School of Biological Engineering, Henan University of Technology, 100 Lianhua Street, Zhengzhou, 450001, People's Republic of China.
Appl Microbiol Biotechnol. 2023 Dec;107(23):7213-7230. doi: 10.1007/s00253-023-12791-y. Epub 2023 Sep 21.
Plant volatile compounds have great potential for preventing and controlling fungal spoilage in post-harvest grains. Recently, we have reported the antifungal effects of trans-anethole, the main volatile constituent of the Illicium verum fruit, on Aspergillus flavus. In this study, the inhibitory mechanisms of trans-anethole against the growth of A. flavus mycelia were investigated using transcriptomic and biochemical analyses. Biochemical and transcriptomic changes in A. flavus mycelia were evaluated after exposure to 0.2 μL/mL trans-anethole. Scanning electron microscopy showed that trans-anethole treatment resulted in the surface wrinkling of A. flavus mycelia, and calcofluor white staining confirmed that trans-anethole treatment disrupted the mycelial cell wall structure. Annexin V-fluorescein isothiocyanate/propidium iodide double staining suggested that trans-anethole induced apoptosis in A. flavus mycelia. Reduced mitochondrial membrane potential and DNA damage were observed in trans-anethole-treated A. flavus mycelia using 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-imidacarbocyanine and 4',6-diamidino-2-phenylindole staining, respectively. 2',7'- Dichloro-dihydro-fluorescein diacetate staining and biochemical assays demonstrated that trans-anethole treatment cause the accumulation of reactive oxygen species in the A. flavus mycelia. Transcriptome results showed that 1673 genes were differentially expressed in A. flavus mycelia exposed to trans-anethole, which were mainly associated with multidrug transport, oxidative phosphorylation, citric acid cycle, ribosomes, and cyclic adenosine monophosphate signaling. We propose that trans-anethole can inhibit the growth of A. flavus mycelia by disrupting the cell wall structure, blocking the multidrug transport process, disturbing the citric acid cycle, and inducing apoptosis. This study provides new insights into the inhibitory mechanism of trans-anethole on A. flavus mycelia and will be helpful for the development of natural fungicides. KEY POINTS: • Biochemical analyses of A. flavus mycelia exposed to trans-anethole were performed • Transcriptomic changes in trans-anethole-treated A. flavus mycelia were analyzed • An inhibitory mechanism of trans-anethole on the growth of A. flavus mycelia was proposed.
植物挥发物在防治采后谷物真菌腐败方面具有巨大潜力。最近，我们报道了八角茴香果实中的主要挥发性成分反式茴香脑对黄曲霉的抗真菌作用。在这项研究中，我们通过转录组学和生物化学分析研究了反式茴香脑对黄曲霉菌丝生长的抑制机制。用 0.2 μL/mL 反式茴香脑处理后，评估了黄曲霉菌丝的生物化学和转录组变化。扫描电子显微镜显示，反式茴香脑处理导致黄曲霉菌丝表面起皱，钙荧光白染色证实反式茴香脑处理破坏了菌丝细胞壁结构。 Annexin V-异硫氰酸荧光素/碘化丙啶双重染色表明，反式茴香脑诱导黄曲霉菌丝凋亡。用 5,5',6,6'-四氯-1,1',3,3'-四乙基-间苯二羰花青和 4',6-二脒基-2-苯吲哚染色观察到，线粒体膜电位和 DNA 损伤在反式茴香脑处理的黄曲霉菌丝中降低。2',7'-二氯二氢荧光素二乙酸酯染色和生化分析表明，反式茴香脑处理导致黄曲霉菌丝中活性氧的积累。转录组结果表明，1673 个基因在暴露于反式茴香脑的黄曲霉菌丝中差异表达，这些基因主要与多药转运、氧化磷酸化、柠檬酸循环、核糖体和环腺苷酸信号有关。我们提出，反式茴香脑可以通过破坏细胞壁结构、阻断多药转运过程、扰乱柠檬酸循环和诱导细胞凋亡来抑制黄曲霉菌丝的生长。本研究为反式茴香脑对黄曲霉菌丝的抑制机制提供了新的见解，并将有助于天然杀菌剂的开发。 要点： • 对暴露于反式茴香脑的黄曲霉菌丝进行了生物化学分析 • 分析了反式茴香脑处理的黄曲霉菌丝中转录组的变化 • 提出了反式茴香脑对黄曲霉菌丝生长的抑制机制。
