Evaluation of cellulase and xylanase production by two actinobacteria species belonging to the Micrococcus genus isolated from decaying lignocellulosic biomass

Bacteria were isolated from sawdust and screened for cellulase and xylanase production on carboxyl methyl cellulose (CMC) and birchwood xylan agar. The bacteria showing halo forms around the colony were selected for further analyses and those isolates with the highest cumulative halozone size (isolate PLY1 and MLY10) were chosen for detailed studies. Evaluation of cellulase and xylanase production by saw dust actinobacterial species whose 16S rDNA nucleotide sequences were deposited in GenBank as Micrococcus luteus strain SAMRC-UFH3 with accession number KU171371 and Micrococcus yunnanensis strain SAMRC-UFH4 with accession number KU171372. Optimum culture conditions for the production of cellulase for respective axenic culture include incubation period (96 h), incubation temperature (25oC), agitation speed (50 rpm), and pH 5. For xylanase production, the optimum culture conditions in the presence of 1percent (w/v) birchwood xylan include incubation period (84 h), incubation temperature (25oC), agitation speed (200 rpm), and pH 10. For Micrococcus yunnanensis strain SAMRC-UFH4 cellulase production was optimal under such conditions as, incubation temperature (30oC), agitation speed (0 rpm), and pH 5, while xylanase production was optimal at, incubation temperature (30oC), agitation speed (150 rpm), and pH 10. The high cellulase and xylanase activity obtained from these isolates suggest suitability of the organisms as important candidates for commercial application. ; Thesis (MSc) -- Faculty of Science and Agriculture, 2016