Study On The Antibacterial Effect Of Lactobacillus Plantarum P1 On Foodborne Pathogenic Bacteria And The Adsorption Function Of Phthalates

In recent years,food safety incidents occurred frequently and became increasingly fierce.Pathogenic bacteria and chemically hazardous substances are two common food pollutant.Food safety is directly related to human health.Therefore,we need to adopt effective means to solve food safety problems.With the growth of the lactic acid bacteria family and more probiotic functions being discovered,lactic acid bacteria has become an effective way to solve food safety problems.In this paper,lactic acid bacteria with bacteriostasis function were mainly selected from five dairy products hand-made by Xinjiang herders.Three strains of Lactobacillus plantarum P1,S11 and M7 with outstanding antibacterial activity were obtained.It was also found that Lactobacillus plantarum P1 had a significant adsorption effect on the environmental hormone dibutyl phthalate(DBP).The first objective of this study was to develop a new natural food bacteriostat.We analyzed the fermentation broths of Lactobacillus plantarum P1,S11 and M7 and found that organic acids were the main bacteriostatic substances.The results of HPLC analysis showed that the organic acids secreted by the three strains mainly contained tartaric acid,malic acid,lactic acid,citric acid and acetic acid.Three kinds of organic acid bacteriostatic agents P1-1,S11-1 and M7-1 were arranged according to the ratio of organic acid in the fermentation broth of the three strains.These three new bacteriostatic agents have outstanding antibacterial activity and S11-1 had the strongest antibacterial activity among them against Salmonella,and the diameter of the inhibition zone in the plate reached 12.2 mm.The second objective of this study is to use biosorption technology to solve the problem of environmental hormone DBP residues in food.In the aqueous phase system,the adsorption rate of Lactobacillus plantarum P1 to 10 mg/mL DBP reached 62%,and this adsorption capacity remained stable in the acid-base solution.The study found that the adsorption sites of P1 cells to DBP were cell wall and extracellular polysaccharide,and the adsorption force was ion force.