Área de Fruticultura, Centro de Investigaciones Finca La Orden-Valdesequera (CICYTEX), Autovía Madrid-Lisboa, s/n, 06187 Guadajira, Spain.
Nutrición y Bromatología, Escuela de Ingenierías Agrarias, Instituto Universitario de Recursos Agrarios (INURA), Universidad de Extremadura, Ctra. de Cáceres s/n, 06007 Badajoz, Spain.
Int J Food Microbiol. 2022 Sep 2;376:109772. doi: 10.1016/j.ijfoodmicro.2022.109772. Epub 2022 Jun 1.
Aspergillus flavus and Aspergillus niger are fungi which can contaminate dried figs before and after harvest and consequently produce aflatoxins (AFs) and ochratoxin A (OTA). Many approaches have been applied to minimise the growth of these filamentous fungi, mainly involving the use of synthetic fungicides which are limited due to their negative impact on human health and the environment. In this context, biocontrol is a recent approach that needs to be explored. This study evaluated the potential of three volatile organic compounds (VOCs), octanoic acid (OA), 2-phenylethyl acetate (2PEA) and furfuryl acetate (FA), produced by Hanseniaspora uvarum and Hanseniaspora opuntiae yeasts on the growth, germination, gene expression and production of AFs and OTA by A. flavus M144 and A. niger M185 on dried fig-based agar and the incidence rates in dried figs. Two of the three VOCs evaluated (2PEA and FA) effectively controlled A. flavus M144 and A. niger M185 by using at least amounts of 50 μL (715 μL/L in the headspace) for FA and 100 μL (1430 μL/L in the headspace) for 2PEA in dried figs. One of the mode of actions of both compounds consists in early repressing the expression of genes involved in the biosynthesis of AFs (aflR) and OTA (pks) of A. flavus and A. niger, respectively. The results of this study support the application of 2PEA and FA at the early post-harvest stages of dried figs to control mycotoxin accumulation.
黄曲霉和黑曲霉是真菌，它们可以在收获前后污染干无花果，并因此产生黄曲霉毒素（AFs）和赭曲霉毒素 A（OTA）。已经采用了许多方法来最小化这些丝状真菌的生长，主要涉及使用合成杀真菌剂，但由于其对人类健康和环境的负面影响而受到限制。在这种情况下，生物防治是一种需要探索的新方法。本研究评估了由汉逊酵母产生的三种挥发性有机化合物（VOCs），辛酸（OA），2-苯乙基乙酸酯（2PEA）和糠基乙酸酯（FA），对生长，黄曲霉 M144 和黑曲霉 M185 在基于干无花果的琼脂上的萌发、基因表达以及 AFs 和 OTA 的产生以及干无花果中的发病率的潜在影响。在所评估的三种 VOC 中的两种（2PEA 和 FA）中，使用至少 50μL（715μL/L 在顶空）的 FA 和 100μL（1430μL/L 在顶空）的 2PEA 可有效控制黄曲霉 M144 和黑曲霉 M185。这两种化合物的作用模式之一是早期抑制黄曲霉和黑曲霉中 AFs（aflR）和 OTA（pks）生物合成相关基因的表达。本研究的结果支持在干无花果收获后的早期阶段应用 2PEA 和 FA 来控制真菌毒素的积累。
