Joint Institute for Food Safety and Applied Nutrition, University of Maryland, Maryland, USA and Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Maryland, USA.
Department of Chemistry, Vancouver Island University, Nanaimo, Canada.
Anal Methods. 2021 Aug 12;13(31):3493-3503. doi: 10.1039/d1ay00755f.
Various samples of the Eastern oyster, Crassostrea virginica, were collected from five harvest bay areas in the Gulf of Mexico coastal waters of Florida (FL), Louisiana (LA) and Texas (TX). Cadmium and lead concentrations from the extracted whole-body soft tissues were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS), and bulk δ13C and δ15N isotope ratios and amino-acid-specific δ13C values were analyzed via isotope ratio mass-spectrometry (IRMS). The combined data was subjected to multivariate statistical analysis to assess whether oysters could be linked to their harvest area. Results indicate that discriminant analysis using the δ13C values of five amino acids-serine, glycine, valine, lysine and phenylalanine-could discriminate oysters from two adjacent harvesting in Florida with 90% success rate, using leave-one-out cross validation. The combination of trace elements and isotope ratios could also predict geographic provenance of oysters with a success rate superior to the isolated use of each technique. The combinatory approach proposed in this study is a proof-of-concept that compound specific stable isotope analysis is a potential tool for oyster fisheries managers, wildlife, and food safety enforcement officers, as well as to forensics and ecology research areas, although significantly more work would need to be completed to fully validate the approach and achieve more reliable statistical results.
从佛罗里达州 (FL)、路易斯安那州 (LA) 和德克萨斯州 (TX) 的墨西哥湾沿海海域的五个收获湾地区采集了各种东方牡蛎 (Crassostrea virginica) 样本。通过电感耦合等离子体质谱法 (ICP-MS) 分析了从提取的全身体软组织中得出的镉和铅浓度，并通过同位素比质谱法 (IRMS) 分析了总 δ13C 和 δ15N 同位素比值和氨基酸特异性 δ13C 值。将综合数据进行多元统计分析，以评估牡蛎是否可以与其收获区域相关联。结果表明，使用判别分析，通过五种氨基酸-丝氨酸、甘氨酸、缬氨酸、赖氨酸和苯丙氨酸的 δ13C 值，可以以 90%的成功率区分佛罗里达州两个相邻收获区的牡蛎，使用留一法交叉验证。微量元素和同位素比值的组合也可以预测牡蛎的地理起源，成功率优于每种技术的单独使用。本研究中提出的组合方法证明了基于特定稳定同位素分析的方法是牡蛎渔业管理者、野生动物和食品安全执法人员以及法医和生态学研究领域的潜在工具，尽管需要完成更多的工作来完全验证该方法并获得更可靠的统计结果。
