不同虾的组织中氨基脲存在形态及含量分析

Formation and content analysis of semicarbazide in wild and aquacultured Macrobrachium nipponense tissues

氨基脲在虾甲壳组织中普遍存在,同时又是呋喃西林的代谢标志物,在利用氨基脲检测结果判定虾中是否是由于使用呋喃西林导致氨基脲残留时,往往会造成判定结果错误,易给养殖者和贸易均造成巨大损失,因此需要对虾中内源性氨基脲的存在状况进行深入全面的分析。本实验研究了不同来源虾类不同组织中氨基脲含量水平、存在形态和组织分布特征,对比分析了海水虾和淡水虾组织中氨基脲含量的差异及野生环境和人工养殖环境中日本沼虾组织中氨基脲的含量差异。结果显示:氨基脲在虾的不同组织中浓度从高到低依次为:甲壳>眼柄>鳃>肌肉>头胸部>肝胰腺;虾肌肉组织中氨基脲总量含量为ND(未检出)~(16.91±1.89)μg/kg,肌肉组织中结合态氨基脲含量为ND~(2.26±0.97)μg/kg。虾肌肉组织结合态氨基脲在氨基脲总量中所占比例分别为ND~33.79%,甲壳组织中结合态氨基脲所占比例分别为ND~84.48%。甲壳、眼柄、鳃等虾的角质化组织中氨基脲结合态的比例大于肌肉组织中氨基脲结合态的比例。甲壳组织和眼柄组织中氨基脲主要以结合态形式存在,肌肉、鳃、肝胰腺和头胸部组织中氨基脲主要是以游离态形式存在。日本沼虾和罗氏沼虾中肌肉组织中氨基脲平均含量均大于1.0μg/kg。淡水虾肌肉、甲壳、眼柄和鳃组织中氨基脲含量比海水虾相应组织中氨基脲高。养殖池塘采集的日本沼虾甲壳、鳃、头胸部、肌肉组织氨基脲含量均高于湖泊采集的日本沼虾氨基脲含量,氨基脲在日本沼虾甲壳、眼柄组织中主要是结合态形式存在,其它组织中氨基脲以游离态形式存在,与其它品种虾类结果一致。

Semicarbazide,also known as hydrazinecarboxamide,is an endogenous substance in crustacean aquatic products,especially in shrimp shell tissues.Meanwhile,Semicarbazide is a metabolic marker of nitrofurazone.The detection results of semicarbazide could be used to determine whether residues of semicarbazide are caused by the use of nitrofurazone in shrimp.However,the results of the determination are always wrong,which resulted in losses to the farmers and the trade.Therefore,it is necessary to analyze the existence of endogenous semicarbazide in prawn thoroughly.The content,formation and distribution characteristics of semicarbazide in tissues of shrimp from different sources were studied.The difference of semicarbazide in tissues of seawater and freshwater shrimp was compared and analyzed.The difference of semicarbazide content in wild and aquaculture Macrobrachium Nipponense tissues was analyzed.The detection method of samples(shell,muscle,eyestalk,hepatopancreas,cephalothorax,and gill)were hydrolyzsis with hydrochloric acid,derivative with 2-nitrobenzaldehyde,extracted with ethyl acetate,separated by liquid chromatography,determined by tandem mass spectrometry,and quantified by internal standard method.The order of semicarbazide concentration in different tissues of shrimp from high to low was shell>eyestalk>gill>muscle>cephalothorax>hepatopancreas.The semiacrbazide content in muscle tissue was ND~16.91±1.89μg/kg,the bound semiacrbazide content in muscle tissue was ND~(2.26±0.97)μg/kg,and the proportion of semiacrbazide bound in muscle tissue was ND~33.79%,respectively.The proportion of semicarbazide in shell tissue was ND~84.48%,and the proportion of shell bound state in keratinized tissue of shell,eyestalk and gill was higher than that in muscle tissue.Semicarbazide mainly existed in shell and eyestalk of bound state,and in muscle,gill,hepatopancreas and cephalothorax of free state.The content in muscle,shell,eyestalk and gill tissue of freshwater shrimp was higher than that in the corresponding tissues of sea shrimp.This study provided essential data for the determination of semicarbazide residue and guaranteed the edible safety of aquatic shrimp products.