Toxicological evaluation for food applications of transglutaminase from a newly isolated Bacillus circulans BL32.

摘要

This study aimed to submit the transglutaminase (TGase; protein-glutamine gamma-glutamyltransferase) from a Bacillus circulans strain isolated from the Amazon environment to in vivo and in vitro toxicological evaluations in order to assess its safety for food use. The in vivo assay used male Wistar rats in a subacute 14 day oral feeding test using a liquid TGase enzyme preparation administered to 150 U kg b.wt. day--1. Evaluation of cytotoxicity, genotoxicity and mutagenic effects of this microbial TGase was carried out using Chinese hamster lung fibroblasts. No evidence of short term in vivo toxicity was found for the enzymic preparation in the subacute 14 day oral toxicity study using white Wistar rats. Furthermore, there were no statistical differences between the groups for relative weight gain and for haematological and clinical chemistry values. Histopathological examination of liver, kidneys, spleen, thymus, adrenal glands, heart, lungs and brain did not reveal any treatment-related changes. In addition, there was no evidence of cytotoxicity, genotoxicity or mutagenic effects of the simple application of 150 U treatment--1 of the microbial TGase on Chinese hamster lung fibroblasts cultured cells. No safety concerns were identified in this study for the BcTGase preparation produced under controlled cultivation conditions. From these results, it can be concluded that the microbial TGase from B. circulans BL32 is safe for food applications and has the potential for industrial use.