Idiosyncratic investigation of Trametes versicolor yellow laccase using organic fruit exocarp in solid-state fermentation

The involvement of enzymes to utilize lignocellulosic biomass into biorefinery is often a challenging task. The fruit exocarp-jackfruit, pineapple, and kaffir were utilized for the production of yellow laccase by Trametes versicolor at solid-state fermentation. Laccase, a protagonist enzyme, has a major vital application in biotechnology field. The laccase productivity from jackfruit exocarp was increased from 4.71 to 9.58 U/mL at 25 degrees C respectively on the twenty-second day, whereas by exocarps of pineapple and kaffir was reduced to 5.72 and 4.91U/mL. The highest enzyme production was performed at an equal molar ratio of inorganic substrates with pH 4, 70% of moisture content at 25 degrees C. Furthermore, the yellow laccase was purified and obtained 2.23-fold higher than crude enzyme with specific activity as 4.43U/mg. The molecular weight of the purified laccase enzyme was 44 kDa with protein concentration as 83 mu g/mL; copper content as 219.1 mu g/L, and carbohydrate content with 8% were procured. The laccase activity towards guaiacol substrate was examined by Lineweaver-Burk plot. The kinetic studies of laccase shows K-m value of 1.8 mM and V-max 4.8 mu mol/ml/min. The rate constant k(cat) was 0.0267 mol L/s and the substrate specificity of the enzyme k(cat)/K-m was 152.44/M/s. The production and the characteristic study of T. versicolor laccase were confirmed by UV spectra and FTIR, which showed stronger intensity at beta-sheet than at alpha-helix. The surface of the fruit exocarps and the laccase enzyme were examined under SEM. This one-step approach of metabolic process the finite resources optimize the productivity, diminish the greenhouse gas emissions, and hence a revolutionary change from the linear economy to circular economy.

Automated summary

The involvement of enzymes in utilizing lignocellulosic biomass for biorefinery is a challenging task. This study focused on producing yellow laccase using the fruit exocarp of jackfruit, pineapple, and kaffir through solid-state fermentation. The highest laccase productivity was observed from jackfruit exocarp, with specific conditions for optimal enzyme production. After purification, the yellow laccase had increased activity and a molecular weight of 44 kDa. The findings demonstrate the potential of using these fruit exocarps for laccase production.