Changes in lipid composition during metamorphosis of bonefish (Albula sp.) leptocephali
Changes in lipid composition during metamorphosis of bonefish (Albula sp.) leptocephali
复制标题
细头北梭鱼 (Albula sp.) 变态过程中脂质成分的变化
作者：
D. Padrón;V. Lindley;E. Pfeiler
在北梭鱼 (Albulasp.) 幼虫 (leptocephali) 的变态过程中，所有能量需求均由内源化合物的分解提供，其中脂质分解代谢约占总能量产生的 80%。本研究的主要目的是表征所使用的脂质类别和脂肪酸。全身脂质含量分析表明，幼虫在 10 天期间损失了约一半（3.6 毫克）的总脂质。早期变态幼虫中中性和极性脂质的百分比分别为64.2%和35.8%；这些值在变态过程中几乎没有变化，表明两种脂质类别都被分解代谢。三酰甘油（所有变质阶段的主要中性脂质）减少了 1.8 毫克。占总脂质下降的一半。早期幼虫中主要的极性脂质——磷脂酰乙醇胺的水平在变态过程中下降了50%以上；在早期幼虫中未检测到的磷脂酰胆碱水平有所增加。可能用作能源的脂肪酸净减少量最大，分别为 16∶0 (30.4%)、14∶0 (13.8%)、16∶1n-7 (12.2%)、20∶5n-3 (7.7%)、18∶1n-9 (7.4%) 和 18∶4n-3 (6.9%)。早期幼虫中第二丰富的脂肪酸 22∶6n-3 的大部分是保守的。
During metamorphosis of bonefish (Albulasp.) larvae (leptocephali) all energy requirements are provided by breakdown of endogenous compounds, with lipid catabolism accounting for about 80% of total energy production. The principal objective of the present study was to characterize the lipid classes and fatty acids utilized. Analysis of whole‐body lipid content indicated that larvae lost about half (3.6 mg) of their total lipid during the 10‐d period. Percentages of neutral and polar lipid in early metamorphosing larvae were 64.2 and 35.8%, respectively; these values showed little change during metamorphosis, indicating that both lipid classes were catabolized. Triacylglycerols, the principal neutral lipid of all metamorphic stages, decreased by 1.8 mg. accounting for half of the decrease in total lipid. Levels of phosphatidylethanolamine, the principal polar lipid in early larvae, decreased by more than 50% during metamorphosis; levels of phosphatidylcholine, which was not detected in early larvae, increased. Fatty acids showing the largest net decreases, presumedly used as energy sources, were 16∶0 (30.4%), 14∶0 (13.8%), 16∶1n‐7 (12.2%), 20∶5n‐3 (7.7%), 18∶1n‐9 (7.4%), and 18∶4n‐3 (6.9%). Most of 22∶6n‐3, the second most abundant fatty acid of early larvae, was conserved.