ISOLATION AND CHARACTERIZATION OF A SURFACTANT PRODUCED BY BACILLUS-LICHENIFORMIS-86

Surfactant (BL86) was isolated from foam produced during growth of Bacillus licheniformis 86 by acid-precipitation followed by extraction into tetrahydrofuran or methanol. The surfactant is anionic and dissolves in tetrahydrofuran, methanol, chloroform, dichloromethane, xylene, toluene, and alkaline water. The surfactant lowers the surface tension of water to 27 dynes/cm, and achieves the critical micelle concentration with as little as 10-mu-g surfactant/ml. Its interfacial tension can reach 0.36 dynes/cm when measured in 4% sodium chloride against n-hexadecane. The surfactant is stable from pH 4.0 to 13.0, at temperatures ranging from 25 to 120-degrees-C, and in salt solutions ranging from 0 to 30% NaCl. Preliminary analytical results indicate that the surfactant is a mixture of lipopeptides different from previously reported Bacillus produced surfactants.