AIMS: Antibiotics from Bacillus subtilis JA show strong pathogen inhibition ability, which has potential market application; yet, the composition of these antibiotics has not been elucidated. The aim of this paper is to isolate and identify these antibiotics. METHODS AND RESULTS: The antagonistic activity of JA was tested in vitro; it exhibited strong inhibition against some important phytopathogens and postharvest pathogens. Crude antibiotic production was extracted with methanol from the precipitate by adding 6 mol l(-1) HCl to the bacillus-free culture broth. The crude extract was run on Diamonsil C18 column (5 microm, 250 x 4.6 mm) in HPLC system to separate the antibiotics. Major antibiotics were classified into three lipopeptide families according to electrospray ionization-mass spectrometry analysis. Subsequently, the classification of antibiotics was confirmed with typical collision-induced dissociation fragments. CONCLUSIONS: Three kinds of antibiotics were isolated from B. subtilis JA and were identified to the lipopeptide families, surfactin, iturin and fengycin. These compounds could function as biocontrol agents against a large spectrum of pathogens. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provided a reliable and rapid method for isolation and structural characterization of lipopeptide antibiotics from B. subtilis.
AIMS: Antibiotics from Bacillus subtilisJA show strong pathogen inhibition ability, which has potential market application; yet, the composition of these antibiotics has not been elucidated. The aim of this paper is to isolate and identify these antibiotics. METHODS AND RESULTS: The antagonistic activity of JA was tested in vitro; it exhibited strong inhibition against some important phytopathogens and postharvest pathogens. Crude antibiotic production was extracted with methanol from the precipitate by adding 6 mol l(-1) HCl to the bacillus-free culture broth. The crude extract was run on Diamonsil C18 column (5 microm, 250 x 4.6 mm) in HPLC system to separate the antibiotics. Major antibiotics were classified into three lipopeptide families according to electrospray ionization-mass spectrometry analysis. Subsequently, the classification of antibiotics was confirmed with typical collision-induced dissociation fragments. CONCLUSIONS: Three kinds of antibiotics were isolated from B. subtilisJA and were identified to the lipopeptide families, surfactin, iturin and fengycin. These compounds could function as biocontrol agents against a large spectrum of pathogens. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provided a reliable and rapid method for isolation and structural characterization of lipopeptide antibiotics from B. subtilis.
Authors: Gul Shad Ali; Ashraf S A El-Sayed; Jaimin S Patel; Kari B Green; Mohammad Ali; Mary Brennan; David Norman Journal: Appl Environ Microbiol Date: 2015-10-30 Impact factor: 4.792
Authors: Inès Mnif; Ariadna Grau-Campistany; Jonathan Coronel-León; Inès Hammami; Mohamed Ali Triki; Angeles Manresa; Dhouha Ghribi Journal: Environ Sci Pollut Res Int Date: 2015-12-09 Impact factor: 4.223