Fermentation plant-sourced products

Figure 9.10 Flow chart of an ethanol fermentation plant. (Source United States. National Agricultural Library Office of Alcohol Fuels Solar Energy Research Institute. Fuel from Farms A Guide to Small-Scale Ethanol Production. Golden, Colo. Technical Information Office, Solar Energy Research Institute, 1982 published at www //dnr.state.Ia.us.)...

The main question is whether synthesis of PHA in plants can succeed in bringing the cost of the polymer down to the range of 0.5 -1 US /kg. Bacterial production of PHA typically relies on a carbon source, such as sucrose or glucose, which is produced from photosynthesis and extracted from plants. Synthesis of PHA directly in plants would, therefore, represent a saving in terms of the number of intermediary steps linking C02 fixation to PHA production. Furthermore, starch is one of the cheapest plant commodity product on the market, at about 0.25 US /kg [86]. It is, thus, likely that the production cost of PHA in plants will be substantially cheaper than bacterial fermentation. The final cost of producing PHA in plants will depend on a number of factors. 

The abundance and nontoxic nature of carbon dioxide also make it an attractive carbon feedstock. Potential sources of carbon dioxide include the atmosphere (where it is present in concentrations of approximately 370 ppm), natural reservoirs including natural gas wells and pure CO2 wells, waste streams of fermentation reactions, and flue stacks from power plants, cement production, and so on. Because CO2 is not toxic, development of chemical processes in which CO2 can be used to... 

Hydrolases were in the first catalogue after the company was founded in 1950 but, not surprisingly, the chiral molecules originated mainly from the chiral pool. The first biocatalytic reactions were developed with kidney acylases and later with esterases and lipases, in the beginning mainly animal-derived biocatalysts [10], The set-up of in-house biocatalyst production from microbial and plant sources as well as the construction of a new biotechnology laboratory with ten fermenters of up to 300 L total volume, allow the development and production of improved biocatalysts and for them to be applied in the asymmetric synthesis of laboratory chemicals. There are today more than 100 biocatalytic processes in routine production and a project management team is handling custom biotransformations. 

Ethanol is the alcohol of alcoholic beverages and is prepared for this purpose by fermentation (Section 12.9) of carbohydrates (starch, sugars) from a wide variety of plant sources (Table 14.4). The growth of yeast is inhibited at alcohol concentrations higher than about 14%, and fermentation comes to a stop. Beverages with a higher ethanol concentration are prepared either by distillation or by fortification with ethanol that has been obtained by the distillation of another fermentation product. The maximum concentration of ethanol that can be obtained by distillation of ethanol—water mixtures is... 

Starch is a renewable carbon source abundantly available from plant sources. However, it is usually hydrolysed to glucose via a two-step process, liquefaction and saccharification, before adding it into the polymer prodnction medium [26]. Kim [27] reported P(3HB) production from starch using Azotobacter chroococcum via a fed-batch fermentation. A PHA content of 46 and 20 wt% with a CDW of 54 g/1 and 71 g/1 were obtained with and without oxygen limitation, respectively. A halophilic bacterinm, Haloferax mediterrane was also reported to be able to produce P(3HB) from starch, but the strain was not favourable due to the salt required for its growth which contributed significantly to the PHA manufacturing cost. 

Owing to immense competition between microbial and plant polysaccharides for industrial applications, various advance techniques and methodologies have been explored by several researchers to explore flieir stmctural backbone and their associated biological functions. Development of plant polysaccharides is comparatively cheap, while it is uncontrolled and takes place for a short span in a year. On the contrary, microbial polysaccharides production is well regulated and can be sustained fliroughout the year. Nevertheless, fermentation procedures for fabrication of cheap (from plant sources) polysaccharides are not advisable. 

Polyethylene terephthalate (PET) plastic can also be made from plant sources. PET is typically produced from terephthalic acid and monoethylene glycol (MEG) that are made from petroleum products. MEG can also be fermented from sugarcane, corn, soy, or other organic ingredient. Biobased PET, then, can be produced with approximately 30% from organic sources and 70% from petroleum sources. Coca-Cola, Eord Motor, Heinz, Nike, and Proctor Gamble combined forces in a consortium to develop a 100% plant-based PET product. The plant-based PET consortium will collaborate on PET research projects... 

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. 

The monomers used in the polycondensation reaction for the production of poly(alkylene dicarboxylate)s are basically from petrochemical sources. However, some of them can be obtained from renewable sources. For example, 1,3-propanediol can be produced by fermentation of glycerol, which is a by-product from biodiesel or plant oil production. Succinic acid can be synthesized from glucose or whey by bacterial fermentation in very high yields. ... 

Projects to use biomass as an energy source are numerous. Only those that make use of by-products/wastes of certain bio-based processes within the own fence appear to be realistic in terms of economics. Examples are wood wastes, sueh as saw dust used in the power stations of wood processing plants (saw and paper mills) lignin and hemicellulose wastes in paper pulping plants slop (vinage), which is used to make biogas in fermentation plants straw or other wastes of farming. 

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