Bioengineering, is a new comprehensive and applied discipline that began to emerge in the early 1970s.
The so-called bioengineering is generally considered to be based on the theory and technology of biology (especially microbiology, genetics, biochemistry and cytology), combined with modern engineering technologies such as chemical, mechanical, electronic computer, etc., and fully utilizing the latest achievements of molecular biology to consciously manipulate the genetic material and directionally modify the organisms or their functions, and to create new species with super-teleological traits in short term. The new species, and then through the appropriate bioreactor of such "engineering bacteria" or "engineering cell lines" for large-scale culture, in order to produce a large number of useful metabolites or play their unique physiological functions of an emerging technology.
Bioengineering includes five major projects, namely, genetic engineering (genetic engineering), cell engineering, microbial engineering (fermentation engineering), enzyme engineering (biochemical engineering) and bioreactor engineering. Of these five major fields, the first two act to use conventional bacteria (or plant and animal cell lines) as recipients of specific genetic material, so that they acquire foreign genes and become new species capable of expressing super-distant traits - "engineered bacteria" or "engineered cell lines". The role of the latter three is to create favorable conditions for the growth and propagation of this new species of great potential value, and to carry out large-scale cultivation in order to give full play to its intrinsic potential and provide people with great economic and social benefits.
Bioengineering has a wide range of applications, including agriculture, industry, medicine, pharmacology, energy, environmental protection, metallurgy, chemical raw materials and so on. It is bound to have a great impact on the political, economic, military and life of human society, and provide a bright prospect for the solution of the problems of resources, environment and human health faced by the world.
Fermentation Engineering
(1) "Fermentation" has the meaning of "fermentation strictly defined by microbial physiology" and "industrial fermentation". The word "fermentation" in "fermentation engineering" should be "industrial fermentation".
(2) In industrial production, products are processed or made by "industrial fermentation", and the corresponding processing or making process is called "fermentation process". In order to realize industrial production, it is necessary to solve the problem of industrial production environment, equipment and process control engineering to realize these processes (fermentation process), therefore, there is "fermentation engineering".
(3) Fermentation engineering is a discipline used to solve the engineering problems of industrial production by fermentation process. Fermentation engineering from the engineering point of view to realize the fermentation process of fermentation industrial process is divided into strains, fermentation and refining (including wastewater treatment) and other three stages, these three stages have their own engineering problems, generally referred to as fermentation engineering upstream, midstream and downstream engineering.
(4) Microorganisms are the soul of fermentation engineering. In recent years, the understanding of the biological properties of fermentation engineering has become clearer and clearer, and fermentation engineering is approaching science.
(5) The most basic principle of fermentation engineering is the biological principle of fermentation engineering.
(6) Fermentation engineering has three stages of development.
Fermentation engineering in the modern sense is a multidisciplinary cross, fusion and the formation of a strong technical and applied open discipline. Fermentation engineering has gone through three stages of development, namely, "manual processing of agricultural products - modern fermentation engineering - modern fermentation engineering".
Fermentation engineering originated from the family or workshop fermentation production (agricultural manual processing), then borrowed from the chemical engineering to achieve industrial production (modern fermentation engineering), and finally returned to the truth to microbial life activities as the center of the research, design and guidance of industrial fermentation production (modern fermentation engineering), crossing the ranks of bioengineering.
The original handmade fermentation production by virtue of the skills and experience passed down from ancestors to produce fermented products, physical labor is heavy, the production scale is limited, it is difficult to achieve industrialized production. Therefore, the fermentation industry's predecessors first turned to chemistry and chemical engineering to learn from agricultural chemistry and chemical engineering, standardized the fermentation production process, used pumps and pipelines and other transport methods to replace the shoulder and hand-carrying manpower handling, machine production instead of manual operation, and successfully pushed the workshop-type fermentation production up to the level of industrialized production. The combination of fermentation production with chemistry and chemical engineering led to the first leap in fermentation production.
Through the decades of practice of industrialized fermentation production, people gradually realized that the fermentation process is a time-varying (time-varying), non-linear, multivariate input and output of the dynamic biological process, according to the chemical engineering model to deal with the fermentation industrial production (especially large-scale production), it is often difficult to receive the expected results. From the chemical engineering point of view, the fermenter is also the production of raw materials fermentation reactor, the fermenter culture of microbial cells is only a catalyst, according to the orthodox thinking of chemical engineering, microorganisms of course, it is difficult to play its life-specific production potential. Thus, tracing back to the biological kernel (microorganisms) of the workshop-type fermentation production technology, a new understanding of the properties of fermentation engineering has been achieved by going back to the basics. The identification of the biological properties of fermentation engineering, so that the development of fermentation engineering has a clear direction, fermentation engineering into the category of biological engineering.
Fermentation engineering refers to the use of engineering technology means, the use of living organisms (mainly microorganisms) and active isolated enzyme certain functions, for human production of useful biological products, or directly with microorganisms involved in the control of certain industrial production process of a technology. People are familiar with the use of yeast fermentation manufacturing beer, fruit wine, industrial alcohol, lactic acid bacteria fermentation manufacturing cheese and sour milk, the use of fungi mass production of penicillin and so on are examples of this. With the progress of science and technology, fermentation technology has also developed greatly, and has entered the stage of modern fermentation engineering that can artificially control and transform microorganisms to make these microorganisms produce products for human beings. As an important part of modern biotechnology, modern fermentation engineering has broad application prospects. For example, genetic engineering methods to purposefully modify the original strain and improve its yield; the use of microbial fermentation to produce drugs, such as human insulin, interferon and growth hormone.
Already from the past simple production of alcoholic beverages, the production of acetic acid and fermented bread to today's development of an extremely important branch of bioengineering, a multidisciplinary project that includes microbiology, chemical engineering, genetic engineering, cellular engineering, mechanical engineering and computer hardware and software engineering. Modern fermentation engineering not only produces alcoholic beverages, acetic acid and bread, but also produces insulin, interferon, growth hormone, antibiotics and vaccines and other health care drugs, the production of natural pesticides, bacterial fertilizers and microbial herbicides and other agricultural means of production, the production of amino acids in the chemical industry, fragrances, biomacromolecules, enzymes, vitamins and single-cell proteins.
In a broad sense, fermentation engineering consists of three parts: it is upstream engineering, midstream engineering and downstream engineering. Among them, the upstream engineering includes the selection and breeding of excellent breeding strains, the determination of optimal fermentation conditions (pH, temperature, dissolved oxygen and nutrient composition), and the preparation of nutrients. The midstream engineering mainly refers to the process technology for mass cultivation of cells and production of metabolites in fermenters under optimal fermentation conditions. Here there is a strict aseptic growth environment, including the technology of sterilizing the fermentation raw materials and the fermenter as well as various connecting pipelines using high temperature and high pressure before the start of the fermentation; the air filtration technology that continuously passes dry and sterile air into the fermenter during the fermentation process; the computer-controlled technology that controls the dosing rate according to the requirements of the cell growth in the process of the fermentation; as well as the different process technologies for the seed cultivation and the production of the cultivated products. In addition, according to different needs, the fermentation process is also categorized as batch fermentation: i.e., one-pitch fermentation; flow-added batch fermentation: i.e., based on one-pitch fermentation, flow-added a certain amount of nutrients, so as to make the cells grow further or get more metabolites; and continuous fermentation: continuously flow-added nutrients, and continuously take out the fermentation broth. Before any large-scale industrial fermentation is carried out, a large number of experiments must be carried out in small laboratory-scale fermenters to obtain a kinetic model of product formation, and to design the fermentation requirements for a pilot plant based on this model, and finally to design a kinetic model for larger-scale production from the pilot data. Due to the complexity of the biological reaction, many problems arise during the process from laboratory to pilot, and from pilot to large-scale production, which is the problem of fermentation engineering process scale-up. Downstream engineering refers to the technology of separating and purifying products from the fermentation broth: including solid-liquid separation technology (centrifugation, filtration, precipitation, etc.), cell-breaking technology (ultrasound, high-pressure shear, osmotic pressure, surfactants, and lysophospholipases, etc.), protein purification technology (sedimentation, chromatography, and ultrafiltration, etc.), and finally, packaging and processing of the products (vacuum drying and freeze-drying, etc.).
In addition, in the fermentation industry for the production of drugs and food, it is necessary to strictly comply with the cGMPs published by the U.S. Federal Food and Drug Administration, and to regularly accept the inspection and supervision of the relevant authorities.