苦荞纳豆酱的抗氧化活性

为研究苦荞纳豆酱总黄酮和总酚的体外抗氧化活性,测定DPPH自由基清除率、ABTS+·清除率、·OH清除率、O2－·清除率和Fe3+还原能力,并且与黄豆酱、甜面酱进行抗氧化活性比较研究。结果表明：苦荞纳豆酱的DPPH自由基清除率、ABTS＋·清除率、·OH清除率、O2 － ·清除率均高于黄豆酱和甜面酱;Fe3+还原能力略低于甜面酱。被测样品的抗氧化活性与总黄酮、总酚的含量有显著相关性（P＜0.01）。     

鲍鱼壳水溶性基质抗氧化活性研究

考察鲍鱼壳水溶性基质(WSMA)抗氧化活性。利用DEAE-Sephadex A-25 离子交换层析法(IEC)对WSMA进行纯化。以珍珠水溶性基质(WSMP)及VC 为对照,通过对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·)的清除能力和Fe3+ 还原能力的研究考察其抗氧化作用。结果表明,WSMA 与WSMP 具有相似的Fe3+ 还原能力和O2·清除能力,而对DPPH·和·OH 无清除作用。通过IEC 纯化得到的AⅡ组分为主要活性成分,当质量浓度为1.0mg/mL 时,对O2·清除率达80%,与0.1mg/mL 的VC 相当。     

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。     

凤头姜醇溶和水溶黄酮的抗氧化作用

比较凤头姜水溶和醇溶黄酮对超氧阴离子自由基、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基、2’-联氨-双-3-乙基苯并噻唑啉-6-磺酸(2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid),ABTS)自由基的清除能力和总抗氧化能力(铁离子还原能力法),同时用VC和2,6-二叔丁基对甲酚(butylated hydroxytoluene,BHT)作对照。结果表明:在DPPH自由基清除能力测定中,水溶黄酮的抗氧化效果强于醇溶黄酮和BHT,但弱于VC,水溶和醇溶黄酮的半抑制浓度(half maximal inhibitory concentration,IC_(50))分别为585.75μg/m L和1 013.45μg/m L;在ABTS+·、超氧阴离子自由基清除能力和总抗氧化能力测定中,醇溶黄酮的抗氧化效果均强于水溶黄酮、VC和BHT,醇溶和水溶黄酮对ABTS+·的IC_(50)分别为21.90μg/m L和87.54μg/m L;在超氧阴离子自由基清除能力测定中,水溶和醇溶黄酮的IC_(50)分别为26.56μg/m L和22.29μg/m L;在铁离子还原能力测定中,水溶黄酮和醇溶黄酮的TEAC1 000分别为45.78μg/m L和36.42μg/m L。综合研究发现,凤头姜水溶黄酮和醇溶黄酮在不同抗氧化体系中的抗氧化效果存在差异。     

鸡骨胶原蛋白肽抗氧化性的研究

选取具有代表性的·OH、DPPH·、O2·三种自由基体系和铁离子还原体系,以不同浓度鸡骨胶原蛋白肽的抗氧化作用作为指标,评价鸡骨胶原蛋白肽的抗氧化性能。结果显示：鸡骨胶原蛋白肽对三种自由基都具有明显的清除作用,在相应浓度范围内,·OH 最大清除率为99.74%,半抑制浓度IC50 为 4.85mg/ml;DPPH·最大清除率为80.24%,IC50= 32.06μg/ml;O2·最大清除率为53.71%,IC50=16.48μg/ml。同时,对铁离子还具有显著的还原能力。     

硬脂酰氯改性对核桃青皮多酚纯化物抗氧化功效的影响

通过对比核桃青皮多酚纯化物及其硬脂酰氯改性产物的还原力、体外清除自由基能力以及抗油脂氧化能力,分析硬脂酰氯改性对核桃青皮多酚纯化物抗氧化功效的影响。结果表明:核桃青皮多酚纯化物具有较强的抗氧化能力;在所选的浓度范围中,除了DPPH自由基清除率外,核桃青皮多酚纯化物和改性后的物质的还原力、羟基自由基、ABTS自由基与亚硝酸盐清除能力以及抗油脂氧化能力均大于V_C和BHT;核桃青皮多酚纯化物改性后,其还原力和体外清除自由基能力均低于改性前,但其抗油脂氧化能力比改性前增强。     

沂州木瓜种仁油脂体外抗氧化能力研究

通过ABTS+·自由基清除实验、二苯代苦味酰基自由基清除实验、羟基自由基清除实验以及花生油的抗氧化实验,测定和对比沂州木瓜种仁油脂(SOYC)、BHT、维生素C和Trolox的抗氧化能力。结果表明,10%的沂州木瓜种仁油脂对ABTS+·自由基清除能力的TEAC值为65.67μmol/L;沂州木瓜种仁油脂对二苯代苦味酰基自由基和羟基自由基的清除效果比100μg/mL的BHT好,对花生油的抗氧化效果明显,说明沂州木瓜种仁油脂具有显著的抗氧化活性。     

葡萄籽原花青素聚合度与自由基清除能力关系的研究

采用DPPH·及化学发光法,研究葡萄籽原花青素不同聚合度组分的自由基清除能力。结果表明,原花青素对DPPH·的清除能力优于VC、VE及BHT,半抑制浓度分别为:原花青素1.8μg/ml、VC2.5μg/ml、VE6.3μg/ml、BHT3.5μg/ml。对O2·的清除能力优于VE而与VC相近。以质量浓度(μg/ml)表示时,原花青素对DPPH·的清除作用与聚合度无关,对HO·、O2·的清除能力随着聚合度的升高而下降。但以摩尔浓度(μmol/L)表示时,原花青素的自由基清除能力基本上随着聚合度的增加而提高。原花青素的抗氧化和自由基清除能力可能与所处的溶剂环境有关,水相体系中原花青素分子中单位酚羟基的活性随着聚合度的增加而下降。     

木瓜抗氧化活性研究

采用DPPH法、ABTS法和FRAP法三种测定法对木瓜叶和木瓜果实体外抗氧化活性进行综合评价,并分析其总多酚与总黄酮含量与抗氧化活性的关系。结果表明:木瓜6个提取物中,木瓜叶乙酸乙酯部位清除ABTS自由基及还原Fe3+(IC50=6.66μg/mL,TEAC=1293.25μmol/g)最强,其中,清除ABTS自由基活性和阳性对照BHT(IC50=6.56μg/mL)相当,还原Fe3+能力低于BHT(TEAC=2503.17μmol/g);木瓜果实乙酸乙酯部位清除DPPH自由基(IC50=48.99μg/mL)能力最强,弱于阳性对照BHT(IC50=24.49μg/mL)。木瓜叶乙酸乙酯部位清除ABTS自由基及还原Fe3+的能力可能与其多酚、黄酮含量高有关,木瓜果实乙酸乙酯部位清除DPPH自由基的能力可能也与其多酚、黄酮含量高有关。     

马兰头黄酮粗提物对油脂的抗氧化活性研究

目的 分析马兰头黄酮粗提物对油脂的抗氧化性能及体外自由基清除能力。方法 以酸价、过氧化值为指标, 分析2,6二叔丁基对甲酚(butylated hydroxytoluene, BHT)、马兰头黄酮粗提物对花生油、大豆油、猪油的抗酸败氧化性能; 以抗坏血酸为对照, 分析马兰头黄酮粗提物对2,2’-联氮-双-3-乙基苯并噻唑-6-硫酸二铵盐[2,2''-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid), ABTS+]自由基的清除能力。结果 马兰头黄酮粗提物可以有效抑制油脂酸价的升高, 可分别将猪油、大豆油的过氧化值超标耐受天数从3、4 d延长至4、5 d, 与BHT作用效果差异不显著(P>0.05), 它对花生油过氧化值的升高抑制作用无实际应用意义; 马兰头黄酮粗提物水溶液对ABTS+自由基清除率最高可达到104.0%±0.9%。结论 马兰头黄酮粗提物具有较好的抑制油脂氧化的作用和很好的自由基清除能力, 具有较好的天然油脂抗氧化剂开发前景。     

天然生姜复合物体外抗自由基活性研究

以生姜提取物为主要原料,通过二组分优化组合和体外抗自由基活性研究,研制一种对羟自由基和DPPH自由基有显著清除作用的二组分天然生姜复合抗氧化剂。结果表明：不同组成生姜复合物清除自由基的能力与其黄酮和酚类物质含量成正相关,且复合物一般强于单一组分,表现出组分间的协同效应;而清除自由基的能力最强的二组分天然生姜复合抗氧化剂的组成为生姜提取物+ 茶叶提取物,最佳质量配比为：生姜提取物:茶叶提取物为1.35:1(m/m),该天然生姜复合抗氧化剂清除自由基的能力明显强于合成的抗氧化剂BHT 和PG。     

菟丝子黄酮成分分析及对食用油脂的抗氧化活性

采用紫外光谱和高效液相色谱法,对菟丝子中主要黄酮成分,即芦丁、槲皮素、山奈酚进行定性、定量分析。以芦丁为标准品,紫外光谱测定菟丝子黄酮提取物,与芦丁标准品乙醇溶液相同,在300～380nm和240～280nm有两个吸收峰,可以确定提取物属于黄酮类化合物;采用高效液相色谱法准确的测定出3种黄酮成分的含量,且重现性好,说明该方法是可靠的。以过氧化值(POV)为指标,以猪油和花生油为介质研究菟丝子黄酮的抗氧化性能。结果表明:菟丝子黄酮对食用油脂有较强的抗氧化作用,且抗氧化效果与添加量有关;在猪油和花生油中,当菟丝子黄酮添加量分别达到0.08%和0.06%时抗氧化效果已高于0.02%BHT和0.01%PG。     

Antioxidant activity of ginger extract in sunflower oil

The antioxidant activity of dichloromethane extract from ginger was evaluated during 6 months of storage of refined sunflower oil at 25 and 45 °C. Free fatty acid (FFA) content, peroxide value (POV) and iodine value (IV) were used as criteria to assess ginger extract as an antioxidant. After 6 months of storage at 45 °C, sunflower oil containing 1600 and 2400 ppm ginger extract showed lower FFA contents (0.083 and 0.080%) and POVs (24.5 and 24.0 meq kg^?1) than the control sample (FFA contents 0.380%, POV 198.0 meq kg^?1). Sunflower oil containing 200 ppm butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) showed FFA contents of 0.089 and 0.072% and POVs of 26.5 and 24.7 meq kg^?1 respectively after 6 months of storage at 45 °C. Similarly, after 6 months of storage at 45 °C, IVs of sunflower oil containing 1600 and 2400 ppm ginger extract were 80 and 92 respectively, higher than that of the control sample (53). However, IVs of sunflower oil treated with 200 ppm BHA and BHT were 94 and 96 respectively after 6 months of storage at 45 °C. These results illustrate that ginger extract at various concentrations exhibited very strong antioxidant activity, almost equal to that of synthetic antioxidants (BHA and BHT). Ginger extract also showed good thermal stability and exhibited 85.2% inhibition of peroxidation of linoleic acid when heated at 185 °C for 120 min. Therefore the use of ginger extract in foods is recommended as a natural antioxidant to suppress lipid oxidation. © 2003 Society of Chemical Industry     

Antioxidant activity of natural plant sources in dairy dessert (Sandesh) under thermal treatment

Natural sources of antioxidant viz. beet (Beta vulgaris), mint (Mentha spicata L.) and ginger (Zingiber officinale L.) have been used to fortify sandesh (a heat desiccated product of coagulated milk protein mass called chhana which is in turn a heat and acid coagulated product of milk, analogous to cottage cheese). Three sets of experiments viz. antioxidant activity, peroxide value and ultra-violet absorbance were done to evaluate the effectiveness of natural antioxidants in reducing lipid oxidation in sandesh as compared to synthetic antioxidants like tertiary butyl hydroquinone (TBHQ), butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) under thermal treatment. Among the natural sources, ginger has the highest antioxidant activity and it was similar to TBHQ and BHA-BHT combined. Results of the antioxidant activity differed from those of the oven test at 63 °C particularly for ginger and BHA-BHT combined. Control sandesh (without any antioxidants) showed the highest peroxide value and ultra-violet absorption. All the natural sources and their combinations significantly improved the oxidative stability of sandesh and their effectiveness was comparable with synthetic antioxidant TBHQ, a combination of BHA and BHT. Among the natural sources, although ginger had the highest antioxidant activity but mint showed better effectiveness in the inhibition of lipid oxidation. Regarding antioxidant activity and lipid oxidation, combination of mint or ginger with beet showed better result as compared to beet alone. Besides, sensory evaluation of freshly prepared natural source fortified sandesh samples was done as compared to control sandesh in order to commercialize the herbal sandesh in market. Sandesh containing beet, ginger, combination of beet with ginger or mint, or combination of mint with ginger were more acceptable to panelist than control sandesh.     

A process for preparing a natural antioxidant enriched dairy product (Sandesh)

The antioxidant activities of beet (Beta vulgaris), mint (Mentha spicata L.) and ginger (Zingiber officinale L.) alone or in combination were assessed after their fortification in sandesh (a heat desiccated product of coagulated milk protein mass) using Randox's total antioxidant level determining chemicals and ultimately it was compared with the synthetic antioxidants like TBHQ, BHA and BHT. Addition of beet or mint alone in sandesh showed lower antioxidant level than the addition of ginger alone. However, combination of beet with ginger showed highest antioxidant level among the natural sources and value was almost equal to TBHQ (200 mg kg⁻¹). Besides, the suitable stage and form of addition of these herbs in sandesh were also investigated using the Randox's antioxidant level evaluating chemical. Among the four forms of herbs such as paste, tray-dried powder, freeze-dried powder and solvent extracted form, addition of solvent extracted form in sandesh showed highest antioxidant level than any other form. Similarly, addition of all these herbs at final stage of sandesh preparation showed highest antioxidant level than their addition at the initial stage of sandesh preparation. Comparative evaluations of the proximate composition of herbal sandesh with the control sandesh showed that herbal sandesh were more or less similar with control sandesh except in fat and moisture content. But according to sensory characteristics, sandesh containing beet, ginger or combination of beet with ginger or mint was more acceptable to panelist than control sandesh. Results of the study indicate that herbal sandesh is more value added health food than control sandesh.     

五倍子制备没食子酸丙酯的抗氧化活性研究

对天然植物五倍子浸提物没食子酸（GA）进行改性,得到没食子酸丙酯（PG）,并采用亚铁还原能力法（FRAP）、1,1-二苯基-2-三硝基苯肼（DPPH）自由基法、2-联氨-双-3-乙基苯并噻唑啉-6-磺酸（ABTS）自由基法对其抗氧化活性进行评价。结果显示,FRAP值由大到小排序为：PG（FRAP值0.506）＞TBHQ（FRAP值0.412）＞BHA（FRAP值0.409）＞BHT（FRAP值0.067）;DPPH自由基清除能力由强到弱的顺序为：PG（IC50值4.2 μmol/L）＞BHT（IC50值53 μmol/L）＞TBHQ（IC50值87 μmol/L）＞BHA（IC50值816 μmol/L）;ABTS自由基清除能力由强到弱的顺序为：PG（IC50值 4.2 μmol/L）＞BHA（IC50值44 μmol/L）＞BHAT（IC50值45 μmol/L）＞TBHQ（IC50为50 μmol/L）。结果表明,PG的抗氧化活性均强于其他三种抗氧化剂,可作为新兴食品抗氧化剂应用。     

浓香大豆油的开发及其氧化稳定性的研究

建立一种新型浓香大豆油(ASO)的生产方法。采用超临界萃取技术对焙烤后的大豆进行提取。通过感官评定对大豆焙烤工艺进行评估：在温度170℃条件下烘烤30min 时,焙烤出的大豆具有浓郁的香味。ASO 的萃取率随着大豆粉粒度的增加而提高,大豆粉的粒度为40～60 目时最佳。采用正交试验设计法对ASO 的萃取参数进行研究：萃取率随着温度的升高,先增大后减小,最佳萃取温度为50℃;萃取率随着压力的增大,先增大后减小,最佳萃取压力为25MPa;萃取率随着时间延长逐渐趋于最大值,确定萃取时间为2.5h。通过对氧化诱导期(IP 值)和抗氧化保护系数(Pf 值)的分析,探讨ASO 的氧化稳定性：ASO 和市售大豆油的IP 值分别为8.93、9.47,其他植物油均大于16;向ASO 中添加0.04% 的BHT、PG 分别能使其IP 值从8.93 提高到12.08、18.55,Pf 值分别达到1.353 和2.077,PG 对ASO 的抗氧化效果要明显优于BHT;在ASO 中单独添加0.01% 柠檬酸能使其Pf 值达到2.25,显示较强的抗氧化能力,复合添加0.01% 柠檬酸和0.04% PG 使其Pf 值达到4.14,显示很强的抗氧化能力。     

Qualitative and Quantitative Effects of Antioxidants on the Flavor Stability of Oil

Qualitative and quantitative effects of the common antioxidants, BHA, BHT, PG and TBHQ on the rate of dissolved free oxygen disappearance in soybean oil during storage were studied. The order of effectiveness was BHA, BHT, PG and TBHQ with TBHQ as the most effective. Statistical analyses of the results showed that the effects of BHA and BHT were not significantly different from each other at the 5% level, but BHA or BHT was different from PG or TBHQ, and PG was different from TBHQ. The antioxidant effectiveness of levels of 0, 50, 100, 150 and 200 ppm BHA, BHT, PG or TBHQ was significantly different from one another at the 5% level. The higher the amounts of antioxidants added, the slower the rate of dissolved oxygen disappearance in the oil.     

生姜中姜酚的性能研究

采用超临界流体萃取-精馏技术从生姜中提取有效成分姜酚,研究了姜酚的溶解性、紫外吸收光谱和抗氧化性。结果表明,姜酚易溶于醚、醇等有机溶剂,不溶于水;该物质在280nm处有特征吸收;姜酚对猪油具有较强的抗氧化作用,且存在剂量效应关系;相同添加量时,其抗氧化能力优于Vc、VE及合成抗氧化剂PG、BHA、BHT;与Vc、VE复合使用时,二者对姜酚的抗氧化性均具有协同增效作用。     

富勒烯[C60] 作为油脂抗氧化剂的研究

研究富勒烯[C60]对油脂的抗氧化效果。通过烘箱加热法研究富勒烯[C60]与叔丁基对苯二酚(TBHQ)、二丁基羟基甲苯(BHT)、没食子酸丙酯(PG)、V_E对橄榄油、文冠果油、亚麻籽油和猪油的过氧化值和防护因子PF20的影响并进行加热实验。结果表明,在亚麻籽油和文冠果油中的抗氧化效果为:TBHQ富勒烯[C60]PGBHTV_E;在橄榄油中的抗氧化效果为:富勒烯[C60]TBHQPGBHTV_E;在猪油中的抗氧化效果为:TBHQPGBHT富勒烯[C60]V_E。在加热实验中,添加抗氧化剂的油脂均没有析出物且色值不发生变化。表明富勒烯[C60]在油脂中具有很好的抗氧化性能,可作为食品加工、生产与储存中油脂的抗氧化剂。