title: Antifungal Activity of Isoliquiritin and Its Inhibitory Effect against Peronophythora litchi Chen through a Membrane Damage Mechanism.
abstract: This study investigated the antifungal activity and potential antifungal mechanism(s) of isoliquiritin against P. litchi Chen, one of the main litchi pathogens. The antifungal activity of isoliquiritin against P. litchi Chen had been proven in a dose-dependent manner through in vitro (mycelial growth and sporangia germination) and in vivo (detached leaf) tests. Results revealed that isoliquiritin exhibited significant antifungal activity against the tested pathogens, especially, P. litchi Chen, with a minimum inhibitory concentration of 27.33 mg/L. The morphology of P. litchi Chen was apparently changed by isoliquiritin through cytoplasm leakage and distortion of mycelia. The cell membrane permeability of the P. litchi Chen increased with the increasing concentration of isoliquiritin, as evidenced by a rise in relative electric conductivity and a decrease in reducing sugar contents. These results indicated that the antifungal effects of isoliquiritin could be explained by a membrane lesion mechanism causing damage to the cell membrane integrity leading to the death of mycelial cells. Taken together, isoliquiritin may be used as a natural alternative to commercial fungicides or a lead compound to develop new fungicides for the control of litchi downy blight.
authors.affiliation: Key Laboratory of Natural Pesticide and Chemical Biology, College of Agriculture, South China Agricultural University, Guangzhou 510642, China. luojianjun@scau.edu.cn.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Luo
authors.affiliation: Key Laboratory of Natural Pesticide and Chemical Biology, College of Agriculture, South China Agricultural University, Guangzhou 510642, China. chibun_li@163.com.
authors.forename: Zhibin
authors.initials: Z
authors.lastname: Li
authors.affiliation: Key Laboratory of Natural Pesticide and Chemical Biology, College of Agriculture, South China Agricultural University, Guangzhou 510642, China. wangjingjing968@126.com.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Key Laboratory of Natural Pesticide and Chemical Biology, College of Agriculture, South China Agricultural University, Guangzhou 510642, China. wengweng@scau.edu.cn.
authors.forename: Qunfang
authors.initials: Q
authors.lastname: Weng
authors.affiliation: Key Laboratory of Natural Pesticide and Chemical Biology, College of Agriculture, South China Agricultural University, Guangzhou 510642, China. csh-happy@163.com.
authors.forename: Shaohua
authors.initials: S
authors.lastname: Chen
authors.affiliation: Key Laboratory of Natural Pesticide and Chemical Biology, College of Agriculture, South China Agricultural University, Guangzhou 510642, China. humy@scau.edu.cn.
authors.forename: Meiying
authors.initials: M
authors.lastname: Hu
mesh_terms: D000935:Antifungal Agents / Q000008:administration & dosage* / Q000737:chemistry; D002462:Cell Membrane / Q000737:chemistry / Q000187:drug effects*; D002599:Chalcone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry; D005638:Fruit / Q000737:chemistry; D005960:Glucosides / Q000008:administration & dosage* / Q000737:chemistry; D025282:Mycelium / Q000187:drug effects / Q000254:growth & development; D010838:Phytophthora / Q000187:drug effects* / Q000472:pathogenicity; D058432:Sporangia / Q000187:drug effects / Q000254:growth & development; D013172:Spores, Fungal / Q000187:drug effects / Q000254:growth & development
chemical_list: D000935:Antifungal Agents; D005960:Glucosides; C098467:neoisoliquiritin; D002599:Chalcone
keywords: Peronophythora litchi Chen; SEM; antifungal; isoliquiritin; mechanism