U S. BAGDE, RAM PRASAD AND AJIT VARMA
Abstract
In order to get bulk culture of P. indica for formulation in commercially and economically cost effective bio fertilizer, it was cultivated in a 5 litre capacity fermenter (New Brunswick, USA). The medium used was Aspergillus medium. P. indica was grown in Aspergillus medium which was the best medium for optimum growth as was evidenced by flask culture experiment with the organism. Various parameters of the fermentation were measured, maintained and recorded over the period of 20 days. It was observed that the pH of the medium in the range of 6.5 to 6.7 was more favorable for optimum growth of the organism. Temperature range of 25 to 35 was favorable for the growth of P. indica and not affected adversely. However, the temperature of 30deg.C was optimum and more favorable for optimum growth of P. indica. Oxygen requirement of the culture was fulfilled by forcing filtered air at 1.0 LPM concentration via sparger and it gave satisfactory results. Air bubbles were released in fine air bubble form and impeller distributed it efficiently throughout the broth medium. Baffles helped in process of agitation and avoided vortex formation. Growth proceeded in most obvious and satisfactory manner under the optimized conditions. Though there was short lag period, growth of the organism commenced soon as was evidenced by Optical Density readings taken subsequently after inoculation. Sporulation was observed in normal course due to optimization of gr