Cloning and Purification of Ornithine Transcarbamoylase from Lactobacillus brevis and Its Application on Regulating Ethyl Carbamate Formation in Chinese rice wine

Abstract

It was studied that ornithine transcarbamoylase played important roles in ethyl carbamate (EC) formation. Ornithine transcarbamoylase (OTCase) can degrade citrulline, a precursor of EC, through arginine deiminase pathway. Therefore, they are generally added to regulate EC catabolism in rice wine fermentation. In this work, OTCase were added in different concentration and ferment time. It turned out addition of OTCase could reduce EC to some extent, especially for low concentration enzyme addition and mid-stage addition time. Furthermore, the production of amino acids, volatile flavor compounds and sense of taste were not markedly affected. The discoveries reveal that EC can be reduced by supplying OTCase while rice wine leavening. Key words: Ethyl carbamate, Ornithine transcarbamoylase, Rice wine fermentation, Enzyme inhibition