por What are bioprocesses?
A bioprocess It is a specific methodology that uses living cells, or other components thereof (enzymes, organelles, among others), to obtain a desired product for the industry or for the benefit of the human being. The bioprocess allows the obtaining of already known products, under optimal environmental conditions, with a higher quality than the traditional way of generating it.
Bioprocesses allow obtaining genetically modified organisms that can be used with the aim of improving the efficiency of specific processes (enzymes or proteins to be used in medical treatments, such as insulin) or consumed directly by humans.
Society and technology can use bioprocesses in different areas to generate better and new techniques. It is applicable to different areas such as food manufacturing, inducing improvements in these, creating medicines, controlling pollution of different types and also controlling global warming.
Currently, the various bioprocesses available to the industry have had a positive impact and millions of investments have been made to promote its growth.
Characteristics of bioprocesses
The most distinctive feature of bioprocesses is the use of live microorganisms or cells to generate specific products. These organisms can be bacteria, fungi, yeast, plant or animal cells, and play an active role in the synthesis or transformation of desirable compounds. Bioprocesses often involve fermentation or cell culture steps. Fermentation is a form of anaerobic metabolism in which microorganisms use organic matter to produce end products, such as ethanol or lactic acid. Cell cultures, on the other hand, are used to produce recombinant proteins, antibodies, and other biotechnological products. Due to the nature of the living organisms involved in bioprocesses, it is crucial to maintain precise control and monitoring of the culture environment. This includes pH, temperature, nutrient concentration, and other factors that affect the growth and production of the organism. Bioprocesses are designed to work on a large scale, which means that they can produce large quantities of products efficiently. The ability to scale production is essential to meet market demand and make the process economically viable. Use of bioreactors and fermentation technology: Bioreactors are essential devices in bioprocesses, as they provide a controlled and sterile environment for the growth and activity of microorganisms. These bioreactors can be of different types, such as stirred tank bioreactors, membrane bioreactors or fixed bed bioreactors, depending on the specific application of the process.
Bioprocess objectives
Biologists and engineers who participate in the development of bioprocesses seek to promote the implementation of this technology, since it allows:
Generate chemicals of significant value. However, the amounts that are generally produced are somewhat small.
The synthesis or modification of products already obtained by the traditional route using the activity of previously isolated microorganisms. These can be amino acids or other organic materials, food, among others.
Transformation of substances in considerable volumes, such as alcohols. These procedures often involve substances with little value.
Through the use of organisms or parts of these, residues and toxic waste can be degraded to transform them into substances that are easy to recycle. These processes are also relevant in the mining industry, with the concentration of metals and the exploitation of virgin mines.
Advantages and disadvantages of the application of bioprocesses
Advantages
Most bioprocesses use enzymes, which are catalysts of a protein nature. These work at a temperature, acidity level and pressure similar to those resisted by living organisms, for this reason the processes occur under «friendly» conditions.
In addition to saving energy, working in human-friendly conditions makes the procedure safer and makes the process easier.
The environmental impact is also reduced, since the products of enzymatic reactions are not toxic waste.
The manufacturing complexes are smaller, simpler and quite flexible, so it is not necessary to make a high capital investment.
Disadvantages
One of the most important is an intrinsic consequence of working with biological systems: susceptibility to contamination. For this reason, work must be carried out under highly controlled aseptic conditions.
In the event that the cultures become contaminated, the microorganisms, the catalysts or the products obtained can be destroyed or lose their functionality, causing considerable losses to the industry.
Another problem is related to the manipulation of labor agencies. Generally, genetics and molecular biology laboratories work with microorganisms on a small scale, where their culture and optimal development is easier. However, extrapolating the process to the mass culture of microorganisms involves a series of obstacles.
Methodologically speaking, the large-scale production of microorganisms is complicated and if it is not carried out correctly it can lead to genetic instability of the system and heterogeneity of the growing organisms.
Types of bioprocesses
The use of microorganisms or other biological entities for the production of substances of interest to humans is very varied. In production, the waste compounds of the microorganism can be isolated to be purified and used.
Similarly, the organism can be modified by applying genetic engineering tools to direct production. This methodology opens up a range of possibilities for the products that can be obtained.
In other cases, it may be the genetically modified organism (and not what can be produced with it) that is of interest.
Stages of a bioprocess
Steps to produce insulin
If working with modified organisms in the laboratory, the first step is the modification. To describe a concrete methodology we will describe the manufacture of a typical recombinant DNA of a product such as insulin, growth hormone or any other common product.
Genetic manipulation
To bring the product to market, the host organism must be genetically manipulated. In this case, the organism is usually Escherichia coli and the cloned DNA will be animal DNA. In this context, «cloned» DNA does not mean that we want to clone an entire organism, it is simply the fragment of the gene of interest.
If we want to produce insulin, we must identify the segment of DNA that has the necessary information for the production of said protein.
After identification, the segment of interest is cut and inserted into the bacterium. E. coli. That is, the bacterium serves as a small production factory, and the researcher gives it the «instructions» by inserting the gene.
This is the stage of genetic engineering, which is carried out on a small scale and by a specialized molecular biologist or biochemist. In this step, basic laboratory equipment is required, such as micropipettes, microcentrifuges, restriction enzymes and an equipment to make electrophoresis gels.
To understand the bioprocess, it is not a requirement to understand all the details involved in cloning, what is important is to understand that the expression levels of the desired product must be optimal and the stability of the product must also be adequate.
Quantify
After the cloning process, the next step is to measure the growth and characteristics of the recombinant cells from the previous step. To do this, you must have skills in microbiology and kinetics.
It must be taken into account that all environmental variables such as temperature, composition of the medium and pH are optimal, to ensure maximum production. In this step, some parameters are quantified, such as cell growth rate, specific productivity and the product.
increase in scale
After the methodology to produce the desired substance has been standardized, the production scale is increased, and 1 or 2 liters of the culture are prepared in a bioreactor.
In this, the conditions of temperature and pH must continue to be maintained. Special attention must be paid to the oxygen concentration required by the culture.
Subsequently, the researchers increasingly increase the scale of production, producing up to 1,000 liters (the amount also depends on the desired product).
Fermentation stages
As we mentioned, bioprocesses are very broad and not all of them involve the steps described in the previous section. For example, fermentation is the concrete and classic example of a bioprocess. Microorganisms such as fungi and bacteria are used in this.
The microorganisms grow in a medium with carbohydrates that they will use for their growth. In this way, the waste product that they produce are those that have industrial value. Among these we have alcohol, lactic acid, among others.
Once the substance of interest is produced by the microorganism, it is concentrated and purified. An endless number of foods (bread, yogurt) and drinks (beer, wine, among others) valuable for human consumption are made using this bioprocess.
Examples of bioprocesses
Beer production. Yogurt production. Production of bioplastics. Recombinant insulin production. Production of industrial enzymes. Production of antibiotics.
References
Cragnolini, A. Questions of scientific and technological policy: materials and sessions of the second Jorge Sabato Ibero-American Seminar on Scientific and Technological Policy. Editorial CSIC-CSIC Press.
Duke, JP Biotechnology. Netbiblo.
Doran, PM Bioprocess engineering principles. Elsevier.
Putting Biotechnology to work: bioprocess engineering. National Academies Press.
Najafpour, G. Biochemical engineering and biotechnology. Elsevier.