不同品种酿酒葡萄皮渣提取物的体外抗氧化活性测定

研究以东北特产的不同品种的酿酒葡萄为原料,对其皮渣葡萄提取物的抗氧化活性进行研究。以抗坏血酸为对照,通过测定不同浓度的东北特产酿酒葡萄提取物对羟自由基清除率、超氧阴离子自由基清除率、还原能力和脂质体的抗氧化能力,研究东北特产酿酒葡萄皮渣提取物的抗氧化能力。三种酿酒葡萄皮渣提取物都具有一定的抗氧化活性,尤其在清除羟自由基、清除超氧阴离子自由基、抗脂质体过氧化抑制率方面。双优品种皮渣提取物抗氧化活性均高于左山一品种和双红品种,且抗氧化活性随着浓度的增加而增大。但三种酿酒葡萄提取物在还原能力方面没有显著性差异。东北特产酿酒葡萄皮渣提取物具有较强的抗氧化活性,具有产品开发和应用前景。     

豆腐柴叶总黄酮不同溶剂级分抗氧化活性分析

采用1,1-二苯基-2-三硝基苯肼自由基、羟自由基、超氧阴离子、还原力、总抗等体外抗氧化活性模型和抗氧化活性综合评价指数,分析四川江油地区不同溶剂萃取的豆腐柴黄酮级分(乙醇、乙酸乙酯、正丁醇、氯仿、水)的抗氧化活性。结果显示,不同浓度乙醇提取总黄酮的1,1-二苯基-2-三硝基苯肼自由基清除活性最高。1,1-二苯基-2-三硝基苯肼自由基清除率、羟基自由基清除率、ABTS阳离子自由基清除率、总抗和还原力皆随乙醇浓度的升高而呈现先增强后减弱的趋势,超氧阴离子自由基清除率却随乙醇浓度增加一直降低。综合评价指数显示不同浓度乙醇抗氧化活性依次为75%醇提物65%醇提物55%醇提物85%醇提物95%醇提物。乙酸乙酯层萃取物的1,1-二苯基-2-三硝基苯肼自由基清除率、总抗、还原力及ABTS阳离子自由基清除率要优于其它各萃取层。正丁醇层萃取物的超氧阴离子自由基清除率要优于其它各萃取层。乙酸乙酯层抗氧化活性最佳。豆腐柴叶总黄酮有较好的抗氧化活性,可作为抗氧化剂或者健康食品原料开发。     

水栒子果肉黄酮的体外抗氧化活性研究

以水栒子果肉总黄酮的粗提物为原料,测定其体外抗氧化能力。利用匀浆法提取水栒子果肉黄酮,比色法测定其含量。采用1,1-二苯基-2-三硝基苯肼（DPPH）自由基清除法、2,2-吖嗪双（3-乙基-7-苯并噻唑啉磺酸）二铵盐（ABTS）自由基清除法、超氧阴离子自由基清除法（SRSA）、还原能力测定法和铁离子还原/抗氧化能力法（FRAP）,对其进行体外抗氧化活性研究。结果表明,水栒子果肉总黄酮的自由基清除能力和还原能力随总黄酮浓度的升高而增强,DPPH自由基清除能力和超氧阴离子自由基（O-2·）清除能力与特丁基对苯二酚（TBHQ）相当,高于丁基羟基甲苯（BHT）、丁基羟基茴香醚（BHA）、VC、VE;ABTS清除能力高于BHT、VC、VE,略低于TBHQ和BHA;还原能力与TBHQ相当,高于BHT、VE,略低于BHA和VC;铁还原能力与TBHQ相当,高于BHT、VC、VE,低于BHA。水栒子果肉黄酮有较强的体外抗氧化能力,具有很好的开发潜力。     

双水相分离与超声提取耦合从冬瓜籽中提取抗氧化活性物质

利用丙醇-硫酸铵双水相体系与超声耦合技术对冬瓜籽中抗氧化活性物质进行提取分离试验,结果显示:提取物对光照核黄素超氧阴离子自由基和Fenton反应羟自由基的清除率分别为67.0%、88.0%,对卵磷脂脂质过氧化的抑制率为69.1%,该法提取物抗氧化活性高于乙醇、乙酸乙脂回流提取法,活性成分初步鉴定为酚类、皂苷、有机酸等。     

蓝莓皮渣花色苷粗提物的抗氧化性

从蓝莓加工废弃物-皮渣中提取花色苷粗提物,研究花色苷粗提物清除超氧阴离子自由基、DPPH自由基、羟自由基和抗脂质氧化、还原力等活性。结果表明:蓝莓皮渣花色苷粗提物对超氧阴离子自由基、DPPH自由基、羟自由基的清除率和还原能力随着添加浓度的增大而升高。花色苷粗提物的羟自由基抑制率在同等浓度下与标准抗氧化剂VC相近、对脂质的抗氧化作用比标准抗氧化剂BHT和VC表现出更好的活性,但花色苷粗提物显著低于同浓度VC对DPPH自由基的清除率。通过与VC、刺梨多糖的协同作用分析发现,VC对蓝莓皮渣花色苷粗提物具有更好的协同作用。因此,蓝莓皮渣花色苷粗提物具有一定的还原能力、较强的抗脂质过氧化能力,并对自由基具有较强的清除效果,为贵州省蓝莓皮渣的综合开发及新型食品添加剂的研制及进一步推广应用提供了依据。     

油梨仁提取物的体外抗氧化活性研究

试验研究了油梨仁提取物的体外抗氧化活性。以VC为对照品,采用羟自由基清除法、超氧阴离子自由基清除法、DPPH自由基清除法、ABTS自由基清除法以及铁氰化钾还原法评价油梨仁提取物的体外抗氧化活性。结果表明,油梨仁提取物对超氧阴离子自由基和DPPH自由基具有较强的清除作用,其IC50分别为0.025 mg/m L和0.086mg/m L,且其还原能力与VC相当;而对羟自由基和ABTS自由基的清除能力相对较弱。     

枸杞叶黄酮类化合物体外清除自由基作用研究

采用有机溶剂浸提法(70%乙醇)提取枸杞叶中的黄酮类化合物,然后以枸杞叶黄酮提取物为研究对象,以Vc和BHT为阳性对照,通过自由基清除实验体外评价产物的抗氧化活性。结果表明:枸杞叶黄酮提取物中黄酮类化合物的含量为277.7mg/g。枸杞叶黄酮提取物对超氧阴离子自由基、羟基自由基、DPPH~+、亚硝基自由基、ABTS+具有显著的清除能力,其最大清除率分别为62%,84%,80%,34%,78%,对Fe~(3+)的还原能力达到Vc和BHT还原能力的50%。结论:所提取的枸杞叶黄酮类化合物具有较高的体外抗氧化活性,可为枸杞叶黄酮类化合物资源的开发利用提供依据。     

双水相分离与超声提取耦合法从葡萄籽中提取抗氧化活性物质研究

利用丙醇-硫酸铵双水相体系与超声耦合法时葡萄籽中抗氧化活性物质进行提取分离.结果表明,该法可有效地从葡萄籽中提取抗氧化活性物质,提取物具有良好的抗氧化活性;提取物对光照核黄素超氧阴离子自由基和Fenton反应羟自由基的清除率分别为75.0%和92.0%,对卵磷脂脂质过氧化物的抑制率为74.5%.该法提取物的抗氧化活性高于乙醇、乙酸乙酯回流提取法提取物的抗氧化活性.该法操作简便、条件温和、环境友好.     

不同季节角叉菜乙醇提取物的抗氧化活性

本实验分别对同一地点春季和秋季采集的角叉菜样品采用95%乙醇进行提取.采用化学方法产生超氧阴离子自由基、羟自由基和小鼠肝匀浆液脂质过氧化体系对提取物进行抗氧化活性检测,研究其清除自由基和抑制脂质过氧化能力的差异.结果表明:春秋季节角叉菜样品的乙醇提取物对超氧阴离子自由基、羟自由基具有较显著的清除作用,同时对小鼠肝匀浆液的脂质过氧化作用也有一定的抑制作用.     

芦蒿不同部位清除自由基活性研究

考察芦蒿中不同部位活性成分的提取及其抗氧化清除自由基的性能。芦蒿的秸秆、花、叶、茎经过粉碎,烘干,石油醚脱色后,用60%的乙醇为提取剂提取活性成分,通过定性定量试验测定黄酮类化合物的含量,并对照抗坏血酸探讨了芦蒿不同部位醇提物的抗氧化活性,包括还原能力,螯合能力以及清除DPPH自由基、清除羟基自由基、清除超氧阴离子能力。结果表明:芦蒿各部位提取物其抗氧化清除自由基由强到弱排序为叶提取物>花提取物>茎提取物>秸秆提取物;对自由基清除能力排序分别为超氧阴离子、DPPH、羟自由基。芦蒿各部位提取物均具有还原性,抗氧化及清除不同自由基性能。     

橄榄酚类提取物的抗氧化性能

为进一步开发利用橄榄中的酚类物质,文中通过测定橄榄酚类提取物的铁离子还原能力、亚铁离子螯合能力,及对2,2'-氨基-二(3-乙基-苯并噻唑啉-6-磺酸)自由基(ABTS+.)、1,1-二苯-2-苦基苯肼自由基(DPPH.)、羟基自由基(.OH)和超氧阴离子自由基(O2-.)的清除能力,以考察橄榄酚类提取物的体外抗氧化性能,并与食品抗氧化剂丁基羟基茴香醚(BHA)和Vc进行对比。结果表明:橄榄酚类提取物具有较好的体外抗氧化性能,其ABTS+.、DPPH.清除率分别高达99%和95%以上,.OH、O2-.清除率可达50%左右,铁离子还原力约1 700μmol/L Trolox,亚铁离子螯合率最高为14.9%。且提取物ABTS+.、DPPH.和.OH清除能力及铁离子还原能力均强于BHA和Vc,而O2-.清除能力强于BHA但弱于Vc。另外,橄榄酚类粗提物和纯化物相同浓度下的ABTS+.、DPPH.、.OH清除能力和铁离子还原能力相当(P>0.05),而其O2-.清除能力和亚铁离子螯合能力表现有所差异。     

牡蛎水提液的抗氧化特性

研究了低温条件下制备牡蛎水提液体外抗氧化特性,及牡蛎水提液清除二苯代苦味酰自由基(DPPH·)、Feton体系产生的羟基自由基(·OH)、邻苯三酚自氧化体系产生的超氧阴离子自由基(O2 -·)的能力,以Fe2 +诱发脂蛋白PUFA过氧化体系研究牡蛎水提液的抗氧化活性。结果表明,牡蛎水提液具有较强的清除自由基能力,并有一定的抗脂质过氧化作用     

Comparison of antioxidant activity of clove (Eugenia caryophylata Thunb) buds and lavender (Lavandula stoechas L.)

The antioxidant activity of water and ethanol extracts of clove (Eugenia carophyllata) buds and lavender (Lavandula stoechas L.) was studied. The antioxidant properties of both extracts of clove and lavender were evaluated using different antioxidant tests; reductive potential, free radical scavenging, superoxide anion radical scavenging and metal chelating activities. The both extracts of clove and lavender exhibited strong total antioxidant activity. At the concentrations of 20, 40, and 60 μg/ml, water extract of clove and lavender showed 93.3%, 95.5%, 97.9%, 86.9%, 92.3%, and 94.8% inhibition on lipid peroxidation of linoleic acid emulsion, respectively. At the same concentrations, ethanol extract of clove and lavender exhibited 94.9%, 95.5%, 98.2%, 92.5%, 93.8%, and 96.5%, respectively. Comparable, 60 μg/ml of standard antioxidant such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and α-tocopherol exhibited 96.5%, 99.2%, and 61.1% inhibition on peroxidation of linoleic acid emulsion, respectively. The both extracts of clove and lavender had effective reductive potential, free radical scavenging, superoxide anion radical scavenging, and metal chelating activities at all tested concentrations (20, 40, and 60 μg/ml). Those various antioxidant activities were compared to standard antioxidants such as BHA, BHT, and α-tocopherol. In addition, total phenolic compounds in the both extracts of clove and lavender were determined as gallic acid equivalent.     

Determination of antioxidative potential of lichen Usnea ghattensis in vitro

The study was aimed at evaluating the antioxidant activities of extract of Usnea ghattensis. The antioxidant activity, reducing power, superoxide anion radical scavenging and free radical scavenging activities were studied. The antioxidant activity increased with the increasing amount of extracts (2-20 mg/ml) added to the linoleic acid emulsion. Lipid peroxidation upto 73.3% was inhibited by the extract of 20 mg/ml and 39.2% by α-tocopherol at the same concentration. These effects were statistically significant (r²=0.876,P<0.01) when compared with control. However, the extract had no significant effect on superoxide anion scavenging by the PMS/NADH-NBT method. Like antioxidant activity, the reducing power and free radical scavenging activity of extract depends on concentration and increasing with increased amount of sample. The reducing power and DPPH radical-scavenging activity of U. ghattensis extract were found greater than the BHA and BHT. The results obtained in the present study indicate that U. ghattensis is a potential source of natural antioxidant.     

高钙菜黄酮的分级分离各级分的抗氧化活性

以抗坏血酸和叔丁基羟基茴香醚做阳性对照,采用二苯代苦味肼基自由基(DPPH·)、羟自由基(·OH)、超氧阴离子自由基(O₂-·)、还原力、2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐阳离子自由基(ABTS+·)和总抗体外抗氧化模型,主成分分析综合评价高钙菜总黄酮各级分(乙酸乙酯相、正丁醇相、氯仿相和水相)的抗氧化活性。结果显示,在各体外抗氧化活性指标的测定中,各萃取相的抗氧化活性均随着黄酮浓度增加呈现上升趋势,其中ABTS+·的清除能力最强,高达99.72%±0.10%,与抗坏血酸清除能力相近。乙酸乙酯相的·OH清除率、O₂-·清除率、总抗氧化FRAP值、还原力及ABTS+·清除率要显著优于其它各萃取相,氯仿相的DPPH·清除率显著优于其它萃取相。主成分分析综合评价显示,乙酸乙酯相抗氧化活性最佳。显色反应结合红外光谱分析,初步判定乙酸乙酯相和正丁醇相可能为黄酮醇类。高钙菜总黄酮具有较强的抗氧化活性,可作为良好的健康食品原料开发及利用。     

Screening of antioxidant and antimicrobial activities of anise (Pimpinella anisum L.) seed extracts

In this study, antioxidant and antimicrobial activities of water and ethanol extracts of anise (Pimpinella anisum L.) seed (PAS) were investigated. The antioxidant properties of both extracts of PAS were evaluated using different antioxidant tests, including reducing power, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, and metal chelating activities. Twenty μg/ml of water and ethanol extracts exhibited 99.1 and 77.5% inhibition of peroxidation in linoleic acid system, which was greater than the same concentration of α-tocopherol (36.1%). These various antioxidant activities were compared with synthetic antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and α-tocopherol. The water extract of PAS exhibited greater antioxidant capacity than that of ethanol. Antimicrobial activity tests were carried out using disc diffusion methods with 10 microbial species.     

Antioxidant activity of stem and root extracts of Rhubarb (Rheum ribes): An edible medicinal plant

The antioxidant activity of chloroform and methanol extract of roots and stems of Rhubarb (Rheum ribes L.), which are used for medicinal purposes and also its fresh stems and petioles are consumed as vegetable, was studied. The antioxidant potential of both extracts of roots and stems were evaluated using different antioxidant tests, namely total antioxidant (lipid peroxidation inhibition activity), DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging, superoxide anion radical scavenging, ferric reducing power, and cupric reducing power (CUPRAC), and metal chelating activities. Total antioxidant activity was also measured according to the β-carotene bleaching method, and all four extracts exhibited stronger activity than known standards, namely butylated hydroxytoluene (BHT) and α-tocopherol. Particularly, higher activity was exhibited by roots with 93.1% and 84.1% inhibitions of chloroform and methanol extracts, while 82.2% and 82.0% inhibitions by stem extracts, respectively. However, both methanol extracts exhibited higher DPPH radical scavenging activity than the corresponding chloroform extracts, moreover, methanol extract of the stems showed better activity than BHT. In addition, both root extracts showed more potent superoxide anion radical scavenging activity than BHT, and comparable with well known radical scavenger l-ascorbic acid. Except chloroform extract of the roots, the other three extracts exhibited better metal chelating activity than quercetin. Also, total phenolic and flavonoid contents in both extracts of the roots and stems of R. ribes were determined as pyrocatechol and quercetin equivalents, respectively.     

Antioxidant effects of solvent extracts from the dried jujube (Zizyphus jujube) sarcocarp,seed, and leaf via sonication

Antioxidant effects of extracts from sarcocarp, seed, and leaf of dried jujube (Zizyphus jujube) were investigated. The highest amount of flavonoids and polyphenol was found in 80% methanol leaf extract at value of 43.04±0.34 and 324.75±6.01 mg/g, respectively. For 2,2′-azino-bis-3-ethylbenzo-thiazoline-6-sulfonic acid (ABTS) radical scavenging activity analysis at a concentration of 1,000 μg/mL, 70% ethanol seed extract (94.76±0.23%), and 80% methanol leaf extract (95.46±0.14%) were observed to have higher activity than those of controls, such as butylated hydroxyl anisole (BHA) (89.60±0.00%), butylated hydroxyl toluene (BHT) (84.07±0.50%), vitamin C (89.27±0.12%), and vitamin E (88.53±0.12%). All solvent extracts from leaf showed higher ABTS radical scavenging activity (over 98%) than those of controls with their activity values around 94% (500 g/mL). All extracts from sarcocarp and seed showed superoxide dismutase (SOD)-like activity of 24.46–34.84% on the concentrations (100–1,000 g/mL), and 80% methanol leaf extract showed the highest activity (43.66±0.37%) among samples. These results indicate that sarcocarp, seed of dried jujube are all excellent antioxidants, and especially leaf showed higher antioxidant effect than those of vitamin C and E.     

Antioxidant activities of red pepper (Capsicum annuum) pericarp and seed extracts

In this study, we examined the antioxidant activities of red pepper (Capsicum annuum, L.) pericarp and red pepper seed extracts. The extracts were evaluated by various antioxidant assays, including 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging, superoxide anion radical scavenging, hydroxyl radical scavenging, [2,2′‐azino‐bis(3‐ethylbenzthiazoline‐6‐sulphonic acid)] (ABTS) radical scavenging, ferrous chelating activity, superoxide dismutase (SOD) activity and reducing power, along with the determination of total phenolic and flavonoid contents. All the extracts showed strong antioxidant activity by the testing methods. The red pepper pericarp extract exhibited strong ferrous chelating activity and high scavenging activity against free radicals, including both the hydroxyl and DPPH radicals, but it exhibited weaker scavenging activity for the superoxide anion radical and for SOD. In contrast, the red pepper seed extract exhibited strong SOD activity and high scavenging activity against the superoxide anion radical, but showed weaker ferrous chelating activity, hydroxyl radical scavenging, and DPPH radical scavenging. We observed that the reducing power level and ABTS radical scavenging activity of the red pepper seed were higher than those of the red pepper pericarp at the highest tested concentration. Most of the test results for the red pepper seed and red pepper pericarp extracts increased markedly with increasing concentration; however, the metal chelating, SOD and ABTS radical scavenging activities did not increase with the concentration. Highest total phenolic and flavonoid contents were obtained from the red pepper pericarp extracts. Overall, the red pepper seed and red pepper pericarp extracts were highly effective for the antioxidant properties assayed, with the exceptions of ferrous chelating activity, hydroxyl radical scavenging and SOD activity.