School of Biological Engineering, Henan University of Technology, 100 Lianhua Street, Zhengzhou, 450001, People's Republic of China.
Henan Provincial Key Laboratory of Biological Processing and Nutritional Function of Wheat, Zhengzhou, 450001, People's Republic of China.
Appl Microbiol Biotechnol. 2022 Aug;106(13-16):5179-5196. doi: 10.1007/s00253-022-12049-z. Epub 2022 Jul 2.
The exploitation of active ingredients from plant volatile organic compounds as natural gaseous fungicides shows remarkable potential for controlling fungal decay in postharvest agroproducts. Although 1-octanol is a common component of cereal volatiles, its antifungal potency against spoilage fungi in postharvest grains remains unclear. In this study, we studied the effectiveness of 1-octanol against Aspergillus flavus growth in postharvest grains and its mechanisms of action. 1-Octanol vapor and liquid contact dose-dependently inhibited A. flavus spore germination and mycelial growth at a low concentration. The simulated storage experiment demonstrated that 300 μL/L of 1-octanol vapor completely controlled A. flavus growth in wheat, corn, and paddy grains with 20% moisture content. 1-Octanol treatment irreversibly damaged the conidial and mycelial morphology of A. flavus and caused electrolyte leakage due to reduced plasma membrane integrity. It induced apoptosis along with morphological abnormalities, phosphatidylserine externalization, mitochondrial membrane potential depolarization, intracellular reactive oxygen species accumulation, and DNA fragmentation in A. flavus cells. Metabolomic analysis revealed that 1-octanol treatment disrupted the biosynthesis of unsaturated fatty acids, ATP-binding cassette transporters, amino acid metabolism, and glycerophospholipid metabolism. This study demonstrated the promising application potential of 1-octanol as a biofumigant for preventing fungal spoilage of postharvest cereal grains. KEY POINTS: • (1) 1-Octanol inhibits Aspergillus flavus growth in the vapor phase and liquid contact; • (2) 1-Octanol damages membrane integrity and induces apoptosis of A. flavus; • (3) Metabolomic changes in A. flavus mycelia were analyzed after 1-octanol treatment.
植物挥发性有机化合物活性成分的开发利用作为天然气态杀菌剂，在控制采后农产品真菌腐烂方面具有显著潜力。虽然 1-辛醇是谷物挥发物的常见成分，但它对采后谷物中腐败真菌的抗真菌效力尚不清楚。在本研究中，我们研究了 1-辛醇对采后谷物中黄曲霉生长的有效性及其作用机制。1-辛醇蒸气和液体接触以低浓度剂量依赖性地抑制黄曲霉孢子萌发和菌丝生长。模拟储存实验表明，300μL/L 的 1-辛醇蒸气完全控制了含水量为 20%的小麦、玉米和稻谷中黄曲霉的生长。1-辛醇处理不可逆地破坏了黄曲霉的分生孢子和菌丝形态，并由于质膜完整性降低而导致电解质泄漏。它诱导了黄曲霉细胞的细胞凋亡以及形态异常、磷脂酰丝氨酸外翻、线粒体膜电位去极化、细胞内活性氧物质积累和 DNA 片段化。代谢组学分析显示，1-辛醇处理破坏了不饱和脂肪酸、ABC 转运蛋白、氨基酸代谢和甘油磷脂代谢的生物合成。本研究表明 1-辛醇作为一种生物熏蒸剂防止采后谷类真菌腐烂具有广阔的应用潜力。关键点：（1）1-辛醇抑制黄曲霉在蒸气相和液体接触中的生长；（2）1-辛醇破坏细胞膜完整性并诱导黄曲霉凋亡；（3）分析了 1-辛醇处理后黄曲霉菌丝的代谢变化。
