Isolation and Antifungal and Antioomycete Activities of Aerugine Produced by Pseudomonas fluorescens Strain MM-B16

Abstract

The bacterial strain MM-B16, which showed strong antifungal and antioomycete activity against some plant pathogens, was isolated from a mountain forest soil in Korea. Based on the physiological and biochemical characteristics and 16S ribosomal DNA sequence analysis, the bacterial strain MM-B16 was identical to Pseudomonas fluorescens. An antibiotic active against Colletotrichum orbiculare and Phytophthora capsici in vitro and in vivo was isolated from the culture filtrates of P. fluorescens strain MM-B16 using various chromatographic procedures. The molecular formula of the antibiotic was deduced to be C 10 H 11 NO 2 S (M ؉ , m/z 209.0513) by analysis of electron impact mass spectral data. Based on the nuclear magnetic resonance and infrared spectral data, the antibiotic was confirmed to have the structure of a thiazoline derivative, aerugine [4-hydroxymethyl-2-(2-hydroxyphenyl)-2-thiazoline]. C. orbiculare, P. capsici, and Pythium ultimum were most sensitive to aerugine (MICs for these organisms were approximately 10 g ml ؊1 ). However, no antimicrobial activity was found against yeasts and bacteria even at concentrations of more than 100 g ml ؊1 . Treatment with aerugine exhibited a significantly high protective activity against development of phytophthora disease on pepper and anthracnose on cucumber. However, the control efficacy of aerugine against the diseases was in general somewhat less than that of the commercial fungicides metalaxyl and chlorothalonil. This is the first study to isolate aerugine from P. fluorescens and demonstrate its in vitro and in vivo antifungal and antioomycete activities against C. orbiculare and P. capsici.

Isolation, purification and characterization of an antifungal molecule produced by Bacillus licheniformis BC98, and its effect on phytopathogen Magnaporthe grisea

“…1998) have been described as producers of effective biological control agents antagonistic to many fungal phytopathogens. However, data pertaining to the antagonistic activity of bacteria against M. grisea , a potent rice pathogen, are still restricted to only a few strains of Pseudomonas (Lee et al. 2003), Streptomyces (Gomes et al.…”

Detection of Phenazines from UPMP3 Strain of Pseudomonas aeruginosa and its Antagonistic Effects against Ganoderma boninense

“…P. aeruginosa ID 4365 produced PCA which showed inhibitory activities against Aspergillus -niger NCIM1025, Fusarium oxysporum NCIM1008, Sclerotium rolfsii NCIM 1084, Colletotrichum falcatum and several other phytopathogens (Makarand et al, 2007). Lee et al (2003) was also reported that minimal inhibitory concentration of PCA produced by this strain for S. rolfsii NCIM 1084 was found to be 29 mg/L. The inhibitory action of pyocyanin was proposed that, during respiration, pyocyanin becomes reduced and univalently reduces oxygen to the toxic superoxide radical.…”

A Novel Reporter System for Molecular Imaging and High‐Throughput Screening of Anticancer Drugs

“…1), was purified and chemically characterized from the culture filtrate of the actinomycete strain VK‐A9 by analysing NMR and MS spectral data 13. Various antifungal compounds such as manumycin‐type antibiotic SW‐B,14 fistupyrone,15 phenazine‐1‐carboxylic acid,16 aerugine,17 A90931a18 and staurosporine19 isolated from soil microorganisms have been demonstrated to have potent antifungal or antioomycete activity for the control of economically important plant diseases.…”