Bell M V, Dick J R, Kelly M S
Institute of Aquaculture, University of Stirling, Scotland, United Kingdom.
Lipids. 2001 Jan;36(1):79-82. doi: 10.1007/s11745-001-0671-2.
The sea urchin Psammechinus miliaris (Gmelin) (Echinodermata: Echinoidea) was shown by using a deuterated tracer (D5-18:3n-3) and quantitation by negative chemical ionization gas chromatography-mass spectrometry to convert 18:3n-3 to 20:5n-3. The rate of conversion was very slow, corresponding to 0.09 microg/g tissue/mg 18:3n-3 eaten over 14 d. Deuterated arachidonic acid (D8-20:4n-6) was also included in the diet to give a measure of the relative amounts of diet eaten by the different animals. The recovery of this fatty acid in tissue lipids was 33.7% compared with only 0.95% recovery of D5-18:3n-3 and its anabolites, indicating that the majority of the D5-tracer was catabolized. Considerable elongation of D5-18:3n-3 into 20:3n-3 and a trace of 22:3n-3 was found, and these were accompanied by minor amounts of the intermediates 18:4n-3 and 20:4n-3. No deuterated 22:6n-3 was found.
利用氘代示踪剂（D5-18:3n-3）并通过负化学电离气相色谱-质谱法定量分析，结果表明海胆球海胆（Psammechinus miliaris，Gmelin）（棘皮动物门：海胆纲）可将18:3n-3转化为20:5n-3。转化速率非常缓慢，相当于14天内每克组织每毫克摄入的18:3n-3中有0.09微克发生了转化。日粮中还添加了氘代花生四烯酸（D8-20:4n-6），以衡量不同动物的日粮摄入量。该脂肪酸在组织脂质中的回收率为33.7%，而D5-18:3n-3及其合成代谢产物的回收率仅为0.95%，这表明大部分D5-示踪剂被分解代谢。研究发现，D5-18:3n-3大量延长为20:3n-3，并生成微量的22:3n-3，同时伴有少量的中间产物18:4n-3和20:4n-3。未发现氘代22:6n-3。
