Study On The Inhibited Effect Of Ferment Lactic Acid Bacteria Supernatant Against Human Pathogens

Lactic acid bacteria are a group of related bacteria that produce lactic acid as a result of carbohydrate fermentation. Since ancient times, these microbes have been broadly used by human beings in the production of fermented or cultured food products.After hundreds of years' research on lactic acid bacteria, their sources, nature, function and application have been understood well, and nowadays, the focus is on the antagonistic action of lactic acid bacteria home and abroad.With the increased awareness of health, people tend to prevent the illness rather than treat it. Therefore, functional foods, especially, products of lactic acid bacteria appeal to more and more people.In this paper, the inhibited effects of 17 strain lactic acid bacteria(15 strains were isolated from Koumiss that were taken from grassland in Inner Mongolia) against 7 strain pathogenic bacteria were studied. Also, the inhibitory character and range of lactic acid bacteria were researched. The study aims to select some strains which have stronger inhibitory activity as yeasts for further production and application.The result shows that lactic acid bacteria with pH 2.0-3.0 low enough can best inhibit the growth of the most common human pathogens, while will stop inhibitory activity with pH topped to 6.0. In addition, the inhibitory activity is stable in heat and constant with proteinase, but weakened by NaOH solutions.