Optimization of fermentation parameters for the production of antimicrobial compounds by Fusarium falciforme MNP1 isolated from rhizosphere soil of Epipremnum aureum

In the present study, Fusarium falciforme MNP1 (Gen Bank Accession no. PX106850) was isolated from the rhizosphere soil of Epipremnum aureum (Money Plant), which showed the remarkable antimicrobial activity against the test microorganisms ( Escherichia coli MTCC- 40, Pseudomonas aeruginosa MTCC-647, Bacillus subtilis MTCC- 2274, Staphylococcus aureus MTCC-6908, Aspergillus niger MTCC- 281 and Candida albicans MTCC- 183). One Factor at a time (OFAT) and Response Surface Methodology (RSM) were used for the optimization of the fermentation parameters for antimicrobial production. In the OFAT design, fermentation parameters such as pH (4–8), temperature (15–35℃), incubation period (7–15 days), inoculum size (0.25–1.25 ml) and fermentation vessel size (250–2000 ml) were considered. Response surface methodology (RSM) based central composite design (CCD) model was performed to evaluate the interactions and the quadratic effect on the antimicrobial metabolites production which inhibit the test microorganisms (responses) in terms of the diameter of zone of growth inhibition (mm). Three variables namely incubation time (days), pH, and temperature (℃) were employed with RSM and investigated with the help of quadratic equations to increase the production of bioactive metabolites. The experimental data to maximize the production of bioactive metabolite was significantly fit by using the second polynomial model. Regression analysis revealed that the model was found significant on the basis R ² values for all the six responses and values of adjusted R ² demonstrated the perfect agreement with predicted and experimental values. Methodology (RSM) enhanced the production of bioactive compounds by Fusarium falciforme with optimized conditions pH 6, 25℃ temperature and 9 days of incubation period. By using the central composite design, the accurate values of fermentation parameters for the production of antimicrobial compound can be concluded and further characterization of the antimicrobial metabolites is needed for future prospect.