Screening and Identification of Lactic Acid Bacteria Degrading Patulin and Its Degrading Characteristics

Objective:To screen and identify lactic acid bacteria strains with degrading patulin ability and reveal theirs characteristics. Methods:Two strains of lactic acid bacteria isolated from Qinghai pickle were activated and co-cultured with patulin,and the contents of patulin in the system during co-cultivation was detected by high performance liquid chromatography(HPLC). The strain with high patulin degradation ability was selected. The taxonomic evolutionary status of the strain was determined based on the morphological observation and homology alignment of 16S rDNA sequences. The viable cells,intracellular substances,extracellular metabolites,and cell walls of the strain were further prepared and co-cultured with patulin. The HPLC was used to study the patulin degradation effects of the above components to reveal the characteristics of the strain degrading patulin. Results:YZU02 was screened from two strains of lactic acid bacteria isolated from Qinghai pickle,which could degrade patulin efficiently. Microbial morphology observation and 16S rDNA sequencing alignment showed that YZU02 strain was Lactobacillus plantarum. The viable cells of YZU02 could reduce patulin from 10.87 μg/mL to 2.94 μg/mL within 36 h. The intracellular substances of YZU02,intracellular substances of YZU02 stimulated by patulin and extracellular metabolites of YZU02 had almost no degradation effect on patulin. It was speculated that the removal of platin by YZU02 was not biodegradation. The YZU02 cell wall could reduce the content of patulin from 10.84 μg/mL to 5.10 μg/mL. Conclusion:Lactobacillus plantarum YZU02 could remove patulin through its cell wall adsorption. The removal efficiency could reach 72.95% for patulin up to 10.87 μg/mL within 36 h. It would has great application value in the prevention and treatment of patulin contamination.