Production of Bacillus thuringiensis Berliner var. kurstaki Grown in Alternative Media

Abstract

Agro-industrial residues and by-products available in southeastern Brazil were used as ingredients for low-cost culture media for liquid fermentation of Bacillus thuringiensis var. kurstaki. Highest spore yield was obtained with a medium containing cheese whey, soya bean milk and mofasses (WSM). Crystals and spores were produced in ali media and potency o f the final product was highest for nutrient broth + yeast extract medium (N B Y). There was no correlation between the number of spores in the fermented media and the potency of the preparations. Considering ali three factors, the potencies, costs and yields of the final products, lowest relative cost was obtained with BM M medi um (Bombyx mo ri pupae + mo/asses). NBY and WSM had intermediate relative cost approximately nine times higher than BMM. The cost analysis suggests that BMM medium should be preferred for local production o f B. thuringiensis var. kurstaki in comparison to other media tested. The results ais o demonstrate the importance o f considering yields, cost and potency o f the B. thuringiensis preparations in selecting the production medium.

Optimization of Bioinsecticides Overproduction by Bacillus thuringiensis subsp. kurstaki Using Linear Regression

“…e results indicate that it exhibits a supressive e ect at high levels, on delta-endotoxins production but improves protease activity and spores counts. In fact, Alves et al (1997) stated that the culture medium should be brought to neutral pH at harvest because high pH is optimal for Bacillus thuringiensis proteases and potentially damaging to the crystals. Furthermore, Ejiofor and Okafor (1989) concluded that low pH can restrain growth, sporulation and crystal formation of B. thuringiensis.…”

Desenvolvimento de um meio de cultura de baixo custo para Bacillus thuringiensis subsp. israelensis

“…This has called for a growing need to develop B. thuringiensis subsp. israelensis based products to be used in local insect control programs, as previously suggested (ALVES et al, 1997;COUCH;ROSS, 2004;MORRIS;KANAGARATNAM;CONVERSE, 1997;POOPATHI;KUMAR, 2003;PRABAKARAN;BALARAMAN, 2006;VORA;SHETHNA, 1999).…”

Regulation of major cultural components for designing a cost effective medium to increase -endotoxin synthesis by Bacillus thuringiensis

“…kurstaki. Highest spore yield was obtained with a medium containing cheese whey, soya bean milk and molasses (Alves et al, 1997). Other wastes, such as, sludge and broiler poultry litters were also utilized for biopesticides production (Adams et al, 2002;Vidyarthi et al, 2002).…”