Antifungal activity and inhibition of aflatoxins production by Zingiber officinale Roscoe essential oil against Aspergillus flavus in stored maize grains

ABSTRACT: Essential oils are possible alternatives to the use of synthetic pesticides for control of fungal contamination. Ginger (Zingiber officinale) essential oil (GEO) is known for having antifungal and antiaflatoxigenic properties, but its use as a fumigant in situ has not been studied yet. The aim of this study was to evaluate GEO’s effects upon Aspergillus flavus as a fumigant agent in stored maize grains. The main compounds reported in GEO were α-zingiberene (23.85%) and geranial (14.16%), characterized by gas chromatography-mass spectrometry and nuclear magnetic resonance. The GEO was used as a fumigant in irradiated maize grains in concentrations ranging from 5 to 50 µg/g and the resulting effects were compared to a synthetic antifungal agent (carbendazim and thiram), an antifungal traditionally used for seed treatment. The antifungal efficacy of GEO against A. flavus has been proven in a dose-dependent manner through in situ (maize grains) test. The GEO inhibited aflatoxin production at concentrations 25 and 50 µg/g and controlled fungal growth. Therefore, GEO can be used as an effective and non-toxic alternative to conventional treatments in stored maize grains for the natural control of A. flavus.

摘要：精油可作为合成农药的替代方案，用于防控真菌污染。姜（Zingiber officinale）精油（ginger essential oil, GEO）兼具抗真菌与抗黄曲霉毒素特性，但其作为原位熏蒸剂的应用尚未见诸研究。本研究旨在评估GEO作为熏蒸剂对储藏玉米籽粒中黄曲霉（Aspergillus flavus）的作用效果。经气相色谱-质谱联用法（gas chromatography-mass spectrometry, GC-MS）与核磁共振波谱法（nuclear magnetic resonance, NMR）鉴定，GEO的主要成分为α-姜烯（α-zingiberene，占比23.85%）与柠檬醛（geranial，占比14.16%）。本实验以浓度范围为5至50 μg/g的GEO对辐照玉米籽粒进行熏蒸处理，并将其防控效果与传统用于种子处理的合成抗真菌药剂（多菌灵与福美双）进行对比。经原位（玉米籽粒）试验证实，GEO对黄曲霉的抗真菌活性呈剂量依赖性；当浓度为25 μg/g与50 μg/g时，GEO可抑制黄曲霉毒素生成并控制真菌增殖。因此，GEO可作为高效无毒的替代方案，应用于储藏玉米籽粒的常规处理，实现对黄曲霉的自然防控。