ABSTRACT
Polysaccharide of N. meningitidis serogroup C constitutes the antigen for the vaccine against meningitis. The goal of this work was to compare three cultivation media for production of this polysaccharide: Frantz, modified Frantz medium (with replacement of glucose by glycerol), and Catlin 6 (a synthetic medium with glucose). The comparative criteria were based on the final polysaccharide concentrations and the yield coefficient cell/polysaccharide (Y P/X). The kinetic parameters: pH, substrate consumption and cell growth were also determined. For this purpose, 9 cultivation runs were carried out in a 80 L New Brunswick bioreactor, under the following conditions: 42 L of culture medium, temperature 35°C, air flow 5 L/min, agitation frequency 120 rpm and vessel pressure 6 psi, without dissolved oxygen or pH controls. The cultivation runs were divided in three groups, with 3 repetitions each. The cultivation using the Frantz medium presented the best results: average of final polysaccharide concentration = 0.134 g/L and Y P/X=0.121, followed by Catlin 6 medium, with results of 0.095 g/L and 0.067 respectively. Considering the principal advantages in the use of the synthetic medium, i.e. facilitation of a cultivation and purification steps of the polysaccharide production process, there is a possibility that in the near future, Catlin 6 will replace the traditional Frantz medium.
Subject(s)
In Vitro Techniques , Neisseria meningitidis, Serogroup C/genetics , Neisseria meningitidis, Serogroup C/isolation & purification , Neisseria meningitidis, Serogroup C/pathogenicity , Polysaccharides, Bacterial/analysis , Polysaccharides, Bacterial/isolation & purification , Meningococcal Vaccines/isolation & purification , Culture MediaABSTRACT
Polysaccharide of N. meningitidis serogroup C constitutes the antigen for the production of the specific vaccine against this serogroup. The production kinetics of polysaccharide (serogroup C) was studies in five cultivations carried out in an 80 L fermenter (total capacity), under the following process conditions: Frantz medium; temperature 35§C; air flow 5 L.min-1 (o.125 vvm); agitation frequency 120 rpm and vessel pressure 6 psi. Global yeld factors and ield coefficients were calculated. It was observed two distinguished polysaccharide production phases: growth associated and a growth non-associated. The cell productivity was about 0.11 (g drymass. L -1.h-1) and polysaccharide productivity near 7.0 (mg polysac. L-1. h-1)(AB)