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Updated: Jun 22, 2026

Isolation and Chemical Characterization of Lipid A from Gram-negative Bacteria
Published on: September 16, 2013
Isolation and characterization of lipopeptide antibiotics produced by Bacillus subtilis
1Key Laboratory of Ion Beam Bioengineering, Chinese Academy of Sciences, Hefei, Anhui, China.
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.
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