中文摘要：

After incubation for 6- 30 h,with the rapid increase of bacterial cell number,surface tension of bacterium BS-8 was reduced sharply from 63. 2 m N / m to 39. 4 m N / m. The production of biosurfactants by BS-8 was growth-dependent. Using glucose as the carbon source,bacterium BS-8 was incubated. Based on centrifugation,precipitation and chromogenic reaction of the culture solution,results indicated that the biosurfactants belonged to lipopeptides. The yield of biosurfactants isolated and purified from the culture solution was 0. 58 g / L,and the critical micelle concentration( CMC) was 90 mg / L. Under conditions of p H 4- 9,temperature 20- 70 ℃,Na Cl concentration 1%- 6%,biosurfactants produced by BS-8 exhibited the highest stability.

英文摘要：

After incubation for 6 -30 h, with the rapid increase of bacterial cell number, surface tension of bacterium BS-8 was reduced sharply from 63.2 mN/m to 39.4 mN/m. The production of biosurfactants by BS-8 was growth-dependent. Using glucose as the carbon source, bacterium BS-8 was incubated. Based on centrifugation, precipitation and chromogenie reaction of the culture solution, results indicated that the biosurfactants belonged to lipopeptides. The yield of biosurfaetants isolated and purified from the culture solution was 0.58 g/L, and the critical micelle concentration （CMC） was 90 mg,/L. Under conditions of pH 4 -9, tem- perature 20 -70 ℃, NaCl concentration 1% -6%, biosurfactants predueed by BS-8 exhibited the highest stability.