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Equipment and processes of biotechnological industry  09.12.2019 11:00

In general, biotechnology is application of living organisms or substances produced by them for any purposes such as food, medical, agricultural purposes, etc. Classic biotechnology including such traditional processes as fermentation and reproduction of microorganism cultures gradually gives way to laboratory biotechnology. Today biotechnology has achieved high success in its development and continues to develop very rapidly but to a great extent the development is directed to more science intensive and molecular processes leaving traditional biotechnological processes such as brewing, wine-making, lactate products manufacturing, alcohol production and yeast manufacturing far behind.

Nevertheless, now these traditional biotechnological manufacturing plants are widely available and continue to develop. All these processes are based on vital functions of microorganisms such as bacteria and fungi. For example, lactic acid bacteria are used for production of kefir, fermented baked milk, yoghurts and other lactic acid products. Basic raw material for manufacturing such products is milk that is processed at pasteurization and separation stages. After these stages lactic acid bacteria are added to pasteurized and separated milk and these bacteria perform fermentation process. Lactic acid products are produced because of the fermentation. Main equipment for manufacturing lactic acid products includes fermentation vessels, raw material storage vessels and finished products storage vessels, curd and cheese vats, production lines for active cultures, brine vats, refrigerating units.

At yeast manufacturing plants various raw materials are used, but molasses is mostly applied. Primary production of culture medium (yeasts) is performed in continuous mode: firstly yeasts are reproduced in a small retort, then after achieving the specified concentration the culture medium is transferred to a larger vessel where yeasts are reproduced once again and after achieving the specified concentration once again are transferred to an even greater vessel and so on till they are fed to a yeast production vessel. At yeast manufacturing plants the following equipment is applied: heat exchangers, separators and equipment for yeast drying such as film drum dryers and spray dryers. In addition, freeze drying of yeasts is possible. Lyophilizers are used for the process.

At alcohol manufacturing plants where alcohol is produced with the use of traditional microbiological methods and not by chemical synthesis, mostly grain is used as feed. Firstly, grain shall be subject to pretreatment. First of all it shall be cleaned from mechanical impurities. This shall be performed with the use of such vessels as sieves and separators. Then cleaned grain is fed to boiling vessels where fuller recovery of starch and sacchariferous components is performed. Then boiled feed mass is sent to settling tanks and hydrolyzers where saccharification of feed mass is taking place. So pretreated feed is sent to fermenters where it is fermented to alcohol-containing liquid (brew) as a result of vital functions of microorganisms. Alcohol recovery is performed in a distiller and then produced alcohol is purified with the use of another fractionation column. So produced alcohol is quite purified and can be used for production of alcoholic beverage products and in medicine.

At breweries malt is used as feed. As a result of its fermentation and addition of other components (first of all hops) beer is produced. Main equipment of breweries includes fermenters, heat exchangers, separators, settling tanks and refrigerating units. Furthermore, a large territory at breweries is occupied by a unit of packing preparation and finished product bottling where glass and plastic packing is subject to washing, antiseptic treatment, finished beer pouring, capping and label attaching. Usually as production capacities at breweries are big, units for packing preparation and beer bottling are highly automated. Therefore, this makes it possible to significantly increase labour productivity and reduce product cost.

Wine-making is one of the most prolonged biotechnological processes. Grapes or products of their treatment are used as feed for wine-making. The manufacturing includes feed preparation process, fermentation process, separation, settling, packing preparation and finished product bottling. All processes specified above are applied during producing table wine. While producing vintage wine it shall be aged during defined years in special wooden casks. Wine-making is a fine process and everything is important for it, from grapes cultivar to aging conditions. Only in case of observance of all process conditions it is possible to produce high-quality wine.

One of the main product of biotechnological industry is pharmaceutical drugs manufactured with the use of biotechnological processes. Biotechnological industry produces antibiotics, ferment drugs, amino acids including essential amino acids, interferons, insulin, vaccines and serums against various diseases (influenza, diphtheria, tetanus, rubella, mumps, measles, pertussis, herpes diseases, chickenpox, encephalitis, etc.). These manufacturing plants have rather complex equipment arrangement related not only with manufacturing technology features but also with necessity of observing specified sanitary and hygienic requirements. Manufacturing plants that meet the requirements specified above completely are usually certified according to GMP (Good Manufacturing Practice) international standard. These processes of producing mentioned drugs are very different but they all are based on growth and reproduction of biological material such as bacteria, fungi and viruses. Usually during manufacturing auxiliary biological materials are used as a substratum for microorganisms as well as for recovery of finished products: hen’s eggs, animal red corpuscles. Processes of growth and reproduction of biological material are usually performed in special vessels (fermenters) where simultaneously mixing of culture medium, air supply, saturation of culture medium with air and maintaining of constant temperature suitable for the most optimal growth rate of microorganisms are ensured. In addition, culture medium contains nourishment sources for microorganisms. Firstly there should be sources of carbon, phosphorus and nitrogen for building of cells by microorganisms. Usually at the manufacturing plants there is a section of culture medium preparation before its loading to fermenters. The fermentation process shall be performed in continuous or batch modes. In continuous mode substratum is constantly fed to a fermenter and culture medium is constantly taken off the fermenter. In batch mode substratum is not added during fermentation and culture medium is discharged after fermentation ending. After fermentation culture medium is separated with the use of the following methods: separation, centrifuging or settling performed in separators, centrifuges or settling tanks accordingly. Then additional treatment is performed with the required medium (either culture medium separated from microorganisms or microorganisms separated from culture medium). During the subsequent processing various methods such as thermolysis (destruction of cell membrane in case of high temperature application), use of chemical substances destructing cell membrane to recover cell components, extraction, chromatography, sedimentation and so on are applied. Therefore, the following equipment is used: extractors, chromatographic columns, precipitators, filters, centrifuges, thermostats and other vessels.

Another modern biotechnological field is genetic engineering. It is a biotechnological area that performs implementation of any modifications in DNA (genome) structure of microorganisms. After it became possible to operate with DNA at molecular level, recover it, cut specified areas, study its structure (in order to do that polymerase chain reaction (PCR) is applied; the process of DNA structure studying is called sequencing), intensive work and researches regarding implementation of genome modifications were started. So genetically modified organisms were created. Genetically modified organisms are organisms with DNA structure modified artificially, for example, DNA of bacteria synthesizing prototoxin protein was added to potato DNA to prevent eating potato bushes by Colorado potato beetle. This protein is entered to Colorado potato beetle with leaves and in its body it transforms to a toxin that results in beetle poisoning. This prototoxin does not act on a human body because in human stomach it does not transform to toxic substance. Therefore, we can note that modifications in the genome of organisms make it possible to change their characteristics and features and for the most part they are positive changes. On the other hand, the issue related to genetically modified organisms consists in the fact that currently we have no sufficient information available regarding consequences of artificial modifications in living organism genomes.  DNA inserted with the use of methods of genetic engineering is transferred to many other organisms by reproduction, it results in wide distribution of modified DNA in nature, and interference of man in nature can always be negative because it can violate the fragile balance formed in nature during many thousands of years.

The most well-known method of genetic engineering is cloning. In one’s time the sheep Dolly made a big sensation all over the world. Cloning is a complex technology of creating a new living organism with a genome that is identical to a genome of a specified living organism. Cloning challenge is based on the fact that during cloning of one organism many other organisms having genetic deviations (mutations) are created. These organisms with such mutations are defective from natural point of view. Therefore, in one’s time in many countries researches regarding human cloning were stopped.

So biotechnology is a complex and versatile science and it widely develops now creating new pharmaceutical drugs, studying molecular and genetic reasons for diseases and adding essential changes in our lives even today.