Abstract
The feasibility of using orange peel residues as a substrate for induced sporulation of Trichoderma asperellum was evaluated. The Box-Behnken matrix (BBM) design was used to screen the effects of several parameters, including the effect of pH, inoculum, and moisture under solid-state fermentation culture conditions. The study was performed in two experimental steps (screening and optimization). Moisture content and pH were determined to be the most influential parameters on spore production during the screening stage. A Box-Behnken design was used to optimize and to define the interaction of the selected parameters. The moisture content was determined as the most significant parameter affecting spore production. An inoculum of 1 x 10(6) spores g(-1) , pH 6.07, and moisture content of 69.0% was the combination of conditions observed to achieve the maximum production of 2.04 x 10(9) spores g(-1). The experimental value of 2.16 x 10(9) spores g(-1) (from the experimental model) showed a good fit to the regressed model, with a standard error of 5%. Based on this work, a high yield of spores was obtained at 144 h of cultivation time, indicating that it is a feasible approach to use orange peel as a substrate for biomass and spore production.