Tracing the geographic origin of Sakuraebi (Sergia lucens) by DNA and stable isotope analyses

Abstract

The potential application of DNA and stable isotope analyses as tools for verifying the geographical origin of raw and processed (suboshi and kamaage) Sakuraebi from Suruga Bay in Shizuoka, Japan, and Taiwan was examined. No clear genetic differences were observed in partial mitochondrial DNA 16SrRNA sequences (404 bp) extracted from raw Sakuraebi from Suruga Bay and Taiwan. However, both raw and processed Sakuraebi from Suruga Bay had higher carbon and nitrogen isotope ratios than specimens from Taiwan. The results suggested that analyses of stable carbon and nitrogen isotopes were useful for determining the geographical origin of Sakuraebi. We also examined the effects of acidification and processing (i. e. sun-drying and boiling) on the stable carbon and nitrogen isotope ratios of raw Sakuraebi. Acidification caused a significant decrease in δ13C values and an increase in δ15N values of the raw Sakuraebi samples. Sun-drying had no significant effect on either δ13C or δ15N values, but boiling caused a decrease in δ15N values of several individuals of raw Sakuraebi. Copyright © 2014, Japanese Society for Food Science and Technology.