Bamboo leaf flavonoid enhances the control effect of Pichia caribbica against Penicillium expansum growth and patulin accumulation in apples

Patulin (PAT) mainly produced by Penicillium expansum is a very problematic mycotoxin, and its presence is often reported in different foods and food products. The prevention of these products from initial contamination and/or degradation is therefore of foremost importance in protecting consumer health. In this report, Pichia caribbica (1 x 10(8) cells mL(-1)) antagonistic yeasts incorporated with bamboo leaf flavonoid (0.01% w/v) were assessed for PAT degradation capabilities in in-vitro and in-vivo. Also the effects of treatments on wound lesion diameter, lignification and pH level were investigated. Clearly, the combined biocontrol agent (P. caribbica and bamboo leaf flavonoid) had the ability to degrade PAT in vitro with undetected level at 96 h of incubation in NYDB media. In apple fruits, PAT accumulation was significantly lower at 20 d (at 20 degrees C) of storage. Wound lignification was significantly enhanced from 0.31 to 0.27 after 15 d of storage, whereas pH was modified (> 4.0) in host; which might lead to an increase in PAT breakdown. P. caribbica combined with bamboo leaf flavonoid could be a promising biocontrol agent for PAT degradation processes in apple fruits.