Screening and Identification of a Lactic acid bacteria Strain With Lychee Fresh-keeping Function

An antagonistic bacteria from litchi fermentation medium,and the inhibitory effects of antagonism on Peronophythora litchii,Colletotrichum gloeosporioides,polyphenol oxidase(PPO) and peroxidase(POD) were studied.A strain was isolated by plating method,and the improved agar diffusion method and plate confrontation method were used to detect the effect of this strain on Colletotrichum gloeosporioidesand Peronophythora litchi,respectively.The activity of PPO and POD were determined by oxophenic acid and guaiacol as substrate.Results showed that the inhibition zone radius of fermentation broth antagonize Penorophythora litchi was 1.5 cm and Colletotrichum gloeosporioides was 0.75 cm,and the inhibition rate of crude metabolites on litchi peel PPO was close to 60%.Crude metabolites and cell homogenates on POD was 58.8% and 51.4%,respectively.This isolation was identified as a strain of lactobacillus plantarum according to the results of morphological characteristics,physiological and biochemical characteristic,the 16s rDNA analysis and phylogenetic tree construction,which had a good application prospect in litchi bio preservation.