UTILIZATION OF UNHYDROLYZED CHEESE WHEY FOR THE PRODUCTION OF EXTRACELLULAR POLYSACCHARIDE BY XANTHOMONAS-CUCURBITAE PCSIR B-52

A strain of Xanthomonas cucurbitae PCSIR B-52 produced extracellular polysaccharide using partially deproteinized cheese whey without hydrolysis. A synthetic lactose-salt medium was also utilized to determine the optiomum level of lactose desirable for successfull fermentation. The amount of extracellular polysaccharide was maximised at 7.8 gl-1 in the presence of 40 gl-1 lactose. The bacterium efficiently consumed cheese whey, particularly in the presence of corn steep liquor and penicillin waste mycelium in shaken flasks. The polysaccharide, bacterial cell mass and viscosity gradients were improved as a result of efficient oxygen transfer in a mechanically agitated fermentor. A depletion in dissolved oxygen tension resulted during the exponential growth phase. The fermentation pattern of extracellular polysaccharide was also studied by repeated batch process. © 1990.