Immobilization of partially purified laccase on polyhydroxyalkanoate (PHA) microbeads and its application in biodegradation of catechol

Abstract BACKGROUND One significant component of new, rapid economic development is the creation of biodegradable polymers. One of these biopolymers is polyhydroxyalkanoate (PHA). This biodegradable, thermoplastic and water‐insoluble storage polymer can be generated from sustainable carbon sources. PHA may be effectively used for treating wastewaters by immobilizing enzymes. For eliminating micropollutants along with many phenolic compounds, laccase is considered as a potential enzyme. Hence, it has been known to be highly effective for water purification procedures. However, adequate immobilization is required for laccase to perform efficient catalysis. The immobilization procedure increases laccase stability with respect to reusability, temperature, pH and storage, making it superior to free laccase. RESULT In the present study, laccase was partially purified from Beauveria pseudobassiana PHF4 by gel filtration chromatography and further immobilized on PHA microbeads. The crude extract displayed specific activity of 19.08 U mg −1 and PHA microbeads demonstrated immobilization efficiency of 77.44%. Characterization of PHA microbeads by scanning electron microscopy showed an increase in their size from 3–5 μm to 5–6 μm after the immobilization. Furthermore, catechol biodegradation by immobilized laccase was analyzed using UV–visible spectrophotometry (84.25% in 10 h), which was also confirmed by high‐performance liquid chromatography (83.65% in 24 h). CONCLUSION Iimmobilizing laccase on PHA microbeads can help to address the pollution and environmental damage that catechol and similar chemicals cause also in an ecofriendly manner. © 2024 Society of Chemical Industry (SCI).