Solventogenesis is the biochemical production of solvents (usually acetone and butanol) by Clostridium species. [1] It is the second phase of ABE fermentation. [2]
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Solventogenesis is the biochemical production of solvents (usually acetone and butanol) by Clostridium species. [1] It is the second phase of ABE fermentation. [2]
Solventogenic Clostridium species have a biphasic metabolism composed of an acidogenic phase and a solventogenic phase. During acidogenesis, these bacteria are able to convert several carbon sources into organic acids, commonly butyrate and acetate. [2] As acid accumulates, cells begin to assimilate the organic acids to solvents. In Clostridium acetobutylicum , a model solventogenic Clostridium species, a combination of low pH and high undisociated butyrate, referred to as the "pH-acid effect", triggers the metabolic shift from acidogenesis to solventogenesis. [3]
Acetone, butanol, and ethanol are the most common products of solventogenesis. Some species such as Clostridium beijerinckii , Clostridium puniceum and Clostridium roseum are able to further reduce acetone to isopropanol. Several species are able to produce additional solvents under various culture conditions. For example, glycerol fermentation results in the production of 1,3-propanediol in several species. Acetoin is produced by several species and is further reduced to 2,3-butanediol by Clostridium beijerinckii. [4]
In chemistry, alcohol is an organic compound that carries at least one hydroxyl functional group (−OH) bound to a saturated carbon atom. The term alcohol originally referred to the primary alcohol ethanol (ethyl alcohol), which is used as a drug and is the main alcohol present in alcoholic beverages. An important class of alcohols, of which methanol and ethanol are the simplest members, includes all compounds for which the general formula is CnH2n+1OH. Simple monoalcohols that are the subject of this article include primary (RCH2OH), secondary (R2CHOH) and tertiary (R3COH) alcohols.
Butanol (also called butyl alcohol) is a four-carbon alcohol with a formula of C4H9OH, which occurs in five isomeric structures (four structural isomers), from a straight-chain primary alcohol to a branched-chain tertiary alcohol; all are a butyl or isobutyl group linked to a hydroxyl group (sometimes represented as BuOH, n-BuOH, i-BuOH, and t-BuOH). These are n-butanol, 2 stereoisomers of sec-butanol, isobutanol and tert-butanol. Butanol is primarily used as a solvent and as an intermediate in chemical synthesis, and may be used as a fuel. Biologically produced butanol is called biobutanol.
Butyric acid (from Ancient Greek: βούτῡρον, meaning "butter"), also known under the systematic name butanoic acid, is a straight-chain alkyl carboxylic acid with the chemical formula CH3CH2CH2CO2H. It is an oily, colorless liquid with an unpleasant odor. Isobutyric acid (2-methylpropanoic acid) is an isomer. Salts and esters of butyric acid are known as butyrates or butanoates. The acid does not occur widely in nature, but its esters are widespread. It is a common industrial chemical and an important component in the mammalian gut.
Clostridium is a genus of Gram-positive bacteria. This genus includes several significant human pathogens, including the causative agents of botulism and tetanus. The genus formerly included an important cause of diarrhea, Clostridioides difficile, which was separated after 16S rRNA analysis. They are obligate anaerobes capable of producing endospores. The normal, reproducing cells of Clostridium, called the vegetative form, are rod-shaped, which gives them their name, from the Greek κλωστήρ or spindle. Clostridium endospores have a distinct bowling pin or bottle shape, distinguishing them from other bacterial endospores, which are usually ovoid in shape. Clostridium species inhabit soils and the intestinal tract of animals, including humans. Clostridium is a normal inhabitant of the healthy lower reproductive tract of females.
The Clostridia are a highly polyphyletic class of Firmicutes, including Clostridium and other similar genera. They are distinguished from the Bacilli by lacking aerobic respiration. They are obligate anaerobes and oxygen is toxic to them. Species of the class Clostridia are often but not always Gram-positive and have the ability to form spores. Studies show they are not a monophyletic group, and their relationships are not entirely certain. Currently, most are placed in a single order called Clostridiales, but this is not a natural group and is likely to be redefined in the future.
Clostridium acetobutylicum, ATCC 824, is a commercially valuable bacterium sometimes called the "Weizmann Organism", after Jewish-Russian-born Chaim Weizmann. A senior lecturer at the University of Manchester, England, he used them in 1916 as a bio-chemical tool to produce at the same time, jointly, acetone, ethanol, and butanol from starch. The method has been described since as the ABE process,, yielding 3 parts of acetone, 6 of butanol, and 1 of ethanol. Acetone was used in the important wartime task of casting cordite. The alcohols were used to produce vehicle fuels and synthetic rubber.
Acetone, or propanone, is an organic compound with the formula (CH3)2CO. It is the simplest and smallest ketone. It is a colourless, highly volatile and flammable liquid with a characteristic pungent odour.
tert-Butyl alcohol, also called tert-butanol or t-butanol, is the simplest tertiary alcohol, with a formula of (CH3)3COH (sometimes represented as t-BuOH). It is one of the four isomers of butanol. tert-Butyl alcohol is a colorless solid, which melts near room temperature and has a camphor-like odor. It is miscible with water, ethanol and diethyl ether.
Acidogenesis is the second stage in the four stages of anaerobic digestion:
1-Butanol (IUPAC: Butan-1-ol) also known as n-Butanol is a primary alcohol with the chemical formula C4H9OH and a linear structure. Isomers of 1-Butanol are isobutanol, 2-butanol, and tert-butanol. The unmodified term butanol usually refers to the straight chain isomer.
Butanol may be used as a fuel in an internal combustion engine. It is more similar to gasoline than it is to ethanol. A C4-hydrocarbon, butanol is a drop-in fuel and thus works in vehicles designed for use with gasoline without modification. It can be produced from biomass as well as fossil fuels. Both biobutanol and petrobutanol have the same chemical properties. Butanol from biomass is called biobutanol.
Fermentation is a metabolic process that produces chemical changes in organic substrates through the action of enzymes. In biochemistry, it is narrowly defined as the extraction of energy from carbohydrates in the absence of oxygen. In food production, it may more broadly refer to any process in which the activity of microorganisms brings about a desirable change to a foodstuff or beverage. The science of fermentation is known as zymology.
Acetoacetate decarboxylase is an enzyme involved in both the ketone body production pathway in humans and other mammals, and solventogenesis in bacteria. Acetoacetate decarboxylase plays a key role in solvent production by catalyzing the decarboxylation of acetoacetate, yielding acetone and carbon dioxide.
Acetone–butanol–ethanol (ABE) fermentation is a process that uses bacterial fermentation to produce acetone, n-Butanol, and ethanol from carbohydrates such as starch and glucose. It was developed by chemist Chaim Weizmann and was the primary process used to produce acetone, which was needed to make cordite, a substance essential for the British war industry during World War I.
In enzymology, a butyrate kinase is an enzyme that catalyzes the chemical reaction
Clostridium beijerinckii is a gram positive, rod shaped, motile bacterium of the genus Clostridium. It has been isolated from feces and soil. Produces oval to subterminal spores. it is named after Martinus Beijerinck who is a Dutch bacteriologist.
In industrial paper-making processes, organosolv is a pulping technique that uses an organic solvent to solubilise lignin and hemicellulose. It has been considered in the context of both pulp and paper manufacture and biorefining for subsequent conversion of cellulose to fuel ethanol. The process was invented by Theodor Kleinert in 1968 as an environmentally benign alternative to kraft pulping.
Clostridium saccharobutylicum is an indole and notably acetone, butanol and ethanol-producing bactera, with type strain DSM 13864T. Its genome has been sequenced.
Clostridium pasteurianum is a bacterium discovered in 1890 by the Russian microbiologist Sergei Winogradsky. It was the first free living (non-symbiotic) micro-organism discovered that could fix free nitrogen from the air.
Industrial microbiology is a branch of biotechnology that applies microbial sciences to create industrial products in mass quantities, often using microbial cell factories. There are multiple ways to manipulate a microorganism in order to increase maximum product yields. Introduction of mutations into an organism may be accomplished by introducing them to mutagens. Another way to increase production is by gene amplification, this is done by the use of plasmids, and vectors. The plasmids and/ or vectors are used to incorporate multiple copies of a specific gene that would allow more enzymes to be produced that eventually cause more product yield. The manipulation of organisms in order to yield a specific product has many applications to the real world like the production of some antibiotics, vitamins, enzymes, amino acids, solvents, alcohol and daily products. Microorganisms play a big role in the industry, with multiple ways to be used. Medicinally, microbes can be used for creating antibiotics in order to treat antibiotics. Microbes can also be used for the food industry as well. Microbes are very useful in creating some of the mass produced products that are consumed by people. The chemical industry also uses microorganisms in order to synthesize amino acids and organic solvents. Microbes can also be used in an agricultural application for use as a biopesticide instead of using dangerous chemicals and or inoculants to help plant proliferation.