Isolation, characterization and production of bacterial laccase from Bacillus sp.

Abstract

Two species of Bacillus exhibiting laccase activity were screened from earthworm cast and soil samples. The M162 medium with 5 mM guaiacol was used for isolating bacterial strains capable of oxidizing guaiacol. One species was identified as Bacillus pumilus and the other as Bacillus licheniformis based on the result of biochemical tests and 16S rDNA analysis. B. pumilus and B. licheniformis could grow at temperature ranging from 30–55 °C and showed optimum growth at temperature 37°C and pH 8.0 and 5.0. Laccase activity was maximum at 37 °C and pH 7.0. They were found positive for different hydrolytic enzymes. The dyes toluidine blue O and rose bengal were degraded within 24 h.