Enzymatic determination of carnosine in meat and fish using β-Ala-Xaa dipeptidase and histidine ammonia-lyase derived from Pseudomonas putida NBRC100650

Abstract

Carnosine is a naturally occurring dipeptide and a functional component in foods, while also showing health-promoting effects. Generally, food-derived carnosine is quantified via high-performance liquid chromatography (HPLC). We have developed a method for quantifying carnosine in foods using microbial enzymes, β-Ala-Xaa dipeptidase (BapA) and histidine ammonia-lyase (HAL). The carnosine concentrations in extracts of chicken, pork, beef, bonito, and tuna were determined via both HPLC and enzymatic determination. The carnosine contents measured via enzymatic determination were in agreement with those determined via conventional HPLC analysis. Relative standard-deviation values of the conventional HPLC method and the enzymatic determination of carnosine in foods were 0.728-5.76% and 0.504-4.58%, respectively. The recovery of carnosine in food extracts via enzymatic determination was 97-103%. Therefore, the developed enzymatic determination technique using BapA and HAL can be used for the determination of carnosine in meats and fishes with comparable accuracy to that of conventional HPLC analysis.

Keywords: Carnosine; Enzymatic determination; Histidine ammonia-lyase; Imidazole dipeptide; β-Ala-Xaa dipeptidase.