OPTIMIZATION OF MICROBIOLOGICAL ASSAY FOR FOLATE IN FOODS

食品中叶酸微生物测定的优化

• 批准号: 6107661
• 负责人: TUNG-SHAN CHEN
• 金额: --
• 依托单位: CALIFORNIA STATE UNIVERSITY NORTHRIDGE
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-01 至 1999-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6107661
• 关键词: Lactobacillus casei; analytical method; bioassay; folate; food additives; food processing /preparation; food quality /standard; food science /technology; high performance liquid chromatography; method development; microbiology; nutrient bioavailability; nutrition related tag

The overall objective of the proposed work is to optimize the methodology for folate analysis of food employing microbiological assay, by identifying improved procedures in various stages of the assay. The results obtained may lead to standardization of the analytical methodology for folate determination in foods and to stimulate further research that would increase the reliability and validity of food folate database. Accurate food-composition and intestinal-absorption data are essential to further our understanding of the bioavailability of food folate and to assess the human dietary folate requirements. Significant health benefits may also derive from update food folate information in light of the recently acknowledged roles of folate in neural tube defects, cardiovascular disease and cancer. There are three major steps in the microbiological assay for food folate: sample extraction, enzyme treatment and Lactobacillus casei assay. Variations in folate values of selected food items caused by varied conditions in each stage of the analysis will be quantified. The variables in the extraction procedures to be studied are: method of sample homogenization, extracting buffer used, ratio of sample to buffer, completeness of sample extraction, level of ascorbic acid added to buffer, heat treatment, pH adjustment of sample extract, method for clarification of sample extract, and storage stability of sample extract. In enzyme treatment of samples, the type and source of enzymes and conditions for incubation will be examined. Specific variables in the L. Casei assay to be investigated include the source and preparation of the calibrant, preparation of inoculum and culture medium, time and temperature of incubation, volume of sample extract to be assayed and the adaptation of microplate bioanalytical techniques for L. Casei assay. Additional specific objectives are to establish optimal conditions for sample analysis in selected food items and to determine if a general analytical procedure may be applicable to various types of food for folate determination. The final component of the proposed work focuses on the application of the refined analytical methodology to study the kinetics of folate destruction and the retention of folate during food preparation, processing and storage.

拟议工作的总体目标是优化 采用微生物测定法对食品进行叶酸分析的方法， 通过确定测定各个阶段的改进程序。 这 获得的结果可能导致分析的标准化 食品中叶酸测定方法并进一步刺激 提高食品叶酸可靠性和有效性的研究 数据库。准确的食物成分和肠道吸收数据 对于进一步了解食物的生物利用度至关重要 叶酸并评估人类膳食叶酸需求。重要的 更新食品叶酸信息也可能带来健康益处 鉴于最近公认的叶酸在神经管缺陷中的作用， 心血管疾病和癌症。 整个过程主要分为三个步骤 食品叶酸的微生物测定：样品提取、酶处理 和干酪乳杆菌测定。 选定的叶酸值的变化 在分析的每个阶段中，由不同条件引起的食品将 被量化。 要研究的提取过程中的变量 是：样品均质化方法、使用的提取缓冲液、比例 样品至缓冲液、样品提取的完整性、抗坏血酸水平 缓冲液中添加酸、热处理、样品提取物的 pH 调节、 样品提取物的澄清方法和样品的储存稳定性 提炼。在样品的酶处理中，酶的类型和来源 并将检查孵化条件。 具体变量在 待研究的 L. Casei 测定包括 校准物、接种物和培养基的制备、时间和 培养温度、待测定样品提取物的体积和 将微孔板生物分析技术应用于 L. Casei 测定。 其他具体目标是建立最佳条件 对选定食品进行样本分析，并确定一般情况是否存在 分析程序可适用于各种类型的食品 叶酸测定。 拟议工作的最后一部分重点是 论应用精细化分析方法来研究 食物中叶酸破坏和叶酸保留的动力学 制备、加工和储存。