Development of a cleaner technology for pulp and paper industry isolation and application of a bacterium producing cocktail of lignolytic and hemicellulolytic enzymes

Abstract

The study was to develop a cocktail of hemicellulolytic and lignolytic enzymes for their application in pulp and paper industry to make the whole process of paper making eco friendly. An environmental isolate Bacillus tequilensis LXM55 was isolated, which produced a cocktail of lignolytic (Laccase) and hemicellulolytic (Xylanase and Mannanase) enzymes. All the enzymes were found to be active/stable at high temperature and pH which was suitable for their application in pulp and paper industry. Conditions were optimized to enhance the yield of the enzymes in submerged and solid state fermentation by using classical and statistical methods. Laccase, xylanase and mannanase of enzyme cocktail were partially purified and characterized. Apart from high temperature and pH, all the enzymes were found to be highly stable in the presence of various chemicals and agents. Hence, were suitable for their application in various industrial processes. Process was standardized for the application of cocktail of enzymes in pulp and paper industry for the biobleaching of pulp. Significant reduction in the use of chlorine and pollution load was achieved under standardized conditions. Enzyme cocktail was also found to be useful for the application in pulp biobleaching in combination with physical methods such as microwave irradiation of pulp. Therefore cocktail of enzymes produced by Bacillus tequilensis LXM55 was found to be highly suitable for developing a cleaner environmental friendly process for pulp and paper industry. newline