Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, India.
Centre for Nanotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, India.
J Appl Microbiol. 2021 Jul;131(1):105-123. doi: 10.1111/jam.14940. Epub 2020 Dec 9.
Candida-associated fungal infections are prevalent in hospitalized and immune-compromised patients. Their biofilm architecture and high rate of antifungal resistance make treatment challenging. Eucalyptol (EPTL), a monoterpene majorly present in the essential oil of eucalyptus is well known for curing respiratory infections. Hence, the present study investigated the anti-biofilm efficacy of EPTL against the laboratory strains and clinical isolates of Candida to delineate its mode of action.
The effect of EPTL on the viability, biofilm formation, and mature biofilm of Candida strains was studied. Furthermore, its effect on cell cycle arrest, mitochondrial membrane potential (MMP), ROS generation, germ tube formation, ergosterol content and transcriptional expression of selected genes was also investigated.
EPTL exhibited anti-biofilm activity against mature and developing biofilm of Candida albicans and Candida glabrata along with their clinical isolates. The biochemical components and enzyme activity were differentially modulated in EPTL-treated biofilm extracellular matrix. EPTL generated ROS and arrested cell cycle at the G /S phase in both the species, while altered MMP was recorded in C. glabrata. Transcriptional analysis evidenced for differential gene expression of selected ABC transporters, secreted hydrolytic enzymes, and cell wall biogenesis in C. albicans/C. glabrata upon treating with EPTL.
The current data on anti-biofilm activity of EPTL establish its candidacy for drug development or as an adjuvant with existing antifungal formulations.
Present investigation elucidates the mode of action of Eucalyptol as antifungal agent and would stand as a candidate for management of topical fungal infection.
念珠菌相关真菌感染在住院患者和免疫功能低下患者中较为普遍。其生物膜结构和高抗真菌耐药率使得治疗具有挑战性。桉树脑(EPTL)是一种主要存在于桉树精油中的单萜烯,以治疗呼吸道感染而闻名。因此,本研究调查了 EPTL 对实验室株和临床分离株念珠菌的抗生物膜作用,以阐明其作用机制。
研究了 EPTL 对念珠菌菌株活力、生物膜形成和成熟生物膜的影响。此外,还研究了其对细胞周期停滞、线粒体膜电位(MMP)、ROS 生成、芽管形成、麦角固醇含量和选定基因转录表达的影响。
EPTL 对白色念珠菌和光滑念珠菌及其临床分离株的成熟和发育生物膜均表现出抗生物膜活性。EPTL 处理的生物膜细胞外基质中的生化成分和酶活性发生了差异调节。EPTL 在两种物种中均产生 ROS 并使细胞周期在 G/S 期停滞,而 MMP 在 C. glabrata 中发生改变。转录分析表明,EPTL 处理后,选定的 ABC 转运蛋白、分泌水解酶和细胞壁生物合成的基因在 C. albicans/C. glabrata 中表达不同。
EPTL 的抗生物膜活性的现有数据表明其具有作为药物开发或与现有抗真菌制剂联合使用的候选物。
本研究阐明了桉树脑作为抗真菌剂的作用机制,将成为管理局部真菌感染的候选药物。