Bennett Pamela M, Weber Lynn P, Janz David M
Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, Saskatchewan S7N 5B3, Canada.
J Aquat Anim Health. 2007 Sep;19(3):179-85. doi: 10.1577/H06-044.1.
Lipids, including triglycerides, are important variables in fish bioenergetics and can be used to estimate overall fish condition. Triglycerides are the major energy storage form in fish and therefore are a more ecologically and physiologically relevant measure of bioenergetics than total lipids. Chloroform-methanol-extracted total body lipids (Bligh and Dyer) and total body triglycerides determined in chloroform-methanol extracts and unextracted whole-body fractions were measured in four fish species: northern pike Esox lucius, burbot Lota lota, slimy sculpin Cottus cognatus, and spottail shiners Notropis hudsonius. Determinations of total body lipids were consistently greater than those of total body triglycerides when measured in the same solvent-extracted fraction, although both measures followed similar trends. In an effort to eliminate the need for extraction with organic solvents, we compared the performance of an enzyme-based triglyceride assay in both the solvent-extracted fraction and a whole-body unextracted homogenate for each fish. The chloroform-methanol-extracted triglyceride values were consistently lower than triglycerides measured in the unextracted whole-body homogenate. In addition, comparison of triglyceride measurements revealed limitations to the solvent extraction and subsequent triglyceride determinations in lean fish. Thus, in addition to being simple, rapid, and not requiring organic solvents, determination of triglycerides in an unextracted whole-fish homogenate may be a useful alternative to chloroform-methanol-based methods of lipid extraction and subsequent triglyceride measurement.
脂质，包括甘油三酯，是鱼类生物能量学中的重要变量，可用于评估鱼类的整体状况。甘油三酯是鱼类主要的能量储存形式，因此与总脂质相比，它在生态和生理上更能反映生物能量学情况。我们测定了四种鱼类的氯仿 - 甲醇提取的全身脂质（布莱和戴尔法）以及氯仿 - 甲醇提取物和未提取的全身部分中的全身甘油三酯含量，这四种鱼分别是白斑狗鱼（Esox lucius）、江鳕（Lota lota）、粘杜父鱼（Cottus cognatus）和细纹鳟（Notropis hudsonius）。在相同溶剂提取的部分中测量时，全身脂质的测定值始终大于全身甘油三酯的测定值，尽管两种测量结果都呈现相似趋势。为了避免使用有机溶剂进行提取，我们比较了基于酶法的甘油三酯测定在每种鱼的溶剂提取部分和未提取的全身匀浆中的性能。氯仿 - 甲醇提取的甘油三酯值始终低于未提取的全身匀浆中测得的甘油三酯值。此外，甘油三酯测量结果的比较揭示了瘦鱼中溶剂提取及后续甘油三酯测定存在的局限性。因此，除了简单、快速且无需有机溶剂外，测定未提取的全鱼匀浆中的甘油三酯可能是基于氯仿 - 甲醇的脂质提取及后续甘油三酯测量方法的一种有用替代方法。
