Isolation, Identification and Characterization of Bacillus subtilis CF-3, a Bacterium from Fermented Bean Curd for Controlling Postharvest Diseases of Peach Fruit

Biological control is an alternative to synthetic fungicides to avoid postharvest diseases which limit the storage period and marketing life of fruit and vegetables. Present investigation is focused on the isolation, identification and characterization of Bacillus subtilis CF-3 from fermented bean curd through the analyses of phenotype, physiological and biochemical characterization, 16S rDNA gene sequence based on its biocontrol effect against pathogens (Monilinia fructicola, Cephalothecium, Rhizoctonia and Alternaria) causing peach decay. With treatment of CF-3, the ratio of good fruit was 65% which was higher than 30% in the control group significantly after 36d storage at 10 degrees C and 65% compared with 50% in the control group after 7d storage at 25 degrees C;The optimal growth temperature and pH of CF-3 were 37 degrees C and 8;The results of antimicrobial stability indicated that CF-3's antibiotics had good UV, pH and thermal stability (except at 121 degrees C). Findings of the present study suggested that the antifungal properties of CF-3 may have a potential to be developed as fungicide which can contribute to the postharvest preservation of peach fruit and provide a theoretical basis for the further study of biological control.