沙棘籽原花色素与葡萄籽原花青素抗氧化活性的比较

采用DPPH·、O2^-、和HO·的清除试验及卵磷脂脂质体氧化试验，研究比较了沙棘籽原花色素和葡萄籽原花青素的抗氧化活性。结果表明：两种原花色素对DPPH·、O2^-·和HO·均具有较强的清除能力；沙棘籽原花色素对O2^-的清除速率和清除活力及对HO·的清除活力显著高于葡萄籽原花青素，对O2^-的半清除浓度分别为23．95μg／mL，与HO·反应的速率常数分别为1．355×10^9L／g·s。两种原花色素均可显著延长AAPH诱导的卵磷脂脂质体氧化的延迟期时间、降低延迟期和扩增期氧化速率，沙棘籽原花色素抑制氧化的效果强于葡萄籽原花青素。     

沙棘籽中原花色素的提取工艺研究

本文以脱脂沙棘籽为原料，乙醇为提取液，通过提取温度、提取时间、脱脂时间、料液比、酒精浓度、pH值6个单因素实验，在中心组合实验基础上，采用响应面分析法，确定沙棘籽中原花色素的最优提取条件。研究结果表明，在提取温度21℃、pH5．1、酒精浓度65％时，沙棘籽中原花色素的提取率达5．84％(以脱脂沙棘干重计)，粗品纯度达39．18％。     

沙棘籽原花色素组成和结构的研究

采用高效液相色谱-电喷雾串联质谱技术分析鉴定沙棘籽原花色素单体和寡聚体组分,采用Sephadex LH-20柱色谱按聚合度大小对沙棘籽多聚体组分进行分级,并通过苄硫醇酸降解反应(简称硫解)对各分级组分的组成结构特征进行分析.共检测到4种单体和8种二聚体:4种单体分别为儿茶素、表儿茶素、棓儿茶素和表棓儿茶素;二聚体包括3种原花青素二聚体、1种原飞燕草素二聚体和4种混合二聚体.并根据ESI提供的质谱信息,分析确定了混合二聚体组成单元的连接顺序.棓儿茶素是构成多聚体各分级组分末端单元的主要组成成分,棓儿茶素和表棓儿茶素(合并计算)是构成各分级组分延伸单元的主要组成成分;平均聚合度为9.1、13.2和17.0,原飞燕草素比例为69.2%、84.6%、87.4%的三个分级组分是多聚体的主要成分,占多聚体总量的74.7%.     

沙棘籽原花青素体外抗氧化活性研究

研究沙棘籽原花青素(SBSPC)体外抗氧化的作用。采用水杨酸法检测沙棘籽原花青素对羟自由基(·OH)的清除作用,用硫代巴比妥酸法测定小鼠肝丙二醛(MDA)的含量,用分光光度法测定小鼠红细胞溶血和肝线粒体肿胀程度,研究SBSPC的抗氧化效果。结果表明:SBSPC可以清除·OH,抑制·OH所致的丙二醛的产生,减少·O H所致的红细胞溶血,降低·OH所致线粒体肿胀程度,证明S B S P C具有抗·O H所致的氧化的作用。     

石榴籽原花色素提取新工艺及其结构鉴定研究

为了优化石榴籽原花色素的提取工艺,以乙醇为提取液,通过单因素试验,研究乙醇浓度、提取时间、液料比、六偏磷酸钠(SH)添加量及提取温度等因素对原花色素得率的影响,并通过二次正交旋转组合设计试验,优化原花色素的提取条件。结果表明,影响原花色素得率的主要因素及其顺序是:提取时间、SH添加量和乙醇体积分数;最佳工艺参数为提取时间87 min、SH添加量0.13%和乙醇体积分数60%,在此优化条件下原花色素得率为8.58%。经红外光谱分析,初步推测石榴籽原花色素是以原花色素定为主要结构单元的聚合物,原翠雀定含量较少。     

沙棘籽粕原花青素制备、体外抗氧化及细胞活力评价

本实验优化了沙棘籽粕原花青素的提取方法,条件为80%乙醇,提取温度35℃,液料比8∶1 m L/g,时间1.5 h,p H3.0,在该条件下的原花青素提取率为（97.31±0.48）mg/g沙棘籽粕;对提取得到的原花青素提取物进行了DPPH自由基和羟自由基清除能力实验,并分析得到IC₅0,发现沙棘籽粕原花青素提取物的DPPH自由基清除能力较维生素C强;羟自由基清除能力较弱;MTT法测定了沙棘籽粕原花青素提取物对小鼠B16黑色素瘤细胞活力的抑制作用,分析得到24、48、72 h处理时间下提取物IC₅0分别为542.78、199.25、82.58μg/m L。结论:沙棘籽粕提取物对小鼠B16黑色素瘤细胞具有一定的抑制作用,随着剂量和时间的增加,呈逐渐增强的趋势。      

沙棘籽粕原花青素的提取工艺研究

本文以沙棘籽粕为原料,以乙醇-水溶液为提取剂,通过5个单因素试验探讨对原花青素提取效果的影响,在此基础上选取4个因素经正交试验优化得到最佳提取工艺参数为：粉碎度80目、乙醇浓度70%、料液比1∶12、提取温度50℃、提取时间4h。在此条件下测得产品中的原花青素含量为27.20%,提取率为73.85%。     

原花色素抗氧化生物活性研究进展

该文综述原花色素的结构、化学特性,抗氧化机制及抗氧化生物活性方面研究,如预防心血管疾病、保护肝脏、抗肿瘤、抗过敏及抗炎、防辐射等作用,为其在功能性食品、药物、化妆品等领域深入研究和开发提供参考。     

杨梅叶原花色素对猪油抗氧化作用的研究

以过氧化值(POV)、酸价(AV)、丙二醛含量为指标,采用Schaal烘箱法研究了杨梅叶原花色素对猪油的抗氧化作用,并用食品氧化稳定性测定仪测定氧化诱导期(IP)。结果表明:杨梅叶原花色素对猪油过氧化值、酸价、丙二醛含量的升高具有显著的抑制作用(p<0.05),能抑制猪油的氧化。当杨梅叶原花色素添加量为0.1%时,其对猪油氧化的抑制作用强于BHT,但比TBHQ稍弱,表明杨梅叶原花色素对猪油具有良好的抗氧化效果,能有效延缓猪油的氧化程度。在第14 d时,相比空白组,杨梅叶原花色素添加量为0.1%的处理组对猪油过氧化值、酸价、丙二醛含量的抑制率分别为76%、69%、94%。此外,随着杨梅叶原花色素添加量的增加,猪油的氧化诱导期增加,杨梅叶原花色素添加量达到0.1%时其氧化诱导期和抗氧化系数介于BHT和TBHQ之间,且与BHT无显著性差异(p>0.05),说明杨梅叶原花色素对猪油具有抗氧化作用。      

沙棘籽粕原花青素提取纯化工艺研究

对沙棘籽粕原花青素的提取工艺进行了研究。结果表明:以水作为提取溶剂,最佳提取工艺条件为料液比1∶10,提取温度50℃,提取时间1 h;静态和动态吸附解吸试验表明,AB-8大孔吸附树脂对沙棘籽粕原花青素有较好的吸附解吸能力,60%乙醇洗脱液经浓缩至干后原花青素含量为78.32%。     

葡萄籽中原花青素的稳定性研究

研究了原花青素在不同条件下的稳定性，结果表明：原花青素光稳定性较差；低pH值稳定性较好；热稳定性较好，但在60℃以上温度时原花青素会受到一定影响；添加剂Vc、亚硫酸氢钠可提高葡萄籽原花青素的稳定性；Fe^2＋和Sn^2＋对原花青素有明显的破坏作用，Cu^2＋、Pb^2＋、Mn^2＋影响较小，Al^3＋、Zn^2＋、Na^＋、Mg^2＋影响较大。     

石榴籽丙酮提取物抗氧化活性研究

研究了石榴籽丙酮提取物的抗氧化活性及清除自由基的能力。采用Schaal烘箱法测定对菜籽油过氧化值(POV)的影响,比色法测定其在卵黄脂蛋白不饱和脂肪酸过氧体系中的抗氧化活性,以及用Marklund法和邻二氮菲-Fe2 氧化法测定其对O2-·和·OH自由基的清除能力。结果表明:石榴籽丙酮提取物对菜籽油和卵黄脂蛋白不饱和脂肪酸过氧体系均有较强的抗氧化性能,并具有一定的清除O2-·和·OH自由基的能力。     

ANTIOXIDATIVE EFFECTS OF POLYPHENOLS FROM LEAVES OF ARTEMISIA PRINCEPS PAMP. ON LIPID PEROXIDATION IN VITRO

The leaves of Artemisia princeps Pamp. have been used for tea and food in Japan. The antioxidative effects of polyphenols in the leaves of A. princeps on lipid peroxidation (LPO) by free radicals in vitro were investigated. The total polyphenol content in the leaves was 4.58%. The condensed tannin content in the leaves was 0.62% by vanillin assay and 0.14% by proanthocyanidin assay. The polyphenols inhibited LPO of erythrocytes by hydrogen peroxide (H₂O₂) and lecithin peroxidation by the interaction of hemoglobin and H₂O₂. These results support the thesis that the leaves of A. princeps are useful teas and foods that function against oxidative stress such as LPO.     

陕北糯高梁米糠中原花青素的提取工艺研究

对我国陕北糯高粱米糠中原花青素提取工艺进行研究.通过正交试验对提取工艺进行优化.结果表明,超声波提取糯高粱米糠原花青素的最佳工艺条件为:乙醇浓度50%,提取温度50℃,提取时间25 min,料液比1:40.并对提取物进行纯化.产品纯度为83.4%.     

葡萄籽原花青素的提取和检测方法

对原花青素的概念、测定方法及其存在的问题进行了分析，综述了原花青素的性质，安全性和提取、检测方法，并对统一的原花青素检测方法进行了展望。     

INHIBITORY EFFECT OF ANTHOCYANIN EXTRACT FROM SEED COAT OF BLACK BEAN ON PERICARP BROWNING AND LIPID PEROXIDATION OF LITCHI FRUIT DURING STORAGE

ABSTRACT

Anthocyanins were extracted from seed coats of black beans (Glycine max[L.]) and the inhibitory effects of anthocyanin extract on pericarp browning and lipid peroxidation of litchi fruit were investigated. Litchi fruit were infiltrated for 3 min with 0 (control) or 50 mg/L of anthocyanin extract at a reduced pressure of 53 kPa, then packed in 0.03 mm thick polyethylene bags, and finally stored at 28C for 6 days. Changes in browning index, contents of anthocyanins and total phenol, peroxidase (POD) activity, levels of relative leakage rate and lipid peroxidation, α,α‐diphenyl‐β‐picrylhydrazy (DPPH) radical scavenging activity and reducing power were evaluated. Application of anthocyanin extract from black bean delayed pericarp browning of litchi fruit during storage, which was associated with reduced POD activity and higher contents of anthocyanins and total phenol. Moreover, the anthocyanin extract was found to have a direct inhibition on the POD activity in vitro. Furthermore, application of the anthocyanin extract apparently reduced lipid peroxidation and relatively maintained membrane integrity, which may account for browning inhibition to an extent. Finally, higher DPPH radical scavenging activity and reducing power of the fruits treated with the anthocyanin extract than control fruits possibly benefited in scavenging free radicals and reducing lipid peroxidation. It is, therefore, suggested that inhibited POD activity and reduced lipid peroxidation by the anthocyanin extract from seed coats of black beans were responsible for the inhibition of pericarp browning of litchi fruits.

PRACTICAL APPLICATIONS

Lipid peroxidation is a major cause of quality deterioration of postharvest fruits and vegetables. Some synthetic antioxidants are beneficial in inhibiting lipid peroxidation. However, considering that synthetic antioxidants, such as butylhydroxyanisole and butylated hydroxytoluene (BHT), have potential toxicity, the use of natural extracts to extend the shelf life of postharvest fruits and vegetables is a tendency. In our previous study, it has been found that anthocyanin extract from litchi pericarp has stronger antioxidant activities or free radical scavenging activities than BHT and ascorbic acid ( Duan et al. 2007 ). In this study, the application of anthocyanin extract from seed coat of black soybean showed reduced lipid peroxidation and pericarp browning. It could be used potentially as a postharvest technology for reducing or replacing the use of other chemicals, but it requires further investigation.     

淡竹叶总黄酮最佳萃取工艺及其抗氧化性的研究

研究淡竹叶中总黄酮最佳萃取工艺条件,并对淡竹叶提取物进行抗氧化性测定研究。结果显示：乙醇萃取法最佳工艺条件为乙醇体积分数70％,提取时间60min,固液比1g：20mL,提取温度80℃;提取率可达1．84％。抗氧化性研究表明,淡竹叶中黄酮类化合物有良好的抗氧化性,其抗氧化能力随浓度增大而增强。     

溪黄草提取物成分预试及对猪油的抗氧化作用研究

用水、95％乙醇和石油醚对溪黄草进行提取，根据颜色反应及沉淀反应初步判断所含化学成分的类型，研究各提取物对猪油的抗氧化作用。结果表明：溪黄草水提取物具有一定的抗猪油自动氧化能力，且作用强于抗坏血酸，而95％乙醇和石油醚提取物对猪油的抗氧化作用不明显。     

EFFECTS OF PRODUCTS FROM SEEDLESS AND SEEDED HOPS ON BEER QUALITY

Comparative semi-industrial brewing trials with standard Continental lager beers have been carried out in Switzerland using hop pellets and hop extracts made from seeded and seedless hops. It has been demonstrated that the products from seeded hops containing 8% and 9% of seeds have no adverse effect on beer quality and that the flavour of all the beers was acceptable.