Studies on bio-ethanol production using fermentation by free and immobilized yeast cells

  • P Manasa
  • Narasimhulu Korrapati Department of Biotechnology, National Institute of Technology Warangal, Telangana-506004, India.
  • Paramjeet Saroj
Keywords: Immobilized cells, fermentation, recyclability, alginate, bioethanol, glucose.

Abstract

Background: Production of bioethanol from yeast cells is very important to meet the energy crisis and this work mainly concentrated on bioethanol production by free and immobilized yeast cells.Methods: Batch fermentation with free and immobilized yeast cells was done and compared.Result: The maximum concentration of ethanol was reached around 48 h which was 30.02 gL-1 and 28.78 gL-1 for S.cerevisiae and Baker’s yeast respectively. The maximum ethanol concentrations for each sets were 30.5 gL-1, 27.6 gL-1, and 28.2 gL-1 for subsequent sets of immobilized S.cerevisiae and 28.2 gL-1, 27.6 gL-1, and 26.98 gL-1for subsequent sets of immobilized baker’s yeastConclusion: As the total time for immobilized cells experiments was 3 sets of 56 h each or 168 h, it shows the stability of cells and longer functional period. However, as the ethanol concentration was stagnant after 8h, one must reduce the time period of set readings to 4h or 6h. However, the maximum ethanol concentration was observed after 48h from the inoculation of the culture in all the cases which shows a promising time period to be targeted industrially. In conclusion, the immobilized cells have significant advantage over free cells using sodium alginate as the immobilizing agent. More research focused on the size, cell density and industrial scale studies using packed bed or tubular reactor must be done to analyze it better.  DOI: 10.21276/AABS.1508

Author Biography

Narasimhulu Korrapati, Department of Biotechnology, National Institute of Technology Warangal, Telangana-506004, India.
Biotechnology, Assistant Professor

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Published
2017-07-11
Section
Original Article