Isolation And Identification Of Biosurfactant And The Producing Bacterium

Biosurfactant is an environmentally friend surfactant which is characterized by highsurface activity, high salt and alkali resistance, and it is believed to be of greatapplication value in the future.Aiming at the biosurfactant, a high-thoughout method for biosurfactant producingbacteria screening has been established and a strain namely JS02-7picked and it isidentified as Baccillus sbutils. Experimental study of the biosurfactant producton hasbeen carried out on fermentation condition and the yield is as high as480mg/L underthe optimal conditions. With the help of thin layer chromatography, amino acid analysisand infrared spectroscopy, the biosurfactant produced by JS02-7is identified to belipopeptide.The method for isolation of lipopeptide has been established which is characterized bythe combination of normal pressure column chromatography and preparative highperformance liquid chromatography. With this method, lipopeptdie compound has beenobtained from the broth of Bacillus subtilis JS02-7with a purity of96%.Based on ESI, Q-TOF, MS/MS ect, the method for lipopeptide identification have beenset up and eight lipopetide compounds in the broth of Bacillus subtilis JS02-7have beenidentified with molecular weights of1007,1021,1021,1035,1035,1035,1063and1049,of which the main compounds are comprised of a peptide chain ofN-Glu-Leu-Leu-Val-Asp-Leu-Leu-C and a hydroxy fatty acid chain of iso C₁2, iso C₁3,anteiso C₁3, iso C₁4, n C₁4, iso C₁5, anteiso C₁5, n C₁5respectively. Thesecompounds are all the ring lipopeptide.