文献类型：期刊文献

英文题名：Isolation and characterization of a biosurfactant producing strain, Brevibacilis brevis HOB1

作者：Haddad, Namir I. A.[1];Wang, Ji[1];Mu, Bozhong[1]

机构：[1]E China Univ Sci & Technol, Coll Chem & Mol Engn, Shanghai 200237, Peoples R China

年份：2008

卷号：35

期号：12

起止页码：1597

外文期刊名：JOURNAL OF INDUSTRIAL MICROBIOLOGY & BIOTECHNOLOGY

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000260837900005)】；

基金：This work was supported by the National Natural Science Foundation of China (No. 50374038), Specialized Research Fund for the Doctoral Program of Higher Education (20030251002) and by the Department of Science and Technology Shanghai (045407017).

语种：英文

外文关键词：Brevibacilis brevis; Biosurfactants; HPLC; Lipopeptides; Surfactin

摘要：Biosurfactant-producing bacteria were isolated from the production water of an oil field. Isolates were screened for biosurfactant production using surface tension test. The highest reduction of surface tension was achieved with a bacterial strain which was identified by 16S rRNA gene sequencing as Brevibacilis brevis HOB1. It has been investigated using different carbon and nitrogen sources. It showed that the strain was able to grow and reduce the surface tension of the broth to 29 mN/m on commercial sugar and maltose, and to 32 mN/m on glucose after 72 h of growth. The maximum amount of biosurfactant was obtained when nitrate ions were supplied as nitrogen source. Biosurfactant produced by Brevibacilis brevis HOB1 was confirmed as a lipopeptide class of biosurfactant using TLC test and mass spectra. Lipopeptide isoforms were isolated from cell-free supernatants by acid-precipitation followed by one step of chromatographic separation on solid-phase ODS C18 column. The separation was confirmed by HPLC and ESI Q-TOF MS spectroscopy. Comparing the mass data obtained and the mass numbers reported for the lipopeptide complexes from other strains, it can be concluded that the major lipopeptide product of Brevibacilis brevis HOB1 is the surfactin isoform. This lipopeptide showed strong antibacterial and antifungal activity. It is a candidate for the biocontrol of pathogens in agriculture and other industries.