The instant invention provides a novel feed solution and optimal feeding strategy for obtaining higher yields of bacterial polysaccharides, more particularly N. meningitidis W polysaccharide at harvest stage. A feed solution comprising of glucose, amino acids and vitamins along with an optimal fermentation medium produces Group W polysaccharide having harvest yield of greater than 1000mg/l which is approximately 2 times the level observed with previously reported feed solutions and fermentation methods. Also, the desired harvest is successfully used to obtain the polysaccharide with desired O-acetylation level, minimum protein and nucleic acid content.
