Evaluation of the impact on food safety of a Lactobacillus coryniformis strain from pickled vegetables with degradation activity against nitrite and other undesirable compounds

ABSTRACT

Four strains of lactic acid bacteria showing antimicrobial activity against some food-spoilage microorganisms or pathogens, including both Gram-negative and -positive strains, were isolated from naturally fermented pickled vegetables and a traditional cheese product. Among these isolates, Lactobacillus coryniformis strain BBE-H3, characterised previously to be a non-biogenic amine producer, showed a high level of activity in degrading sodium nitrite and exhibited the ability to eliminate ethyl carbamate and one of its precursors, urea. The antimicrobial substance produced by L. coryniformis BBE-H3 was found to be active at an acidic pH range of 4.0–4.5. The antimicrobial activity of this strain decreased differentially after treatment with proteolytic enzymes (pepsin, papain, trypsin and proteinase K), implying this growth inhibitory compound is either a protein or a polypeptide. The results of this study show the suitability of L. coryniformis BBE-H3 as a starter in food manufacturing processes, and demonstrate its potential role in eliminating food origin carcinogens such as sodium nitrite and ethyl carbamate.

KEYWORDS:

• Lactobacillus coryniformis
• food safety
• biogenic amines
• nitrite
• antimicrobial activity
• ethyl carbamate

Acknowledgements

The authors thank Professor Paul O’Toole (University College Cork, Ireland) and Professor Wang Zhengxiang (Tianjin University of Science & Technology) for kindly providing indicator strains.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was supported by the Major State Basic Research Development Program of China [grant number 2012CB720802] and the 111 Project [grant number 111-2-06].