title: Optimization of Inocula Conditions for Enhanced Biosurfactant Production by Bacillus subtilis SPB1, in Submerged Culture, Using Box-Behnken Design.
abstract: The inoculum age and density can influence considerably the production yield and cost of the fermentation process. Some literature studies report the use of two-stage inocula to enhance metabolite production. In the present study, optimization studies were done in order to define the best inocula conditions supporting a maximum biosurfactant production by Bacillus subtilis SPB1. Hence, by adjusting the levels of the two-stage inocula strategy, lipopeptide production was effectively enhanced to almost 3.4 g/l as estimated gravimetrically. The new defined parameters were as follows; a first inoculum age of 23 h followed by a second inoculum age and size of 4 h and 0.01, respectively. Thereby, we note an improved production as compared to the production yield described under non-optimized inocula conditions reported in our previous work.
authors.affiliation: Unité «Enzymes et Bioconversion», National School of Engineers of Sfax, ENIS, BP W 3038, Sfax, Tunisia. inesmnif2011@gmail.com.|Higher Institute of Biotechnology of Sfax, Sfax, Tunisia. inesmnif2011@gmail.com.
authors.forename: Ines
authors.initials: I
authors.lastname: Mnif
authors.affiliation: Unité «Enzymes et Bioconversion», National School of Engineers of Sfax, ENIS, BP W 3038, Sfax, Tunisia.
authors.forename: Semia
authors.initials: S
authors.lastname: Ellouze-Chaabouni
authors.affiliation: Unité «Enzymes et Bioconversion», National School of Engineers of Sfax, ENIS, BP W 3038, Sfax, Tunisia.|Higher Institute of Biotechnology of Sfax, Sfax, Tunisia.
authors.forename: Dhouha
authors.initials: D
authors.lastname: Ghribi
keywords: Biosurfactant production; Optimization; Response surface methodology; Two-stage inocula