发酵法生产DHA过程中油脂及DHA质量分数的快速定量测定

针对发酵法生产DHA生产过程实时监控的需求，建立了一种简单、快速、准确的检测菌体细胞中油脂及DHA含量的方法。主要考察了菌体干燥，菌体细胞破壁方法、油脂抽提溶剂、油脂甲酯化方法以及内标选择等对菌体内油脂及DHA含量测定的影响等，确定了以湿菌体为分析样本，采用酸热法细胞破壁、正己烷抽提油脂、十九烷酸甲酯为内标、碱催化甲酯化测定发酵液中油脂及DHA含量方法，整个分析过程可在1~2 h内完成，特别适合DHA发酵过程的中间分析化验。
A simple，fast and accurate method was established to determine the composition and contents of lipids and docosa-hexaenoic acid（DHA） during fermentation process for DHA production. The detection for lipids and DHA contents in Schizochytrium was optimized by drying methods，cell disruption methods，the ways of lipid extraction，the methods of methyl esterification and the selection of internal standards. The optimal analysis used an acid-heating method for cell disruption，n-hexane for lipid extraction，nonadecanoic acid methylester as the internal standard and methyl esterification catalyzed by alkali catalyst. It was particularly suitable for the intermediate analysis during fermentation process for DNA production which could be accomplished within 1-2 hours