Isolation and Screening of Lignin Degrading Bacteria from Different Natural and Organic Sources

Increased consumption and high dependence on non – renewable sources has substantially contributed to global warming and environmental pollution. Hence, alternative strategies for energy production have to be looked and one of the alternative is producing 2nd generation Bio-ethanol from lingo-cellulosic material. Maize cob is one of the Lignocellulosic material is one the substrate, which can be used for Bio-ethanol production (It is rind after removing the seeds). The present study is focused on to look for novel strains of lignin degrading bacteria from various organic sources. The different sample sources used for the isolation of lignin degrading bacteria were from cow dung, compost, forest soil, garden soil in agriculture college, Hassan. Enrichment of sample source was also done by mixing the paper, corncob, compost, cowdung and soil in different proportions and kept for 15 days at room temperature. Enriched samples were also used as a source for isolation of lignin degraders. Totally 64 colonies were isolated by screening in 7 different sample sources, from those 64 isolates, only 25 isolates confirmed as lignin degraders through conformational test. Decolourization zone produced by 25 isolates was measured. Eight isolates that produced large decolurization zone (0.5 to 1 cm) were selected and further screened for their tolerance to lignin by culturing them on 2% lignin. The results pertaining to growth on 2% Alkaline lignin is, isolate CC- 10 was grown within 24hr followed by CM-3, PC- 2,PC- 3, PC-5 and CC- 8 they were grown within 48hr. The growth of FS- 3 and CC-10 were seen within 72hr. Based on the results obtained the slow grower FS-3 and CC-10 was discarded. Six potential isolates which are showing large clear zone (decolourized) of methylene blue dye and also rapid growth on MSM with 2% alkaline lignin were selected. Based on this to reconfirm the isolates as a lignin degrading bacteria Protein profiling of the six isolates has been done by using SDS – PAGE technique.