Xylanopectinolytic accessory enzymes of Bacillus spp. from ruminant dung for enzymatic agrowaste biomass saccharification

The final sugar yield in the first step of biofuel production from lignocellulosic biomass is determined by the extent of its saccharification by mixture of polysaccharide deconstructing enzymes. A combined action of enzymes comprising "Core enzymes” like cellulases and "Accessory enzymes"  like  xylanases, pectinases etc. accomplish this. Our aim was to prepare an efficient enzyme cocktail, by optimizing the influence of various parameters on it, so as to achieve an  improvement in the saccharification process. Ruminant animals consume cellulose, xylan and pectin containing plant based food material, soften it in their stomach, where bacteria produce diverse polysaccharide deconstructing enzymes facilitating the digestion of food. As a result large number of such bacteria are excreted in their dung. From this perspective 153 bacterial cultures were isolated from the dung samples of cow, camel and buffalo and were screened for the production of cellulase, xylanase and pectinase.  Out of the total 153 isolates ~60% were found to produce all the three enzymes.Upon further screening and identification three potential isolates Bacillus safensis M35 and Bacillus altitudinis R31 and J208 were selected for studies. Crude xylanases and pectinases demonstrated their potential as accessory enzymes when supplemented to commercial core Cellulase Primafast® 200 as it gave increase in saccharification of Barley husk, Sugarcane bagasse and Wheat husk. The enzymes were characterized. The results obtained in the studies would be discussed at length.