I. Introduction 330 II. Choice of Inexpensive Raw Materials Used in Biosurfactant

Production 339 A. Carbon source 339 B. Nitrogen source 345 C. Phosphate source 348 D. Metals 348 E. Other components 349

III. Increase of Biosurfactant Yield 350 A. Biosynthesis control 350 B. Screening of overproducers 352 C. Alteration of the genetics of producers 354

IV. Optimization of the Fermentation Process 355 A. Reactor design 355 B. Fermentor operating conditions 358 C. Recycling of spent medium 359 D. Production scale 359

V. Product Recovery 360 A. Factors involved in biosurfactant recovery 360 B. Classical recovery methods 361 C. In situ methods 362 D. Newly developed recovery methods 363

VI. Biosurfactant Properties A. Surfactant efficiency and effectiveness B. Other biosurfactant properties

VII. Conclusions


365 365 366

Surfactants are used as adhesives, flocculating, wetting, and foaming agents, deemulsifiers, and penetrants. They include both lower priced commodity and specialty chemicals. Sales of surfactants grow approximately 2%-3% per year [1]. Petroleum industries are the major users. Other uses include pulp and sludgedewatering and slurry stabilization (Table 1). Desirable characteristics include solubility, surface tension reduction, low critical micelle concentrations, detergency power, wetting ability, and foaming capacity [2]. No surfactant can do all these functions equally well. Therefore, a wide variety of surfactants exists and the demand is high.