Improved method for measuring the δ15N compound-specific amino acids: Application on mesopelagic fishes in the South China Sea

作     者：Fuqiang Wang Ying Wu Lin Zhang Jie Jin Zuozhi Chen Jun Zhang Wing-man Lee Fuqiang Wang;Ying Wu;Lin Zhang;Jie Jin;Zuozhi Chen;Jun Zhang;Wing-man Lee

作者机构：State Key Laboratory of Estuarine and Coastal ResearchEast China Normal UniversityShanghai 200241China Center for Blue LifePilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Department of Physical and Environmental ScienceTexas A&M University-Corpus ChristiTexa 78412USA Key Field Scientific Experimental Station of South China Sea Fishery Resource and EnvironmentMinistry of Agriculture and Rural AffairsGuangzhou 510300China South China Sea Fisheries Research InstituteChinese Academy of Fishery SciencesGuangzhou 510300China 

出 版 物：《Acta Oceanologica Sinica》 (海洋学报（英文版）)

年 卷 期：2022年第41卷第1期

页      面：30-38页

核心收录：

学科分类：07[理学] 0713[理学-生态学] 

基　　金：The National Basic Research Program(973 Program)of China under contract No.2014CB441502 the National Natural Science Foundation of China under contract No.41876074 the Cross-research Center Project by QNLM under contract No.JCZX202007 

主　　题：δ13C of fatty acids δ15N of amino acids ion chromatography mesopelagic fishes Precon-IRMS 

摘      要：Compound-specific stable isotope analysis of individual amino acids(CSIA-AA)has been widely used in ecological and biogeochemical *** has been proven to be powerful in tracing the diet sources and trophic ***,assessing the N sources of mesopelagic fishes has been inconclusive because the mesopelagic fishes’unique domain(water depth ranged from 0 to 1000 m)and unresolved nitrogen isotopes of various *** study proposes a new method for coupling instruments(ion chromatography and PreconIRMS)and chemical method of oxidation-reduction of amino acids,and also combinedδ15N of AAs withδ13C of fatty acids(FAs)to analyze the trophic interactions of mesopelagic fishes in the South China Sea(SCS).AAs were isolated by ion chromatography with high peak resolution and collected by an automated fraction *** chemical method then converted the AAs into N2 O with a robust oxidation yields and suitable molar ratio of NH2 OH ***,theδ15N of AAs at 20 nmol were measured with a reasonable precision(0.6‰).With this method,this study report the first batch high precisionδ15N of AAs andδ13C of FAs of mesopelagic fishes collected from *** luetkeni,Chauliodus minimus and Bathygadus antrodes showed similarδ13C values of 20:4 n-6(~-28‰),while Argyropelecus affinis and Stomias had similar values(~-32‰).These results reflect that mesopelagic fishes had complex diet *** increase of 4‰inδ15N of glutamic acid(Glu)was found between piscivorous and planktivorous fishes,which might suggest a trophic discrimination factor of mesopelagic fishes in the *** study usedδ13C of 20:4 n-6 to reveal the diet sources of mesopelagic fishes andδ15N of Glu to clarify trophic level between piscivorous and planktivorous ***,this combinative method could therefore ultimately be applied in a variety of deep-sea ecosystem.