Title
Production of cellulases from Pseudomonas stutzeri using mango peels as a substrate in submerged fermentation
Authors
SADIA LIAQAT, IRFAN AHMAD, HAFIZ ABDULLAH SHAKIR, MUHAMMAD KHAN, MARCELO FRANCO and MUHAMMAD IRFAN

Received April 8, 2024
Published Volume 58 Issue 9-10 September-December
Keywords Pseudomonas stutzeri, cellulases, submerged fermentation, lignocellulose biomass

Abstract
Enzymes are biocatalysts produced by microorganisms using plant materials as a substrate. Green chemistry uses plant materials to produce enzymes, while fermentation technology produces enzymes on larger scales. These enzymes can be used in food, textile, paper industry and biofuel production. Cellulase is an industrial enzyme that breaks the β-1,4 glycosidic bond of polysaccharides in plant cells and can be produced by various microorganisms. Mango waste can be used to produce bioactive compounds, such as cellulase enzymes, from microorganisms in submerged fermentation (SmF). The production of endoglucanase and exoglucanase from Pseudomonas stutzeri using mango peels as a substrate in SmF was optimized using one factor at a time and response surface methodology. The optimum conditions for CMCase were 4.5% substrate concentration, 96 hours incubation time, and 2.5% inoculum size, while optimum conditions for FPase were 4.5% substrate concentration, 48 hours incubation time and 0.5% inoculum size. PBD was employed for the screening of various nutritional components, such as K2HPO4, KH2PO4, (NH4)2SO4, NaCl, MgSO4, FeSO4 and CaCl2, and it was found that significant nutritional parameters were FeSO4, MgSO4 and (NH4)2SO4. Through the Central Composite Design, maximum production of endoglucanase, i.e. 120.112 IU/mL/min, was found at 0.1% (NH4)2SO4, 0.1% MgSO4 and 0.45% FeSO4, while maximum exoglucanase production, i.e. 161.38 IU/mL/min, was recorded at 0.1% (NH4)2SO4, 0.5% MgSO4 and 0.05% FeSO4. The optimum temperature and pH for maximum CMCase and FPase activity were 50 °C and 7.0, respectively. Endoglucanases and exoglucanases were stable up to 50 °C and pH 7. Metal ions such as Mn2+ and Cu2+ activated the activity of CMCase and FPase, respectively, while Zn2+ and Na+ inhibited CMCase and FPase activity, respectively.