title: The mechanism of antifungal action of essential oil from dill (Anethum graveolens L.) on Aspergillus flavus.
abstract: The essential oil extracted from the seeds of dill (Anethum graveolens L.) was demonstrated in this study as a potential source of an eco-friendly antifungal agent. To elucidate the mechanism of the antifungal action further, the effect of the essential oil on the plasma membrane and mitochondria of Aspergillus flavus was investigated. The lesion in the plasma membrane was detected through flow cytometry and further verified through the inhibition of ergosterol synthesis. The essential oil caused morphological changes in the cells of A. flavus and a reduction in the ergosterol quantity. Moreover, mitochondrial membrane potential (MMP), acidification of external medium, and mitochondrial ATPase and dehydrogenase activities were detected. The reactive oxygen species (ROS) accumulation was also examined through fluorometric assay. Exposure to dill oil resulted in an elevation of MMP, and in the suppression of the glucose-induced decrease in external pH at 4 µl/ml. Decreased ATPase and dehydrogenase activities in A. flavus cells were also observed in a dose-dependent manner. The above dysfunctions of the mitochondria caused ROS accumulation in A. flavus. A reduction in cell viability was prevented through the addition of L-cysteine, which indicates that ROS is an important mediator of the antifungal action of dill oil. In summary, the antifungal activity of dill oil results from its ability to disrupt the permeability barrier of the plasma membrane and from the mitochondrial dysfunction-induced ROS accumulation in A. flavus.
authors.affiliation: Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, School of Pharmaceutical Sciences, Institute of Traditional Chinese Medicine & Natural Products, Wuhan University, Wuhan, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Tian
authors.forename: Xiaoquan
authors.initials: X
authors.lastname: Ban
authors.forename: Hong
authors.initials: H
authors.lastname: Zeng
authors.forename: Jingsheng
authors.initials: J
authors.lastname: He
authors.forename: Yuxin
authors.initials: Y
authors.lastname: Chen
authors.forename: Youwei
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D028524:Anethum graveolens / Q000737:chemistry*; D000935:Antifungal Agents / Q000302:isolation & purification / Q000494:pharmacology*; D001231:Aspergillus flavus / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D002463:Cell Membrane Permeability / Q000187:drug effects; D017077:Culture Media, Conditioned / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D004875:Ergosterol / Q000378:metabolism; D005434:Flow Cytometry; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D024101:Mitochondrial Proteins / Q000378:metabolism; D009822:Oils, Volatile / Q000302:isolation & purification / Q000494:pharmacology*; D010088:Oxidoreductases / Q000378:metabolism; D010938:Plant Oils / Q000302:isolation & purification / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000935:Antifungal Agents; D017077:Culture Media, Conditioned; D024101:Mitochondrial Proteins; D009822:Oils, Volatile; D010938:Plant Oils; D017382:Reactive Oxygen Species; D010088:Oxidoreductases; D000251:Adenosine Triphosphatases; D004875:Ergosterol