Fish skin collagen hydrolysates(FSCH) were prepared from walleye pollock(Theragra chalcogramma) using a mixture of enzymes,namely trypsin and flavourzyme. The degree of hydrolysis of the skin collagen was 27.3%. FSCH ...Fish skin collagen hydrolysates(FSCH) were prepared from walleye pollock(Theragra chalcogramma) using a mixture of enzymes,namely trypsin and flavourzyme. The degree of hydrolysis of the skin collagen was 27.3%. FSCH was mainly composed of low-molecular-weight peptides and the relative proportion of <1 000Da fraction was 70.6%. Free radical and oxygen species scavenging activities of FSCH were investigated in four model systems,including diphenylpicrylhy-drazyl radical(DPPH),superoxide anion radical,hydroxyl radical and hydrogen peroxide model,and compared with that of a native antioxidant,reduced glutathione(GSH). FSCH was also evaluated by water-absorbing and water-holding capacity. The results showed that FSCH was able to scavenge free radical and oxygen species significantly and to enhance water-absorbing and water-holding capacity remarkably. Therefore,FSCH may have potential applications in the medicine and food industries.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
Objective:The activity of enzymes participating in the systems of antioxidant protection was assayed in the peel and pulp of sunflower.The essential roles of proteases in food stimulate research to find other sources ...Objective:The activity of enzymes participating in the systems of antioxidant protection was assayed in the peel and pulp of sunflower.The essential roles of proteases in food stimulate research to find other sources of the enzyme especially from non-conventional sources.In the present work,we study several biochemical parameters in the pulp and peel of sunflower.Methods:Pulp and peel of sunflower was extracted,antioxidant enzymes and nonenzymatic antioxidant were measured.Alkaline protease was measured and purified from pulp in sunflower.Results:High carbohydrate concentration,beta-carotene,catalase and ascorbate peroxidase activities,free radical scavenging capacity and free flavonoid content were observed in the peel of sunflower.Whereas,MDA and ceruloplasmin activities were high in the pulp of sunflower.Conclusions:The present study concluded that peel in sunflower are strong radical scavengers and can be considered as good sources of natural antioxidants for medicinal and commercial uses.Further analysis showed that protease activity was a significantly high in the pulp compared to the peel.展开更多
Five Libyan medicinal plants Thapsia garganica, Hammada scoparia, Euphorbia serrata, Hyoscyamus albus and Retama rateam were selected to evaluate their biological activities. Their total phenolic and flavanoid content...Five Libyan medicinal plants Thapsia garganica, Hammada scoparia, Euphorbia serrata, Hyoscyamus albus and Retama rateam were selected to evaluate their biological activities. Their total phenolic and flavanoid contents were assessed. The antioxidant activity was estimated using 2, 2-di- phenyl-1-picrylhydrazyl (DPPH) as free radical scavenger. Their crude extracts showed reducing potential proportional to their concentration. The correlation coefficient (R2) between antioxidant activity and their total phenolics and flavanoids content is 0.77 and 0.98 respectively. Crude aqueous, methanolic as well as alkaloids extracts of the five plants were tested against a number of G+ve and G-ve sensitive resistant (e.g MRSA) bacteria beside some fungal species. The aqueous extracts displayed weak antibacterial activity whereas methanolic extracts were profoundly effective against both G+ve and G-ve bacteria. The extracts of E. serrata and H. scoparia were highly effective against E. coli in particular. The alkaloid-rich extracts of H. albus and H. scoparia induced remarkable bacteriostatic and fungistatic effects. The bioactive ingredients of H. scoparia, E. serrata and R. rateam extracts are shown to be potential sources of natural antioxidant and antimicrobial ingredients favoring their possible use in industrial pharmacology on large scale.展开更多
OBJECTIVE: To evaluate the antioxidant capacity of the extract from Jiangtang Xiaozhi recipe(JXR) of in vitro.METHODS: JXR extract was prepared according to previously reported method. In vitro antioxidant assays were...OBJECTIVE: To evaluate the antioxidant capacity of the extract from Jiangtang Xiaozhi recipe(JXR) of in vitro.METHODS: JXR extract was prepared according to previously reported method. In vitro antioxidant assays were used in this experiment, including 1,1-Diphenyl-2-picrylhydrazyl free radical(DPPH) radical scavenging ability, 2-2’-Azinobis-(3-ethylbenzthiazoline-6-sul phonate(ABTS) radical scavenging ability, reducing power assay, fluorescence recovery after photo bleaching assay, β-carotene bleaching assay, ferric thiocyanate assay, and thiobarbituric acid method.RESULTS: DPPH, ABTS assay showed that JXR extract had distinct effect on scavenging free radicals;reducing power and ferricreducing-antioxidant power assay showed that JXR extract possessed redox ability;β-Carotene bleaching assay and antioxidant activity in a linoleic acid system using ferric thiocyanate method, thiobarbituric acid assay indicated that JXR extract could effectively inhibit lipid peroxidation, and the effect was better than that of Vitamin C.CONCLUSION: JXR extract has significant antioxidant capacity in vitro.展开更多
基金supported by the High Technology Research and Development Program of China (No. 2006AA09Z438)the National Natural Science Foundation of China (No. 30871943).
文摘Fish skin collagen hydrolysates(FSCH) were prepared from walleye pollock(Theragra chalcogramma) using a mixture of enzymes,namely trypsin and flavourzyme. The degree of hydrolysis of the skin collagen was 27.3%. FSCH was mainly composed of low-molecular-weight peptides and the relative proportion of <1 000Da fraction was 70.6%. Free radical and oxygen species scavenging activities of FSCH were investigated in four model systems,including diphenylpicrylhy-drazyl radical(DPPH),superoxide anion radical,hydroxyl radical and hydrogen peroxide model,and compared with that of a native antioxidant,reduced glutathione(GSH). FSCH was also evaluated by water-absorbing and water-holding capacity. The results showed that FSCH was able to scavenge free radical and oxygen species significantly and to enhance water-absorbing and water-holding capacity remarkably. Therefore,FSCH may have potential applications in the medicine and food industries.
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Objective:The activity of enzymes participating in the systems of antioxidant protection was assayed in the peel and pulp of sunflower.The essential roles of proteases in food stimulate research to find other sources of the enzyme especially from non-conventional sources.In the present work,we study several biochemical parameters in the pulp and peel of sunflower.Methods:Pulp and peel of sunflower was extracted,antioxidant enzymes and nonenzymatic antioxidant were measured.Alkaline protease was measured and purified from pulp in sunflower.Results:High carbohydrate concentration,beta-carotene,catalase and ascorbate peroxidase activities,free radical scavenging capacity and free flavonoid content were observed in the peel of sunflower.Whereas,MDA and ceruloplasmin activities were high in the pulp of sunflower.Conclusions:The present study concluded that peel in sunflower are strong radical scavengers and can be considered as good sources of natural antioxidants for medicinal and commercial uses.Further analysis showed that protease activity was a significantly high in the pulp compared to the peel.
文摘Five Libyan medicinal plants Thapsia garganica, Hammada scoparia, Euphorbia serrata, Hyoscyamus albus and Retama rateam were selected to evaluate their biological activities. Their total phenolic and flavanoid contents were assessed. The antioxidant activity was estimated using 2, 2-di- phenyl-1-picrylhydrazyl (DPPH) as free radical scavenger. Their crude extracts showed reducing potential proportional to their concentration. The correlation coefficient (R2) between antioxidant activity and their total phenolics and flavanoids content is 0.77 and 0.98 respectively. Crude aqueous, methanolic as well as alkaloids extracts of the five plants were tested against a number of G+ve and G-ve sensitive resistant (e.g MRSA) bacteria beside some fungal species. The aqueous extracts displayed weak antibacterial activity whereas methanolic extracts were profoundly effective against both G+ve and G-ve bacteria. The extracts of E. serrata and H. scoparia were highly effective against E. coli in particular. The alkaloid-rich extracts of H. albus and H. scoparia induced remarkable bacteriostatic and fungistatic effects. The bioactive ingredients of H. scoparia, E. serrata and R. rateam extracts are shown to be potential sources of natural antioxidant and antimicrobial ingredients favoring their possible use in industrial pharmacology on large scale.
基金Supported by The Special Project for Academic Construction of Peking Union Medical CollegeBeijing(Traditional Chinese Medicine Cultural Construction for Heritage in Chinese Union of Medicinal Plant Gardens,Tsinghua,211-201920100902)Beijing Natural Science Foundation(The molecular mechanism of the retinal pericyte protection by Jangtang Xiaozhi Tablets in STZ induced diabetic rats,No.7152100)。
文摘OBJECTIVE: To evaluate the antioxidant capacity of the extract from Jiangtang Xiaozhi recipe(JXR) of in vitro.METHODS: JXR extract was prepared according to previously reported method. In vitro antioxidant assays were used in this experiment, including 1,1-Diphenyl-2-picrylhydrazyl free radical(DPPH) radical scavenging ability, 2-2’-Azinobis-(3-ethylbenzthiazoline-6-sul phonate(ABTS) radical scavenging ability, reducing power assay, fluorescence recovery after photo bleaching assay, β-carotene bleaching assay, ferric thiocyanate assay, and thiobarbituric acid method.RESULTS: DPPH, ABTS assay showed that JXR extract had distinct effect on scavenging free radicals;reducing power and ferricreducing-antioxidant power assay showed that JXR extract possessed redox ability;β-Carotene bleaching assay and antioxidant activity in a linoleic acid system using ferric thiocyanate method, thiobarbituric acid assay indicated that JXR extract could effectively inhibit lipid peroxidation, and the effect was better than that of Vitamin C.CONCLUSION: JXR extract has significant antioxidant capacity in vitro.
文摘以产自山西的藜麦为研究对象,以对DPPH·和ABTS+·的清除能力、铁还原力等为指标,评价了其提取物的体外抗氧化活性。结果表明,藜麦提取物对DPPH·和ABTS+·均有较强的清除能力,其IC_(50)分别为(43.13±2.41)mg/m L和(27.91±1.46)mg/m L;FRAP法测得藜麦抗氧化能力为(1.90±0.10)mg Fe SO_4/g;此外,藜麦提取物能够有效抑制自由基引发的亚油酸过氧化和牛血清白蛋白氧化降解。藜麦提取物具有较强的体外抗氧化活性,为其体内抗氧化活性的研究奠定了基础。
