Removal of Bacterial Contamination from Bioethanol Fermentation System Using Membrane Bioreactor

A major issue hindering efficient industrial ethanol fermentation from sugar-based feedstock is excessive unwanted bacterial contamination. In industrial scale fermentation, reaching complete sterility is costly, laborious, and difficult to sustain in long-term operation. A physical selective separa...

Full description

Saved in:
Bibliographic Details
Published in:Fermentation (Basel) 2018-10, Vol.4 (4), p.88
Main Authors: Mahboubi, Amir, Cayli, Beray, Bulkan, Gülru, Doyen, Wim, De Wever, Heleen, Taherzadeh, Mohammad
Format: Article
Language:English
Subjects:
Antibiotics
Bacteria
bacterial decontamination
Biofuels
Bioreactors
Cell culture
Contamination
Decontamination
Economics
Ethanol
Fermentation
Filtration
Glucose
Inoculum
membrane bioreactor
Membranes
Metabolism
Metabolites
Microorganisms
Mixed culture
Pore size
Raw materials
Sterility
Turbidity
Yeast
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A major issue hindering efficient industrial ethanol fermentation from sugar-based feedstock is excessive unwanted bacterial contamination. In industrial scale fermentation, reaching complete sterility is costly, laborious, and difficult to sustain in long-term operation. A physical selective separation of a co-culture of Saccharomyces cerevisiae and an Enterobacter cloacae complex from a buffer solution and fermentation media at dilution rates of 0.1–1 1/h were examined using an immersed membrane bioreactor (iMBR). The effect of the presence of yeast, inoculum size, membrane pore size, and surface area, backwashing and dilution rate on bacteria removal were assessed by evaluating changes in the filtration conditions, medium turbidity, and concentration of compounds and cell biomass. The results showed that using the iMBR with dilution rate of 0.5 1/h results in successful removal of 93% of contaminating bacteria in the single culture and nearly complete bacteria decontamination in yeast-bacteria co-culture. During continuous fermentation, application of lower permeate fluxes provided a stable filtration of the mixed culture with enhanced bacteria washout. This physical selective separation of bacteria from yeast can enhance final ethanol quality and yields, process profitability, yeast metabolic activity, and decrease downstream processing costs.
ISSN:2311-5637
2311-5637
DOI:10.3390/fermentation4040088