Industrial fermentation

Although a tremendous number of fermentation processes have been researched and developed to various extents, only a couple of hundred ate used commercially. Fermentation industries have continued to expand in terms of the number of new products on the market, the total volume (capacity), and the total sales value of the products. The early 1990s U.S. market for fermentation products was estimated to be in the 9-10 x 10 range. The total world market is probably three times that figure, and antibiotics continue to comprise a primary share of the industry. Other principal product categories are enzymes, several organic acids, baker s yeast, ethanol (qv), vitamins (qv), and steroid hormones (qv). 

The modem fermentation industries developed from the early era of antibiotics. Over 4000 antibiotics have been discovered since the 1950s. However, only about 100 are produced on a commercial scale and over 40 of these are prepared by a combination of microbial synthesis and chemical modifications. Antibiotics produced by fermentation and used as starting materials in chemical syntheses are given in Table 2. 

S. Kinoshita, Fermentation Industry, 2nd. ed, (in Japanese), Dakuhon Tosho Company, Tokyo, Japan, 1975, p. 83. 

Fusel Oils. The original source of amyl alcohols was from fusel oil which is a by-product of the ethyl alcohol fermentation industry. Refined amyl alcohol from this source, after chemical treatment and distillation, contains about 85% 3-methyl-1-butanol and about 15% 2-methyl-1-butanol, both primary amyl alcohols. Only minor quantities of amyl alcohol are suppHed from this source today. A German patent discloses a distillative separation process for recovering 3-methyl-1-butanol from fusel oil (93). 

The fermentation industry is based almost exclusively on renewable materials in the form of molasses, starch, etc. Most products are of very high value and relatively low volume such as antibiotics (qv) (23). 

Starches. In the United States, all potable alcohol, most fermentation industrial alcohol, and most fuel alcohol is currendy made principally from grains com is the principal feedstock for fuel alcohol. Fermentation of starch from grain is somewhat more complex than fermentation of sugars because starch must first be converted to sugar and then to ethanol. This process was known to the ancient Egyptians and Mesopotamians who brewed beer almost 5000 years ago (202). The simplified equations for the conversion of starch to ethanol are... 

Activities associated with bioreactors include gas/hquid contacting, on-hne sensing of concentrations, mixing, heat transfer, foam control, and feed of nutrients or reagents such as those for pH control. The workhorse of the fermentation industry is the conventional batch fermenter shown in Fig. 24-3. Not shown are ladder rungs inside the vessel, antifoam probe, antifoam system, and sensors (pH, dissolved oxygen, temperature, and the like). Note that coils may lie between baffles and the tank wall or connect to the top to minimize openings... 

Ganmgs-fShigkeit, /. fermentability. -fuselol, n. fusel oil. -gewerb(e), n. fermentation industry. 

Despite the advantages of continuous cultures, the technique has found little application in the fermentation industry. A multi-stage system is the most common continuous fermentation and has been used in the fermentation of glutamic add. The start-up of a multi-stage continuous system proceeds as follows. Initially, batch fermentation is commenced in each vessel. Fresh medium is introduced in the first vessel, and the outflow from this proceeds into the next vessel. The overall flow rate is then adjusted so that the substrate is completely consumed in the last vessel, and the intended product accumulated. The concentration of cells, products and substrate will then reach a steady state. The optimum number of vessels and rate of medium input can be calculated from simple batch experiments. 

The growth of cells on a large scale is called industrial fermentation. Industrial fermentation is normally performed in a bioreactor, which controls aeration, pH and temperature. Microorganisms utilise an organic source and produce primary metabolites such as ethanol,... 

Filter aids are widely used in die fermentation industry to improve the efficiency of filtration. It is a pre-coated filter medium to prevent blockage or blinding of the filter by solids, which would otherwise wedge diemselves into the pores of the cloth. Filter aid can be added to the fermentation broth to increase the porosity of the cake as it formed. This is only recommended when fermentation product is extracellular. Filter aid adds to the cost of filtration. The minimum quantity needed to achieve the desired result must be established experimentally. Fermentation broths can be pretreated to improve filtration characteristics. Heating to denature proteins enhances the filterability of mycelial broths such as in penicillin production. Alternatively, electrolytes may be added to promote coagulation of colloids into larger, denser particles, which are easier to filter. The filtration process is affected by the viscosity and composition of the broth, and the cell cake.5... 

The fermentation wastes Corynebacterium glutamicum biomass) were obtained in a dried powder form from a lysine fermentation industry (BASF-Korea, Kunsan, Korea). The protonated biomass was prepared by treating the raw biomass with a 1 N HNO3 solution for 24 h, thereby replacing the natural mix of ionic species with protons. The resulting C glutamicum biomass was dried and stored in a desiccator and used as a biosorbent for the sorption experiments. 

The sensor was stable up to 2 weeks and could be easily regenerated in water making it suitable for use in fermentation industries. 

Unlike both the petrochemical and fermentation industries [1, 2], stoichiometric synthesis has for many years been a satisfactory tool for the preparation of molecules for application in life science industries. In recent years, however, the timely introduction of bio- and chemocatalysis has allowed organic synthesis in the fine chemical industry to meet both higher demands in molecular complexity of its products and a better process efficiency. 

Blaine, R.K. Van Lanen, J.H. Application of waste-to-product ratios in fermentation industries. Biotech. Bioeng. 1962, IV, 129-138. 

Ko3Tincu, I. Yalcin, F. Ozturk, I. Color removal of high strength paper and fermentation industry effluents with membrane technology. Water Sci. Technol. 1999, 40 (11-12), 241-248. 

Anonymous Bull. Kyowa Fermentation Industry, Japan 1983 14, 493. 

The greatest outlet for molasses is of course in alcohol fermentation industries, but since alcohol can be produced from ethylene and from acetylene, which in turn can be produced from methane, research into other fermentations and other uses for molasses would seem to be expedient. 

Normal ammonium sulphate is used in preparing ammonia and the ammonium salts it is used as a fertilizer it has been used in purifying sulphuric acid from nitrogen oxy-compounds in the fermentation industries and in making freezing mixtures. 

Aeration is of importance in the fermentation industries. In the manufacture of baker s yeast, penicillin, and other antibiotics, an adequate air supply is required for optimum yields in certain submerged fermentation processes. 

Growth of the Amino Acid/Aciclulant Fermentation Industry... 

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