Revista Colombiana de Biotecnología (Dec 2011)
Study of the tetanus toxin production by fermentation
Abstract
The main goal of this study was to reduce time and increase yields of the Clostridium tetani fermentation. In this work, factors that affect tetanic toxin production such as the initial concentration of glucose and glutamate, fermentation span, sterilization time and the superficial aeration were analysed. Initial glucose concentration and the sterilization time were studied simultaneously in 200 mL cultures without agitation. The initial concentration’s values were between zero and 10 g/L and the times between 10 and 60 minutes. Our results showed that cultures growing in medium containing 6g/L of glucose and sterilized by 20 minutes at 121ºC produced the highest toxin amount, with an average of 85 Lf/mL. To test the effect of the glutamate, fermentations were carried out in a stirred reactor with initial concentrations between zero and 16 g/L. Our data suggested that glutamate does not affect the yield of the toxin. However, it did increase biomass production and the rate of growth. Therefore, the fermentation span with the glutamate decreased in 41% compared with the fermentation without it. We used cultures with and without shaking to evaluate the superficial aeration. The production of the toxin increased 50% in aerated cultures without shaking while it was not affected in cultures with shaking.
