Valero A, Marín S, Ramos A J, Sanchis V
Food Technology Department, University of Lleida, UTPV-CeRTA, Lleida, Spain.
Lett Appl Microbiol. 2007 Aug;45(2):194-9. doi: 10.1111/j.1472-765X.2007.02168.x.
To evaluate the effect of preharvest grape pesticides in Aspergillus section Nigri infection in dehydrating grapes and the final ochratoxin A (OTA) content. Additionally, the effect of coinoculation of moulds frequently isolated from grapes and raisins on Aspergillus section Nigri infection was studied.
Fungicide-treated grapes were inoculated with Aspergillus carbonarius, Aspergillus niger aggregate, Eurotium amstelodami and Penicillium janthinellum in different combinations, then dehydrated by reducing a(w) for 20 days. The percentages of colonized grapes treated with fungicides were, in general, lower, but no differences were observed among fungicides. The untreated grapes always showed higher concentrations of OTA, regardless of the inoculum applied. In general, Chorus was the most effective antifungal treatment in reducing OTA accumulation in grapes during dehydration. Penicillium janthinellum reduced Aspergillus section Nigri colonization and OTA accumulation in grapes during dehydration.
The four preharvest fungicides studied reduced the Aspergillus section Nigri growth and OTA production by A. carbonarius during dehydration of grapes.
The success of these chemical treatments might depend on the mycobiota composition of grapes.
评估采前葡萄农药对脱水葡萄中黑曲霉属感染及最终赭曲霉毒素A（OTA）含量的影响。此外，还研究了从葡萄和葡萄干中频繁分离出的霉菌共接种对黑曲霉属感染的影响。
用不同组合的碳黑曲霉、黑曲霉复合体、阿姆斯特丹散囊菌和展青霉对经过杀菌剂处理的葡萄进行接种，然后通过降低水分活度（aw）进行20天的脱水处理。一般来说，用杀菌剂处理的葡萄的定殖率较低，但不同杀菌剂之间未观察到差异。无论接种何种菌剂，未处理的葡萄中OTA的浓度始终较高。总体而言，Chorus是在葡萄脱水过程中减少OTA积累最有效的抗真菌处理方法。展青霉在葡萄脱水过程中减少了黑曲霉属的定殖和OTA的积累。
所研究的四种采前杀菌剂在葡萄脱水过程中减少了黑曲霉属的生长以及碳黑曲霉产生的OTA。
这些化学处理的成功可能取决于葡萄的真菌群落组成。
