Analytical Method for Nutirtional Condition of Marine Fish Larvae by Individual

本文建立了一种灵敏、简便的海水鱼仔稚鱼脂肪酸分析方法，以测定其二十二碳六烯酸（DHA）和二十碳五烯酸（EPA）的含量作为营养状况的指标。本研究将9-蒽基甲酯脂肪酸的高效液相色谱（HPLC）技术引入到新方法中，建立了一种新的方法。高灵敏度的荧光检测的酯，使一个人的一只眼睛和身体部分的分析。2.一些分析过程中的修改，以减少耗时的复杂操作。脂质提取后的所有过程都可以在单个一次性玻璃小瓶中进行。分析在3.5小时内完成，一天可分析10个样品。3.对日本丰贺湾和陆津湾捕获的18种326尾野生仔鱼的体细胞部分进行脂肪酸分析。结果表明，在所有个体中，显著的脂肪酸只有5种，分别为DHA（18- 32%）、棕榈酸（18- 27%）、EPA（4- 19%）、十八碳烯酸（7- 12%）和硬脂酸（4- 23%）。2.4-3.1和4.4-5.2 mm的褐鳎（CV 0.6-1.0）和4.8-6.0 mm的日本（CV 0.7-0.9）的变异系数较高。太平洋滨鹬的变异系数普遍较低（0.2-0.5，只有一个例外，为0.9）。野生海水鱼仔稚鱼在发育过程中，其必需DHA的含量在不同发育阶段有很大差异。

A sensitive and convenient procedure for fatty acid analysis of marine fish larvae has been developed in order to determine docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) contents as an indicator of their nutritional condition. Fatty acid content and composition in each individual of the wild marine fish larvae have been analyzed by the new procedure.1.High-performance liquid chromatography (HPLC) of fatty acid 9-anthrylmethyl esters was introduced to the new procedure. Highly sensitive fluorescent detection of the esters enabled the analysis of one eye and somatic part from one individual.2.Some processes of the analysis were modified to reduce time-consuming complicated operations. All processes after lipid extraction could be carried out in a single disposable glass vial. The analysis was completed within 3.5 hours, and about ten samples could be analyzed in one day.3.Somatic part of the 326 individuals of wild fish larvae (18 species) caught in the Funka and Mutsu Bays, Japan, were subjected to the fatty acid analysis. In all individuals, remarkable fatty acids were only five components, DHA (18-32 %), palmitic acid (18-27 %), EPA (4-19 %), octadecenoic acid (7-12 %) and stearic acid (4-23 %).4.DHA contents of the somatic part (μg/individual) were summarized for every nine individuals classified by body lengths. Coefficient of variance (CV) was high in the 2.4-3.1 and 4.4-5.2 mm brown sole (CV 0.6-1.0) and 4.8-6.0 mm Japanese anchovy (CV 0.7-0.9). Pacific sandlance showed generally lower CV (0.2-0.5 with one exception 0.9). The contents of DHA essential for marine fish larvae widely vary at specific stages during development of wild marine fish larvae.