Optimización de la producción de xilanasa bacteriana a partir de Bacillus sp. K1 utilizando residuos lignocelulósicos en el Departamento de Biología de la Universidad de Lakehead, Canadá.

Abstract

The objective of the present work of titration was to verify and optimize the xylanase production by the bacteria Bacillus sp. K1 in the Department of Biology at Lakehead University, Canada. The variables investigated for optimization were physical such as pH, temperature and inoculum volume; and composition of the fermentation medium such as carbon source, organic and inorganic nitrogen source and percentage ratio between these components. Additionally, the effect of metal ions (sodium, potassium, magnesium, calcium, ferrous, nickelous, cupric, cobaltous and manganous) and surfactants (polysorbate-20, dodecyl sodium sulfate and Triton X-100) in the enzymatic activity of the xylanase produced was determined. The highest production of xylanase was after 36h fermentation and the optimal physical conditions associated with the production of xylanase were pH 6, temperature 35 ºC and inoculum volume 1%. The optimum composition of the fermentation media consists of: wheat bran 4%, glucose 0.5%, NH4NO3 0.5%, K2HPO4 0.1%, KCl 0.1%, MgSO4 0.05%, peptone 0.5%, SDS 0.1%. The enzyme activity generated is 264.96±7.89 IU/L, with a 248,79% from the initial experiment. The most important inhibitors were cupric and manganous ions with 32% and 49,16% inhibition compared to the control experiment. The physical conditions of fermentation and the presence of cellulase provide a future application in the second-generation bioethanol industry.