Division of Materials and Manufacturing Science, Osaka University, Suita, Japan.
Department of Chemistry, Nara Women's University, Nara, Japan.
PLoS One. 2024 Aug 27;19(8):e0308383. doi: 10.1371/journal.pone.0308383. eCollection 2024.
Microbial volatile organic compounds (VOCs) emitted from fungi are known as their secondary metabolites from environmental sources. However, their physiological roles remain to be unclear. Even though the roles are still unknown, VOCs are deliberately released to convey information to both homologous and non-homologous organisms. We investigated the effects of single VOCs (hexanal, benzaldehyde, heptanal, 2-ethyl-1-hexanol, 3-octanone, 2-undecanone, 3-octanol, 2-Phenylethanol, 2-phenyl-2-propanol, phenylbenzaldehyde, 2-pentadecanone, β-trans-bergamotene, β-bisabolene, 2-methyl-5 -(1-methylethyl)pyrazine) on the fungal growth. In parallel, application of the co-culturing system in a growth chamber allowed free gas and VOCs exchange between emitter colonies of Fusarium solani and Aspergillus fumigatus, or between colonies of different growth stages of the same species. Distinct self-inhibition occurred by the emitters of fungal growing colonies against receiver ones on the stage of conidial germination or against the younger colonies at an earlier stage in both fungi. Similarly, the phenomenon of allelopathy appeared to work between growing colonies of F. solani and the germinating conidia or young colonies of A. fumigatus or vice versa. Solid phase microextraction-gas chromatography/mass spectrometry revealed VOCs compounds of each fungi. In F. solani, hexanal and benzaldehyde appeared to be significant inhibitors for colony growth. Benzaldehyde inhibited filamentous growth but not conidial germination. In A. fumigatus, heptanal seemed to be an equivalent effector. The inhibitory effect of benzaldehyde was more distinct on the A. fumigatus conidial germination than its filamentous growth.
真菌释放的微生物挥发性有机化合物 (VOCs) 被称为其环境来源的次生代谢物。然而，它们的生理作用仍然不清楚。尽管作用仍不清楚，但 VOCs 是故意释放的，以向同源和非同源生物传递信息。我们研究了单一 VOCs（己醛、苯甲醛、庚醛、2-乙基-1-己醇、3-辛酮、2-十一烷酮、3-辛醇、2-苯乙醇、2-苯-2-丙醇、苯甲醛、2-十五烷酮、β-反式佛手柑烯、β-双环大根香叶烯、2-甲基-5-(1-甲基乙基)吡嗪）对真菌生长的影响。同时，在生长室中应用共培养系统允许茄病镰刀菌和烟曲霉的发射菌菌落之间自由气体和 VOCs 交换，或允许同一物种不同生长阶段的菌落之间自由气体和 VOCs 交换。在真菌分生孢子萌发阶段或在同一真菌的早期阶段，生长菌落的发射器对接收者自抑作用明显，而且这种现象在两种真菌中都存在。同样，在茄病镰刀菌和萌发分生孢子或年轻菌落的生长菌落之间，或者在烟曲霉的生长菌落和萌发分生孢子或年轻菌落之间，似乎也出现了化感作用。固相微萃取-气相色谱/质谱联用仪揭示了每种真菌的 VOCs 化合物。在茄病镰刀菌中，己醛和苯甲醛似乎是对菌落生长的显著抑制剂。苯甲醛抑制丝状生长，但不抑制分生孢子萌发。在烟曲霉中，庚醛似乎是一种等效的效应物。苯甲醛对烟曲霉分生孢子萌发的抑制作用比其丝状生长更为明显。
