Capsular polysaccharide production by Neisseria meningitidis serogroup C: Optimization of process variables using response surface methodology

The production of capsular polysaccharide by Neisseria meningitidis serogroup C in Frantz medium cultivations was studied. Influence of process variables such as temperature, pH and agitation speed on the polysaccharide production were investigated by means of a three-factor face-centered central composite design. An optimal set of those process variables values were calculated using response surface methodology, and results showed that optimal values were: temperature equal to 37 °C, pH controlled at 7.0 and agitation speed maintained at 1300 rpm, which correspond to a oxygen global mass transfer coefficient ( k L a) of 36 h −1. The capsular polysaccharide concentration achieved under these conditions was equal to 155 ± 4 mg/L.