草苁蓉多糖抗氧化活性研究

研究草苁蓉多糖(BRPS)的抗脂质过氧化活性。以铁还原法检测BRPS的总抗氧化能力,以硫代巴比妥酸(TBA)法测定H2O2、Fe2+以及.OH所致肝匀浆丙二醛(MDA)生成量。结果表明,BRPS具有较强的总抗氧化能力,其总抗氧化能力随浓度增高而升高,回归方程为y=21.988x+1.1247,R2=0.9996;呈量效关系。同时,BRPS可浓度依赖性地抑制H2O2、Fe2+以及.OH诱导的肝匀浆和肝线粒体体系的脂质过氧化作用。提示,BRPS具有体外抗脂质过氧化活性。     

祁州漏芦不同溶剂提取物抗氧化活性的比较研究

研究祁州漏芦的体外抗氧化活性。以高铁还原力法检测总抗氧化能力,以水杨酸法检测羟自由基(.OH)清除率,以硫代巴比妥酸(TBA)法测定H2O2和Fe2+诱导的肝匀浆丙二醛(MDA)生成量。结果表明,漏芦不同溶剂提取物均具有较强的总抗氧化能力和清除羟自由基能力,可抑制H2O2和Fe2+诱导的肝匀浆脂质过氧化的发生,且呈剂量依赖性。其中,漏芦正丁醇萃取物(RUBF)的抗氧化活性高于水萃取物(RUAF)。因此,祁州漏芦具有体外抗氧化活性。     

柿子皮提取物的抗氧化活性

为评价柿子皮提取物(persimmon peel extracts,PPE)的抗氧化活性,采用不同的抗氧化评价方法以及Fe2+-H2O2或Fe2+-VC诱导的离体鼠肝线粒体损伤模型。结果显示：PPE具有良好的总抗氧化活性、还原力、脂质过氧化抑制力以及自由基清除能力;清除DPPH自由基、超氧阴离子自由基(O2·)、羟自由基(·OH)的IC50值分别为57、137、425μg/mL;另外,PPE能显著地抑制线粒体脂质过氧化、肿胀、蛋白氧化和ATPase活性降低。说明PPE有明显的体外抗氧化活性,有可能作为一种天然抗氧化剂的新原料。     

花生多肽的体外抗氧化活性研究

通过对红细胞溶血、肝脏与肝线粒体中的脂质过氧化以及肝线粒体肿胀度的测定,结果发现花生多肽能够有效地抑制由羟自由基引起的脂质过氧化,保护生物膜,减少红细胞溶血,减轻肝线粒体肿胀程度,提示花生多肽具有很强的抗氧化能力.     

香水莲花醇提物抗氧化活性的研究

研究了香水莲花醇提物对超氧阴离子自由基、羟自由基的清除作用和对脂质过氧化反应(LPO)的抑制作用,测定了其还原能力及总抗氧化能力。结果表明:香水莲花醇提物对超氧阴离子自由基及羟自由基有清除作用;对脂质过氧化反应有较好的抑制作用;具有较大的还原能力和总抗氧化能力。     

鱼腥藻藻蓝蛋白的抗氧化作用

目的:探讨鱼腥藻藻蓝蛋白(AnabaenaPhycocyaninAPC)的体外抗氧化作用。方法:采用化学比色法测定APC在体外的(1)总抗氧化能力;(2)抑制活性超氧阴离子自由基(O2·)的能力;(3)清除羟自由基(·OH)的能力;(4)在其作用下的小鼠肝组织中脂质过氧化产物丙二醛(MDA)含量的变化。结果:一定浓度范围内不同纯度的APC均有总抗氧化能力,能清除O2·和·OH及抑制MDA的生成,且呈现一定剂量关系。结论:APC在一定浓度范围内具有抗氧化作用。     

沙棘多糖清除自由基及抗脂质过氧化作用研究

目的:探讨沙棘多糖体外清除自由基及抗脂质过氧化作用。方法:采用体外抗氧化活性法测定沙棘多糖对DPPH自由基、羟自由基和超氧阴离子自由基清除能力及沙棘多糖总还原能力;制备5%小鼠肝脏匀浆,通过模拟建立体外小鼠肝匀浆自发性脂质过氧化模型、CCl₄体外诱导小鼠肝匀浆脂质过氧化模型、H₂O₂体外诱导小鼠肝匀浆脂质过氧化模型、Fe2+-V_C 体外诱导小鼠肝脏脂质过氧化模型,利用TBA显色法,观察沙棘多糖对脂质过氧化的抑制作用。结果:沙棘多糖对DPPH自由基、OH自由基和超氧阴离子自由基都具有一定的清除能力,其IC₅₀值分别为1.55、1.23、8.31 mg/mL,其浓度为2 mg/mL时,还原能力稍高于同浓度V_C。沙棘多糖对小鼠肝匀浆自发性脂质过氧化及CCl₄、H₂O₂、Fe2+-V_C所诱导的肝脏脂质过氧化均具有抑制作用,其IC₅₀值分别为1.10、1.59、9.13、1.39 mg/mL。结论:沙棘多糖具有一定的抗氧化活性及抗脂质过氧化作用。     

西瓜籽油的体外抗氧化作用研究

探讨了西瓜籽油体外抗氧化活性。采用三氯乙酸法测定西瓜籽油的还原能力,Fenton反应体系测定西瓜籽油的羟自由基(·OH)清除率,NBT光化还原法测定西瓜籽油的超氧阴离子自由基(O-2·)清除率,硫代巴比妥酸法测定肝匀浆丙二醛(MDA)相对含量以反映西瓜籽油对脂质过氧化的影响,并与BHT的抗氧化活性进行比较。结果表明:西瓜籽油有一定的还原能力,具有显著的清除·OH和O-2·能力;能抑制小鼠肝组织自发性脂质过氧化,当西瓜籽油的质量浓度为10mg/mL时作用达最强。     

猪皮胶原多肽的体外抗氧化特性研究

以猪皮胶原多肽为原料,研究其羟自由基清除能力、还原能力、对Fe2+诱导的脂质过氧化抑制能力以及对猪油氧化的抑制效果,考察其体外抗氧化特性.结果表明:在10mg/mL～50mg/mL浓度范围内,猪皮胶原多肽具有一定的羟自由基清除能力、还原能力和对Fe2+诱导的脂质过氧化抑制能力,且随着浓度的增加抗氧化作用也增强,当浓度为50mg/mL时,对羟自由基的清除率为56.38％,还原力为0.909,对Fe2+诱导的脂质过氧化抑制率为43.34％;不同添加量的猪皮胶原多肽对猪油氧化均有明显的抑制作用,当添加量为2％时,抗氧化效果优于0.02％的叔丁基羟基茴香醚(BHA).猪皮胶原多肽具有一定的体外抗氧化作用.     

莳萝叶精油抗氧化性质的研究

从总抗氧化活性、羟自由基清除能力、DPPH自由基清除能力、超氧阴离子自由基清除能力和抑制卵黄脂质过氧化能力5方面评价了莳萝叶精油(DEO)的抗氧化活性,并将其与合成抗氧化剂PG进行比较,结果发现莳萝叶精油的总抗氧化活性、清除羟自由基和超氧阴离子自由基能力较强,且强于PG,但是其清除DPPH自由基和抑制脂质过氧化的能力不及PG。     

大豆皂甙体外抗氧化活性研究

研究大豆皂甙的抗氧化作用,用分光光度法测定大豆皂甙的总抗氧化能力和抗活性氧能力、肝匀浆丙二醛(MDA)生成量和肝线粒体膨胀程度。结果表明,大豆皂甙的体外总抗氧化能力和抗活性氧能力较强,可抑制肝组织脂质过氧化反应,减轻肝线粒体膨胀程度。提示,大豆皂甙具有体外抗氧化活性。     

草苁蓉体外抗氧化活性研究

研究草苁蓉提取物(BRE)的体外抗氧化作用。用分光光度法测定BRE的总抗氧化能力、抗活性氧能力、丙二醛(MDA)以及过氧化脂质(LOOH)生成量。结果表明,BRE的体外总抗氧化能力和抗活性氧能力较强,可抑制血清和肝组织脂质过氧化反应。结论:BRE具有体外抗氧化活性。     

甘薯叶柄藤类黄酮的体外抗氧化作用研究

研究薯蔓黄酮(FSPV)的体外抗氧化作用。测定了FSPV对二苯代苦味酰自由基(DPPH)、超氧阴离子自由基(O2·)和羟自由基(·OH)的清除率,同时用硫代巴比妥酸(TBA)法测定其对亚油酸的抗氧化性。实验结果表明:FSPV对DPPH的清除效果良好(IC50=8.60mg/L);对O2·清除能力强于芦丁但弱于VC;对·OH的清除能力强于芦丁和VC;对亚油酸也有很好的抗氧化作用。体外实验证实,FSPV具有较强的抗氧化能力。     

A novel method to measure both the reductive and the radical scavenging activity in a linoleic acid model system

The aim of this study was to develop a combined method for measuring the total antioxidant activity, the reductive and the radical scavenging activity. Linoleic acid was used as the substrate for an iron-initiated lipid peroxidation to measure the total antioxidant activity. In addition, methyl esters of linoleic acid hydroperoxides were used as substrates to measure the reductive antioxidant activity. The radical scavenging antioxidant activity was calculated by subtracting the reductive antioxidative activity from the total antioxidative activity. As representative examples, the antioxidants alpha-tocopherol, ascorbic acid, trans-resveratrol and L-glutathione as well as commonly used food additives such as 2(3)-tert-butyl-4-hydroxyanisole (BHA) and 2,6-bis(1,1-dimethylethyl)-4-methylphenol (BHT) were analyzed. The results for the novel antioxidation test showed that alpha-tocopherol, BHA and BHT are primarily acting as radical scavengers, whereas ascorbic acid and L-glutathione show a strong reductive capacity. As linoleic acid as well as its hydroperoxides both are present in foods and in the organism, the test presented here can be considered representative of radical reactions occurring in food matrixes and in vivo. Further experiments are required to document the comprehensive applicability in foods and in vivo.     

色米提取物的抗氧化作用与成分分析研究

为探讨色米提取物总酚含量与抗氧化相关性及其抗氧化的物质基础,以4种不同品种的色米为材料,采用Folin-Ciocalteu法测定总酚含量,三氯化铝比色法测定黄酮含量,DPPH·、ABTS~+·清除法和O~(2-)·清除法评价抗氧化活性,高效液相色谱法进行多酚成分分析。结果表明,4个品种的色米总酚含量范围为42~305.2 mg GAE/g,红米具有最高的总酚和黄酮含量以及最好的抗氧化能力,绿米各项指标均最低。提取物成分分析结果显示,4个品种均具有一定含量的没食子酸、儿茶素、香草酸、咖啡酸和阿魏酸。     

薤白多糖体外抗氧化活性及其对小鼠急性肝损伤的保护作用研究

本文研究了薤白多糖清除各种自由基及其对小鼠急性肝损伤的保护作用。采用浸提、分步醇沉法提取了三种薤白多糖,利用红外光谱初步分析了其结构组成。结果表明：AMP40在清除羟基自由基（?OH）、超氧阴离子自由基（O2-?）等抗氧化评价体系中比AMP60及AMP80具有更强的清除自由基活性,在实验最大浓度时清除率可分别达到40.96%和49.84%;在对小鼠急性化学性肝损伤的保护作用研究中,发现通过预先灌胃200、400和800 mg/kg BW的薤白多糖AMP40,可以抑制肝损伤小鼠血清中谷丙转氨酶（ALT）和谷草转氨酶（AST）活性的升高,同时能使小鼠肝脏中SOD活性、CAT活性、GSH活性以及T-AOC水平显著增加,而MDA含量显著减少（P<0.05或P<0.01）,且这种变化对AMP40呈现一定的剂量依赖关系,表明AMP40具有一定的肝保护作用。研究表明了薤白多糖的抗氧化活性与其分子量大小及糖醛酸含量密切相关。     

Evaluation of antioxidative performance of tomato extracts obtained by different methods

BACKGROUND: Two extraction methods employing tetrahydrofuran and phosphate buffer (pH 7.4) respectively were used to process tomatoes. The antioxidant contents and antioxidative properties of extracts of four tomato cultivars were measured. To evaluate the overall antioxidative capacity of the tomato extracts, an antioxidative performance index (API) was used, defined as the average of four antioxidative assays, i.e. relative reducing power, ferrous ion‐chelating ability, 2,2‐diphenyl‐1‐picrylhydrazyl free radical‐scavenging activity and superoxide radical‐scavenging activity. RESULTS: A linear correlation between the total antioxidant content (TAC) and API of tomato extracts was found that was independent of the extraction method and tomato cultivar. CONCLUSION: The concept of representing multiple antioxidant activities by a single index is useful for evaluating the overall antioxidative capacity of antioxidants in tomatoes. Copyright © 2007 Society of Chemical Industry     

Evaluation of the phenolic contents and antioxidant capacities of two Malaysian floral honeys

The antioxidant activity of two selected Malaysian honeys, as well as their ethyl acetate extracts, were evaluated. The antioxidant activities were determined in terms of their anti radical power (ARP) as assessed by DPPH radical scavenging assay and their total antioxidant power (TAP), as assessed by FRAP assay. Total phenolic content of the extracts was determined according to the Folin-Ciocalteau procedure. The characteristic antioxidant activities showed a marked correlation with the total phenolic contents. These results indicated that honey has antioxidative and radical scavenging properties, which are mainly due to its phenolic content. This is the first report of the antioxidant properties of Malaysian honeys.     

Antioxidant Potential of Different Dill (Anethum Graveolens L.) Leaf Extracts

Dill (Anethum graveolens L.) have been extensively used in salads, soups, and pickles for its aromatic odor and flavor. Recently, interest in plant-derived food additives has grown. In this study, the possible antioxidant properties of water, ethanol, and acetone extracts of dill leaves were investigated. In order to evaluate antioxidant activities of all extracts, different antioxidant tests were used, such as total antioxidant activity by ferric thiocyanate method, reducing power, DPPH (1,1-diphenyl-2-picryl-hydrazyl) free radical scavenging, hydrogen peroxide scavenging, and ferrous ions chelating activities. The content of phenolic compounds was also determined to be the gallic acid equivalent. Among the three extracts, the water extract of dill leaf showed the most potent antioxidative capacity in each assay, showing 79.66% (at 1 mg/mL) in the DPPH^? radical scavenging activity, 63% (at 800 μg/mL) in the metal chelating effect, 60% (at 400 μg/mL) in the H₂O₂ scavenging activity, and 0.61 absorbance (at 1 mg/mL) in the reducing power.     

基于Plackett-Burman设计和响应面法优化羊肝抗氧化肽的制备工艺

以羊肝为原料,分别测定5种蛋白酶酶切羊肝所得的酶解液的羟基自由基清除率和肽得率。结果表明,风味蛋白酶羟自由基清除率（84.50%）和肽得率（22.49%）最好。在单因素试验基础上,以羟基自由基清除率为评价指标,采用响应面法优化最佳酶解条件。结果表明,羊肝抗氧化肽制备的最佳酶解条件为料液比1∶3（g∶mL）、加酶量2 400 U/g、酶解温度50 ℃、pH7.50、酶解时间2.8 h。在此优化条件下,测得实际羟自由基清除率为93.70%,与模型理论值相接近。羊肝酶解产物中总氨基酸含量为57.23 g/100 g,其中疏水性氨基酸和必需氨基酸占总氨基酸含量分别为46.47%和41.63%,表明以风味蛋白酶酶解羊肝产物具有较高的抗氧化活性和营养价值。