Principles of Biotechnology and Object Selection
Industrial biotechnology relies on the close integration of advanced scientific developments and actual production capacities. It is based on processes such as fermentation, bioconversion (transformation of one substance into another), cultivation of biological objects, and genetic manipulation.
Despite the colossal natural biodiversity (over 100,000 species of bacteria and 250,000 fungi), about 100 species are involved in actual biotechnological production. This strict limitation is dictated by the poor understanding of the vast majority of the microbial world. Successful work with a strain requires specialized equipment, strict control at all stages, and a deep understanding of the producer's physiology.
Bacteria and Fungi as Biological Factories
In industry, different genera of microorganisms solve highly specialized tasks:
- Genus Acetobacter: oxidizes ethanol to produce acetic acid (with the release of carbon dioxide and water).
- Genus Bacillus: serves as a source of enzymes (e.g., B. subtilis) and a basis for plant protection products (B. thuringiensis).
- Genus Clostridium: used for the fermentation of sugars to form solvents — butanol, acetone, and ethanol.
- Lactic acid bacteria (Lactobacillus): indispensable in the food industry.
- Pseudomonads (P. denitrificans): used for the synthesis of vitamin B12.
- Corynebacteria (C. glutamicum): produce amino acids.
Among fungi, molds (Penicillium chrysogenum, Cephalosporium acremonium) and actinomycetes (Streptomyces spp.) play a crucial role as major antibiotic producers. Yeast is actively used in baking, brewing, and winemaking, for the synthesis of feed protein, and also serves as an important component of laboratory nutrient media.
Medical and Genetic Engineering Applications
A breakthrough in pharmacology is associated with the use of recombinant strains, where foreign genetic material has been introduced using genetic engineering methods.
- Escherichia coli has become a universal producer: it manufactures interferons, insulin, growth hormones, and various antigens.
- Bacillus subtilis also efficiently produces interferon.
- Yeast cultures are used for the industrial synthesis of interleukins and hepatitis B virus antigens.
- Recombinant viruses (e.g., vaccinia virus) act as a platform for obtaining viral antigens.
In addition to modified strains, native pathogenic, opportunistic, or vaccine strains are also used. They are necessary for the production of diagnostic agents, immunoglobulins, probiotics, and phage preparations.
Plant and Animal Cell Cultures
When microorganisms cannot synthesize complex molecules, isolated cell cultures are used.
Plant cells have become a scalable alternative to harvesting wild raw materials (for example, ginseng cell cultivation technology has been perfected). They synthesize opiates, alkaloids, vitamins, and enzymes, as well as preparations of various groups (diuretics, cardiac, antitumor). The obtained substances are completely biologically equivalent to components from whole plants.
Animal cells are used to obtain cellular products and as a substrate for virus reproduction when creating vaccines. Primary and continuous cell lines derived from tumor tissues or normal tissues (bone marrow, kidneys, lungs, skin, connective tissue) are used. To preserve strain properties and prevent genetic mutations, the number of passages (subcultures) is minimized, and cultures are stored in liquid nitrogen.
Typical Production Stages
The technological chain of biotechnological synthesis is strictly standardized and includes five basic steps:
- Producer Selection: choosing the most productive and genetically stable strain.
- Medium Preparation: finding the optimal and cost-effective nutrient base.
- Cultivation: large-scale biomass propagation using industrial equipment.
- Isolation: purification of the target product from the biomass or culture fluid.
- Standardization: formulating the obtained substance into its final medicinal form.