Optimization of physicochemical parameters and characterization laccase enzyme produced by a novel strain of Fomes fomentarius through solid-state fermentation

This present study presents that high yield of laccase (260 +/- 1.8 U/mL) were obtained by indigenous fungal strain of Fomes fomentarius produced after 10th day of incubation at 35 degrees C using corn stover as a substrate. Furthermore, laccase was precipitated by 50% saturation with ammonium sulfate having 1.9 purification-fold after dialysis. Purification factor increased up to 2.2-fold (1.65 U/mg specific activity) with Sephadex G-100 gel filtration chromatography. The molecular weight of laccase was 44 kDa when estimated with sodium dodecyl sulfate polyacrylamide gel electrophoresis. Laccase maximum activity (230 +/- 3 U/mL) was obtained at pH 7 and increased at 35-40 degrees C up to (258 +/- 2.8 U/mL). The kinetic studies of laccase showed low Km (1 mM) with high Vmax values (60 mM/min). Purified laccase at a concentration of 0.25-1.00 mL/mL of lignin led to 80-90% lignin degradation. Laccase produced from Fomes fomentarius shown good decolorization properties (82%). Thus, Fomes fomentarius laccases can potentially be utilized in food, textile, pulp, and paper industries and also used in waste decontamination.

Automated summary

This study demonstrates the high yield of laccase production from the indigenous fungal strain Fomes fomentarius using corn stover as a substrate. The purified laccase showed optimal activity at pH 7 and 35-40 degrees C, and exhibited significant lignin degradation and decolorization properties.