甘草甜素与甘草苷的提取分离与结构鉴定

以乌拉尔甘草为原料,用70%乙醇提取,大孔吸附树脂粗分离,SephadexLH-20和聚酰胺进一步纯化,得到二个单体物质,经核磁共振法鉴定,分别为甘草甜素A和甘草苷。     

解郁胶囊中甘草提取纯化工艺研究

目的优选解郁胶囊中甘草的最佳提取、纯化工艺条件。方法采用高效液相色谱法测定甘草苷、甘草酸含量,以乙醇体积分数、乙醇用量、提取时间为考察因素,以甘草苷、甘草酸提取率和浸膏得率的综合评分为指标,采用正交试验法优选甘草提取工艺;以比吸附量和洗脱率为指标,采用大孔吸附树脂法纯化。结果优选提取工艺条件为50%乙醇,10倍量,提取2次,每次2 h;纯化工艺条件为选用D101型大孔吸附树脂,上样溶液质量浓度为0.2 g/m L,最大上样体积为2.5 BV(BV为树脂体积),以70%乙醇3倍树脂体积洗脱。结论优选的提取、纯化工艺条件提取甘草有效成分,提取率高,工艺合理可行。     

竹叶花椒中总黄酮提取及富集试验研究

采用微波辅助提取法,通过单因素和正交试验优化提取条件,利用聚酰胺-大孔吸附树脂联用法富集纯化提取样品中的总黄酮,研究竹叶花椒中总黄酮的提取和富集纯化工艺。试验确定最佳提取工艺参数为乙醇浓度60%,料液比1∶30（g/mL）,微波功率400 W,提取温度80℃,提取时间25 min,总黄酮得率达到9.20%。以60%乙醇为洗脱液,聚酰胺-大孔吸附树脂联合吸附纯化总黄酮收率和纯度分别为43.50%和42.54%,效果优于单独使用吸附剂。     

甘草查尔酮B的合成

对药食同源甘草中具有保健功能的查尔酮化合物甘草查尔酮B的合成进行研究。以2,3,4-三羟基苯甲醛为原料,用氯甲基乙基保护醛基对位和间位羟基,再用甲基保护邻位羟基和四氢吡喃保护的对羟基苯乙酮在氢氧化钙催化下发生Claisen-Schmidt缩合,最后用氯化氢乙醇溶液脱去保护基得到甘草查尔酮B。考察了溶剂和碱对Claisen-Schmidt缩合反应的影响,确定了乙醇和水等比例混合为最佳溶剂,氢氧化钙为最佳碱。总收率为17.1%,产品的结构经红外、核磁、高分辨质谱确证。该合成方法原料易得,催化剂便宜、溶剂绿色、操作简便。     

昆仑雪菊中黄酮类化合物的提取分离及抗氧化活性评价

通过正交试验优化提取条件,利用大孔树脂、反相硅胶等柱层析手段对昆仑雪菊的粗提液进行分离,并采用DPPH法对各分离部位进行抗氧化活性评价。结果表明:正交优化分析得到最优提取条件是料液比为1∶20(g∶m L),用体积分数70%的乙醇浸泡、提取昆仑雪菊2次,温度为80℃,时间为1 h,得到最佳昆仑雪菊总黄酮提取率为9.92%;从粗提物中分离得到1个单体化合物,采用核磁共振(NMR)和电喷雾质谱(ESI-MS)鉴定其化学结构为金鸡查尔酮;DPPH活性测定结果表明此化合物的抗氧化活性强于阳性对照芦丁,其IC50为10.21μg/m L。     

响应面法优化新疆胀果甘草多糖的提取工艺

研究以乙醇为提取剂从新疆胀果甘草中提取多糖的工艺。在单因素实验的基础上,运用Box—Behnken中心组合实验和响应面法考察了提取温度、提取时间和料液比3个因素对甘草多糖提取率的影响,并优化了提取工艺。结果表明最佳工艺条件为：温度93℃,时间83min,料液比为21：1（mg：L）。在此条件下胀果甘草多糖提取率的预测值为10．59％,验证实验值为10．48％,两者相近,说明响应面法优化胀果甘草多糖提取的工艺可行。     

复方铁线蕨颗粒中总黄酮和总酚的提取及其对宫颈癌细胞的作用

目的提取复方铁线蕨颗粒中的总黄酮及总酚研究其对SiHa、HeLa、C-33A等宫颈癌细胞的增殖和凋亡的作用。方法从复方颗铁线蕨粒中按提取工艺提取并纯化得到总黄酮及多酚提取物,制作芦丁及没食子酸的标准曲线并采用紫外分光光度法测定含量;将不同浓度的总黄酮及总酚给予3种细胞,通过药物细胞毒性实验测定各细胞在2种不同提取物作用下的IC50值。以1/2IC50、IC50、2IC50作为低、中、高浓度给药,采用异硫氰酸荧光素(fluorescein isothiocyanate, FITC)偶联Annexin-V染色法检测细胞凋亡。结果复方铁线蕨颗粒剂中总酚含量为30.83%,总黄酮含量39.14%。与正常对照组相比,不同浓度的2种提取物给药下的SiHa、HeLa和C-33A细胞,随着浓度的增加抑制率增加。在总酚作用下SiHa细胞IC50为367μg/mL, HeLa细胞IC50为380μg/mL, C-33A细胞的IC50为256μg/mL。在总黄酮作用下SiHa细胞IC50为268μg/mL, HeLa细胞IC50为274μg/mL, C-33A细胞的IC50为110μg/mL。在总酚及总黄酮高中低浓度作用下3种细胞的凋亡率与正常对照组相比具有显著差异,且各个细胞总酚给药组和总黄酮给药组组内差异显著。结论复方铁线蕨颗粒剂提取的总酚及总黄酮能抑制SiHa、HeLa、C-33A细胞的增殖,诱导3种宫颈癌细胞凋亡。     

甘草总黄酮的超声波法提取工艺研究

以人工种植的甘草切片为主要原料,以乙醇为主要提取剂,对超声辅助提取法提取甘草总黄酮工艺进行研究,确定超声波法提取甘草总黄酮的最佳工艺。结果表明,影响甘草总黄酮提取率的因素主次依次是:超声温度>乙醇浓度>料液比>超声时间;超声波法提取甘草总黄酮的最佳工艺条件为:超声温度45℃,超声时间75min,乙醇浓度75%,料液比1∶12,在此参数下,甘草总黄酮的提取率最高,达到1.79%。     

三种甘草种子蛋白的提取方法、结构及抗氧化活性比较研究

以3种甘草(乌拉尔甘草、胀果甘草及光果甘草)种子为原料,通过水提法、乙醇提取法、醋酸提取法、碱溶酸沉法、磷酸盐缓冲液提取法提取蛋白,以提取率与含量为指标进行比较,选出最佳提取方法。通过红外光谱和扫描电镜分析甘草种子蛋白的结构特征,并通过研究对不同自由基的清除率测定其抗氧化活性。结果表明,水提法较适用于甘草种子蛋白的提取,其蛋白含量分别为36.54、30.80、30.12 mg/mL;3种蛋白的红外光谱均显出了典型的蛋白吸收峰,具有α-螺旋和β-折叠结构;扫描电镜-X射线能谱结果显示,3种甘草种子蛋白均较好地保留了蛋白的纤维结构,并且均含有一定含量的磷元素;当样品质量浓度为1.0 mg/mL时,乌拉尔甘草种子蛋白的清除DPPH自由基、羟自由基的能力与总还原能力均为最高,分别为92.37%、77.30%和2.344,胀果甘草次之,光果甘草为最低。由此可见,甘草种子蛋白具有较高的抗氧化活性。该研究可为深入探究和开发甘草种子资源提供理论依据。     

甘草酸和甘草次酸提取分离方法的研究进展

甘草是豆科多年生草本植物,甘草酸和甘草次酸等三萜类化合物是甘草的主要成分,为药食两用植物。本文综述了近10年甘草三萜类化合物中甘草酸和甘草次酸的提取及分离纯化方法,提取方法包括溶剂提取法、超声辅助提取法、微波辅助提取法和半仿生-酶提取法等,分离纯化方法包括重结晶法、大孔树脂法、膜分离法和固相萃取法等。针对甘草药材来源及甘草酸提取工艺考查指标混乱等问题进行了归纳总结,以期为甘草酸和甘草次酸提取分离的后续研究提供参考。     

Probiotics and prebiotics--perspectives and challenges

Owing to their health benefits, probiotics and prebiotics are nowadays widely used in yogurts and fermented milks, which are leader products of functional foods worldwide. The world market for functional foods has grown rapidly in the last three decades, with an estimated size in 2003 of ca US$ 33 billion, while the European market estimation exceeded US$ 2 billion in the same year. However, the production of probiotics and prebiotics at industrial scale faces several challenges, including the search for economical and abundant raw materials for prebiotic production, the low-cost production of probiotics and the improvement of probiotic viability after storage or during the manufacturing process of the functional food. In this review, functional foods based on probiotics and prebiotics are introduced as a key biotechnological field with tremendous potential for innovation. A concise state of the art addressing the fundamentals and challenges for the development of new probiotic- and prebiotic-based foods is presented, the niches for future research being clearly identified and discussed.     

常用消毒灭菌法及其机理与应用

介绍了采用消毒灭菌方法,有加热消毒法,紫外线辐射法和化学药剂消毒法。常用化学药剂有醛类、含氯消毒剂、醇类消毒剂以及高锰酸钾、生石灰等,阐释了消毒与灭菌两个概念的区别。     

European citizen and consumer attitudes and preferences regarding beef and pork

This paper presents the combined mid-term findings of the consumer research components of two EU Sixth Framework Programme integrated projects concerning meat, ProSafeBeef and Q-PorkChains. The consumer pillar of ProSafeBeef carried out eight focus group discussions in May 2008, in France, Germany, Spain and the UK. Q-PorkChains conducted a large-scale, web-based, consumer survey in January 2008 in Belgium, Denmark, Germany, Greece and Poland. The first project provides a set of qualitative data from a small cohort of focus groups and the second a set of quantitative data from a larger consumer sample. This paper draws together the main findings of both projects and provides a comprehensive overview of European citizens’ and consumers’ attitudes towards and preferences regarding beef and pork. In general, consumers consider meat to be a healthy and important component of the diet. Consumers support the development of technologies that can improve the health attributes of meat products and guarantee eating quality, but they have a negative view of what they see to be excessive manipulation and lack of naturalness in the production and processing of beef products. In the Q-PorkChains study consumer and citizen segments are identified and profiled. Consumer segments were built upon the frequency and variety of pork consumption. The citizen segments were built upon their attitudes towards pig production systems. Overall, the relationship between individuals’ views as citizens and their behaviour as consumers was found to be quite weak and did not appear to greatly or systematically influence meat-buying habits. Future studies in both projects will concentrate on consumers’ acceptance of innovative meat product concepts and products, with the aim of boosting consumer trust and invigorating the European beef and pork industries.     

益生素、益生菌与结肠癌

介绍了益生素和益生菌及其作用机理。在动物模型中，有大量的数据证实益生素和益生菌能够预防癌症．而在人体内还没有直接实验证据。它们抑制癌症的确切机理目前尚不清楚，其抑制机理可能是：肠道菌群代谢活动的改变，肠道理化环境的改变，潜在的致癌物质的黏附和降解，肠道菌群的改变、抗癌或抗诱变物质的形成、提高宿主的免疫应答、影响宿主的生理活动以及发酵不能被消化的食物并形成有益代谢产物。     

节能节水型印染助剂和设备的现状

从节能、节水、缩短工艺流程和环保的角度出发，介绍了国内外研制开发的一系列新型节能、节水型印染助剂和染整设备。     

原花色素及其开发应用

对原花色素的结构、化学特性、制备、分析方法、应用前景作一综述,并重点讨论其生理功能,为在功能性食品、药物、化妆品等领域的深入研究和开发提供参考。     

天然香精香料与生物技术

天然香精香料是高价值的精细化工产品和食品添加剂,但原料来源有限且提取成本高。利用生物技术生产这类产品具有广阔的前景。简述了发酵工程、酶工程、细胞工程和基因工程在香精香料中的应用,并探讨了生物技术在香精香料中的应用前景。     

毛霉型低盐速成豆豉工业化生产工艺与设备

本文介绍了毛霉型低盐速成豆豉的工业化生产工艺及生产线的关键设备。     

组学技术与果蔬采后质量和安全控制

果蔬可以提供营养, 有利于人类健康, 而果蔬的后熟及其与环境的相互作用会影响果蔬采后的质量和安全。对果蔬生物学过程的了解和掌握是减少果蔬采后损失和保障果蔬采后质量和安全的关键。在过去的10多年, 基于组学技术的系统生物学在了解果蔬后熟及其与环境相互作用的分子机制方面得到了越来越多的应用。本文对此做了细致的总结, 指出了存在的不足, 并提出了未来的发展方向。     

Heritability and correlations for body condition score and dairy form within and across lactation and age

The objectives of the current study were to investigate the relationship between body condition score (BCS) and dairy form and changes in genetic parameters for BCS and dairy form within and across lactations and age. Body condition score and dairy form were obtained from the Holstein Association USA, Inc. Records were edited to include those cows classified between 24 and 60 mo of age and between 0 and 335 d in milk (DIM). A minimum of 20 daughters per sire and 15 cows per herd-classification visit were required. The dataset consisted of 135,178 records from 119,215 cows. Repeatability, multiple trait, and random regression models were used to analyze the data. All models included fixed effects for herd-classification visit, age within lactations 1, 2, and 3 or higher, and 5th-order polynomials for DIM. Random effects included sire and permanent environment for all models. Random regression models included age at classification nested within sire or DIM and lactation number nested within sire. Genetic variance for both BCS and dairy form was lowest in early lactation and highest in midlactation. Genetic correlations within and across lactations were high. The genetic correlation between DIM 0 in lactation 1 and DIM 305 in lactation 3 was estimated to be 0.77 for BCS and 0.60 for dairy form. The genetic correlation estimate between 30 mo of age at classification and 50 mo of age at classification was 0.94 for both dairy form and BCS. The repeatability models appeared to generate accurate evaluations for BCS or dairy form at all ages and stages of lactation.