Antimutagenic Effects of Milk Fermented by Lactobacillus helveticus L89 and a Protease-Deficient Derivative

¹ Dairy Research Centre, Department of Food Science and Technology, Université Laval, Québec, QC, Canada G1K 7P4
² Department of Food Science and Technology, Oregon State University, Corvallis 97331-6602

The antimutagenic effects of whey, acetone extracts, and protein fractions isolated from milk that had been fermented by Lactobacillus helveticus L89 were investigated using the mutagen 4-nitroquinoline-N'-oxide in the Ames test (Salmonella typhimurium TA 100). Fermented milk significantly inhibited mutagenesis induced by 4-nitroquinoline-N'-oxide. However, milk fermented by a nonproteolytic variant of the same strain showed no inhibitory effects. Results were similar for the whey fractions and acetone extracts of the fermented milks. After fermentation, milk proteins were fractionated by size-exclusion HPLC and were tested for antimutagenicity. The fraction showing the greatest activity was further analyzed by reverse-phase HPLC. Our results indicate that antimutagenic compounds are produced in milk during fermentation by L. helveticus, and the release of peptides is one possible contributing mechanism.

Key Words: Lactobacillus helveticus • peptides • milk fermentation • 4-nitroquinoline-N'-oxide antimutagenicity

Submitted on December 21, 1995
Accepted on March 6, 1997

This article has been cited by other articles:

				J. G. LeBlanc, C. Matar, J. C. Valdez, J. LeBlanc, and G. Perdigon Immunomodulating Effects of Peptidic Fractions Issued from Milk Fermented with Lactobacillus helveticus J Dairy Sci, November 1, 2002; 85(11): 2733 - 2742. [Abstract] [Full Text] [PDF]

				C. Bos, C. Gaudichon, and D. Tome Nutritional and Physiological Criteria in the Assessment of Milk Protein Quality for Humans J. Am. Coll. Nutr., April 1, 2000; 19(90002): 191S - 205. [Abstract] [Full Text] [PDF]