Simionato Ane S, Navarro Miguel O P, de Jesus Maria L A, Barazetti André R, da Silva Caroline S, Simões Glenda C, Balbi-Peña Maria I, de Mello João C P, Panagio Luciano A, de Almeida Ricardo S C, Andrade Galdino, de Oliveira Admilton G
Laboratório de Ecologia Microbiana, Departamento de Microbiologia, Universidade Estadual de LondrinaLondrina, Brazil.
Laboratório de Fitopatologia, Departamento de Agronomia, Universidade Estadual de LondrinaLondrina, Brazil.
Front Microbiol. 2017 Jun 14;8:1102. doi: 10.3389/fmicb.2017.01102. eCollection 2017.
One of the most important postharvest plant pathogens that affect strawberries, grapes and tomatoes is , known as gray mold. The fungus remains in latent form until spore germination conditions are good, making infection control difficult, causing great losses in the whole production chain. This study aimed to purify and identify phenazine-1-carboxylic acid (PCA) produced by the LV strain and to determine its antifungal activity against . The compounds produced were extracted with dichloromethane and passed through a chromatographic process. The purity level of PCA was determined by reversed-phase high-performance liquid chromatography semi-preparative. The structure of PCA was confirmed by nuclear magnetic resonance and electrospray ionization mass spectrometry. Antifungal activity was determined by the dry paper disk and minimum inhibitory concentration (MIC) methods and identified by scanning electron microscopy and confocal microscopy. The results showed that PCA inhibited mycelial growth, where MIC was 25 μg mL. Microscopic analysis revealed a reduction in exopolysaccharide (EPS) formation, showing distorted and damaged hyphae of . The results suggested that PCA has a high potential in the control of and inhibition of EPS (important virulence factor). This natural compound is a potential alternative to postharvest control of gray mold disease.
影响草莓、葡萄和番茄的最重要的采后植物病原体之一是灰霉病菌，也被称为灰霉病。这种真菌以潜伏形式存在，直到孢子萌发条件适宜，这使得感染控制变得困难，在整个生产链中造成巨大损失。本研究旨在纯化和鉴定LV菌株产生的吩嗪-1-羧酸（PCA），并确定其对灰霉病菌的抗真菌活性。产生的化合物用二氯甲烷萃取并经过色谱过程。PCA的纯度水平通过反相高效液相色谱半制备法测定。PCA的结构通过核磁共振和电喷雾电离质谱法确认。抗真菌活性通过干纸碟法和最低抑菌浓度（MIC）法测定，并通过扫描电子显微镜和共聚焦显微镜鉴定。结果表明，PCA抑制菌丝体生长，MIC为25μg/mL。显微镜分析显示胞外多糖（EPS）形成减少，表明灰霉病菌的菌丝体扭曲且受损。结果表明，PCA在控制灰霉病菌和抑制EPS（重要的致病因子）方面具有很高的潜力。这种天然化合物是采后控制灰霉病的潜在替代品。
