Jing Guo-Xing, Tao Neng-Guo, Jia Lei, Zhou Hai-En
School of Chemical Engineering, Xiangtan University, Xiangtan, 411105, People's Republic of China.
Bot Stud. 2015 Dec;56(1):35. doi: 10.1186/s40529-015-0116-4. Epub 2015 Dec 13.
Plant essential oils could act effectively against postharvest diseases, α-terpineol, a typical terpenoid of plant essential oils, exhibited strong antifungal activity in against Penicillium italicum, but the possible action mechanism remains undetermined. In present study, α-terpineol was evaluated for antibacterial activity against Penicillium digitatum along with the mode of their antibacterial action.
The results showed that mycelial growth of P. digitatum was strongly inhibited by α-terpineol, with the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of 2.00 and 8.00 µl/ml, respectively. Scanning electron microscopy observation revealed that α-terpineol obviously altered the morphology of P. digitatum hyphae by causing the loss of cytoplasm and distortion of mycelia. A rapid increase in the membrane permeability of P. digitatum was observed after treated with MIC or MFC of α-terpineol, evidenced by the release of cell constituents, the extracellular conductivity, and the extracellular pH. In addition, α-terpineol apparently induced a decrease in total lipid contents of P. digitatum cells, indicating the destruction of cell membrane structures after treatment.
Based on our study, α-terpineol might affect the cell wall synthesis and lead to the disruption of cell wall. The cell wall disruption affected fungal morphogenesis, the integrity of membrane and leakage of intracellular components, these results suggested that α-terpineol treatment inhibited the growth of P. digitatum.
植物精油可有效防治采后病害，α-萜品醇作为植物精油的典型萜类化合物，对意大利青霉表现出较强的抗真菌活性，但其可能的作用机制尚不清楚。本研究对α-萜品醇对指状青霉的抗菌活性及其抗菌作用方式进行了评价。
结果表明，α-萜品醇对指状青霉的菌丝生长有强烈抑制作用，其最低抑菌浓度（MIC）和最低杀菌浓度（MFC）分别为2.00和8.00 μl/ml。扫描电子显微镜观察显示，α-萜品醇通过导致细胞质流失和菌丝体变形，明显改变了指状青霉菌丝的形态。用α-萜品醇的MIC或MFC处理后，观察到指状青霉的膜通透性迅速增加，细胞成分释放、细胞外电导率和细胞外pH值均证明了这一点。此外，α-萜品醇明显导致指状青霉细胞总脂质含量下降，表明处理后细胞膜结构遭到破坏。
基于我们的研究，α-萜品醇可能影响细胞壁合成并导致细胞壁破坏。细胞壁破坏影响真菌形态发生、膜的完整性和细胞内成分泄漏，这些结果表明α-萜品醇处理抑制了指状青霉的生长。
