GROWTH AND SURVIVAL OF PROBIOTIC LACTIC ACID BACTERIA IN THE PRESENCE OF HETEROCYCLIC AROMATIC AMINES

Abstract

Heterocyclic aromatic amines (HCAs) ingested with heat-processed meat can contribute to colon cancer development. Those compounds interact with human intestinal microbiota. Under the research study, the effect was analyzed of IQ, MeIQx, or PhIP amines (each of them at 5 and 25 μg/ml concentration rates) on the growth (24 h cultivation in MRS broth) and survival (incubation for max. 120 h in a phosphate buffer) of four probiotic strains of Lactobacillus. It was found that no concentration level of the HCAs analyzed impacted the growth of bacteria. A higher concentration level of IQ (25 μg/ml) decreased the survival of Lb. casei0900 after a 24 h period of incubation. MeIQx and PhIP also decreased the survival of Lb. paracasei0919 after a 24 h period of incubation. Totally, the count of living cells decreased from 10 9 cfu/ml to 10 8 cfu/ml. Three strains were absolutely resistant to PhIP during a 120 h period of incubation. The results obtained prove that the probioticbacteria studied maintain their high viability in the presence of the amines tested and, probably, they can bind together with them in human colon and, then, the aggregated particles are removed from the human body.