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，用于防治真菌污染。生姜（Zingiber officinale）精油（Ginger Essential Oil, GEO）已知具备抗真菌及抗黄曲霉毒素特性，但目前尚未有关于其作为原位熏蒸剂应用的研究。本研究旨在评估生姜精油作为熏蒸剂，对储粮玉米籽粒中黄曲霉（Aspergillus flavus）的防控效果。经气相色谱-质谱联用（Gas Chromatography-Mass Spectrometry）与核磁共振（Nuclear Magnetic Resonance）表征，该精油的主要成分为α-姜烯（23.85%）与香叶醛（14.16%）。研究中将浓度为5~50 µg/g的生姜精油作为熏蒸剂施用于辐照处理后的玉米籽粒，并将其防控效果与传统用于种子处理的合成抗真菌剂多菌灵（carbendazim）和福美双（thiram）进行对比。经原位（玉米籽粒）试验证实，生姜精油对黄曲霉的抗真菌活性呈剂量依赖性。当浓度为25和50 µg/g时，生姜精油可抑制黄曲霉毒素的生成，并有效控制真菌增殖。因此，生姜精油可作为一种高效低毒的替代方案，用于储粮玉米籽粒中黄曲霉的天然防控，以取代传统化学防治手段。