文献类型：期刊文献

英文题名：Surfactin isoforms from Bacillus subtilis HSO121:: Separation and characterization

作者：Haddad, Namir I. A.[1,2];Liu, Xiangyang[1,2];Yang, Shizhong[1,2];Mu, Bozhong[1,2]

机构：[1]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]E China Univ Sci & Technol, Inst Appl Chem, Shanghai 200237, Peoples R China

年份：2008

卷号：15

期号：3

起止页码：265

外文期刊名：PROTEIN AND PEPTIDE LETTERS

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000254080000006)】；

语种：英文

摘要：Natural surfactin is a mixture of cyclic lipopeptides built from variants of a heptapeptide and a beta-hydroxy fatty acid. A biosurfactant-producing strain, Bacillus Sabtilis HSO121, was isolated from the production water of an oil field. The strain was able to produce eight surfactin isoforms which have been isolated by acid-precipitation followed by extraction into methanol. A novel procedure for the purification of surfactin was achieved. It consists of a solid-phase extraction on C-18 gel followed by reversed-phase high performance liquid chromatography using Prep. HiQ sil C18W, column. The surfactin isoforms were eluted by linear acetonitrile gradient from 80-100%. The peaks were analyzed by TLC on silica gel, and after acid hydrolysis their amino acid compositions were determined by HPLC analysis. Eight isoforms of surfactin had nearly the same amino acid composition and appeared a single spot in TLC. According to the R-f values with the amino acid composition, these peaks belong to the surfactin group of lipopeptides. Infrared analysis of the purified samples also revealed a pattern similar to that of surfactin. This is a very effective method for isolating and fractionating lipopeptides, of the same or different nature.