BIOTECHNOLOGY - Inshyna N.M. - 2009

CHAPTER 5. INDUSTRIAL BIOTECHNOLOGY

Immobilized Microbial Cells

Methods for the Production of organic acids, Amino acids, Antibiotics, Steroids, and alcohols have been developed using immobilized microbial Cells. Immobilized cells are widely used for wastewater Treatment, as well as for the Processing of agricultural and industrial wastes.

Over 150 years ago, microorganisms adsorbed onto wood sawdust were used for the rapid production of vinegar. The first industrial application of immobilized cells took place in 1974 in Japan for The production of aspartic acid. Japanese scientists currently conduct the world's largest volume of research involving immobilized microbial cells.

At Lomonosov Moscow State University, a method for producing aspartic acid was developed using E. coli cells adsorbed on a polyacrylamide gel. The half-life of this biological catalyst is 110 days.

Compared to immobilized Enzymes, immobilized microbial cells offer several distinct advantages:

1) elimination of costs associated with enzyme Isolation and Purification, alongside reduced expenses for product Separation;

2) high catalytic activity and operational stability;

3) feasibility of establishing continuous automated processes;

4) capability for long-term functioning of multienzyme systems without exogenous Cofactors (living cells regenerate ATP and the Coenzymes NADP⁺, NAD⁺).

Immobilized microbial cells are utilized in a wide range of processes:

- Biosynthesis and biotransformation of Organic compounds (amino acids, organic acids, steroids, Hydrocarbons, NUCLEOTIDES, antibiotics);

- brewing and winemaking;

- purification of wastewater and natural Water sources;

- recovery of metals from wastewater;

- assimilation of solar energy and development of hydrogen solar cells;

- Fixation of Atmospheric nitrogen;

- development of biosensors for analytical research.

A promising direction in biotechnology is the immobilization of PLANT AND ANIMAL cells for the synthesis of physiologically active compounds, as well as the immobilization of cellular Organelles acting as multienzyme systems.