title: Use of spent mushroom substrate for production of Bacillus thuringiensis by solid-state fermentation.
abstract: The aim of this study was to explore a cost-effective method for the mass production of Bacillus thuringiensis (Bt) by solid-state fermentation. As a locally available agroindustrial byproduct, spent mushroom substrate (SMS) was used as raw material for Bt cultivation, and four combinations of SMS-based media were designed. Fermentation conditions were optimized on the best medium and the optimal conditions were determined as follows: temperature 32 degrees C, initial pH value 6, moisture content 50%, the ratio of sieved material to initial material 1:3, and inoculum volume 0.5 ml. Large scale production of B. thuringiensis subsp. israelensis (Bti) LLP29 was conducted on the optimal medium at optimal conditions. High toxicity (1,487 international toxic units/milligram) and long larvicidal persistence of the product were observed in the study, which illustrated that SMS-based solid-state fermentation medium was efficient and economical for large scale industrial production of Bt-based biopesticides. The cost of production of 1 kg of Bt was approximately US$0.075.
authors.forename: Songqing
authors.initials: S
authors.lastname: Wu
authors.forename: Yanjiao
authors.initials: Y
authors.lastname: Lan
authors.forename: Dongmei
authors.initials: D
authors.lastname: Huang
authors.forename: Yan
authors.initials: Y
authors.lastname: Peng
authors.forename: Zhipeng
authors.initials: Z
authors.lastname: Huang
authors.forename: Lei
authors.initials: L
authors.lastname: Xu
authors.forename: Ivan
authors.initials: I
authors.lastname: Gelbic
authors.forename: Rebeca
authors.initials: R
authors.lastname: Carballar-Lejarazu
authors.forename: Xiong
authors.initials: X
authors.lastname: Guan
authors.forename: Lingling
authors.initials: L
authors.lastname: Zhang
authors.forename: Shuangquan
authors.initials: S
authors.lastname: Zou
mesh_terms: D000363:Agaricales; D000818:Animals; D001413:Bacillus thuringiensis / Q000254:growth & development*; D003465:Culex; D003470:Culture Media; D005285:Fermentation; D018675:Toxicity Tests
chemical_list: D003470:Culture Media