Ethanologenic potential of the bacterium Bacillus cereus NB-19 in media comprising of sugar mill and dairy industrial wastes
AbstractEthanologenic bacterium was cultivated in a suspension of sugarcane bagasse and processed yogurt whey under the predetermined growth optimized conditions. It was found that blending of processed
defatted yogurt whey with 2% sugarcane bagasse (MNCH-9 medium) caused significantly higher growth of the bacterium after 24 h of incubation as compared to the values obtained when the Bacillus cereus-
NB-19 was cultivated in MNCH-2 (2% bagasse in distilled water) and MNCH-10 (only processed whey). Saccharification potential of the bacterium increased significantly when the bagasse was supplemented with whey. Glucose contents of the cultured MNCH-9 turned out significantly higher as compared to the corresponding values of MNCH-2 at various sampling periods. Provision of whey caused significant increase in xylose content, so that the media MNCH-9 and MNCH-10 attained 3.77 and 4.74 folds of the
pentose sugar, respectively, as compared to the value obtained for the MNCH-2. Likewise, much elevated levels of proteins and lipids were found in the culture fluids of MNCH-9 and MNCH-10 as compared to the corresponding figures for the MNCH-2. Cellulase activities of cultivated MNCH-9 and MNCH-10 turned out to be 5.75 folds higher at first sampling period as compared to the value obtained for MNCH-2 culture. At 12th day of the fermentation, MNCH-9 culture fluid showed more than 30% higher
ethanol content as compared to the yield obtained in case of MNCH-2. The MNCH-10 expressed ethanol even less than the value found for the MNCH-2. Conclusively, blending of processed whey to sugarcane
bagasse is very useful for obtaining yields of the different products including cell mass and ethanol as compared to the cultivation of the B. cereus NB-19 in media containing only bagasse or whey. These
results dictate the importance of blending agro-industrial wastes of varying nature for their efficient and economical upgradation tied up with the selection of suitable microorganism(s). Such trends are likely to gain more attention of the scientists in related areas.