Alternative substrates for the production of the phosphate solubilizing bacteria Pseudomonas tolaasii IEXb

EMILCE VIRUEL; FAUSTINO SIÑERIZ; MARIA ESTER LUCCA

San Francisco

Congreso; Society for Industrial Microbiology 60th Annual Meeting. 2010 Annual Meeting & Exhibition; 2010

Society for Industrial Microbiology

Phosphate solubilizing bacteria (PSB) can be used for increasing the yield of major agricultural crops. Pseudomonas tolaasii IEXb (Access number FM202487) was isolated from high altitude lands of Puna (North West Argentine) and was selected as an efficient PSB with P-solubilizing activity and siderophores presence. The strain showed positive effect on root and shoot development in maize. Alternative low cost substrates (industrial and agricultural wastes) were evaluated for biomass production in batch fermentor (Microferm) under controlled conditions (pH 7, 60% oxygen saturation, 200 rpm, 37ºC). Vinasse, cheese whey, soybean meal and soy milk were evaluated. Culture media were optimized and no yeast extract was used in their formulations. Maximal biomass concentration achieved in all media tested was in the order of 1010 CFU ml-1. The biomass was concentrated by centrifugation, washed twice with buffer phosphate and spray dried and lyophilized with the addition of 1% sodium glutamate to improve biomass viability. With both conservation protocols, 1010 CFU g-1 were obtained. The results allowed to consider scaling up of the process with low cost production media for biofertilizer application for sustainable commercial crop production