Changes in amino acids and lipids during embryogenesis of European lobster,Homarus gammarus(Crustacea:Decapoda)

摘要

We studied the amino acid and lipid dynamics during embryogenesis of Homarus gammarus.Major essential amino acids(EAA)in the last stage of embryonic development were arginine,lysine and leucine;major nonessential amino acids(NEAA)were glutamic acid,aspartic acid,valine and glycine.The highest percent of utilization occurred in respect to EAA(27.8%),mainly due to a significant decrease(p<0.05)of methionine(38.3%)and threonine(36.0%).NEAA also decreased significantly(p<0.05,11.4%),namely serine(38.1%),tyrosine(26.4%)and glutamic acid(25.7%).In contrast,the free amino acid content increased significantly(p<0.05)during embryonic development,especially the free nonessential amino acids(FNEAA).In the last stage,the most abundant FNEAA were glycine,proline,alanine and taurine,and the major free essential amino acids(FEAA)were arginine,lysine and leucine.Lipid content decreased significantly(p<0.05)during embryonic development.A substantial decrease in all neutral lipid classes was observed(>80% of utilization).Major fatty acids were 16:0,18:0,18:ln-9,18:2n-6,18:3n-3,20:5n-3 and 22:6n-3.Unsaturated(UFA)and saturated fatty acids(SFA)were used up at similar rates(76.5% and 76.3%,respectively).Within UFA,monounsaturates(MUFA)were consumed more than polyunsaturates(PUFA)(82.9% and 67.5%,respectively).