Abstract

Evaluation of Lactobacillus rhamnosus viability effect on reduction of aflatoxin M1 in probiotic yogurtEvaluation of Lactobacillus rhamnosus viability effect on reduction of aflatoxin M1 in probiotic yogurt

Author(s): F.Tajalli1, Sarabi M.Jamab, N.Adibpour, M.Mehraban Sang Atash, R.Karazhian

Aflatoxins are a group of toxin compounds in many foods and animal feeds and have potent hepatocarcinogens in man as acute toxicants[1]. Physical and chemical approaches for elimination of mycotoxins are limited due to problems which they cause in food safety. Microbial detoxification is one of the aflatoxin removal methods such as aflatoxin M1. Many reports implicate that some lactic acid bacteria strains are able to adsorb aflatoxins by their cell walls. This research was carried out on evaluation of Lactobacilus rhamnosus ability for aflatoxin M1 adsorbtion in probiotic yogurt. In this research, Lactobacilus rhamnosus with starter culture were inoculated to non aflatoxin reconstituted skim milk about 108 cfu/ml. After that, the yogurt samples were contaminated by aflatoxin M1 in 0.1, 0.5 and 0.75 ppb concentrations. Aflatoxin M1 residuals were determined in the supernatant of the samples by competitive ELISA in first, seventh, fourteenth and twentyonce days after yogurt processing. The results showed, however, both tested probiotic bacteria (Lactobacillus rhamnosus subspecies GG) and starter cultures (Streptococcus thermophilus and Lactobacillus bulgaricusphilus) are able to adsorb toxins, but the ability of probiotic bacteria was statistically higher than starter cultures in yogurt.