Biodegradation of Spent Wash Using Bacteria and Yeast

Biodegradation of spent wash was studied. Different pH used for biodegradation of spent wash. Total 30 microbial cultures (17 bacterial and 13 yeast) used for screening of spent wash (SW) biodegradation. 16 cultures have not shown decolorization of spent wash. P. testosteronii NCIM 5098 and S. cerevisiae NCIM 3077 have shown 17.69 and 16.52 % decolorization respectively. P. testosteronii NCIM 5098 has shown maximum 17.69 % decolorization at pH 4.5. Various chemicals used for precipitation of spent wash. 1.5% Ca(OH)2 found useful for precipitation. The solution obtained after separation of precipitate used for screening. 23 cultures (12 bacterial and 11 yeast) were used for biodegradation of spent wash at pH 8. Pseudomonas syringae NCIM 5102 and Pseudomonas sp. NCIM 2223 have shown 36.72% and 36.25% decolorization respectively. From the study of screening at pH 8.0, four cultures were selected for further work at pH 6.0. Candida utilis NCIM 3055 and Pseudomonas sp. 2223 have shown 26.78 % and 27.56% decolorization at pH 6.0 respectively where the colour of spent wash decreased substantially. Candida utilis NCIM 3055 has shown sugar consumption but Pseudomonas sp. NCIM 2223 has not. Therefore, Candida utilis NCIM 3055 is the best culture for biodegradation of spent wash.