Economic Evaluation of Streptococcus Pneumoniae Culture Media

Abstract

Streptococcus pneumoniae, a major bacterial pathogen worldwide, requires a complex medium for culture, which complicates harvesting of antigens for vaccine production. Here we present an economic evaluation of factors affecting the production cost of a chemically defined medium for the scale up of fermentation of S. pneumoniae, compared with the most traditional fermentation media. A basic laboratory-scale experiment of 1 L and an industrial-scale production of 100 L were assumed. The economic analysis results show that at 1 L lab-scale the Chemically Defined Medium (CDM) is the most expensive (US$35/L) compared to Tryptic Soy Broth medium (TSB) and Tryptic Soy Vegitone medium (TSBv), (US$2.9/L), Todd Hewitt (US$22.8/L) and Brain Heart Broth (BHI) (US$10.8/L). However at 100 L production-scale all the media costs decrease and CDM becomes competitive with Todd Hewitt and BHI (US$8.4, 9.6, 8.2/L, respectively) and slightly more expensive than both TSB media (US$2.9/L). We conclude that although some aspects of culture growth should be studied in more detail, the production cost of the chemically defined medium for industrial scale fermentation of S. pneumoniae is economically competitive on the grounds not only of price, but also taking into account other benefits such us ease of isolation, and the possibility of fine-tuning of the individual chemical species in its formulation according to the culture requirements.