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Techniques for the Evolution of Robust Pentose-fermenting Yeast for Bioconversion of Lignocellulose to Ethanol
Published on: October 24, 2016
Assimilation of lemonade-processing wastewater by yeasts
1Department of Food Science and Technology, New York State Agricultural Experiment Station, Cornell University, Geneva, New York 14456.
Applied and Environmental Microbiology
|February 1, 1980
Summary
Candida utilis and Saccharomyces fragilis yeasts efficiently reduced biological oxygen demand in wastewater. These yeasts achieved high cell yields, with Saccharomyces fragilis showing faster settling properties.
Area of Science:
- Microbiology
- Environmental Science
- Biotechnology
Background:
- Wastewater treatment often relies on biological methods.
- Yeast fermentation is a potential avenue for bioremediation.
- Lemonade processing generates wastewater with high biological oxygen demand.
Purpose of the Study:
- To evaluate the efficacy of different yeast species in treating lemonade processing wastewater.
- To determine optimal yeast strains for high cell yield and efficient biological oxygen demand reduction.
Main Methods:
- Shake-flask studies were conducted at 30 degrees C.
- Five species of yeasts were examined.
- Wastewater was fortified with ammonium sulfate and potassium phosphate.
Main Results:
- Candida utilis and Saccharomyces fragilis yielded >2.5 g/liter of cells within 32 hours.
- Both species reduced approximately 87% of the biological oxygen demand.
- Saccharomyces fragilis exhibited more rapid settling compared to Candida utilis.
Conclusions:
- Candida utilis and Saccharomyces fragilis are effective candidates for treating lemonade processing wastewater.
- Saccharomyces fragilis offers an advantage due to its faster settling rate.
- Nutrient fortification enhanced yeast performance in bioremediation.
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