UBC Theses and Dissertations
Potential of spent sulfite liquor as raw material for production of vitamin B12 by certain species of lactobacillus, propionibacteria, and streptomyces Truong, Thieu Long
Spent sulfite liquor is suitable for growth of Propionibacteria freudenreichii, Propionibacteria shermanii, and Lactobacillus plantarium but not for Streptomyces griseus and Streptomyces olivaceus. L. plantarium and P. freudenreichii together, in fermentations of two stages or of one stage with mixed culture, are poor in serving the ultimate goal of producing vitamin B12 in substantial quantity. P. shermanii is not as good a producer of vitamin B12 from SSL as P. freudenreichii alone. Fermentations of SSL with P. freudenreichii show a net increase in market value of the broth. They should be done in two stages, the first anaerobic and the second aerobic. The optimum requirements are 5g/l of yeast extract as essential nitrogen source and 1ppm of cobalt ions as precursor. The optimum yield in vitamin B12 is 1.5mg/l, accompanied by the production of 0.14 moles/1 of volatile acids. 5,6-dimethyl benzimidazole is found to be beneficial to the yields of cells, of vitamin B12 and of volatile acids. Fish plant effluent is not a suitable replacement for yeast extract. The reduction of the polluting potential of SSL, accomplished by these fermentations, is only about 14% of the total chemical oxygen demand. This reduction is due to the removal of about 70% of the reducing sugars, transformed to cells and volatile acids. These sugars originally contribute a polluting potential of 20% of the total COD to SSL.
Item Citations and Data