Downstream processing of mosquitocidal toxins from solid state fermentation of Lysinibacillus sphaericus and Bacillus thuringiensis israelensis

Abstract

Aims:The aim of this study was downstream processing of moquitocidal toxins produced by Lysinibacillus sphaericus (L. sphaericus) and Bacillus thuringiensis israelensis (Bti) under solid state fermentation. Methodology and results: Two mosquitocidal strains (L. sphaericus and Bti) were grown separately in trays under solid state fermentation for toxin production. The best conditions for extraction of crude toxins from fermented solids of both cultures were tap water at 5-50 °C, for 10 min under static conditions. Also, concentrated mosquitocidal toxins were efficiently extracted from fermented solids by 4 constitutive additions of 500 mL tap water to 1 kg of fermented culture at room temperature (25 °C) for 5 min each under static conditions. Both extracted toxins were formulated with talcum powder and they were stable for 8 months at room temperature. Conclusion, significance and impact of study: It is very important to study the operating conditions for mosquitocidal toxins extraction from solid state fermentation (SSF) and its formulation in cost effective manner.

Solid-State Fermentation from Organic Wastes: A New Generation of Bioproducts

“…Searching in the Scopus ® database using the key words "solid state fermentation" AND "downstream" but not including enzymes, resulted in only 37 articles from more than the last 20 years. Even then, most of these articles either just mention downstream but do not deal with it [20] or they focus on the optimization of the extraction method on a small scale [91,92]. For these reasons, this review will be focused on the most common recovery strategies independently of the scale.…”