High biodegradation levels of 4,5,6-trichloroguaiacol by Bacillus sp. isolated from cellulose pulp mill effluent

Abstract

An aerobic Gram positive spore-forming bacterium was isolated from cellulose pulp mill effluent. This microorganism, identified as Bacillus sp. and named IS13, was able to rapidly degrade the organic chlorinated compound 4,5,6-trichloroguaiacol (4,5,6-TCG) from a culture containing 50 mg/l, which corresponds to about 3x104 times the concentration found in the original effluent. The biodegradation of this compound, usually found in cellulose pulp mill effluents, was evaluated by spectrophotometry and gas chromatography analysis. During 4,5,6-TCG decreasing, the lack of by-products had shown by such analysis lead to verify the possibility of either adsorption or absorption of 4,5,6-TCG by the cells, instead of real biodegradation. There were no traces of 4,5,6-TCG after lysozyme and SDS cell disruption. Vigorous extraction was applied before spectrophotometry analysis and there was no release of residual 4,5,6-TCG. Plasmid isolation was attempted by using different protocols. The best results were reached by CTAB method, but no plasmid DNA was found in Bacillus sp. IS13. The results suggest that genes located at the bacterial chromosome might mediate the high decrease of 4,5,6-TCG. The importance of this work is that, in being a natural ocurring microorganism, Bacillus sp. IS13, can be used as inoculum in plant effluents to best organochlorinated compounds biodegradation.

Unraveling aerobic cultivable cellulolytic microorganisms within the gastrointestinal tract of sheep (Ovis aries) and their evaluation for cellulose biodegradation

“…4-5). It has been widely reported that genus Bacillus contained numerous aerobic or facultative aerobic cellulose-degrading bacteria, which can be isolated from soil or other waste materials with high cellulose content (Tondo et al 1998;Su et al 2006). Also, B. subtilis can express multi-cellulase containing minicellulosomes on its surface to enhance the degradation of lignocellulosic biomass (Liu et al 2012;You et al 2012).…”