Industrial Applications of Some New Microbial Polysaccharides

In recent years, significant progress has been made in discovering and developing new bacterial polysaccharides that possess novel and highly functional properties. For example, the relationship between the unique properties of xanthan gum—the first microbial polysaccharide of commercial significance—and its use in major food, industrial, and oil field applications is discussed. In addition, gellan gum, the extracellular polysaccharide produced by Pseudomonas elodea , can be used in microbiological media and in gelled and structured food products. Three other industrially useful bacterial polysaccharides have been developed. S–130, the extracellular, high viscosity polysaccharide produced by a strain of Alcaligenes , has excellent suspending and heat stability properties useful in oil field drilling, workover and completion, and enhanced oil recovery fluids. S–194 has excellent suspending properties and unusual compatibility with salts, making it useful in agricultural applications, particularly flowable pesticides and liquid fertilizers. S–198 has excellent stability to shear and has potential application in the developing market of water–based lubricants.