biochemical engineering

biochemical engineering

Biochemical engineering

The application of engineering principles to conceive, design, develop, operate, or use processes and products based on biological and biochemical phenomena. Biochemical engineering, a subset of chemical engineering, impacts a broad range of industries, including health care, agriculture, food, enzymes, chemicals, waste treatment, and energy. Historically, biochemical engineering has been distinguished from biomedical engineering by its emphasis on biochemistry and microbiology and by the lack of a health care focus. However, now there is increasing participation of biochemical engineers in the direct development of health care products. Biochemical engineering has been central to the development of the biotechnology industry, especially with the need to generate prospective products (often using genetically engineered microorganisms) on scales sufficient for testing, regulatory evaluation, and subsequent sale. See Biotechnology

In the discipline's initial stages, biochemical engineers were chiefly concerned with optimizing the growth of microorganisms under aerobic conditions at scales of up to thousands of liters. While the scope of the discipline has expanded, this focus remains. Often the aim is the development of an economical process to maximize biomass production (and hence a particular chemical, biochemical, or protein), taking into consideration raw-material and other operating costs. The elemental constituents of biomass (carbon, nitrogen, oxygen, hydrogen, and to a lesser extent phosphorus, sulfur, mineral salts, and trace amounts of certain metals) are added to the biological reactor (often called a fermentor) and consumed by the bacteria as they reproduce and carry out metabolic processes. Sufficient amounts of oxygen (usually supplied as sterile air) are added to the fermentor in such a way as to promote its availability to the growing culture. See Chemical reactor

In some situations, microorganisms may be cultivated whose activity is adversely affected by the presence of dissolved oxygen. Anaerobic cultures are typical of fermentations in which organic acids and solvents are produced; these systems are usually characterized by slower growth rates and lower biomass yields. The largest application of anaerobic microorganisms is in waste treatment, where anaerobic digesters containing mixed communities of anaerobic microorganisms are used to reduce the quantity of solids in industrial and municipal wastes.

While the operation and optimization of large-scale, aerobic cultures of microorganisms is still of major importance in biochemical engineering, the capability of cultivating a wide range of cell types has become important also. Biochemical engineers are often involved in the culture of plant cells, insect cells, and mammalian cells, as well as the genetically engineered versions of these cell types. Metabolic engineering uses the tools of molecular genetics, often coupled with quantitative models of metabolic pathways and bioreactor operation, to optimize cellular function for the production of specific metabolites and proteins. Enzyme engineering focuses on the identification, design, and use of biocatalysts for the production of useful chemicals and biochemicals. Tissue engineering involves material, biochemical, and medical aspects related to the transplant of living cells to treat diseases. Biochemical engineers are also actively involved in many aspects of bioremediation, immunotechnology, vaccine development, and the use of cells and enzymes capable of functioning in extreme environments.