was extracted from the roots,which were collected from salinized soil in late autumn of the third year.Antioxidant activity was evaluated through 1,1-diphenyl-2-picrylhydrazyl,hydroxyl radical,and superoxide anion scavenging assays.The extracted flavonoids exhibited antioxidant activity in a dose-dependent manner.Five flavonoids,glucoliquiritin apioside,licoisoflavone B,5-methoxy-7,8-diprenylflavone,7,2′-dihydroxy-6,8-dimethyl-4′,5′-methylenedioxyflavan,and 5,7,4′-trihydroxy-3′-methoxy-6,8-di-Cmethylflavanone,were identified by ultra-performance liquid chromatography–tandem mass spectrometry.Our results suggest that the flavonoids of K.virginica root tubers might be potent antioxidants and can be effectively applied as an ingredient in food and natural medicine.

Optimization of Extraction Conditions for Total Flavonoids from Fructus Aurantii Immaturus and Its Anti-UVB Radiation Activity

[Objectives]Optimum extraction conditions of total flavonoids from Fructus Aurantii Immaturus(TFFAI)and its resistance activity to ultraviolet radiation were investigated in present research.[Methods]The optimal extraction conditions of TFFAI were determined by single factor and orthogonal experiments,and the survival rate of TFFAI on HaCaT cells irradiated with UVB rays was investigated.It s antioxidant capacity was determined by ABTS.[Results]The results showed that the highest yield of TFFAI was obtained with 70%ethanol at a solid-to-liquid ratio of 1:50(w/v)and 40℃for 1.5 h by single-factor and orthogonal experiments.Total flavonoids(0.25-1.00 mg/ml)could significantly improve the survival rate of HaCaT cell line.Meanwhile,the maximum absorption peak of TFFAI was found at 283 nm,and in-vitro antioxidant experiment identified that TFFAI had a good clearance rate to ABTS.It suggestes that TFFAI could protect the cells from UVB damage by absorption of UVB rays and anti-oxidation.[Conclusions]TFFAI played a protective role on UVB irradiated cells through UVB ultraviolet absorption and antioxidant pathways.

Research Progress of Total Flavonoids from Plants in Trib.Lorantheae

Trib.Lorantheae is one of the important medicinal plants in traditional medicine.There are 41 genera,6 genera of which are produced in China,mainly distributed in Southwest China,South China and Central South China.There are many kinds of plants in this family,and 22 species can be used as Chinese medicinal materials in China.The branches and leaves of Trib.Lorantheae are rich in flavonoids,alkaloids,terpenoids,polysaccharides,organic acids and other functional substances,among which flavonoids are one of the important chemical components to exert pharmacological activity,and play an important role in hypoglycemic,lipid-lowering,anti-inflammatory,anti-tumor,anti-oxidation,anti-osteoporosis and so on.In this paper,the chemical composition,extraction method,component analysis and pharmacological action of flavonoids in Trib.Lorantheae plants were reviewed,in order to provide scientific reference for further development and clinical application of flavonoids in Trib.Lorantheae plants.

Flavonoids from the stems and leaves of Scutellaria baicalensis Georgi attenuate H_2O_2-induced oxidative damage to rat cortical neurons

Primary cultures of rat cortical neurons were treated with H2O2 in an in vitro model of free radical neurotoxicity. Flavonoids extracted from the stems and leaves of Scutellaria baicalensis Georgi, known as SSF, at concentrations of 18.98, 37.36 and 75.92 μg/mL, protected neurons against H2O2 injury in a dose-dependent manner. SSF increased cell survival, reduced lactate dehydrogenase release and inhibited malondialdehyde production. SSF also inhibited reductions in superoxide dismutase, glutathione peroxidase and Na＋-K＋-ATPase activities. These results in-dicate that SSF can protect rat cortical neurons against H2O2-induced oxidative injury.

Protective Effects of Flavonoids from Pteridium aquilinum on CCl_(4)-induced Acute Liver Injury in Mice

[Objectives]To explore the protective effects of flavonoids from Pteridium aquilinum(PAFL)on carbon tetracholoride(CCl_(4))-induced acute liver injury in mice and its potential mechanism.[Methods]All mice were randomly divided into four groups(n=10 in each),normal group,CCl_(4)group,CCl_(4)+PAFL groups[treated with PAFL(50 or 200 mg/kg)].Animal treatment was continued for 7 consecutive days.The blood was collected after injection of CCl_(4)for 24 h,and the liver tissue was removed from the mice and stored at-80℃.[Results]The PAFL(50 and 200 mg/kg)significantly inhibited the increase of aspartate aminotransferase(AST)and alanine aminotransferase(ALT)levels in serum caused by CCl_(4)treatment.PAFL administration not only increased the activity of antioxidant enzymes superoxide dismutase(SOD),Glutathione(GSH)and catalase(CAT)in mice,but also reduced the level of malondialdehyde(MDA).Meanwhile,PAFL administration decreased the expression of nuclear factor-kappa B(NF-κB)and Cyclooxygenase-2(COX-2)proteins and inhibited the release of pro-inflammatory factors tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β)and interleukin 6(IL-6).In addition,PAFL(200 mg/kg)treatment down-regulated extracellular regulated protein kinases(ERK)and c-Jun N-terminal kinase(JNK)protein levels in liver tissue.[Conclusions]These findings clearly indicate that the protective effects of PAFL on CCl_(4)-induced acute liver injury is related to its antioxidant and anti-inflammatory activity,which may be mediated by NF-κB and MAPKs signaling pathways.

Dynamic Microwave-assisted Extraction of Flavonoids from Radix Scutellariae

Dynamic microwave-assisted extraction（DMAE） of flavonoids from Radix Scutellarie was described in this article. A TM010 microwave resonant cavity was used as the energy coupler. Several parameters of DMAE, including concentration, flow rate, volume of the extraction solvent, and irradiation power, were optimized. The extraction was performed under the optimum conditions for the extraction of total flavonoids. The total flavonoids were determined by UV-Vis spectrophotometry. The main bioactive components, including baicalin, baicalein, and wogonin, were determined by HPLC. The extraction yields of the tlavonoids obtained by DMAE were compared with those obtained by pressurized microwave assisted extraction （ PMAE）, ultrasonic extraction （ UE ）, soxhlet extraction （ SE ）, and reflux extraction（ RE）, and these results indicate that DMAE is a good alternative method for the extraction of flavonoids from Radix Scutellade.

Isolation and Extraction of Total Flavonoids from Epimedium Koreanum Nakai by Supercritical Fluid Extraction

In the present paper is reported the method for the isolation and extraction of total flavonoids of Epimedium Koreanum Nakai by means of supercritical fluid extraction(SFE). By examining pressure, temperature, amounts of modifier and extraction time, the optimized condition of SFE is confirmed as 30 MPa and 60 ℃, with 70% ethanol as the modifier. The samples were statically extracted for 30 min, followed by dynamic extraction for 120 min at a flow rate of 6 mL/min. The quantitative analysis of total flavonoids was performed by UV-Vis spectrophotometry. Compared with the conventional method, the SFE method is more efficient, more rapid and more friendly environmentally.

Mechanisms underlying attenuation of apoptosis of cortical neurons in the hypoxic brain by flavonoids from the stems and leaves of Scutellaria baicalensis Georgi

Flavonoids from the stems and leaves of Scutellaria baicalensis Georgi, an antioxidant, markedly improve memory impairments and neuronal injuries. In the present study, primary cortical neurons of rats were exposed to potassium cyanide to establish a model of in vitro neural cell apoptosis. Inhibition of apoptosis by flavonoids from the stems and leaves of Scutellaria baical- ensis Georgi at concentrations of 18.98, 37.36, and 75.92 gg/mL was detected using this model. These flavonoids dramatically increased cell survival, inhibited cell apoptosis and excessive pro- duction of malondialdehyde, and increased the activities of superoxide dismutase, glutathione peroxidase, and Na＋-K＊-ATPase in primary cortical neurons exposed to potassium cyanide. The flavonoids from the stems and leaves of Scutellaria baicalensis Georgi were originally found to have a polyhydric structure and to protect against cerebral hypoxia in in vitro and in vivo models, including hypoxia induced by potassium cyanide or cerebral ischemia. The present study suggests that flavonoids from the stems and leaves of Scutellaria baicalensis Georgi exert neuroprotective effects via modulation of oxidative stress, such as malondialdehyde, superoxide dismutase, glutathione peroxidase and Na＋-K＋-ATPase disorders induced by potassium cyanide.

Supercritical Fluid Extraction of Total Flavonoids from Leaves of Acanthopanax Senticosus Harms

The herbal plant Acanthopanax Senticosus Harms is natural herb of Changbaishan in Jilin Province of China, which belongs to the Araliaceae family. As the ingredients of folk medicine, it has long been used to treat a variety of human diseases, such as cerebrovascular disease, diabetes, tumor, isochemic heart diseases, hypertension, rheumatic arthritis, etc. E2,33. Flavonoids, a class of constituent compounds, which have a broad distribution in the nature and are found in Acanthopanax Senticosus Harms, have gained particular attention. A number of studies have shown that flavonoid compounds have wide biological activities, such as anti-aging, anticancer, anti-HIV,

Optimization of conditions for supercritical fluid extraction of flavonoids from hops (Humulus lupulus L.)

Waste hops are good sources of flavonoids. Extraction of flavonoids from waste hops (SC-CO2 extracted hops) using supercritical fluids technology was investigated. Various temperatures, pressures and concentrations of ethanol (modifier) and the ratio (w/w) of solvent to material were tested in this study. The results of single factor and orthogonal experiments showed that at 50 °C, 25 MPa, the ratio of solvent to material (50%), ethanol concentration (80%) resulted in maximum extraction yield fla- vonoids (7.8 mg/g). HPLC-MS analysis of the extracts indicated that flavonoids obtained were xanthohumol, the principal prenylflavonoid in hops.

Impact Factor:1.90 Total flavonoids from Saussurea involucrata attenuate inflammation in lipopolysaccharide-stimulated RAW264.7 macrophages via modulating p65,c-Jun,and IRF3 signaling pathways

Objective:To investigate the anti-inflammatory effects of the total flavonoids from Saussurea involucrata on lipopolysaccharides(LPS)-stimulated murine RAW264.7 macrophages and explore its underlying mechanism of action.Methods:Total flavonoids from Saussurea involucrata were extracted using chromatographic column method.Cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay.The production of nitric oxide was detected by Griess assay and the release of cytokines(IL-10 and TNF-α)and chemokines(MCP-1,MIP-1α,and CCL5/RANTES)was determined by ELISA to evaluate the anti-inflammatory activity of total flavonoids from Saussurea involucrata.Moreover,nuclear translocation of p65,c-Jun,and IRF3 was detected by immunofluorescence microscopy and Western blotting analysis was performed to determine the expression of related proteins.Results:Total flavonoids extracted from Saussurea involucrata were 751.5 mg/g and the content of rutin was 506.5 mg/g.The production of inflammatory mediators including nitric oxide,cytokines,and chemokines was effectively inhibited by total flavonoids from Saussurea involucrata.Meanwhile,total flavonoids also suppressed the nuclear translocation of p65,c-Jun,and IRF3 in LPS-stimulated RAW264.7 cells.The LPS-induced expression of iNOS and COX-2 was remarkably reduced by treatment with total flavonoids from Saussurea involucrata.Moreover,total flavonoids decreased the expression levels of p-IKKα/β,p-TBK1,p-p38,p-ERK,p-JNK,p-p65,p-c-Jun,and p-IRF3 in LPS-exposed RAW264.7 macrophages.Conclusions:Total flavonoids from Saussurea involucrata potentially inhibit the secretion of pro-inflammatory mediators,which may be related to inhibition of p65,c-Jun,and IRF3 signaling pathways in LPS-stimulated RAW264.7 cells.

Optimization of Extraction of Total Flavonoids from HERBA BLUMEAE RIPARIAE Using Response Surface Methodology

[Objectives]This study aimed to optimize the ultrasonic-assisted extraction process of total flavonoids from a Zhuang medicine HERBA BLUMEAE RIPARIAE using response surface methodology.[Methods]Using rutin as a reference substance,a standard curve was drawn at a wavelength of 292 nm.Content determination was performed through absorbance under different conditions.The effects of ultrasonic time,ethanol volume fraction and liquid-to-solid ratio on the yield of total flavonoids from HERBA BLUMEAE RIPARIAE were investigated by single-factor tests.By using Box-Behnken test,the ultrasonic-assisted extraction process of total flavonoids from HERBA BLUMEAE RIPARIAE was optimized.[Results]The optimal extraction process of total flavonoids from HERBA BLUMEAE RIPARIAE was as follows:ultrasonic time of 30 min,ethanol volume fraction of 50%and liquid-to-solid ratio of 40∶1(mL/g).Under the optimal extraction conditions,the average yield of total flavonoids from HERBA BLUMEAE RIPARIAE was 85.47 mg/g.[Conclusions]The optimized extraction process was convenient and feasible.This study will provide a reference for the extraction of total flavonoids from HERBA BLUMEAE RIPARIAE,and provide certain guidance and basis for further development and utilization of the plan resource of Blumea riparia(Bl.)DC.

Antifungal Flavonoids from Ficus sarmentosa var. henryi (King) Corner

The methanol extract of Ficus sarmentosa var. henryi （King） Corner was found to detect potent inhibitory activities against 6 crop pathogenic fungi, Fusarium graminearum, Pumpkin fusarium Wilt, Curvularia lunata （Wakker） Boed, Septoria zeicola Stout, Botrytis cinerea, and Rhizoctonia solani. Four flavonoids were isolated from the extract of F. sarmentosa var. henryi by activity-guided fractionation and they were identified as eriodictyol （1）, homoeriodictyol （2）, dihydroquercetin （3）, and luteolin （4） by spectroscopic means and displayed excellent inhibitory activity against F. graminearum and S. zeicola. Among them, luteolin （4） showed the strongest inhibitory activity with IC50 values of 56.38 and 81.48 mg L^-1, to the fungi, respectively. The in vitro inhibitory activity of F. sarmentosa var. henryi （King） Corner was reported for the first time and the inhibitory action mechanism of luteolin （4） was worthy of further research.

Efficacious anti-cancer property of flavonoids from citrus peels

Cancer is one of the two leading human fatal diseases.Drug development for cancer intervention has progressed well in past decades yet existing drugs face many limitations in applications and effectiveness and are often associated with serious of side effects,which can further deteriorate the patients’quality of life.Recent development of natural product based and therapeutically sound anti-cancer agents have gained popularity in the field of functional foods,in which a few have demonstrated efficacy and minimal toxicity toward the prevention and treatment of carcinogenesis.With multiple active molecular components,citrus peels and derived extracts have demonstrated potent efficacious properties against various cancers due in large part to the rich content of flavonoids present in citrus peels.This review summarizes the results of currently available data regarding the in vivo anti-cancer activity of citrus peel flavonoids,and identifies opportunities for subsequent human clinical trials to assess preventive and therapeutic effects in the near future.

Separation and Identification of Flavonoids from Fistular Onion Stalk(Allium fisturosum L.var.Caespitosum Makio)

The chemical constituents of fistular onion stalk obtained by supercritical CO2 extraction were separated and purified by silica gel and sephadex LH-20 gel column chromatography and the preparative TLC method and four flavonoids were obtained. On the basis of the spectral data, they were structurally identified as （＋）-catechin, （-）-epieatechin, astragalin, and 3-O-β-D（2-O-β-D-glu- copyranosyl）-glucopyranosides of kaempferol.