Preparation,characterization and antioxidant activity analysis of three Maillard glycosylated bone collagen hydrolysates from chicken,porcine and bovine

Bone collagen hydrolysates(peptides)derived from byproduct of animal product processing have been used to produce commercially valuable products due to their potential antioxidant activity.Maillard glycosylated reaction is considered as a promising method to enhance the antioxidant activity of peptides.Hence,this research aims at investigating the Maillard glycosylation activity and antioxidant activity of bone collagen hydrolysates from different sources.In this study,3 glycosylated bone collagen hydrolysates were prepared and characterized,and cytotoxicity and antioxidant activity were analyzed and evaluated.The free amino groups loss,browning intensity,and fluorescence intensity of G-Cbcp(glycosylated chicken bone collagen hydrolysates(peptides))were the heaviest,followed by G-Pbcp(glycosylated porcine bone collagen hydrolysates(peptides))and G-Bbcp(glycosylated bovine bone collagen hydrolysates(peptides)).The results of amino acid analysis showed that amino acid composition of different bone collagen hydrolysates was significantly different and the amino acid decreased to different degrees after Maillard glycosylated reaction,which may lead to differences in Maillard glycosylated reaction activity.Furthermore,the 3 glycosylated hydrolysates showed no significant cytotoxicity.The results showed that glycosylation process significantly increased the antioxidant activity of bone collagen hydrolysates,and G-Cbcp showed the strongest antioxidant activity,followed by G-Pbcp and G-Bbcp.Therefore,compared with the bone collagen hydrolysates,3 glycosylated hydrolysates showed significant characteristic and structural changes,and higher antioxidant activity.

Antioxidant Activity and Phytochemical Screening in Acacia rigidula Benth. Leaves

This study aimed to compare the total phenolic content (TPC) and antioxidant activities of A. rigidula extracts. It also aimed to identify phenolic acids present in the extracts. The 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and ferric thiocyanate lipid peroxidation antioxidant assays were performed. High performance liquid chromatography was used to identify phenolic acids. There was no solvent effect on TPC nor on scavenging activities, and inhibition of lipid peroxidation (p > 0.05) among solvent extracts. On the other hand, 1:1:3 water: acetone: methanol extract (10.22 mg GAE/g sample) had significantly higher reducing potential than 50% ethanol extract (EE) (9.259 mg GAE/g sample) (p < 0.05);but EE was not significantly different from 80% methanol extract (9.781 mg GAE/g sample) (p > 0.05). Phenolic fraction designated as fraction 4 had the highest antioxidant activity (p < 0.05) with 69.49% ABTS scavenging activity and FRAP reducing potential, 22.26 mg of GAE/g sample. DPPH scavenging activities of fractions 4 (55.59%) and 5 (55.64%) were significantly higher than the other fractions (p A. rigidula extracts contain gallic, caffeic, vanillic, p-coumaric, salicylic acids and vanillin.

Total Alkaloid Content, Total Phenolic Content, In Vitro Antioxidant Activity, and Preliminary Antiglycemic Potential of the Methanol Extract from Mozambican Wild Fruits of Vangueria infausta

This study investigated the antioxidant activity and alpha-amylase inhibitory potential of the methanolic extract from Vangueria infausta fruits with the aim of exploring its therapeutic and nutritional applications. Bioactive compounds such as total phenolics (TPC) and total alkaloids (TAC) were analyzed. Antioxidant activity was assessed using the DPPH, ABTS, FRAP, Ferrozine, Phosphomolybdate, and Folin-Ciocalteu methods, while alpha-amylase inhibitory activity was determined using the 3,5-Dinitrosalicylic Acid (DNSA) and 2-chloro-p-nitrophenyl-α-D-maltotrioside (CNPG3) methods. The results revealed significant variations in antioxidant activity across the methods used, with IC50 values ranging from 318.42 to 1255.56 µg/mL. Alpha-amylase inhibition was also significant, with IC50 values ranging from 140.85 to 121.06 µg/mL. The TPC was found to be 95.6 mg of gallic acid equivalent per 100 g of dry powder, and the TAC was 0.188 mg of atropine equivalent per 100 g of dry powder. These findings suggest that Vangueria infausta possesses promising antioxidant and alpha-amylase inhibitory potential, indicating its potential application in antioxidant therapies and in the management of carbohydrate digestion.

Antioxidant Activity of Ethyl Acetate Extract of Amomum villosum Lour.

[Objectives]To study the antioxidant activity of the ethyl acetate extract of Amomum villosum Lour.[Methods]The removal rate of chelated iron ions,hydroxyl radicals,superoxide anion free radicals and DPPH free radicals by the ethyl acetate extract of A.villosum Lour.was determined by UV spectrophotometer.[Results]0.5000μg/mL ethyl acetate extract of A.villosum Lour.had the strongest ability to chelate with ferrous ions and to remove hydroxyl radicals,superoxide anion free radicals and DPPH free radicals.The ability to chelate with ferrous ions was 95.14%,and the removal rate of the above free radicals was 86.217%,81.44%,and 85.16%.[Conclusions]The ethyl acetate extract of A.villosum Lour.had a strong antioxidant effect,and its antioxidant capacity was related to the sample concentration,which provides a theoretical basis for its application in the development of antioxidant skin care products.

UV,five wavelengths fusion and electrochemical fingerprints combined with antioxidant activity for quality control of antiviral mixture

Aiming to ensure the consistency of quality control of Traditional Chinese Medicines(TCMs),a combination method of high-performance liquid chromatography(HPLC),ultraviolet(UV),electrochemical(EC)was developed in this study to comprehensively evaluate the quality of Antiviral Mixture(AM),and Comprehensive Linear Quantification Fingerprint Method(CLQFM)was used to process the data.Quantitative analysis of three active substances in TCM was conducted.A fivewavelength fusion fingerprint(FWFF)was developed,using second-order derivatives of UV spectral data to differentiate sample levels effectively.The combination of HPLC and UV spectrophotometry,along with electrochemical fingerprinting(ECFP),successfully evaluated total active substances.Ultimately,a multidimensional profiling analytical system for TCM was developed.

Antioxidant Activity of Polysaccharides in Yam Bulbils and Their Hypoglycemic Effect in Diabetic Mice

The polysaccharides in yam bulbils were extracted, and their antioxidant activity and hypoglycemic effect in diabetic mice were discussed. The results showed that the antioxidant activity of polysaccharides in yam bulbils was signifi- cantly enhanced with the increase of concentration; they showed a strong scaveng- ing ability against DPPH. and .OH, and the scavenging ability was dose dependent to some extent; the scavenging rates reached 91.15% and 89.06% respectively when the dose reached 4.0 mg/ml; the polysaccharides in yam bulbils significantly educed the blood glucose in model rice, and the hypoglycemic effect of large-dose polysaccharides was more obvious. The polysaccharides in yam bulbils has good antioxidant activity and hypoglycemic effect, which provides a new source for devel- opment of safe and natural food antioxidants and blood sugar-lowering agents.

Antioxidant activity,total phenolic,and resveratrol content in five cultivars of peanut sprouts

Objective: To investigate the change in total phenolic compounds, antioxidant activity,and resveratrol content of five different germinated peanut cultivars.Methods: The germinated sprouts of five peanut cultivars(Kalasin1, Kalasin2, Konkaen,Konkaen4, and Tainan9) were extracted with 80% ethanol and collected as crude extract.The antioxidant capacities were determined with 2,2-diphenyl-1-picrylhydrazyl and ferric ion reducing antioxidant power method.The total phenolic compound was measured using the Folin–Ciocalteau assay.The qualification and quantification of resveratrol was performed by high performance liquid chromatography method.Results: Among the five cultivars, a three-day germination of Kalasin1 showed the highest phenolic content [(40.67 ± 2.62) mg gallic acid/g dry weight], expressed the highest 2,2-diphenyl-1-picrylhydrazyl antioxidant value [(80.51 ± 1.47) mmol/L Trolox/g dry weight], and ferric ion reducing antioxidant power antioxidant value [(171.33 ± 8.59)mmol/L ascorbic acid/g dry weight].However, the high performance liquid chromatography result of Kalasin2 significantly increased to the highest resveratrol content of(6.44 ± 1.26) mg/g dry weight on the second day of germination.Conclusions: The variation of phytochemical content in the peanut sprout is due to the effect of the peanut cultivar and the germination period.

Effect of Postharvest UV-C Irradiation on Phenolic Compound Content and Antioxidant Activity of Tomato Fruit During Storage

Mature-green tomato fruit （Solanum lycopersicum cv. Zhenfen 202） were exposed to different UV-C irradiation at 2, 4, 8, and 16 kJ m-2 and then stored under the dark at 14°C and 95% relative humidity （RH） for 35 d. Of these four doses, UV-C irradiation at 4 and 8 kJ m-2 significantly increased total phenolic contents in present tomato fruit by 21.2 and 20.2%, respectively. Furthermore, UV-C irradiation at 4 or 8 kJ m-2 promoted the accumulation of total flavonoids and increased the antioxidant activity. 2 or 16 kJ m-2 UV-C irradiation also enhanced antioxidant activity, but to a lesser extent. Seven phenolic compounds, viz., gallic acid, （＋）-catechin, chlorogenic acid, cafferic acid, syringic acid, p-coumaric acid, and quercetin in tomato fruit were identified and quantified by HPLC. Gallic acid was the major phenolic compound in tomato fruit and significantly correlated with antioxidant activity. 4 or 8 kJ m-2 UV-C irradiation significantly increased the contents of gallic acid, chlorogenic acid, syringic acid, p-coumaric acid, and quercetin. The optimum dose of UV-C irradiation in terms of increased phenolic compound content and enhanced Antioxidant activity was determined to be 4 or 8 kJ m-2.

Measurement of total phenolic content and antioxidant activity of aerial parts of medicinal plant Coronopus didymus

Objective: To evaluate the total phenolic content and compare the antioxidant activity of various solvent extracts and fractions from the aerial parts of Coronopus didymus through various assays. Methods: Total phenolic content was determined using the Folin-Ciocalteu assay and the in vitro antioxidant activity of a number of different extracts was investigated in a dose-dependent manner with three different methods: the 2,2-diphenyl-1-picrylhydrazyl(DPPH), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt(ABTS) and ferric reducing antioxidant power(FRAP) assays. A flavone was isolated from the most active ethanolic extract with high antioxidant activity using size exclusion chromatography. IC_(50) values were calculated for the DPPH and ABTS methods. The FRAP activity was assessed in terms of μM Fe(II) equivalent. Results: The phenolic content was found to be highest in the ethanol extract(CDA Et; 47.8 mM GAE) and the lowest in the dichloromethane extract(CDA DCM; 3.13 mM GAE). The ethanol extract showed high radical scavenging activity towards DPPH and ABTS radicals with IC_(50) values of(7.80 × 10~2) and(4.32 × 10~2) μg/m L, respectively. The most active ethanol extract had a FRAP value of 1 921.7 μM Fe(Ⅱ) equivalent. The isolated flavone F10C(5,7,4'-trihydroxy-3'-methoxy flavone) was far more effective for scavenging free radicals in the DPPH and ABTS assays with IC_(50) of 43.8 and 0.08 μg/m L, than the standard trolox, with IC_(50) values of 97.5 and 21.1 μg/m L, respectively. In addition, the flavone F10C and the standard ascorbic acid had FRAP values of 1 621.7 and 16 038.0 μM Fe(Ⅱ) equivalents, respectively. Conclusions: The total phenolic content of extracts in decreasing order is ethanol extract(CDA Et)> acetone extract(CDA ACE)> phenolic extract(CDA MW)> n-hexane extract(CDA nHX)> chloroform extract(CDA CHL)> dichloromethane extract(CDA DCM). The ordering of extracts in terms of antioxidant activity from highest to lowest is CDA Et> CDA MW> CDA DCM> CDA CHL> CDA ACE> CDA nHX in DPPH, ABTS and FRAP assays. A significant relationship is found between antioxidant potential and total phenolic content, suggesting that phenolic compounds are the major contributors to the antioxidant activity of Coronopus didymus.

Comparison of forage yield,silage fermentative quality,anthocyanin stability,antioxidant activity,and in vitro rumen fermentation of anthocyanin-rich purple corn(Zea mays L.) stover and sticky corn stover

The objective of this study was to observe the forage yield, silage fermentative quality, anthocyanin stability, and antioxidant activity during the storage period and in vitro rumen fermentation of anthocyanin-rich purple corn （Zea mays L.） stover （PS） and sticky corn stover （SS）. Forage yield of corn stover was weighed and ensiled with two treatments： （1） hybrid sticky waxy corn stover （control）, and （2） hybrid purple waxy corn stover （treatment）. Samples were stored in mini-silos for periods of 0, 7, 14, 21,42, 63, 84, and 105 d. The results showed that PS had significantly higher （P〈0.05） yields of dry matter （DM）, organic matter （OM）, gross energy （GE）, crude protein （CP）, neutral detergent fiber （NDF）, acid detergent fiber （ADF）, and total anthocyanins than that of the SS. Anthocyanin-rich purple corn stover silage （PSS） showed higher （P〈0.05） levels of DM and CP relative to the sticky corn stover silage （SSS）. Although anthocyanin-rich PSS displayed a lower （P〈0.05） level of pelargonidin-3-glucoside （P3G）, it had higher （P〈0.05） levels of peonidin （Peo） and pelargonidin （Pel） compared to the control. Delphinidin （Del） and malvidin （Mal） were not detected in SSS during the ensilage period; in PSS, Del was no longer detected after 7 d of ensilage. Specifically, total anthocyanins in anthocyanin-rich PSS decreased rapidly （P〈0.05） prior to 7 d of ensilage, and then remained at relatively stable （P〉0.05） constants. Compared to the anthocyanin-rich PSS, SSS displayed significantly higher （P〈0.05） pH value and ammonia nitrogen （NH3-N） content. Propionic acid （PA） at 0 d and butyric acid （BA） during the entire study period were not detected, whereas anthocyanin-rich PSS showed a higher （P〈0.05） level of lactic acid （LA） than that of the SSS. Compared with the SSS extract, anthocyanin-rich PSS extract showed a higher （P〈0.05） level of 2,2-diphenyl-1-picryihydrazyl （DPPH） scavenging activity and displayed a lower （P〈0.05） half maximal inhibitory concentration （IC50） value. Moreover, anthocyanin-rich PSS reduced （P〈0.05） gas production （GP）, and displayed lower levels of immediately soluble fraction and ratio of acetic acid （AA） to PA at 12 h, but the other parameters were unaffected （P〉0.05） relative to the control. Taken together, the results indicated that： （1） anthocyanins could be stable in silage; （2） anthocyanin-rich PSS showed better silage fermentative quality and stronger antioxidant activity; and （3） anthocyanin-rich PSS had no negative effect on rumen fermentation parameters.

Chlorogenic acid loaded chitosan nanoparticles with sustained release property,retained antioxidant activity and enhanced bioavailability

In this study,chlorogenic acid(CGA),a phenolic compound widely distributed in fruits and vegetables,was encapsulated into chitosan nanoparticles by ionic gelation method.The particles exhibited the size and zeta potential of 210 nm and 33 mV respectively.A regular,spherical shaped distribution of nanoparticles was observed through scanning electron microscopy(SEM)and the success of entrapment was confirmed by FTIR analysis.The encapsulation efficiency of CGA was at about 59%with the loading efficiency of 5.2%.In vitro ABTS assay indicated that the radical scavenging activity of CAG was retained in the nanostructure and further,the release kinetics study revealed the burst release of 69%CGA from nanoparticles at the end of 100th hours.Pharmacokinetic analysis in rats showed a lower level of Cmax,longer Tmax,longer MRT,larger AUC0et and AUC0e∞for the CGA nanoparticles compared to free CGA.Collectively,these results suggest that the synthesised nanoparticle with sustained release property can therefore ease the fortification of food-matrices targeted for health benefits through effective delivery of CGA in body.

Characterization of Aroma-Active Components and Antioxidant Activity Analysis of E-jiao(Colla CoriiAsini)from Different Geographical Origins

E-jiao(Colla Corii Asini,CCA)has been widely used as a healthy food and Chinese medicine.Although authentic CCA is characterized by its typical sweet and neutral fragrance,its aroma components have been rarely investigated.This work investigated the aroma-active components and antioxidant activity of 19 CCAs from different geographical origins.CCA extracts obtained by simultaneous distillation and extraction were analyzed by gas chromatography-mass spectrometry(GC-MS),gas chromatography-olfactometry(GC-O)and sensory analysis.The antioxidant activity of CCAs was determined by ABTS and DPPH assays.A total of 65 volatile compounds were identified and quantified by GC-MS and 23 aroma-active compounds were identified by GC-O and aroma extract dilution analysis.The most powerful aroma-active compounds were identified based on the flavor dilution factor and their contents were compared among the 19 CCAs.Principal component analysis of the 23 aroma-active components showed 3 significant clusters.Canonical correlation analysis between antioxidant assays and the 23 aroma-active compounds indicates strong correlation(r=0.9776,p=0.0281).Analysis of aroma-active components shows potential for quality evaluation and discrimination of CCAs from different geographical origins.

Composition and antioxidant activity of anthocyanins isolated from Yunnan edible rose(An ning)

Edible roses(An ning)are a good source of anthocyanins and grown widely in Yunnan Province of China.In this study,the contents of anthocyanins and total phenol as well as the antioxidant activity of methanol extract from specific variety of rose were systematically investigated.The results showed that anthocyanins and total phenolic content of the petals were(353.56±2.50)mg cyanidin 3,5-diglucoside(Cy-3,5-diglu)equivalents and(2087.43±17.37)mg gallic acid equivalents(GAE)per 100 g fresh weight(FW),respectively.Totally,3 kinds of anthocyanins were detected and Cy-3,5-diglu was the predominant constituent which accounted for approximately 94.9%of total anthocyanins according to the analysis results of high performance liquid chromatography-photodiode array detection(HPLC-PAD).Data demonstrated that the extract from edible rose exhibited excellent ferric reducing capacity and free radical scavenging activity against both 2,2-diphenyl-1-picrylhydrazyl(DPPH)and 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt(ABTS).The equivalents of anthocyanins from roses on DPPH,ABTS and ferric reducing ability were 2089,639 mg and 1400 mg GAE per 100 g FW,respectively.The high anthocyanins content and excellent antioxidant activity suggested that Yunnan edible roses could be applied in food industry as a good source of natural pigments.©2013 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved.

Antioxidant Activity of Isothiocyanate Extracts from Broccoli

Isothiocyanates(ITCs) extracts were prepared from fresh broccoli.Their antioxidant properties were evaluated by using the in vitro bioassays,including superoxide anion radical( 2 O·-) ,hydroxyl radical(HO·-) and 2,2-diphenyl-1-picrylhydracyl(DPPH·) radical-scavenging methods,lipid peroxidation assay,and reducing power assay.The ITCs extracts exhibited significant dose-dependent antioxidant activities(P<0.01) .Its antioxidant-stability was affected by temperature and storage condition,although it was more stable than vitamin C(Vc) .GC-MS iden-tified sulforaphane in the ITCs extracts.The antioxidant activity of sulforaphane was approximately one tenth to one fifth of that of Vc.Sulforaphane was experimented to be one of dominating contributors to antioxidant capacity of ITCs extracts.However,there was no direct antioxidant activity found for benzyl isothiocyanate(BITC) in vitro. Therefore,it could be concluded that the general group(-N=C=S) was not the essential part for the antioxidant activity of sulforaphane.It is suggested that the ITCs extracts from broccoli can be developed into a promising food additive for healthy food.

Synthesis of Hydroxystilbene Derivatives and their Antioxidant Activity by DPPH Method

Five hydroxystilbene derivatives were synthesized and their structures were determined using high-resolution mass spectrometry, ^1H NMB, and IR. In this study, the antioxidant activities of eight hydroxystilbenes （five synthesized hydroxystilbene derivatives and three other compounds） were evaluated with the free radiced scavenging model 1,1-diphenyl-2-picrylhydraxyl. It was observed that there exists a very significant linear rehtionship between the reciprocal of the EC50 value of each of the compounds and the maximum wavelength of the ultraviolet absorption peaks, It is believed that this result will be helpful for the further synthesis of such antioxidants.

Resveratrol elongates the lifespan and improves antioxidant activity in the silkworm Bombyx mori

A number of research has shown that the plant polyphenol resveratrol,one of the most prominent small molecules,has beneficial protective effects in multiple organisms,including worms,flies,and killifish.To understand the effects of resveratrol on lifespan,we evaluated its effects in the silkworm Bombyx mori.In this study,we found that lifespan was significantly prolonged in both female and male silkworms treated with resveratrol.Silkworm larval weight was significantly increased from day 3 of the 5th larval instar(L5D3)to day 7 of the 5th larval instar(L5D7).However,the weight of the pupa,cocoon,and total cocoon was not significantly different in female silkworms with resveratrol treatment than that in controls.Meanwhile,resveratrol significantly improved the thermotolerance of the silkworms,which enhanced their survival rate.Moreover,antioxidant activity was increased by resveratrol in both female and male silkworms.Furthermore,an antioxidant-related signalling pathway,SIRT7-FoxO-GST,was activated in silkworms with resveratrol treatment.Collectively,these results help us to understand the molecular pathways underlying resveratrol induced pro-longevity effects and indicate that silkworm is a promising animal model for evaluating the effects of lifespan-extending drugs.

Antihypertensive and antioxidant activity of Cassytha filiformis L.:A correlative study

Objective: To study the blood pressure lowering effect of Cassytha filiformis extract in animal models of hypertension and its correlation with the antioxidant activity.Methods: Male Sprague–Dawley rats were divided into two groups: endocrine hypertension(HTN group) that received a combination of prednisone and salt for two weeks and oxidative stress-associated hypertension(HTN-OS group) that received additional induction of L-Nitro Arginine Methyl Esther(L-NAME) for two days. Each group was subdivided into 4 and treated intravenously with the extract 5; 10; and 20 mg/kg, and vehicle control. The systolic blood pressure(SBP), diastolic blood pressure(DBP), and mean arterial pressure(MAP) were recorded. The blood was taken before and at the end of recording for the measurement of serum concentration of nitric oxide(NO). The changes of blood pressure were analyzed by two-way ANOVA while its correlation with NO concentration was analyzed by Pearson's Correlation.Results: The study showed a significant antihypertensive effect of the extract as compared with control group(P < 0.05) in both hypertensive models. Extract in the dose of 5 mg/kg showed the best blood pressure lowering effect. However, the correlation analysis did not show an association between NO increase and blood pressure lowering effect(P > 0.05).Conclusions: The study concludes that C. filiformis extract in the dose of 5 mg/kg exhibits the best blood pressure lowering effect in both animal models. Antihypertensive activity of the extract is not correlated with its antioxidant effect.

The Flavor and Antioxidant Activity Change Pattern of Shrimp Head Paste During Fermentation

To study the changes of volatile compounds and antioxidant activity of fast fermented shrimp head paste during the fermentation processing,Penaeus vannamei boone head was used as the raw material,and compound starter was added for fermen-tation.During the 14 days of fermentation,the changes of free amino acids,volatile flavor compounds and main components were determined by SPME-GC-MS and electronic nose.The oxidation-resistance changes of water extract at different fermentation stages were evaluated.The results showed that the total free amino acids increased from original 2320 to 5640 mg(100 mL)^(−1).SPME-GC-MS analysis found that aldehydes,pyrazine compounds increased from 10.80%,1.94%to 24.35%,13.63%respectively during the fermentation process.The HO·scavenging ability of shrimp head paste increased from 52%to 86%.Our results showed that the shrimp paste produced from shrimp head fermentation could obtain good flavor and possess certain antioxidant activity of aquatic fermented condiment.

Investigation of in vitro antioxidant activity of dihydromyricetin and flavonoids rich extract from vine tea(Ampelopsis grossedentata)

Background:Vine tea from fermented Ampelopsis grossedentata leaves has been used as a herbal tea and folk medicine in the southern region of China for hundreds of years.The aim of this investigation was to analyze the total flavonoids found in vine tea,including three bioactive flavonoids,and the total phenolic contents in the aqueous methanol extracts of 10 vine tea samples.In addition,this study also aimed to examine the antioxidant activity of dihydromyricetin and vine tea’s flavonoid-rich extract.Methods:The total flavonoids and total phenolic content assay of extracts from vine tea were performed by ultraviolet-visible spectroscopy and epoch microplate spectrophotometer,respectively.Three bioactive flavonoids were quantified simultaneously using high performance liquid chromatography.The antioxidant activity of dihydromyricetin and vine tea’s flavonoid-rich extract was evaluated in vitro using six different methods.Results:Vine tea contained a large number of flavonoids,with dihydromyricetin as its main constituent.The flavonoid-rich extract exhibited a significant scavenging effect on superoxide anion radicals,and on 3-ethylbenzthiazoline-6-sulphonic acid and 1,1-diphenyl-2-picrylhydrazyl radicals.It also possessed definite activity in lipid peroxidation inhibition,ferric reduction,and the moderation of Fe2+ion chelation ability.There was a significant negative correlation between dihydromyricetin content and antioxidant activity in the vine tea samples,including superoxide anion radical scavenging activity(P=−0.754,P<0.05),lipid peroxidation inhibition activity(P=−0.759,P<0.05),ferric-reducing antioxidant power(P=−0.843,P<0.01),respectively.Dihydromyricetin played a dominant role in the antioxidant activities of the flavonoid-rich extract.Conclusion:Vine tea’s flavonoid-rich extract could be used as a new antioxidant source to safeguard against oxidative stress.

Antioxidant activity and hepatoprotective effect of 10 medicinal herbs on CCl4-induced liver injury in mice

BACKGROUND Many natural products confer health benefits against diverse diseases through their antioxidant activities.Carbon tetrachloride(CCl4)is often used in animal experiments to study the effects of substances on liver injury and the related mechanisms of action,among which oxidative stress is a major pathogenic factor.AIM To compare antioxidant and hepatoprotective activities of ten herbs and identify and quantify phytochemicals for the one with strongest hepatoprotection.METHODS The antioxidant activity of ten medicinal herbs was determined by both ferricreducing antioxidant power and Trolox equivalent antioxidant capacity assays.The total phenolic and flavonoid contents were determined by Folin–Ciocalteu method and aluminum chloride colorimetry,respectively.Their effects on CCl4-induced oxidative liver injury were evaluated and compared in a mouse model by administrating each water extract(0.15 g/mL,10 mL/kg)once per day for seven consecutive days and a dose of CCl4 solution in olive oil(8%,v/v,10 mL/kg).The herb with the strongest hepatoprotective performance was analyzed for the detailed bioactive components by using high-performance liquid chromatography-electrospray ionization source-ion trap tandem mass spectrometry.RESULTS The results revealed that all tested herbs attenuated CCl4-induced oxidative liver injury;each resulted in significant decreases in levels of serum alanine transaminase,aspartate transaminase,alkaline phosphatase,and triacylglycerols.In addition,most herbs restored hepatic superoxide dismutase and catalase activities,glutathione levels,and reduced malondialdehyde levels.Sanguisorba officinalis(S.officinalis)L.,Coptis chinensis Franch.,and Pueraria lobata(Willd.)Ohwi root were the three most effective herbs,and S.officinalis L.exhibited the strongest hepatoprotective effect.Nine active components were identified in S.officinalis L.Gallic acid and(+)-catechin were quantified(7.86±0.45 mg/g and 8.19±0.57 mg/g dried weight,respectively).Furthermore,the tested herbs displayed a range of in vitro antioxidant activities proportional to their phenolic content;the strongest activities were also found for S.officinalis L.CONCLUSION This study is of value to assist the selection of more effective natural products for direct consumption and the development of nutraceuticals or therapeutics to manage oxidative stress-related diseases.