STRATEGIC ISOLATION AND SCREENING OF LACCASE-PRODUCING MICROBES IN SOLID-STATE AND SUBMERGED FERMENTATION FOR SUSTAINABLE DYE DECOLORIZATION

Laccase, a polyphenol oxidase enzyme, is prominent for its catalytic potential in oxidizing various aromatic compounds, including the complete decomposition of wood elements. This enzyme is naturally prevalent among plants, insects, microbes, and fungi and is essential for several biotechnological applications due to its high redox potential, notably in dye degradation, wastewater treatment, and soil detoxification. Our study focused on isolating, screening, and increasing laccase production from specifically chosen bacterial and fungal sources. We identified nine bacterial and three fungal strains from various polluted sites and natural environments. These strains were cultivated, with laccase activity measured through ABTS assays for bacteria and GUAIACOL assays for fungi, leading to important findings on enzyme activities. The laccase was further refined using a nutrient medium with added tannic acid and partially purified by ammonium sulphate precipitation. This purified form displayed the capability to decolorize Azo dyes efficiently. Lastly, we evaluated the efficacy of laccase in breaking down dyes and their future use in the decolorization of parchment paper, indicating a promising field of application for this microbial synthesized laccase enzyme.