Extraction of Pumpkin Polysaccharide by Complex Enzyme Method and Its Antioxidant Research

[Objective] This paper aims to study a new method of extracting pumpkin polysaccharide from pumpkin. Single factor experiments were conducted to examine the effects of extracting time,temperature,the solid-liquid ratio and pH value on the extraction yield of polysaccharide from pumpkin. [Method] The best enzyme ratio and extraction conditions for complex enzymes extraction were determined through orthogonal tests. Scavenging ·OH and O-2 activities of pumpkin polysaccharides were also investigated by salicylic acid and improved self-oxidation of o-pheno methods respectively. [Results] The results showed that the biggest extraction yield of polysaccharide from pumpkin can be got when adding 1% cellulose enzyme,1.5% pectinase,1.0% papain and Na2HPO4-citric acid buffer solution (pH was 4.6),and oscillating for 30 min under water at 40 ℃ with the solid-liquid ratio of 1:30. In addition,pumpkin polysaccharides had a strong activity of eliminating ·OH,but very weak activity to scavenge O-2. [Conclusion] This study provided basic data for research and application of Pumpkin polysaccharide.

Pomegranate （Punica granatum L.） Peel Extract as a Source of Natural Antioxidant

An increase in the demand for natural additives has shifted the attention from synthetic to natural antioxidants. Antioxidative components from pomegranate peel were extracted by using different solvents like methanol, ethanol, acetone, chloroform and ethyl acetate. All the extracts were tested for Total phenolic content （TPC） and the methanol which proved to be best in extracting the phenolic compounds was used to assess the antioxidant property by using different methods like Diphenyl piridyl picryl hydrazyl （DPPH）, Relative reducing power （RRP）, Beta carotene bleaching and Ferric thiocyanate （FTC）. The antioxidant activity （AA） of pomegranate peel extract （PPE） was compared with Butylated hydroxyl toluene （BHT） and Butylated hydroxyl anisole （BHA）. The methanolic extract was examined by Liquid Chromatography and Mass Spectroscopy （LCMS） and the spectra showed the presence of different phenolic compounds. The extracts were tested for their efficiency in preventing rancidity of Refined Bleached Deodorized Soybean oil （RBDSBO） in comparison with BHT and control at 200 ppm concentration. The PPE proved to be best in preventing rancidity. Owing to the present results, the studies can further be extended to exploit the PPE for application into different food products.

Oxidative Stress and Role of Natural Plant Derived Antioxidants in Animal Reproduction

The experimental knowledge on the role of oxidative stress,and beneficial and detrimental effects of plant derived antioxidants in male and female animal reproduction are reviewed in this article.Free radical-induced oxidative stress in animal reproduction causes great loss to livestock industry.Antioxidant therapy has been implicated to be effective in preventing diseases resulted from oxidative stress.Considering the advantages of lower side effects of natural antioxidants than those of synthetic antioxidants,plants or their extracts have been extensively utilized in animals.Although many advances have been gained on application of plant derived antioxidants in alleviating oxidative stress,debatable issues still exist.Because many opposite effects were observed even using plant extracts containing similar bioactive substances in the same animal species.Therefore,plant derived antioxidants,like free radicals,are ＂double-edged swords＂ in animal reproduction,representing that they may exhibit beneficial or detrimental effects in animal reproduction,including spermatogenesis,semen functions,estrous cycles,ovulation,ovary functions,endometrium,embryo development,and pregnancy.Besides dose-dependent manner as an explanation of plant extracts＇ dual function,future studies are needed to investigate the mechanism of double-edged actions of plant derived antioxidants in different animal reproduction systems.

GC-MS Analysis of Low-polar Components and Antioxidant Activities of Vernonia divergens

[Objective]This study aimed to analyze the low-polar components and antioxidant activities of Vernonia divergens.[Method]After extraction,the relative contents of various components were calculated with peak area normalization method.In addition,V.divergens were extracted with n-hexane,ethyl acetate and n-butanol,respectively;DPPH scavenging capacity and reducing capacity of these three extracts were analyzed and compared with that of vitamin C.[Result]A total of 29 compounds were identified that accounted for 88.30%of the total amount of low-polar chemical components.The results indicated that n-butanol extract exhibited higher DPPH scavenging capacity and reducing capacity than ethyl acetate extract and n-hexane extract.[Conclusion]This study provided a theoretical basis for the development and utilization of V.divergens.

Effects of Dietary Picria felterrae Lour Extracts on Serum Biochemical Indexes and Immune Function of Guangxi Partridge Chickens

[Objective] This trial was to investigate the effect of dietary Picria felterrae Lour extracts on serum biochemical indexes and immune function of Guangxi Partridge chickens. [Method] Totally 500 individuals of 1-day-old Guangxi Partridge chickens were randomly divided into five groups, five replicates each group and 20 chicks each replicate. Groups A, B and C were treatment groups supplemented with 0.70%, 0.35% and0.175% P. felterrae extracts in the basal diet, respectively; group D was a medical control group supplemented with 0.01% colistin sulfate premix in the basal diet; and group E was a control group with basal diet. Serum samples were collected from 10 chickens in each group at 21, 35 and 49 days of age, to analyze the biochemical and immune indexes. [Result] It had no significant impact on serum TP and GLU contents of chickens by adding different levels of P. felterrae extracts in the basal diet（P 〉0.05）. However, at 21 and 35 days of age, the TBILI content of chickens in groups A, B and C were extremely lower or significantly lower than that in group E（ P〈0.01; P〈0.05）. At 35 days of age, the serum AKP activities in groups A, B and C were extremely higher than that in group E（P〈0.01）, and the serum GOT activities at 21 and 35 days of age in group C were significantly higher than that in group E（P〈0.05）. At 49 days of age, the serum Ig G content in groups A, B and C and the IL-2 content in group B and group C were significantly lower or extremely lower than that in group E（ P〈0.05; P〈0.01）; the T-AOC content in group B was significantly higher than that in group E（P〈0.05）; the GSH content in groups A, B and C were significantly higher than that in group E（ P〈0.05）. Adding different levels of P. felterrae extracts in the diet significantly decreased the TBILI content, reduced the Ig G, IL-2 and IL-6 contents, and improved the AKP and GOT activities and the T-AOC and GSH contents of Guangxi Partridge chicken. [Conclusion] Adding 0.35% P. felterrae extracts in the basal diet received the best effort.

闪式提取无花果叶总黄酮及其抗氧化活性研究

试验旨在研究闪式提取无花果叶总黄酮及其抗氧化活性。试验以无花果叶为原料,使用闪氏提取方法,以乙醇为溶剂,分别以提取时间、乙醇体积分数和液料比为单因素,测定在相应条件下总黄酮的最佳提取率,在此基础上利用响应面法对提取工艺进行优化。结果显示,响应面优化的提取工艺参数为提取时间87 s、乙醇体积分数67%、液料比87 mL/g。在此条件下,实际总黄酮提取率为3.43%,与预测值3.41%基本一致。无花果叶总黄酮对1,1-二苯基-2-三硝基苯肼(DPPH)自由基、超氧阴离子自由基、羟自由基均有良好的清除能力,IC50值分别为0.019、0.017、0.076 g/L。研究表明,无花果叶总黄酮在体外具有良好的抗氧化能力。

牡蛎抗氧化寡肽的提取分离研究

目的:研究牡蛎所含有机质的成分及活性。方法:以牡蛎壳粉为原料,水煎提取有机质,通过双缩脲法进行定性分析和含量测定,再通过阴离子交换层析和反向C8柱层析分离,得到牡蛎壳寡肽产品,并进行抗氧化性能考察。结果:牡蛎有机质提取物主要为寡肽类成分,总肽含量约为38.02%,产物具有较强的清除DPPH·自由基和超氧阴离子自由基的能力。结论:牡蛎壳寡肽是具有良好开发前景的抗氧化活性物质。

红景天提取物对凡纳滨对虾抗氧化系统及抗低盐度胁迫的影响

为研究红景天(Rhodiola rosea)提取物对凡纳滨对虾(Litopenaeus vannamei)抗氧化系统及抵抗低盐度胁迫的影响,该实验设计0 mg·kg^(-1)、300 mg·kg^(-1)、1 000 mg·kg^(-1)和3 000 mg·kg^(-1) 4个红景天提取物水平饵料添加量,饲喂凡纳滨对虾28 d。然后进行72 h低盐度(10)胁迫实验,测试凡纳滨对虾肝胰腺总抗氧化能力(T-AOC)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)活性及GSH-Px、CAT基因表达水平。结果显示,在天然海水养殖条件下,GSH-Px、CAT活性和GSH-Px基因表达水平在某些时段被显著诱导(P<0.05)。低盐度胁迫24 h,对照组抗氧化指标相比于其他各组的变化幅度最大。低盐度胁迫72 h,红景天组T-AOC、CAT活性和GSH-Px、CAT基因表达水平均显著高于对照组(P<0.05)。双因素方差分析结果显示红景天提取物添加量与时间的交互效应对抗氧化指标的影响显著。结果表明,红景天提取物能够有效缓解胁迫初期凡纳滨对虾抗氧化指标的剧烈改变,明显提高胁迫后期机体的抗氧化系统功能,具有成为抗应激饲料添加剂的潜力。

桑白皮多糖提取工艺研究及抗氧化活性评价

研究桑白皮多糖提取工艺并评价其抗氧化活性,以期为其开发应用提供参考依据和理论支撑。采用超声辅助提取桑白皮多糖,设计正交试验对提取条件进行优化,用硫酸苯酚法测定总糖含量,3,5-二硝基水杨酸(DNS)比色法测定还原糖含量,两者之差表示多糖含量。采用1,1-二苯基-2-三硝基苯肼(DPPH)比色法、羟基自由基(·OH)清除法、超氧阴离子(·O-2)清除法研究其抗氧化活性。桑白皮多糖的最佳提取条件为料液比1∶20,超声时间30min,提取温度50℃,提取2次。桑白皮多糖对DPPH和·OH清除作用与质量浓度剂量相关,以维生素C(Vc)作为阳性对照,结果显示桑白皮多糖对DPPH自由基和·OH具有一定的抗氧化活性。发现桑白皮多糖对邻苯三酚自氧化产生的超氧阴离子促luminol发光体系具有增敏作用。进一步研究发现该增敏作用与多糖质量浓度成线性相关。桑白皮多糖具有一定抗氧化性但不及Vc,桑白皮多糖对邻苯三酚自氧化体系的增敏作用具有特异性,该发现具有潜在应用价值。

迷迭香提取物的抗氧化特性及应用中存在的问题

迷迭香提取物作为一种安全、高效的天然抗氧化剂,已广泛应用于食品中。本文对迷迭香提取物的主要抗氧化成分、抗氧化特性及其在应用中存在的问题进行了综述,并对其发展前景进行了展望。

人参根中黄酮类化合物提取及其抗氧化性研究

目的提取人参根总黄酮并研究其体内外抗氧化活性。方法采用乙醇回流和聚酰胺富集法提取人参根总黄酮;通过DPPH法、Fenton法和大鼠饲喂实验研究人参根总黄酮的抗氧化能力。结果当人参根总黄酮质量浓度为0.5 mg/mL以上时,对DPPH自由基的清除率超过80%;0.6 mg/mL时,对羟自由基清除率可达70.8%;80～120mg/(kg.d)持续饲喂5周能使大鼠脑SOD活性提高17.97%以上。结论人参根总黄酮在体外对DPPH自由基和羟自由基具有较强清除作用,体内对SD大鼠脑组织中SOD活性亦有增强作用。

芒果叶不同极性部位提取物的抗氧化活性

对芒果叶不同极性部位提取物的抗氧化活性进行研究。用DPPH法考察最优反应条件,综合评价其抗氧化活性,测定其黄酮含量,以IC50值作为评价清除DPPH自由基能力的指标,用芒果苷和抗坏血酸作为对照品进行自由基清除率的比较。试验结果表明:芒果叶石油醚、乙酸乙酯、正丁醇萃取物及水部位提取物的黄酮含量依次为:(33.616±3.208)、(292.063±1.100)、(180.469±2.067)、(21.717±1.157)mg/g,IC50值分别为:102.877、9.014、19.494、221.784μg/mL。由此可以看出,芒果叶各类提取物均具有一定的抗氧化活性,其中乙酸乙酯萃取物抗氧化活性最强,其次为正丁醇、石油醚,最后为水部位提取物。相关性分析结果表明,芒果叶各极性部位提取物的黄酮含量与清除DPPH自由基的能力呈负相关,芒果叶各部位提取物的黄酮含量是影响其抗氧化活性的主要因素。

核桃花粉提取物的抗氧化性研究

以甲醇、乙醇、水为溶剂提取西林2、西林3、西扶2、西洛3和香玲等5个核桃品种花粉的活性成分,通过测定不同溶剂提取物的总酚含量、还原能力、DPPH自由基清除能力和抗脂质氧化能力评价核桃花粉的抗氧化活性。结果表明:核桃花粉提取物的还原能力与提取物中的总酚含量呈正相关,顺序为:甲醇提取物>乙醇提取物>水提取物;对DPPH自由基的清除作用大小为:乙醇提取物>甲醇提取物>水提取物;5种花粉的水提取物抗脂质氧化能力较强;西林2的还原能力和清除DPPH自由基的能力最强;西林3水提物的抗脂质氧化活性最好。

葡萄籽中多酚物质的超声提取及其抗氧化活性研究

[目的]研究葡萄籽多酚的超声波提取条件和抗氧化活性。[方法]以超声提取获得葡萄籽多酚,采用Fenton反应.OH体系研究抗氧化活性。[结果]最佳提取工艺条件为:超声提取60 min,浓度75%乙醇,料液比为1∶20。在最佳条件下,多酚得率为10.71%。葡萄籽多酚提取物对Fenton反应羟自由基清除的IC50为0.031 g/L,0.093 g/L时清除率达最大,最大清除率为87.12%。[结论]葡萄籽多酚超声提取具有良好的抗氧化活性。

超声波辅助提取葛根中总黄酮及其体外抗氧化性的研究

利用超声波辅助乙醇浸提法探索提取葛根中总黄酮的最佳条件,并进一步考察葛根总黄酮提取物的体外抗氧化性。结果表明,葛根中总黄酮最佳提取工艺为:温度60℃,提取固液比为1∶15(g/m L),70%体积分数的乙醇溶液,提取25 min。在此条件下,葛根中总黄酮的提取率可达2.91 mg/g。葛根黄酮提取物对DPPH·、羟基自由基有明显的清除作用。

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。

茄蒂黄酮提取工艺及抗氧化性研究

目的研究茄蒂黄酮提取工艺及体外抗氧化能力。方法在料液比、乙醇浓度和超声时间三个单因素实验基础上,利用Box-Behnken设计模型,研究三个自变量对茄蒂黄酮产量的影响。采用邻二氮菲-Fe2+-H2O2氧化法、邻苯三酚自氧化法、二苯基苦味酰基苯肼自由基体系、还原力实验进行抗氧化活性测定。结果提取最佳条件为:料液比1∶26(g/mL),乙醇质量分数73%,超声时间30 min。在此条件下黄酮产量为37.09 mg/g。其清除.OH、O2-.、DPPH.的IC50值分别为0.47、0.58、0.068 mg/mL,还原力的IC0.5值为0.60 mg/mL。相比之下提取液对DPPH.清除作用最为显著。结论茄蒂黄酮提取物具有较强的抗氧化活性。

鄂西北产猫眼草提取物体外抗氧化性及光稳定性测试

猫眼草为鄂西北地区常见的野生有毒植物种,经测定具有较强的杀虫、抑菌活性。为了深入开发此植物资源,室内测定其提取物的体外抗氧化性及光稳定性。采用α-脱氧核糖法、邻苯三酚自氧化法、DPPH自由基清除法和铁氰化钾还原法等方法体外评价猫眼草提取物的抗氧化性。同时,采用高效液相色谱法测定其光稳定性。结果表明:①随着猫眼草提取物质量浓度的升高,羟自由基、氧自由基、DPPH自由基的清除率上升,分别高达82.04%、87.99%、87.73%。在一定范围内,随着猫眼草提取物质量浓度的升高,对铁氰化钾的还原能力也在升高。②猫眼草提取物的光稳定性较差,Tween-20(表面活性剂)和水杨酸苯酯(光稳定剂)对其具有一定的光稳定增效作用。

天山堇菜提取物抗氧化性的研究

用Na_2S_2O_3-I_2滴定法测定了天山堇菜提取物对猪油的抗氧化作用。结果表明,不同溶剂天山堇菜提取物对油脂均有一定的抗氧化性,强弱顺序是:85%的乙醇提取物的抗氧化活性>丙酮提取物>氯仿提取物>乙酸乙酯提取物>无水甲醇提取物>正己烷提取物,且提取物用量与抗氧化性呈正相关系。同时与VE和VC进行比较,0.5%(W/V)的85%乙醇提取物的抗氧化性强于0.02%(W/V)VC,而0.02%(W/V)VE的抗氧化活性很小。

玉米黄色素提取工艺及其抗氧化活性研究

以玉米糁为原料,通过单因素和正交试验,考察浸提温度、浸提时间、乙醇体积分数、液料比对提取液中玉米黄色素含量的影响,并研究了玉米黄色素在不同体系下的抗氧化活性。结果表明,玉米黄色素最佳提取工艺为:浸提温度70℃,浸提时间3 h,乙醇体积分数为80%,液料比10:1。玉米黄色素对DPPH·、超氧阴离子自由基以及羟基自由基均有清除作用,并且其对DPPH·和羟基自由基的清除效果优于BHT。当样品质量浓度小于9.0μg/mL时,玉米黄色素对超氧阴离子自由基的清除作用高于BHT。当样品质量浓度在9.0～15.0μg/mL范围内时,玉米黄色素对超氧阴离子自由基的清除作用与BHT基本一致。此外,玉米黄色素有较强的还原力,对三价铁离子的还原能力高于BHT。玉米黄色素能够抑制亚油酸过氧化,但其抗氧化作用低于BHT。