Production and purification of Vi polysaccharide from Salmonella enterica typhimurium (MTCC98)Author(s): Shipra Kalra, Kanav Midha, Bhanu Pratap Singh Shekhawat
The main objective of the research is enhanced production of Vi Antigen by the modification of fermentation media. The optimized concentration of Tryptophan is 0.5 g/100ml, Glucose concentration is 1g/100ml and the optimized Temperature is 350C. With decrease in concentration of Glucose, production of Vi antigen is enhanced. The quantification has been done by Single Radial Immuno Diffusion Assay. The conc. of Vi antigen is found to be 12µg in 0.6 mm diameter and 27 µg in 0.9 mm diameter ring. For the determination of purity of Vi polysaccharide OD at 215 nmis takenand the obtained values for crude broth, partially purified Vi polysaccharide, purified Vi polysaccharide are 0.853, 2.190 and 3.104 respectively. Thus, the highest optical density in purified Vi polysaccharide showed high Vi concentration. In purified Vi polysaccharide,74% recovery has been obtained by Gel filtrationchomatography. Thus,Vi polysaccharide yields good recovery by Sephadex G200 at lowcost.