Background: The influence of adding trehalose to the culture medium on the efficacy of Pichia caribbica (JSU-1) in controlling post-harvest grey mould and blue mould decay of apples and the possible mechanisms involved were investigated.
Results: The antagonistic activity of P. caribbica harvested from nutrient yeast dextrose broth (NYDB) amended with trehalose at 5 mg mL(-1) to post-harvest grey mould and blue mould decay was improved greatly compared with that without trehalose. The intracellular trehalose content of P. caribbica harvested from NYDB amended with trehalose at 5 mg mL(-1) was higher than that of P. caribbica harvested from NYDB. The population of P. caribbica could rapidly colonise and grow in apple wounds. Moreover, the application of P. caribbica cultivated in the culture medium of the trehalose supplement (5 mg mL(-1) ) induced higher polyphenoloxidase (PPO) and peroxidase (POD) activity of apples compared with that cultivated by P. caribbica in the NYDB. SEM results suggested that P. caribbica harvested from NYDB amended with trehalose at 5 mg mL(-1) showed stronger inhibition efficacy to Botrytis cinerea than P. caribbica harvested from NYDB.
Conclusion: The antagonistic activity of P. caribbica can be enhanced by adding trehalose to the medium.
Keywords: Pichia caribbica; antagonistic activity; apples; blue mould decay; grey mould decay; possible mechanisms; trehalose.
© 2012 Society of Chemical Industry.