Determination of precise nitrogen stable isotopic baselines from heterotrophic organism in coastal ocean environments using compound specific isotope analysis of amino acids

Bohyung Choi; Kyung-Hoon Shin

doi:10.1016/j.marpolbul.2021.112777

Determination of precise nitrogen stable isotopic baselines from heterotrophic organism in coastal ocean environments using compound specific isotope analysis of amino acids

Mar Pollut Bull. 2021 Oct:171:112777. doi: 10.1016/j.marpolbul.2021.112777. Epub 2021 Jul 28.

Authors

Bohyung Choi¹, Kyung-Hoon Shin²

Affiliations

¹ Department of Marine Sciences and Convergent Technology, Hanyang University, Ansan 426-791, Republic of Korea; Fisheries Science Institute, Chonnam National University, Republic of Korea.
² Department of Marine Sciences and Convergent Technology, Hanyang University, Ansan 426-791, Republic of Korea. Electronic address: shinkh@hanyang.ac.kr.

PMID: 34332356
DOI: 10.1016/j.marpolbul.2021.112777

Abstract

We sampled mussels (Mytilus edulis) along the coast of the Korean peninsula, and determined their trophic position (TP) using the nitrogen isotope ratio of amino acids (TP_glu/phe). The TP_glu/phe of mussels (2.0 to 2.5) is higher than TP of herbivores, suggesting that TP normalization is required to remove the trophic enrichment effect on basal nitrogen isotope ratio. We found similar trends in spatial variation between nitrogen isotopic baseline based on nitrogen isotope ratio of bulk tissue (δ¹⁵N_base-bulk) and that of phenylalanine (δ¹⁵N_base-phe) in mussels, reflecting different nitrogen sources among sampling sites. The present study suggests that δ¹⁵N_base-bulk and δ¹⁵N_base-phe are powerful tools to trace nitrogen isotopic baselines from primary consumers as well as higher TP organisms.

Keywords: CSIA of amino acids; Isotopic baseline; Nitrogen isotope; Trophic position.

MeSH terms

Amino Acids*
Food Chain
Nitrogen Isotopes / analysis
Nitrogen* / analysis
Oceans and Seas

Substances

Amino Acids
Nitrogen Isotopes
Nitrogen