Pomegranate peel utilization by an indigenous fungal strain of Trichoderma reesei NCIM 1186: Optimization and Kinetics studies on production of cellulase

Pomegranate peels, which are normally considered waste, are used for the synthesis of cellulase in this study. Through submerged state fermentation, Trichoderma reesei filamentous fungus was employed to manufacture cellulase from pomegranate peels. Response Surface Methodology was used to screen the nutritional medium and improve the media composition for cellulase production using statistical experimental methods (RSM). Nine nutrients were screened using the Plackett–Burman Design (PBD) technique and the most impacting nutrient mediums were chosen. Central Composite design (CCD) identified four nutrients as being more critical for cellulase production, and their compositions were optimized as well. The best medium compositions for submerged fermentation of cellulase using pomegranate peel were Avicel—24.812 g/L, KH₂PO₄—4.626 g/L, soybean cake flour—20.7 g/L, and MnSO₄.H₂O—1.036 g/L. Cellulase production was determined to be 9.3 IU/mL under optimum medium conditions. Furthermore, Box–Behnken Design improved process parameters such as pH (5.5), temperature (36 °C), initial substrate concentration (3.2%), inoculum concentration (7%), and fermentation length (5 days). Finally, under the optimum medium and process conditions, the maximal cellulase production was 12.3 IU/mL. The Monod model (R²:0.9316), Luedeking–Piret model-substrate consumption (R²:0.9217), Michaelis–Menten kinetics (R²:0.94), Lineweaver–Burk plot (R²:0.9264), Hanes–Woolf plot (R²:0.0642), and Eadie–Hofstee plot (R²:0.0642) were used to model the cellulase production process. Furthermore, pomegranate peels, a cheap waste raw material, would be the best carbon source for a high production of cellulase enzyme.