Abstract:
Biological control is considered a means of controlling the numerical density of
pests, through the use of parasites, predators and pathogens, in addition to
entomopathogens, which are microorganisms present in agricultural environments,
which include bacteria, fungi and viruses.
Bacillus subtilis, an aerobic bacterium capable of producing effective substances to
combat the enemies of agricultural crops, by secreting a toxin called fengycin. The
production of biopesticide, on a laboratory scale, in a 2 liter bioreactor, containing a
culture medium based on olive pomace (a by-product of the olive industry) requires
an optimization of the oxygen transfer in this place. The optimal kLa value was
estimated at 0.0053 s-1 for values: Qa = 2 vvm, N = 300 rpm, S = 0.1%. The aeration
rate and the agitation speed positively influence the oxygen transfer, while the
substrate concentration has a negative and insignificant effect on the O2 transfer
phenomenon. Olive pomace powder supplemented with peptone is sufficient for the
multiplication of Bacillus sp. in a 2 liter bioreactor, and allows the production of
fengycin, to fight against Fusarium F.O
