Utilization of waste glycerol for the production of biocontrol agents nigericin and niphimycin by : bioprocess development.

Search for more environment-friendly methods for controlling plant diseases that would contribute to the goal of sustainability in agriculture is in focus. In the present study, the potential of isolated from soil sample in the production of biocontrol agents, nigericin and niphimycin, effective against storage apple pathogen was examined. Also, modelling and optimization of medium composition for biocontrol agent biosynthesis was performed. The results showed that the optimum amount of CHO, (NH)SO and KHPO in the medium for biosynthesis is 20, 0.25 and 1.46 g/L, respectively. and validation of the obtained results performed in the 3 L laboratory-scale bioreactor showed that on the optimized medium at an aeration rate of 0.7 vvm and an agitation speed of 200 rpm, produced nigericin and niphimycin, showed high activity. Under the same conditions, cultivation of was performed in a 7 L laboratory bioreactor in a medium with waste glycerol instead of pure glycerol. Results showed that the methanol extract of cultivation liquid, containing nigericin and niphimycin, was high effective against two isolates. This was confirmed by obtaining large inhibition zone diameters on KA10 (47 mm) and T1Jg (44.33 mm) isolates. After successful analysis, testing was performed. It was found that necrosis diameters that were measured on artificially inoculated apple fruits with compared to necrosis diameter measured on untreated, control fruits, were 4.47 and 3.56 times smaller.