Microbial fuels Fermentative fuel production

The potential use of immobilised cells in fermentation processes for fuel production has been described previously. If intact microbial cells are directly immobilised, the removal of microorganisms from downstream product can be omitted and the loss of intracellular enzyme activity can be kept to a minimum level.11... 

The development of bioreactor systems for the production of large-volume chemicals (see Chapter 3) could be the basis for reconsidering the production of biomass in limited quantities for fuel uses. This would require efficient microbial organisms to catalyze fermentation, digestion, and other bioconversion processes, as well as efficient separation methods to recover fuel products from process streams. 

Following antibiotics production, microbial industrial fermentations have been used for the production of different metabolites endogenously produced by microorganisms, e.g., enzymes for different applications and large-scale production of bioethanol for fuel usage. 

Oh, S. E., Logan, B. E. (2005). Hydrogen and electricity production from a food processing wastewater using fermentation and microbial fuel cell technologies. Water Research, 39, 4673-4682. 

Wang, A., et al. (2011). Integrated hydrogen production process from cellulose by combining dark fermentation, microbial fuel cells, and a microbial electrolysis cell. Bioresource Technology, 102, 4137—4143. 

Microbial fuels can be sorted into four classes according to the pathway that was taken in their production fermentative short-chain alcohols, nonfermentative short-chain alcohols, isoprenoid-derived hydrocarbons and fatty acid-derived hydrocarbons (Rude and Schirmer 2009). 

Microorganisms have been identified and exploited for more than a century. The Babylonians and Sumerians used yeast to prepare alcohol. There is a great history beyond fermentation processes, which explains the applications of microbial processes that resulted in the production of food and beverages. In the mid-nineteenth century, Louis Pasteur understood the role of microorganisms in fermented food, wine, alcohols, beverages, cheese, milk, yoghurt and other dairy products, fuels, and fine chemical industries. He identified many microbial processes and discovered the first principal role of fermentation, which was that microbes required substrate to produce primary and secondary metabolites, and end products. 

Whey permeate may also be fermented anaerobically to fuel gas. Studies have also been reported on the production of ammonium lactate by continuous fermentation of deproteinized whey to lactic acid followed by neutralization with ammonia. Conversion of whey and whey permeate to oil and single-cell protein with strains of Candida curvata and Trichosporon cutaneum have been examined. Production of the solvents n-butanol and acetone by Clostridium acetobutylicum or C. butyricum is under investigation in New Zealand. Whey permeate also has potential for citric acid and acrylic acid manufacture. Extracellular microbial polysaccharide production from whey permeate has... 

Growth of Renewable Resources. There are already large industries, associated with corn processing and food manufacture that utilize enzymes and microbial fermentation on an extremely large scale, In these cases, production and substrate costs can be 70% of the total product costs, and cost efficient engineering becomes paramount. The development of the industry that produces fuel grade ethanol, used as a nonleaded octane... 

There are already several examples of chemicals being produced by microbial fermentation of engineered cell factories, whose production through metabolic engineering has been boosted by the use of genomics tools, e.g., 1,3-propanediol used for polymer production, riboflavin used as a vitamin, and 7-aminodeacetoxy-cephalosporanic acid (7-ADCA) used as a precursor for antibiotics production. Furthermore, in the quest to develop a more sustainable society, the chemical industry is currently developing novel processes for many other fuels and chemicals, e.g., butanol, to be used for fuels, organic acids to be used for polymer production, and amino acids to be used as feed. 

Bioethanol produced from pretreatment and microbial fermentation of biomass has great potential to become a sustainable transportation fuel in the near future [1]. Brazil and the United States are the largest producers of ethanol for transport, accounting for about 90% of world production. Both coimtries currently produce about 16 billion liters per year with a displacement of 40% of gasoline use in Brazil but only 3% in the United States with... 

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