[ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging sub...[ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging substances from sweet potato leaves were optimized by orthogonal test and the bioactive components in extracts were investigated by correlation analysis. [ Result] Sweet potato leaves contain the bioactive substances scavenging DPPH free radical and hydroxyl free radical. Extracting solvent species is the most important factor that influencing extraction yield. The optimal extraction and storage conditions are as following: water as solvent, pH 8.0 of extracting liquid, storage at 25 ℃. There is a good positive linear relationship between the content of total phenols in sweet potato leaves and corresponding scavenging rates against both the DPPH free radical and hydroxyl free radical. For the content of total flavones in sweet potato leaves, just a correlation with scavenging rate against hydroxyl free radical shown in test. [ Conclusion] The phenols in ex- tracts could effectively scavenge both the DPPH free radical and hydroxyl free radical, whereas the flavones in extracts can only function on the hydroxyl free radical.展开更多
A crude polysaccharide was extracted from Physalis alkekengi L. fruit. HPLC was used for the component analysis of the polysaccharide. The results indicate that Physalis alkekengi L. polysaccharide(PAP) was composed...A crude polysaccharide was extracted from Physalis alkekengi L. fruit. HPLC was used for the component analysis of the polysaccharide. The results indicate that Physalis alkekengi L. polysaccharide(PAP) was composed of rhamnose, xylose, arabinose, galactose, and glucose. Free radicals scavenging activity of PAP was studied through 3 free radicals scavenging tests. PAP exhibited high scavenging effects on OH and DPPH radicals, and both the scavenging rates were about 80%. The scavenging rate of O2^- radical was about 22%.展开更多
BACKGROUND: The fluidity of cell membrane can be affected by various factors. Many experiments have confirmed that the ischemia/reperfusion of organic tissue can increase the contents of free radicals, which lead to h...BACKGROUND: The fluidity of cell membrane can be affected by various factors. Many experiments have confirmed that the ischemia/reperfusion of organic tissue can increase the contents of free radicals, which lead to high rigidity and low fluidity of cell membrane, and the conditions can be changed by Chuanxiongqin. OBJECTIVE: To observe the effect and mechanism of Chuanxiongqin hydrochloride on the fluidity of brain cell membrane in rat models of ischemia/reperfusion. DESIGN: A completely randomized controlled animal trial. SETTINGS: Institute of Brain Sciences; Department of Physiology, Medical College, Datong University. MATERIALS: Twenty male grade Ⅰ Wistar rats of 170-220 g were randomly divided into model group (n =10) and control group (n =10). Chuanxiongqin hydrochloride (molecular mass was 172.2) was purchased from the National Institute for the Control of Pharmaceutical and Biological Products (batch number: 0817-9803); Spin labelers: 5-doxyl-stearlic acid methylester (5DS), 16-doxyl-stearlic acid methylester (16DS), xanthine, xanthine oxidase (XOD) and 5,5-dimeth-1-pyrroline- N-oxide (DMPO) from Sigma Company; Bruker ESP 300 electron paramagnetic resonance (EPR) spectrometer by Bruker Company (Germany). METHODS: The experiments were carried out in the State Key Laboratory of Natural and Biomimetic Drugs, Peking University from June 2001 to July 2002. In the model group, rats were made into models of cerebral ischemia by 30-minute ligation and 2-hour reperfusion of common carotid arteries; The rats in the control group were not made into models. The order parameter (S) and rotational correlation time (τc) were detected with the ESR spectrometer by means of spin labeling. The greater the S and τc, the smaller the fluidity. Meanwhile, the clearance rate of free radicals was detected with ESR spin trapping. The measurement data were compared using the t test. MAIN OUTCOME MEASURES: The S, τc and clearance rates of O2 · and OH· free radicals were compared between the model group and control group. RESULTS: The S and τc in the model group [0.738 4±0.003 5; (8.472±0.027)×10-10 s/circle] were obviously different from those in the control group [0.683 9±0.008 3; (7.945±0.082)×10-10 s/circle, t =5.731, 5.918, P < 0.05], which suggested that ischemia/reperfusion injury decreased the fluidity of brain cell membrane. After adding Chuanxiongqin hydrochloride, there were no obvious differences between the model group [0.688 5±0.030 5; (7.886±0.341)×10-10 s/circle] and control group (P > 0.05), indicating that Chuanxiongqin hydrochloride could recover the fluidity of brain cell membrane after ischemia/reperfusion injury close to the level in the normal control group. Chuanxiongqin hydrochloride could directly scavenge the O2 · and OH· free radicals, and the maximal clearance rates were 83.92% and 44.99% respectively. CONCLUSION: Chuanxiongqin hydrochloride increases the fluidity of membrane of ischemia-injured brain cell by scavenging both O2 ·and OH· free radicals.展开更多
[Objectives]To study the optimum conditions of solid fermentation of natto with antioxidant function as an index.[Methods]Single factor experiment and orthogonal experiment were designed to study the effects of temper...[Objectives]To study the optimum conditions of solid fermentation of natto with antioxidant function as an index.[Methods]Single factor experiment and orthogonal experiment were designed to study the effects of temperature,time,initial pH and inoculum amount on the antioxidant activity of natto solid fermentation.The optimum conditions of natto solid fermentation were determined and the antioxidant ac-tivity of natto extract was compared.[Results]The optimal fermentation conditions were as follows:temperature 32℃,initial pH 7.0,inocu-lation amount 8%,fermentation time 32 h.The hydroxyl radical scavenging rate of natto solid fermentation crude extract was the highest,which was 82.7%.The optimized nato fermentation extract showed stronger scavenging ability for-OH and O,:,and showed obvious dose-effect relationship.ICso was 3.63 and 4.24 mg/mL,respectively,and the scavenging efficiency was 1.3 and 1.9 times higher than that of the unoptimized fermentation extract,respectively.[Conclusions]Natto is rich in nattokinase and other functional factors,and its antioxidant ac-tivity can be improved by optimizing fermentation technology,so that natto products can be widely used,including cosmetic raw materials,nat-to skin care soap,health food and medicine,etc.,and have a broader development prospect.展开更多
In vitro antioxidant activities of resveratrol and piceid against peroxynitrite(ONOO-) were examined by the inhibition of 3-nitrotyrosine formation.Trolox was used as a positive control.Resveratrol and piceid exhibi...In vitro antioxidant activities of resveratrol and piceid against peroxynitrite(ONOO-) were examined by the inhibition of 3-nitrotyrosine formation.Trolox was used as a positive control.Resveratrol and piceid exhibited high ONOO--scavenging activities in a concentration dependent manner.The antioxidant activities(the concentration of test compound required to yield a 50% inhibition of tyrosine nitration,IC 50) of resveratrol and piceid against ONOO-were(48.34±0.97) and(74.69±1.49) μmol/L,respectively.Compared with that of trolox[(105.40±1.16) μmol/L],their scavenging activities were 2.2-and 1.5-fold higher for resveratrol and piceid.Formation of nitroresveratrol as shown by UV-Vis spectroscopy and liquid chromatography-tandom mass spectrometry(LC-MS/MS) analysis indicates that resveratrol could directly scavenge ONOO-via nitration reaction.Our results demonstrate that foods and medicinal herbs with resveratrol and piceid as stronger ONOO-scavengers are valuable ingredients and have healthy application in preventing humans from peroxynitrite-mediated oxidative damage by scavenging peroxynitrite efficiently.展开更多
The flower of Butea monosperma(Lam.)(Fabaceae)has been used in traditional Indian medicine in the treatment of many ailments including liver disorders.To understand the pharmacological basis of its beneficial effects,...The flower of Butea monosperma(Lam.)(Fabaceae)has been used in traditional Indian medicine in the treatment of many ailments including liver disorders.To understand the pharmacological basis of its beneficial effects,the extracts of dried flowers in water,methanol,butanol,ethyl acetate and acetone were evaluated for free radical scavenging and pro-apoptotic activities in cell cultures(human hepatoma Huh-7 cell line and immortalized AML-12 mouse hepatocytes).Butrin and butein-the active constituents of flower extracts-were used as reference molecules.The levels of cell injury markers like lactate dehydrogenase,glutathione and lipid peroxidation and primary antioxidant enzymes glutathione S-transferase and catalase were also measured.The aqueous and butanolic extracts exhibited better 2,2-diphenyl-1-picrylhydrazyl scavenging and cytotoxic activities in hepatoma cells than in immortalized hepatocytes.Interestingly,butein inhibited 2,2-diphenyl-1-picrylhydrazyl radical better than butrin.The aqueous and butanolic extracts were further investigated for hepatoprotection against carbon tertrachloride-induced biochemical changes and cell death.Both extracts,just as butrin and butein,significantly reversed the cellular glutathione levels and lipid peroxidation,and glutathione–S-transferase activity.Lactate dehydrogenase leakage and cell death were also prevented.However,only butein revived the catalase activity.Thus,the butein content of Butea monosperma flower extracts is important for free radical scavenging activity,apoptotic cell death and protection against oxidative injury in hepatic cells.展开更多
Gelatin from the sea cucumber(Paracaudina chinens var.) was hydrolyzed by bromelain and the hydrolysate was found to have a high free radical scavenging activity. The hydrolysate was fractionated through an ultrafiltr...Gelatin from the sea cucumber(Paracaudina chinens var.) was hydrolyzed by bromelain and the hydrolysate was found to have a high free radical scavenging activity. The hydrolysate was fractionated through an ultrafiltration membrane with 5 kDa molecular weight cutoff(MWCO). The portion(less than 5 kDa) was further separated by Sephadex G-25. The active peak was col-lected and assayed for free radical scavenging activity. The scavenging rates for superoxide anion radicals(O2·-) and hydroxyl radi-cals(·OH) of the fraction with the highest activity were 29.02% and 75.41%,respectively. A rabbit liver mitochondrial free radical damage model was adopted to study the free radical scavenging activity of the fraction. The results showed that the sea cucumber gelatin hydrolysate can prevent the damage of rabbit liver and mitochondria.展开更多
We evaluated the hydroxyl and alkyl-oxy radical scavenging activity of instant coffee using an electron spin resonance (ESR) spin-trapping method, which was based the spin-trapping reagent 5-(2,2-dimethy-l,3-propox...We evaluated the hydroxyl and alkyl-oxy radical scavenging activity of instant coffee using an electron spin resonance (ESR) spin-trapping method, which was based the spin-trapping reagent 5-(2,2-dimethy-l,3-propoxycyclophosphoryl)-5-methyl-l-pyrroline N-oxide (CYPMPO). In this method, very pure hydroxyl and alkyl-oxy radicals were generated by illuminating a phosphate buffer solution containing hydrogen peroxide and 2,2'-azobis (2-amidinopropane) dihydrochloride with a Hg-Xe arc lamp. The ESR adduct signal was sensitive and very stable. We concluded that instant coffee has high hydroxyl radical and alkyl-oxy radical scavenging activity.展开更多
The static O-H bond parameters including O-H bond length, O-H charge difference, O-H Mulliken population and O-H bond stretching force constant (k) for 17 phenols were calculated by ab initio method HF/6-31G**. In com...The static O-H bond parameters including O-H bond length, O-H charge difference, O-H Mulliken population and O-H bond stretching force constant (k) for 17 phenols were calculated by ab initio method HF/6-31G**. In combination with the O-H bond dissociation enthalpies (BDE) of the phenols determined by experiment, it was found that there were poor correlationships between the static O-H bond parameters and O-H BDE. Considering the good correlationship bt tween O-H BDE and logarithm of free radical scavenging rate constant for phenolic antioxidant, it is reasonable to believe that the ineffectiveness of static O-H bond parameters in characterizing antioxidant activity arises from the fact that they cannot measure the O-H BDE.展开更多
Four naturally rare 5,6,7-trimethoxy-2,3-cis-dihydroflavonols (3-6) and two 5,6,7-trimethoxy-2,3-trans-dihydroflavonols (7-8) were designed and synthesized. Their antioxidative properties were evaluated by way of ...Four naturally rare 5,6,7-trimethoxy-2,3-cis-dihydroflavonols (3-6) and two 5,6,7-trimethoxy-2,3-trans-dihydroflavonols (7-8) were designed and synthesized. Their antioxidative properties were evaluated by way of examining their scavenging capacities towards DPPH and O2^*- free radicals, as well as by measuring their inhibitory ability against LPO. Both the 2,3-trans and the 2,3- cis conformers exhibited certain quenching abilities to DPPH and O2^*- radicals, while most of the synthetic dihydroflavonols demonstrated remarkable inhibition to LPO.展开更多
The synthesis of (±)-5, 6, 7-trioxygenated dihydroflavonols was carried out. All synthetic compounds were passed through superoxide radical scavenging activity in vitro. Compounds 1 e and 1 g exhibited signific...The synthesis of (±)-5, 6, 7-trioxygenated dihydroflavonols was carried out. All synthetic compounds were passed through superoxide radical scavenging activity in vitro. Compounds 1 e and 1 g exhibited significant bioactivity with the inhibitory rates of 68.1% and 80.9% at 40 μg/mL, respectively.展开更多
Research on marine bioactive peptides has mainly focused on characterization of peptides in hydrolysates prepared with commercial industrial enzymes and the usefulness of such hydrolysates in health and functional foo...Research on marine bioactive peptides has mainly focused on characterization of peptides in hydrolysates prepared with commercial industrial enzymes and the usefulness of such hydrolysates in health and functional foods. However, a relevant question is whether digestion of fish proteins with gastrointestinal proteases per se generates peptides that also can have health promoting properties and can reduce, e.g., diabetes 2, inflammation and hypertension either in relation to gastrointestinal digestion or as alternative to industrial proteases. The aim of the study was to investigate hydrolysates obtained from in vitro sequential digestion of salmon muscle and skin with gastrointestinal proteases including pepsin, pancreatic and pancreatic + mucosal proteases for their ability to scavenge ABTS^+ radicals and inhibit activity of angiotensin I-converting enzyme (ACE) and dipeptidyl peptidase 4 (DPP-4). Furthermore, it was the aim to study the inhibitory mechanism and stability towards ACE and DPP-4 activity. Analysis of〈 10 kDa hydrolysates showed that gastrointestinal proteases generated peptides with clear radical scavenging activity and DPP-4 and ACE inhibiting activity as well. Hydrolysates from pepsin digestion exhibited the lowest ECso values for radical scavenging activity and ACE inhibition, whereas ECso increased in hydrolysates after subsequent digestion with pancreatic and mucosal proteases. Interestingly, ECso values for the DPP-4 inhibition were hardly affected by sequential digestion. Inhibition modes for the muscle hydrolysates were both competitive and non-competitive, but prolonged incubation showed that the inhibitory properties were unstable and therefore they were probably digested as competitive substrates by gastrointestinal proteases.展开更多
Lipid peroxidation inhibition capacity and antiradical activity were evaluated in HPLC fractions of different polarity obtained from two cranberry juices and three extracts isolated from frozen cranberries and pomace ...Lipid peroxidation inhibition capacity and antiradical activity were evaluated in HPLC fractions of different polarity obtained from two cranberry juices and three extracts isolated from frozen cranberries and pomace containing antho-cyanins, water-soluble and apolar phenolic compounds, respectively. Compounds with close polarities were collected to obtain between three and four fractions from each juice or extract. The cranberry phenols are good free radi-cal-scavengers, but they were less efficient at inhibiting the lipid peroxidation. Of all the samples tested, the intermediate polarity fraction of extract rich in apolar phenolic compounds of fruit presented the highest antiradical activity while the most hydrophobic fractions of the anthocyanin-rich extract from fruit and pomace appeared to be the most efficient at inhibiting the lipid peroxidation. The antioxidant or pro-oxidant activity of fractions increased with the con-centration. The phenol polarity and the technological process to manufacture cranberry juice can influence the antioxidant and antiradical activities of fractions.展开更多
The present paper reviews new findings in redoxproperties of the active constituent of Chinese herbalmedicine(CHM),a kind of CHM or a compoundprescription as an antioxidant.Firstly,we have studiedtheir antioxidant and...The present paper reviews new findings in redoxproperties of the active constituent of Chinese herbalmedicine(CHM),a kind of CHM or a compoundprescription as an antioxidant.Firstly,we have studiedtheir antioxidant and prooxidant actions with electronspin resonance(ESR).The results show that the activecomponents from over 10 kinds of CHM are able toscavenge the oxygen free radicals but propyl gallate展开更多
[Objectives]To explore the extraction and in vitro antioxidant effects of astragalus polysaccharides(APS)and Ganoderma lucidum mycelia polysaccharides(GLMPS).[Methods]By studying the polysaccharides of the herbal medi...[Objectives]To explore the extraction and in vitro antioxidant effects of astragalus polysaccharides(APS)and Ganoderma lucidum mycelia polysaccharides(GLMPS).[Methods]By studying the polysaccharides of the herbal medicinal material Astragalus membranaceus and the fungal medicinal material Ganoderma lucidum mycelia,two polysaccharides were mixed according to different proportions and concentrations by using the principle of traditional Chinese medicine compound combination.The effect of polysaccharides on the scavenging ability of hydroxyl radical system was determined by salicylic acid method.[Results]When the compound ratios of GLMPS and APS were 1∶1,1∶4,1∶5,4∶1,and 5∶1,the scavenging effect of compound polysaccharides was better than that of single-component polysaccharides,and with the increase of concentration,the scavenging effect increased.When the ratio of GLMPS and APS was 5∶1,the hydroxyl radical scavenging rate of the compound polysaccharide reached 59.77%,which was 18.72%higher than that of single GLMPS and 28.58%higher than that of single APS.The scavenging effect of compound polysaccharide is closely related to the compound ratio and concentration.[Conclusions]APS and GLMPS can obtain better hydroxyl radical scavenging ability than single-component polysaccharides through compounding in appropriate proportions.In addition,within a suitable concentration range,as the concentration increases,the scavenging ability also increases.展开更多
Objective:To examine the effects of hydroalcoholic extract and fractions of Hordeum vulgare Linn.(H.vulgare,Da Mai)on streptozotocin(STZ)-induced diabetic nephropathy in Sprague-Dawley rat models.Methods:The study inv...Objective:To examine the effects of hydroalcoholic extract and fractions of Hordeum vulgare Linn.(H.vulgare,Da Mai)on streptozotocin(STZ)-induced diabetic nephropathy in Sprague-Dawley rat models.Methods:The study involved preliminary phytochemical screening of extract and fractions,estimation of secondary metabolites,chromatographic studies using high performance liquid chromatography(HPLC),antioxidant potential using 1,1-diphenyl-2-picrylhydrazyl(DPPH),nitric oxide radical scavenging and reducing power methods along with the determination of potential against diabetic nephropathy in STZ-induced rat models.Results:The phytochemical evaluation of the hydroalcoholic extract of H.vulgare and fractions revealed the presence of various phytoconstituents such as alkaloids,saponins,tannins,flavonoids,and glycosides.The chromatographic analysis indicated the peak complementing marker compound epicatechin and significant antioxidant activity in the extract and aqueous fraction.STZ-induced rats showed abnormal levels of serum albumin,creatinine,total cholesterol,blood urea nitrogen(BUN),and triglycerides,and urine albumin and creatinine,which returned to normal after 8 weeks of treatment with hydroalcoholic extract(400 mg/kg)and aqueous fraction(50 mg/kg)of H.vulgare.Conclusion:Hydroalcoholic extract(400 mg/kg)and aqueous fraction(50 mg/kg)of H.vulgare have significant antioxidant potential and positive effects on diabetic nephropathy.The fractionation and optimization increase the concentration of polyphenols in aqueous extract,causing a decrease in the dose required for effects against diabetic nephropathy.展开更多
To study the antioxidant constituents from the stems of Dendrobium nobile, and to discuss theft structure-activity relationship. Compounds were isolated from a 60% ethanolic extract by various chromatographic techniqu...To study the antioxidant constituents from the stems of Dendrobium nobile, and to discuss theft structure-activity relationship. Compounds were isolated from a 60% ethanolic extract by various chromatographic techniques and were identified by spectral analysis. The antioxidant activities of compounds were evaluated by DPPH free radical scavenging assay. Five phenanthrenes and four lignans were obtained from the active fractions ofD. nobile. Their structures were identified as fimbriatone (1), confusarin (2), flavanthrinin (3), 2,5-dihydroxy-4,9-dimethoxyphenanthrene (4), 3,7-dihydroxy-2,4-dimethoxyphenanthrene (5), syringaresinol (6), pinoresinol (7), medioresinol (8) and lirioresinol-A (9), respectively. Compounds 2 and 6 exhibited more potent DPPH scavenging activities than vitamin C. All the above compounds were reported from this plant for the first time, and compounds 3, 4 and 9 were reported for the first time from the genus of Dendrobiurn. For all phenanthrenes and lignans, an electron-donating methoxyl group in the ortho position to the phenolic hydroxyl group exhibits enhanced antioxidant activities.展开更多
Objective:To identify the hepatoprotective and in vitro antioxidant activity of Lumnitzera racemosa(L.racemosa) leaf extract.Methods:Animals in Group 1 served as vehicle control. Group 2 served as hepatotoxin(CCL_4 tr...Objective:To identify the hepatoprotective and in vitro antioxidant activity of Lumnitzera racemosa(L.racemosa) leaf extract.Methods:Animals in Group 1 served as vehicle control. Group 2 served as hepatotoxin(CCL_4 treated) group.Group 3 served as positive control(Silyntarin) group,and Group 4.S and ft served as(73,150 and 300 nig/kg bw p.o.)L.racemosa leaf extract treated groups.Moreover,in vitro antioxidant DPPH,hydroxyl radical scavenging activity(HRSA),NO,ferric reducing antioxidant power(FRAP),lipid hydroperoxide(LPO) and super oxide dismutase(SOD) were also analyzed for the leaf extract.Results:The levels of the serum parameters such as serum glutamic oxaloacetic transaminase(SGOT).serum glutamic pyruvic transaminase(SGPT).alkaline phosphatase(ALP),bilirubin,cholesterol(CHL).sugar and lactate dehydrogenase(LDH) were significantly increased in COL_4 treated rats when compared with the control group(P<0.05).But the L.racemosa leaf extract treated rats showed maximum reduction of SGOT[(210.16±19.63)IU/L].SGPT[(82.37±13.87) IU/L].ALP[(197.63±23.4.3)IU/L],bilurubilt[(2.13 ±0.84) mg/dL].cholesterol[(163.83± 13.63) mg/dL].sugar[(93.00±7.63) mg/dL]and LDH[(1134.00) ±285.00)IU/L]were observed with the high dose(300 mg/kg bw) of leaf extract treated rats. Histopathological scores showed that,no visible changes were observed with high dose(300 mg/ kgbw) of leaf extract treated rats except few mild necrosis.The IC_(50) values were observed as(56.37 ±4.87)μg/mL,(57.68±1.98) μg/mL,(64.15±2.90)μg/mL,(61.94±3.98)μg/mL,(94.53± 1.68) μg/mL and(69.7±2.65)μg/mL for DPPH,HRSA,NO,FRAP,LPO and SOL) radical scavenging activities, respectively.Conclusions:In conclusion,the hepatoprotective effect of the L.racemosa leaf extract might be due to the presence of phenolic groups,terpenoids and alkaloids and in vitro antioxidant properties.展开更多
The anthocyanin pigment extracted from green-wheat-bran was studied to identify its antioxidant activity.The antioxidant activities of the pigment were evaluated by anti-lipid peroxidation,total antioxidant activity ...The anthocyanin pigment extracted from green-wheat-bran was studied to identify its antioxidant activity.The antioxidant activities of the pigment were evaluated by anti-lipid peroxidation,total antioxidant activity (TAA),superoxide anion radical scavenging activity (SARSA),active oxygen scavenging activity (AOSA),and DPPH (1,1-diphenyl-2 picrylhydrazyl free radical) radical scavenging activity.The results showed that the pigment had higher antioxidant activity and TAA,SARSA,AOSA and DPPH.scavenging activities at a certain concentration than Vc (antiscorbutic vitamin,vitamin C),and the capacity increased with the increase of pigment concentration.Its TAA was 51.06 U mL-1,1.73 times of Vc,and SARSA 18 025.21 U mL-1,2.26% higher than Vc,and AOSA 3 776.31 U mL-1,1.24 times of Vc.As to the DPPH.scavenging activity of the pigment,there was a trend that higher concentration performed higher activity significantly improved with the company of Vc.The pigment showed significant antioxidant activities evaluated by different assays.Results will provide a better understanding on antioxidant activity of green wheat and allow the screening or breeding of green wheat varieties with higher antioxidant activity for food processing.展开更多
基金Scientific Research Program of Beijing Municipal Commission of Education (KM200710011007)~~
文摘[ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging substances from sweet potato leaves were optimized by orthogonal test and the bioactive components in extracts were investigated by correlation analysis. [ Result] Sweet potato leaves contain the bioactive substances scavenging DPPH free radical and hydroxyl free radical. Extracting solvent species is the most important factor that influencing extraction yield. The optimal extraction and storage conditions are as following: water as solvent, pH 8.0 of extracting liquid, storage at 25 ℃. There is a good positive linear relationship between the content of total phenols in sweet potato leaves and corresponding scavenging rates against both the DPPH free radical and hydroxyl free radical. For the content of total flavones in sweet potato leaves, just a correlation with scavenging rate against hydroxyl free radical shown in test. [ Conclusion] The phenols in ex- tracts could effectively scavenge both the DPPH free radical and hydroxyl free radical, whereas the flavones in extracts can only function on the hydroxyl free radical.
基金Supported by the Science and Technique Foundation of Jilin Province, China(No20020503-2)
文摘A crude polysaccharide was extracted from Physalis alkekengi L. fruit. HPLC was used for the component analysis of the polysaccharide. The results indicate that Physalis alkekengi L. polysaccharide(PAP) was composed of rhamnose, xylose, arabinose, galactose, and glucose. Free radicals scavenging activity of PAP was studied through 3 free radicals scavenging tests. PAP exhibited high scavenging effects on OH and DPPH radicals, and both the scavenging rates were about 80%. The scavenging rate of O2^- radical was about 22%.
文摘BACKGROUND: The fluidity of cell membrane can be affected by various factors. Many experiments have confirmed that the ischemia/reperfusion of organic tissue can increase the contents of free radicals, which lead to high rigidity and low fluidity of cell membrane, and the conditions can be changed by Chuanxiongqin. OBJECTIVE: To observe the effect and mechanism of Chuanxiongqin hydrochloride on the fluidity of brain cell membrane in rat models of ischemia/reperfusion. DESIGN: A completely randomized controlled animal trial. SETTINGS: Institute of Brain Sciences; Department of Physiology, Medical College, Datong University. MATERIALS: Twenty male grade Ⅰ Wistar rats of 170-220 g were randomly divided into model group (n =10) and control group (n =10). Chuanxiongqin hydrochloride (molecular mass was 172.2) was purchased from the National Institute for the Control of Pharmaceutical and Biological Products (batch number: 0817-9803); Spin labelers: 5-doxyl-stearlic acid methylester (5DS), 16-doxyl-stearlic acid methylester (16DS), xanthine, xanthine oxidase (XOD) and 5,5-dimeth-1-pyrroline- N-oxide (DMPO) from Sigma Company; Bruker ESP 300 electron paramagnetic resonance (EPR) spectrometer by Bruker Company (Germany). METHODS: The experiments were carried out in the State Key Laboratory of Natural and Biomimetic Drugs, Peking University from June 2001 to July 2002. In the model group, rats were made into models of cerebral ischemia by 30-minute ligation and 2-hour reperfusion of common carotid arteries; The rats in the control group were not made into models. The order parameter (S) and rotational correlation time (τc) were detected with the ESR spectrometer by means of spin labeling. The greater the S and τc, the smaller the fluidity. Meanwhile, the clearance rate of free radicals was detected with ESR spin trapping. The measurement data were compared using the t test. MAIN OUTCOME MEASURES: The S, τc and clearance rates of O2 · and OH· free radicals were compared between the model group and control group. RESULTS: The S and τc in the model group [0.738 4±0.003 5; (8.472±0.027)×10-10 s/circle] were obviously different from those in the control group [0.683 9±0.008 3; (7.945±0.082)×10-10 s/circle, t =5.731, 5.918, P < 0.05], which suggested that ischemia/reperfusion injury decreased the fluidity of brain cell membrane. After adding Chuanxiongqin hydrochloride, there were no obvious differences between the model group [0.688 5±0.030 5; (7.886±0.341)×10-10 s/circle] and control group (P > 0.05), indicating that Chuanxiongqin hydrochloride could recover the fluidity of brain cell membrane after ischemia/reperfusion injury close to the level in the normal control group. Chuanxiongqin hydrochloride could directly scavenge the O2 · and OH· free radicals, and the maximal clearance rates were 83.92% and 44.99% respectively. CONCLUSION: Chuanxiongqin hydrochloride increases the fluidity of membrane of ischemia-injured brain cell by scavenging both O2 ·and OH· free radicals.
基金Supported by 2023 Zhanjiang Non-funded Science and Technology Research Plan(2023B01023)2022 University-level Education and Teaching Reform Project of Lingnan Normal University(LingShiJiaoWu2022154).Junxia SONG,bachelor degree,experimenter,research fields:physical geography.
文摘[Objectives]To study the optimum conditions of solid fermentation of natto with antioxidant function as an index.[Methods]Single factor experiment and orthogonal experiment were designed to study the effects of temperature,time,initial pH and inoculum amount on the antioxidant activity of natto solid fermentation.The optimum conditions of natto solid fermentation were determined and the antioxidant ac-tivity of natto extract was compared.[Results]The optimal fermentation conditions were as follows:temperature 32℃,initial pH 7.0,inocu-lation amount 8%,fermentation time 32 h.The hydroxyl radical scavenging rate of natto solid fermentation crude extract was the highest,which was 82.7%.The optimized nato fermentation extract showed stronger scavenging ability for-OH and O,:,and showed obvious dose-effect relationship.ICso was 3.63 and 4.24 mg/mL,respectively,and the scavenging efficiency was 1.3 and 1.9 times higher than that of the unoptimized fermentation extract,respectively.[Conclusions]Natto is rich in nattokinase and other functional factors,and its antioxidant ac-tivity can be improved by optimizing fermentation technology,so that natto products can be widely used,including cosmetic raw materials,nat-to skin care soap,health food and medicine,etc.,and have a broader development prospect.
基金Supported by the National Basic Research Program of China(Nos.2012CB721105,2011CBA00802,2007CB714301)the National Natural Science Foundation of China(No.30873400)the Specialized Research Fund for the Doctoral Program of Higher Education of China(No.20090032110015)
文摘In vitro antioxidant activities of resveratrol and piceid against peroxynitrite(ONOO-) were examined by the inhibition of 3-nitrotyrosine formation.Trolox was used as a positive control.Resveratrol and piceid exhibited high ONOO--scavenging activities in a concentration dependent manner.The antioxidant activities(the concentration of test compound required to yield a 50% inhibition of tyrosine nitration,IC 50) of resveratrol and piceid against ONOO-were(48.34±0.97) and(74.69±1.49) μmol/L,respectively.Compared with that of trolox[(105.40±1.16) μmol/L],their scavenging activities were 2.2-and 1.5-fold higher for resveratrol and piceid.Formation of nitroresveratrol as shown by UV-Vis spectroscopy and liquid chromatography-tandom mass spectrometry(LC-MS/MS) analysis indicates that resveratrol could directly scavenge ONOO-via nitration reaction.Our results demonstrate that foods and medicinal herbs with resveratrol and piceid as stronger ONOO-scavengers are valuable ingredients and have healthy application in preventing humans from peroxynitrite-mediated oxidative damage by scavenging peroxynitrite efficiently.
基金supported by grant no.90(0039)/04/EMR-II of Council of Scientific and Industrial Research,Government of India,New Delhi.Anuradha Sehrawat has been a Research Associate of Department of Biotechnology,Government of India,during the period of this study。
文摘The flower of Butea monosperma(Lam.)(Fabaceae)has been used in traditional Indian medicine in the treatment of many ailments including liver disorders.To understand the pharmacological basis of its beneficial effects,the extracts of dried flowers in water,methanol,butanol,ethyl acetate and acetone were evaluated for free radical scavenging and pro-apoptotic activities in cell cultures(human hepatoma Huh-7 cell line and immortalized AML-12 mouse hepatocytes).Butrin and butein-the active constituents of flower extracts-were used as reference molecules.The levels of cell injury markers like lactate dehydrogenase,glutathione and lipid peroxidation and primary antioxidant enzymes glutathione S-transferase and catalase were also measured.The aqueous and butanolic extracts exhibited better 2,2-diphenyl-1-picrylhydrazyl scavenging and cytotoxic activities in hepatoma cells than in immortalized hepatocytes.Interestingly,butein inhibited 2,2-diphenyl-1-picrylhydrazyl radical better than butrin.The aqueous and butanolic extracts were further investigated for hepatoprotection against carbon tertrachloride-induced biochemical changes and cell death.Both extracts,just as butrin and butein,significantly reversed the cellular glutathione levels and lipid peroxidation,and glutathione–S-transferase activity.Lactate dehydrogenase leakage and cell death were also prevented.However,only butein revived the catalase activity.Thus,the butein content of Butea monosperma flower extracts is important for free radical scavenging activity,apoptotic cell death and protection against oxidative injury in hepatic cells.
文摘Gelatin from the sea cucumber(Paracaudina chinens var.) was hydrolyzed by bromelain and the hydrolysate was found to have a high free radical scavenging activity. The hydrolysate was fractionated through an ultrafiltration membrane with 5 kDa molecular weight cutoff(MWCO). The portion(less than 5 kDa) was further separated by Sephadex G-25. The active peak was col-lected and assayed for free radical scavenging activity. The scavenging rates for superoxide anion radicals(O2·-) and hydroxyl radi-cals(·OH) of the fraction with the highest activity were 29.02% and 75.41%,respectively. A rabbit liver mitochondrial free radical damage model was adopted to study the free radical scavenging activity of the fraction. The results showed that the sea cucumber gelatin hydrolysate can prevent the damage of rabbit liver and mitochondria.
文摘We evaluated the hydroxyl and alkyl-oxy radical scavenging activity of instant coffee using an electron spin resonance (ESR) spin-trapping method, which was based the spin-trapping reagent 5-(2,2-dimethy-l,3-propoxycyclophosphoryl)-5-methyl-l-pyrroline N-oxide (CYPMPO). In this method, very pure hydroxyl and alkyl-oxy radicals were generated by illuminating a phosphate buffer solution containing hydrogen peroxide and 2,2'-azobis (2-amidinopropane) dihydrochloride with a Hg-Xe arc lamp. The ESR adduct signal was sensitive and very stable. We concluded that instant coffee has high hydroxyl radical and alkyl-oxy radical scavenging activity.
文摘The static O-H bond parameters including O-H bond length, O-H charge difference, O-H Mulliken population and O-H bond stretching force constant (k) for 17 phenols were calculated by ab initio method HF/6-31G**. In combination with the O-H bond dissociation enthalpies (BDE) of the phenols determined by experiment, it was found that there were poor correlationships between the static O-H bond parameters and O-H BDE. Considering the good correlationship bt tween O-H BDE and logarithm of free radical scavenging rate constant for phenolic antioxidant, it is reasonable to believe that the ineffectiveness of static O-H bond parameters in characterizing antioxidant activity arises from the fact that they cannot measure the O-H BDE.
基金supported by Intramural Foundation from Wenzhou Medical College
文摘Four naturally rare 5,6,7-trimethoxy-2,3-cis-dihydroflavonols (3-6) and two 5,6,7-trimethoxy-2,3-trans-dihydroflavonols (7-8) were designed and synthesized. Their antioxidative properties were evaluated by way of examining their scavenging capacities towards DPPH and O2^*- free radicals, as well as by measuring their inhibitory ability against LPO. Both the 2,3-trans and the 2,3- cis conformers exhibited certain quenching abilities to DPPH and O2^*- radicals, while most of the synthetic dihydroflavonols demonstrated remarkable inhibition to LPO.
文摘The synthesis of (±)-5, 6, 7-trioxygenated dihydroflavonols was carried out. All synthetic compounds were passed through superoxide radical scavenging activity in vitro. Compounds 1 e and 1 g exhibited significant bioactivity with the inhibitory rates of 68.1% and 80.9% at 40 μg/mL, respectively.
文摘Research on marine bioactive peptides has mainly focused on characterization of peptides in hydrolysates prepared with commercial industrial enzymes and the usefulness of such hydrolysates in health and functional foods. However, a relevant question is whether digestion of fish proteins with gastrointestinal proteases per se generates peptides that also can have health promoting properties and can reduce, e.g., diabetes 2, inflammation and hypertension either in relation to gastrointestinal digestion or as alternative to industrial proteases. The aim of the study was to investigate hydrolysates obtained from in vitro sequential digestion of salmon muscle and skin with gastrointestinal proteases including pepsin, pancreatic and pancreatic + mucosal proteases for their ability to scavenge ABTS^+ radicals and inhibit activity of angiotensin I-converting enzyme (ACE) and dipeptidyl peptidase 4 (DPP-4). Furthermore, it was the aim to study the inhibitory mechanism and stability towards ACE and DPP-4 activity. Analysis of〈 10 kDa hydrolysates showed that gastrointestinal proteases generated peptides with clear radical scavenging activity and DPP-4 and ACE inhibiting activity as well. Hydrolysates from pepsin digestion exhibited the lowest ECso values for radical scavenging activity and ACE inhibition, whereas ECso increased in hydrolysates after subsequent digestion with pancreatic and mucosal proteases. Interestingly, ECso values for the DPP-4 inhibition were hardly affected by sequential digestion. Inhibition modes for the muscle hydrolysates were both competitive and non-competitive, but prolonged incubation showed that the inhibitory properties were unstable and therefore they were probably digested as competitive substrates by gastrointestinal proteases.
基金This research was supported by the Natural Sciences and Engineering Research Council of Canada(NSERC) by Atoka Cranberries Inc.(Manseau,QC,Canada).
文摘Lipid peroxidation inhibition capacity and antiradical activity were evaluated in HPLC fractions of different polarity obtained from two cranberry juices and three extracts isolated from frozen cranberries and pomace containing antho-cyanins, water-soluble and apolar phenolic compounds, respectively. Compounds with close polarities were collected to obtain between three and four fractions from each juice or extract. The cranberry phenols are good free radi-cal-scavengers, but they were less efficient at inhibiting the lipid peroxidation. Of all the samples tested, the intermediate polarity fraction of extract rich in apolar phenolic compounds of fruit presented the highest antiradical activity while the most hydrophobic fractions of the anthocyanin-rich extract from fruit and pomace appeared to be the most efficient at inhibiting the lipid peroxidation. The antioxidant or pro-oxidant activity of fractions increased with the con-centration. The phenol polarity and the technological process to manufacture cranberry juice can influence the antioxidant and antiradical activities of fractions.
文摘The present paper reviews new findings in redoxproperties of the active constituent of Chinese herbalmedicine(CHM),a kind of CHM or a compoundprescription as an antioxidant.Firstly,we have studiedtheir antioxidant and prooxidant actions with electronspin resonance(ESR).The results show that the activecomponents from over 10 kinds of CHM are able toscavenge the oxygen free radicals but propyl gallate
基金Supported by the Project of"Striving to Be First-classImproving Weak LinksBuilding Strong Feature"in 2019–Tropical and South China Sea Biological Resources Comprehensive Utilization Program(000301900410)。
文摘[Objectives]To explore the extraction and in vitro antioxidant effects of astragalus polysaccharides(APS)and Ganoderma lucidum mycelia polysaccharides(GLMPS).[Methods]By studying the polysaccharides of the herbal medicinal material Astragalus membranaceus and the fungal medicinal material Ganoderma lucidum mycelia,two polysaccharides were mixed according to different proportions and concentrations by using the principle of traditional Chinese medicine compound combination.The effect of polysaccharides on the scavenging ability of hydroxyl radical system was determined by salicylic acid method.[Results]When the compound ratios of GLMPS and APS were 1∶1,1∶4,1∶5,4∶1,and 5∶1,the scavenging effect of compound polysaccharides was better than that of single-component polysaccharides,and with the increase of concentration,the scavenging effect increased.When the ratio of GLMPS and APS was 5∶1,the hydroxyl radical scavenging rate of the compound polysaccharide reached 59.77%,which was 18.72%higher than that of single GLMPS and 28.58%higher than that of single APS.The scavenging effect of compound polysaccharide is closely related to the compound ratio and concentration.[Conclusions]APS and GLMPS can obtain better hydroxyl radical scavenging ability than single-component polysaccharides through compounding in appropriate proportions.In addition,within a suitable concentration range,as the concentration increases,the scavenging ability also increases.
基金supported by Rashtrsant Tukadoji Maharaj Memorial Fellowship from Rashtrasant Tukadoji Maharaj Nagpur University。
文摘Objective:To examine the effects of hydroalcoholic extract and fractions of Hordeum vulgare Linn.(H.vulgare,Da Mai)on streptozotocin(STZ)-induced diabetic nephropathy in Sprague-Dawley rat models.Methods:The study involved preliminary phytochemical screening of extract and fractions,estimation of secondary metabolites,chromatographic studies using high performance liquid chromatography(HPLC),antioxidant potential using 1,1-diphenyl-2-picrylhydrazyl(DPPH),nitric oxide radical scavenging and reducing power methods along with the determination of potential against diabetic nephropathy in STZ-induced rat models.Results:The phytochemical evaluation of the hydroalcoholic extract of H.vulgare and fractions revealed the presence of various phytoconstituents such as alkaloids,saponins,tannins,flavonoids,and glycosides.The chromatographic analysis indicated the peak complementing marker compound epicatechin and significant antioxidant activity in the extract and aqueous fraction.STZ-induced rats showed abnormal levels of serum albumin,creatinine,total cholesterol,blood urea nitrogen(BUN),and triglycerides,and urine albumin and creatinine,which returned to normal after 8 weeks of treatment with hydroalcoholic extract(400 mg/kg)and aqueous fraction(50 mg/kg)of H.vulgare.Conclusion:Hydroalcoholic extract(400 mg/kg)and aqueous fraction(50 mg/kg)of H.vulgare have significant antioxidant potential and positive effects on diabetic nephropathy.The fractionation and optimization increase the concentration of polyphenols in aqueous extract,causing a decrease in the dose required for effects against diabetic nephropathy.
文摘To study the antioxidant constituents from the stems of Dendrobium nobile, and to discuss theft structure-activity relationship. Compounds were isolated from a 60% ethanolic extract by various chromatographic techniques and were identified by spectral analysis. The antioxidant activities of compounds were evaluated by DPPH free radical scavenging assay. Five phenanthrenes and four lignans were obtained from the active fractions ofD. nobile. Their structures were identified as fimbriatone (1), confusarin (2), flavanthrinin (3), 2,5-dihydroxy-4,9-dimethoxyphenanthrene (4), 3,7-dihydroxy-2,4-dimethoxyphenanthrene (5), syringaresinol (6), pinoresinol (7), medioresinol (8) and lirioresinol-A (9), respectively. Compounds 2 and 6 exhibited more potent DPPH scavenging activities than vitamin C. All the above compounds were reported from this plant for the first time, and compounds 3, 4 and 9 were reported for the first time from the genus of Dendrobiurn. For all phenanthrenes and lignans, an electron-donating methoxyl group in the ortho position to the phenolic hydroxyl group exhibits enhanced antioxidant activities.
文摘Objective:To identify the hepatoprotective and in vitro antioxidant activity of Lumnitzera racemosa(L.racemosa) leaf extract.Methods:Animals in Group 1 served as vehicle control. Group 2 served as hepatotoxin(CCL_4 treated) group.Group 3 served as positive control(Silyntarin) group,and Group 4.S and ft served as(73,150 and 300 nig/kg bw p.o.)L.racemosa leaf extract treated groups.Moreover,in vitro antioxidant DPPH,hydroxyl radical scavenging activity(HRSA),NO,ferric reducing antioxidant power(FRAP),lipid hydroperoxide(LPO) and super oxide dismutase(SOD) were also analyzed for the leaf extract.Results:The levels of the serum parameters such as serum glutamic oxaloacetic transaminase(SGOT).serum glutamic pyruvic transaminase(SGPT).alkaline phosphatase(ALP),bilirubin,cholesterol(CHL).sugar and lactate dehydrogenase(LDH) were significantly increased in COL_4 treated rats when compared with the control group(P<0.05).But the L.racemosa leaf extract treated rats showed maximum reduction of SGOT[(210.16±19.63)IU/L].SGPT[(82.37±13.87) IU/L].ALP[(197.63±23.4.3)IU/L],bilurubilt[(2.13 ±0.84) mg/dL].cholesterol[(163.83± 13.63) mg/dL].sugar[(93.00±7.63) mg/dL]and LDH[(1134.00) ±285.00)IU/L]were observed with the high dose(300 mg/kg bw) of leaf extract treated rats. Histopathological scores showed that,no visible changes were observed with high dose(300 mg/ kgbw) of leaf extract treated rats except few mild necrosis.The IC_(50) values were observed as(56.37 ±4.87)μg/mL,(57.68±1.98) μg/mL,(64.15±2.90)μg/mL,(61.94±3.98)μg/mL,(94.53± 1.68) μg/mL and(69.7±2.65)μg/mL for DPPH,HRSA,NO,FRAP,LPO and SOL) radical scavenging activities, respectively.Conclusions:In conclusion,the hepatoprotective effect of the L.racemosa leaf extract might be due to the presence of phenolic groups,terpenoids and alkaloids and in vitro antioxidant properties.
基金supported by the National Technologies R&D Program of China (2006BAD01A02)the Excellent Medium-Youth Scientist Scientific Research Reward Fundation of Shandong Province, China (BS2009NY036)the Youth Science and Technology Creative Fundation Item of Shandong Agricultural University, China
文摘The anthocyanin pigment extracted from green-wheat-bran was studied to identify its antioxidant activity.The antioxidant activities of the pigment were evaluated by anti-lipid peroxidation,total antioxidant activity (TAA),superoxide anion radical scavenging activity (SARSA),active oxygen scavenging activity (AOSA),and DPPH (1,1-diphenyl-2 picrylhydrazyl free radical) radical scavenging activity.The results showed that the pigment had higher antioxidant activity and TAA,SARSA,AOSA and DPPH.scavenging activities at a certain concentration than Vc (antiscorbutic vitamin,vitamin C),and the capacity increased with the increase of pigment concentration.Its TAA was 51.06 U mL-1,1.73 times of Vc,and SARSA 18 025.21 U mL-1,2.26% higher than Vc,and AOSA 3 776.31 U mL-1,1.24 times of Vc.As to the DPPH.scavenging activity of the pigment,there was a trend that higher concentration performed higher activity significantly improved with the company of Vc.The pigment showed significant antioxidant activities evaluated by different assays.Results will provide a better understanding on antioxidant activity of green wheat and allow the screening or breeding of green wheat varieties with higher antioxidant activity for food processing.