Range Of Fermentation Products PDF

Range of Fermentation Products Fermentation is the process in which the chemical transformation of organic substances into simpler compounds carried out by the action of bio-catalysts (enzymes) produced by microorganisms like bacteria, molds or yeasts. The Ranges of Fermentation Processes There a...

Range of Fermentation Products Fermentation is the process in which the chemical transformation of organic substances into simpler compounds carried out by the action of bio-catalysts (enzymes) produced by microorganisms like bacteria, molds or yeasts. The Ranges of Fermentation Processes There are five ranges of fermentation process : 1. Processes that produce microbial cells (biomass) as the products 2. Processes that produce microbial metabolites 3. Processes that produce microbial enzymes 4. Processes that produce recombinant products 5. Processes that modify substrates (transformation process) Production of biomass Microbial cells or biomass is sometimes the intended product of fermentation. Examples include single cell protein, biofertilizers, baker’s yeast, lactobacillus, and others. In the case of single-cell protein, algae is grown in large open ponds which allow photosynthesis to occur. Single-cell proteins (SCP) or microbial proteins refer to edible unicellular microorganisms. The biomass or protein extract from pure or mixed cultures of algae, yeasts, fungi or bacteria may be used as an ingredient or a substitute for protein-rich foods, and is suitable for human consumption or as animal feeds. As of today, SCP is commonly grown on agricultural waste products, and as such inherits the ecological footprint and water footprint of industrial agriculture. Production of extracellular metabolites Metabolites can be divided into two groups: a) those produced during the growth phase of the organism, called primary metabolites and b) those produced during the stationary phase, called secondary metabolites. Some examples of primary metabolites are ethanol, citric acid, glutamic acid, lysine, vitamins and polysaccharides. Some examples of secondary metabolites are penicillin, cyclosporin A, gibberellin, and lovastatin. Primary metabolites Primary metabolites are compounds made during the ordinary metabolism of the organism during the growth phase. A common example is ethanol or lactic acid, produced during glycolysis. Citric acid is produced by some strains of Aspergillus niger as part of tthe citric acid cycle to acidify their environment and prevent competitors from taking over. Glutamate is produced by some Micrococcus species, and some Corynebacterium species produce lysine, threonine, tryptophan and other amino acids. All of these compounds compounds are produced during the normal metabolism of the cell and released into the medium. Therefore no need to rupture the cells for product recovery. Secondary metabolites Secondary metabolites are compounds made in the stationary phase; penicillin, for in instance, prevents the growth of bacteria which could compete with Penicillium molds for resources. Some bacteria, such as Lactobacillus species, are able to produce bacteriocins which prevent the growth of bacterial competitors as well. These compounds are of obvious value to humans wishing to prevent the growth of bacteria, either as antibiotics or as antiseptics (such as gramicidin S). Fungicides, such as griseofulvin are also produced as secondary metabolites. Typically secondary metabolites are not produced produced in the presence of glucose or other carbon sources which would encourage growth,] and like primary metabolites are released into the surrounding medium without rupture of the cell membrane. Production of microbial enzymes Of primary interest among the intracellular components are microbial enzymes: catalase, amylase, protease, pectinase, cellulase, hemicellulase, lipase, lactase, streptokinase and many others. Enzymes are the bio-catalysts catalysts playing an important role in all stages of metabolism and biochemical emical reactions. Certain enzymes are of special interest and are utilized as organic catalysts in numerous processes on an industrial scale. Microbial enzymes are known to be superior enzymes obtained from different microorganisms, particularly for applications in industries on commercial scales. Many enzymes from microbial sources are already being used in various commercial processes. Selected microorganisms including bacteria, fungi and yeasts have been globally studied for the bio-synthesis of economically viable preparations of various enzymes for commercial applications. Production of Recombinant proteins Recombinant proteins, such as insulin, hepatitis B vaccine, interferon, granulocyte colony- stimulating factor, streptokinase and others are also made this way. The largest difference between this process and the others is that the cells must be ruptured (lysed) at the end of fermentation, and the environment must be manipulated to maximize the amount of the product. Furthermore, the product (typically a protein) must be separated from all of the other cellular proteins in the lysate to be purified. Biotransformation Biotransformation means chemical alteration of chemicals such as nutrients, amino acids, toxins, and drugs in the body. It is also needed to render non-polar compounds polar so that they are not reabsorbed in renal tubules and are excreted. Biotransformation of xenobiotics can dominate toxicokinetics and the metabolites may reach higher concentrations in organisms than their parent compounds. One example is the industrial production of cortisone, which one step is the bioconversion of progesterone to 11-alpha-Hydroxyprogesterone by Rhizopus nigricans. Another example is the bioconversion of glycerol to 1,3-propanediol, which is part of scientific research for many decades.