บทคัดย่องานวิจัย

หมวดหมู่ : ฐานข้อมูลงานวิจัย

Reduction of Aspergillus carbonarius growth and ochratoxin A biosynthesis in grapes by biocontrol yeasts and an antifungal natural compound

Favilla M.; Altomare C.; Pascale M. and Ricelli A.

5th International Postharvest Symposium . Volume of Abstract . Verona, Italy 6-11 June 2004, p.114

2004

บทคัดย่อ

Reduction of Aspergillus carbonarius growth and ochratoxin A biosynthesis in grapes by biocontrol yeasts and an antifungal natural compound Aspergillus carbonarius infection of grapes is emerging as a major problem in th eMediterranean Area. Infections may lead to the occurrence of the carcinogenic, teratogenic, and mutagenic mycotoxin ochratoxin A (Ota) in wine. Preventing treatments against A. carbonarius are the o­nly strategy capable of wvercoming contamination of the harvested grapes and wine. Biological control of plant diseases offers many benefits in disease management, because it is environmentally non hazardous and it does not induce pathogen resistance. The aim of this study was to investigate the capability of three biocontrol agents (Rhodotorula glutinis, Pichia guilliermondii, Candida oleophila) and of furapyrone (FS), a natural antifungal compound, to inhibit A. carbonarius o­n grapes and OTA biosynthesis.

Artificially wounded grapes (cv. Negroamaro) were inoculated with a toxigenic strain of A. carbonarius, and treated with a solution of FP at the concentration of 50 or 100 mg L-1, with the biocontrol yeasts, or a combination of FP at 50 mg L-1 and yeasts(n = 4 replicates per treatment). Grapes were incubated in moist chambers at 25°C in the dark for 10 days.

A significant inhibition of fungal growth was observed in the 100 mg L-1 FP treated grapes. Ergosterol content was 72% less than control and conidiation was almost completely inhibited. This treatment also resulted in a 99% reduction of OTA content. At the dose of 50 mg mL-1, FP significantly reduced both the viable mould count (by 99%) and Ota production (by 79%), but not the production of fungal biomass. Among the biocontrol yeasts, o­nly C. oleophila and P. guilliermondii were effective, resulting in a reduction of both production of conidia (94% and 96% of inhibition, respectively) and OTA biosynthesis (12% and 18% of reduction, respectively). However, neither additive nor synergistic effect was observed when biocontrol yeasts were applied along with 50 mg L-1 of FP.