Effect of culture media and their ingredients on Poly ribosyl ribitol phosphate (PRP) production by Haemophilus influenzae

Background and Aim : Haemophilus influenzae type b (Hib) is a gram-negative encapsulated bacterium responsible for severe diseases, including epiglottitis, pneumonia, sepsis, and meningitis almost exclusively in children aged less than ۵ years. The widespread use of Hib conjugate vaccines in infancy has led to a dramatic decline in the incidence of invasive Hib disease in children. Capsular polysaccharide, Poly ribosyl ribitol phosphate (PRP) of Haemophilus influenzae type b (Hib), is important for the production of the conjugate vaccine, the production of PRP is directly related to the culture media and their ingredients. Capsular polysaccharide, Poly ribosyl ribitol phosphate (PRP) of Haemophilus influenzae type b (Hib), is important for the production of the conjugate vaccine and its production directly related to the culture media. The industrial production of the PRP capsular polysaccharide requires the cultivation of Hib in a modified medium, which impacts process costs and product purification. The present study aims to investigate the effect of the growth factor medium component on PRP production by Hib.Methods : The industrial production of the poly ribosyl ribitol phosphate (PRP) capsular polysaccharide requires the cultivation of Hib in a modified medium, which impacts process costs and product purification. In this study, a central composite experimental design strategy was used to access the influence of key components of culture medium (percentage of dissolved oxygen, and glucose concentration) on biomass formation and polysaccharide production in ۵-liter shake-flasks.Results : The optimized medium condition, containing dissolved oxygen (۳۰-۱۰%) and glucose concentrations(۱۰-۱۵g/l) was further validated in fed-batch bioreactor cultivations. Maximum PRP production (~ ۹۰۰μg /ml) was obtained in this production process for use in Hib vaccine production.Conclusion : In this study, we were able to get a higher rate of PRP in a simpler culture media by replacing Cas amino acid with Soy peptone which is in line with the World Health Organization goal to reduce the production costs. therefore we decided to improve culture media and produce more PRP as one of the components of the Pentavalent vaccine to reduce the production costs.

کلیدواژه ها:

Haemophilus influenzae type b ، Poly ribosyl ribitol phosphate ، vaccine ، culture medium