Characterization of a Potential Isozyme Laccase from Trametes polyzona MPS1-3 and its Contribution to Palm Oil Mill Effluent Treatment

The high phenolic content of Palm Oil Mill Effluent (POME) constitutes an environmental concern. In this study, laccase producing microorganisms were isolated from POME samples collected in Cote d'Ivoire for their possible use in POME treatment. Strain showing the highest laccase activity was identified by ITS1-5.8S-ITS2 region sequencing as Trametes polyzona. A maximum laccase production (156.3 U/mL) was obtained after 10 days of incubation under shaking condition, at 37 degrees C, pH 4, with starch (1%), tryptone (0.3%) and 10 mM of guaiacol. The partially purified laccase of 31 kDa exhibited maximum activity at 50 degrees C and pH 4.5 with a Km for guaiacol and Vmax of 0.7 mM and 0.04 mM/min, respectively. Metals, SDS and EDTA did not inhibit his activity. Used as biotreatment agent, T. polyzona MPS1-3 reduced COD, total suspended solids, total solids and total phenolics by 16.03%, 70.15%, 38.9%, 50.84%, respectively, for sterilized POME and by 13.09%, 58.07%, 36.53%, 42.05% for unsterilized POME. These results showed the promising application of T. polyzona for bioremediation of phenolics compounds in wastewater and it potentially useful in several other biotechnological applications.

Automated summary

In this study, Trametes polyzona strain with high laccase activity was isolated and found to have promising application in POME treatment. Under specific culture conditions, this strain can significantly reduce COD, suspended solids, total solids, and total phenolics in POME.