Fermentation chemical production, worldwide

The anaerobic fermentation of ethanol from sugar (Fig. 8.3) goes back to the Stone Age. In 1997, the fermentation of ethanol, mainly from sugar cane, molasses (Brazil) and corn (USA), amounted to 24 Mt worldwide, dwarfing the chemical production of 2.6 Mt a 1 [23]. Iogen (Canada) produces ethanol from... 

There are thousands of breweries worldwide. However, the number of companies using fermentation to produce therapeutic substances and/or fine chemicals number well over 150, and those that grow microorganisms for food and feed number nearly 100. Lists of representative fermentation products produced commercially and the corresponding companies are available (1). Numerous other companies practice fermentation in some small capacity because it is often the only route to synthesize biochemical intermediates, enzymes, and many fine chemicals used in minor quantities. The large volume of L-phenylalanine is mainly used in the manufacture of the artificial dipeptide sweetener known as aspartame [22389-47-0]. Prior to the early 1980s there was httle demand for L-phenyl alanine, most of which was obtained by extraction from human hair and other nonmicrobiological sources. 

The p-lactams, mainly penicillins and cephalosporins, are by production volume the most important class of antibiotics worldwide, enjoying wide applicability towards a range of infectious bacteria. Most of the key molecules are semi-synthetic products produced by chemical modification of fermentation products. Production of these molecules has contributed significantly to the development of large-scale microbial fermentation technology, and also of large-scale biocatalytic processing. 

Major biotechnological uses of the biomass carbohydrate moiety have attracted worldwide attention. Controlled cellulose degradation by cellulases may produce materials for important multifarious applications carbohydrates that can be used in the food and beverage industries, cellulose microfibril fragments for non-caloric food additives, hyperabsorbent cellulose fibers from fragmented cellulose microfibrils which can be used in biomedical, commercial and house-hold absorbent materials. Biomass-derived glucose syrups can also be used as carbon source in industrial fermentations for the production of antibiotics, industrial enzymes, amino-acids, and bulk chemicals. 

The semi-synthetic production of vitamin C is rapidly moving to a full biotech process. Vitamin C (ascorbic acid) is an important segment in the worldwide vitamin market with a market share of approximately 20 percent. Its worldwide sales amounted to around USD 0.5 bilHon in 1999. The traditional route to vitamin C is a multistep process involving chemical and fermentative steps. It starts with the catalytic hydrogenation of D-glucose to D-sorbitol, followed by the fermentative oxidation of D-sorbitol to L-sorbose, which is then converted... 

For the very large sugar exporters, worldwide demand may not keep pace with the ability to expand production so that fermentation to ethanol may provide them with a means to reduce petroleum imports and to keep sugar off the market, thus keeping world sugar prices high. But, even in this case, the use of ethanol for a fuel may not be the best economic use for the alcohol. Use of ethanol as a chemical feedstock may also be economically attractive. This topic, however, is beyond the scope of the current analysis. 

At present succinic acid is a specialty chemical with an annual production volume of about 30 000 tons worldwide. Fossil-based succinic acid is most commonly prepared via hydrogenation of maleic anhydride (by oxidation of n-butane or benzene) [73]. In the field of bio-based chemicals and building blocks succinic acid is considered to be one of the most important platform chemicals [1, 74, 75], and as a result of the introduction of biosuccinic acid the production volume is expected to double or triple within years. Several fermentation processes have been described to produce bio-based succinic acid. Common feedstocks for these processes include glucose, starch and xylose [76]. The commercial potential for bio-succinic acid is illustrated by the numerous initiatives by companies that are working towards, or already... 

Acetic acid is produced industrially both synthetically and by bacterial fermentation. Today, the biological route accounts for only about 10% of world production, but it remains important for the production of vinegar, as many nations food purity laws stipulate that vinegar used in foods must be of biological origin. About 75% of acetic acid made for use in the chemical industry is made by methanol carbonylation, explained below. Alternative methods account for the rest. Total worldwide production of virgin acetic acid is estimated at 5 Mt/a (million tonnes per year), approximately half of which... 

Ethanol was one of the first organic chemicals to be prepared and purified. Its production by fermentation of grains and sugars has been carried out for perhaps 9000 years, and its piuification by distillation goes back at least as far as the 12th century. Today, approximately 55 million metric tons (18 billion gallons) of ethanol is produced worldwide each year, most of it by fermentation of com, barley, sorghum, and other plant sources. Essentially the entire amount is used for automobile fuel. 

In 1963, synthetic lactic acid production began on a commercial scale. The chemical synthesis route for synthetic lactic acid yields a racemic mixture of Di-isomers. The commercial process is based on lactonitrile (Holten et al. 1971). Lactonitrile is produced by the base-catalyzed addition of hydrogen cyanide to acetaldehyde. Lactonitrile is then hydrolyzed by strong acid to yield lactic acid, which is purified and recovered. Today, synthetic lactic acid is produced mostly in the United States and Japan, and it accounts for about 50 % of total worldwide production. Industrial fermentations also yield about half the world s lactic acid production and thus are very competitive. 

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