摘要
Lipids of Neocalanus cristatus and Eucalanus bungii (C3 to adults), collected in March, May, and December from various depths (0–2000 m) were studied in the Oyashio region, western North Pacific. Total lipid and wax ester contents of younger N. cristatus stages increased during the development, being higher in May than in March and December. Major fatty acids of younger N. cristatus were 16:0, 20:5(n − 3), and 22:6(n − 3) and the dominant alcohols were 16:0, 16:1(n − 7), 20:1(n − 9)/(n − 11) and 22:1(n − 11). The energy-rich 20:1 and 22:1 moieties increased from the younger to the adult stages showing the importance of lipid biosynthesis which may be advantageous for successful overwintering and reproduction at depth. The 16:4(n − 1) fatty acid, characteristic of a diatom diet increased in May, particularly in the younger stages. Our results suggest that the diatom-dominated feeding mode of younger N. cristatus during the spring bloom is important for an effective accumulation of wax esters. In contrast to N. cristatus, E. bungii accumulated substantial amounts of triacylglycerols. The total lipid and triacylglycerol content increased slightly toward the older developmental stages. The major fatty acids were 16:0, 16:1(n − 7), 18:1(n − 9) and (n − 7), and 20:5(n − 3). There was no evidence of developmental or seasonal changes in the fatty acid composition. The differences in the lipid storage modes of both copepods via wax esters or triacylglycerols are species-specific but their fatty acid compositions varied according to diet and developmental stage, especially in N. cristatus. These lipid characteristics are discussed in relation to reproduction, feeding modes, diapause and overwintering strategies.
摘要译文
在北太平洋西部的Oyashio地区研究了3月，5月和12月从不同深度（0-2000米）收集的Neocalanus cristatus和Eucalanus bungii（C3至成虫）的脂质。年轻N. cristatus阶段的总脂质和蜡酯含量在开发期间增加，5月份高于3月和12月。较年轻的N. cristatus的主要脂肪酸是16：0，20：5（n - 3）和22：6（n - 3），优势醇为16：0,16：1（n - 7），20：1（n - 9）/（n - 11）和22：1（n - 11）。富含20：1和22：1的部分从较年轻阶段增加到成熟阶段，表明脂质生物合成的重要性，这可能有利于成功的越冬和深度繁殖。6：4（n - 1）脂肪酸，硅藻饮食的特征在5月增加，特别是在较年轻阶段。我们的研究结果表明，硅藻为主的喂养方式为年轻的N.春季开花期间的cristatus对于有效积累蜡酯很重要。与N. cristatus相比，E。bungii积累了大量的三酰基甘油。总脂质和三酰基甘油含量在较老的发育阶段略有增加。主要脂肪酸为16：0,16：1（n \x3d 7），18：1（n-9）和（n-7），以及20：5（n-3）。没有证据表明脂肪酸组成发育或季节性变化。通过蜡酯或三酰基甘油的两种桡足类脂质储存模式的差异是物种特异性的，但它们的脂肪酸组成根据饮食和发育阶段而变化，特别是在N. cristatus中。讨论了这些脂质特征与繁殖，摄食模式，滞育和越冬策略有关。
YuichiroYamada[a];ShuheiNishida[b];MartinGraeve[c];GerhardKattner[c];. Lipid and fatty acid/alcohol compositions of the subarctic copepods Neocalanus cristatus and Eucalanus bungii from various depths in the Oyashio region, western North Pacific[J]. Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology, 2016,198: 57-65