秋季南黄海表层海水中溶解氨基酸的分布与组成研究

用高效液相色谱法对2010年9月南黄海33个站位表层海水中总水解氨基酸(THAA)、溶解游离氨基酸(DFAA)、溶解结合氨基酸(DCAA)的分布、组成以及它们与环境因子的相关性进行了研究。结果表明:THAA平均浓度为2.08μmol/L,DFAA平均浓度为0.39μmol/L,DCAA平均浓度为1.69μmol/L。THAA浓度的分布大致呈近岸高、远岸低的特点;DFAA分布的规律性较差,在东部海域(中心约在35°N,123°E)出现高值。相关性分析显示溶解氨基酸与叶绿素a(Chl-a)、溶解无机氮(DIN)、细菌丰度、温度和盐度之间均无显著相关性。THAA中含量较高的个体氨基酸为丝氨酸、甘氨酸、天门冬氨酸、谷氨酸和丙氨酸,总和占70.59%。DFAA、DCAA中的主要成分与THAA基本相同。THAA中个体氨基酸的组成以34°N为界分为南北2个海区呈现明显的区域性特点。

Distribution and Composition of Dissolved Amino Acids in the Surface Water of the South Yellow Sea during Autumn

A high performance liquid chromatography(HPLC) method was applied to analyze the distribution and composition of total hydrolyzed amino acids(THAA),dissolved free amino acids(DFAA),dissolved combined amino acids(DCAA) in the surface water samples collected from 33 stations located in the South Yellow Sea in September 2010.The correlation between the dissolved amino acids and environmental factors was also studied.The results showed that the average concentrations of THAA,DFAA and DCAA were 2.08,0.39,1.69 μmol/L,respectively.The concentrations of THAA were higher in the coastal waters than in the open sea;the distribution of DFAA did not exhibit regular pattern,but the concentrations of DFAA were high in the eastern area(centered at 35°N,123°E).No significant correlation was found between dissolved amino acids and environmental factors such as chlorophyll a(Chl-a),dissolved inorganic nitrogen(DIN),bacteria abundance,temperature and salinity.Major constituents of THAA in the study area were serine,glycine,aspartic acid,glutamic acid and alanine,accounting for 70.59% of total THAA.Basically,DFAA and DCAA had the same major constituents as THAA.An obvious regional characteristic was revealed in the composition of individual amino acids between the north and south area of the South Yellow Sea demarcated by 34°N.