The Growth Curve
Fermentation and fermenters -
Is the culturing of microorganisms both anaerobically and aerobically in fermentation tanks. Substance generate by growth of the microorganism culture are separated and treated to produce the wanted product.
Metabolism is a process, metabolites are the products -
Metabolism (sum total of all the chemical reaction in an organism) - Chemical such as hormones and enzymes, waste products such as CO2 and urea.
Primary metabolites - Substances produced by an organism as part of its normal growth; amino acids. The production of these matches the growth in population of the organism.
Secondary metabolites - Substances produced by an organism that are not part of its normal growth; antibiotics. Secondary metabolites begins after the main growth period and does not match the growth in the organisms population.
Commercial Applications of Biotechnology
Industrial-scale fermenters and 'scaling up' -
The growing conditions in the large scale fermenters are manipulated and controlled to ensure best possible yield of desired products. the conditions are determined whether the process wants primary or secondary metabolites:
Temperature - too hot; denature enzymes, too cold; production too slow.
Type and time of addition of nutrient - nutrients required for microorganisms to grow and the time important for production of primary or secondary production.
Oxygen concentration - most need sufficient oxygen levels or anaerobic conditions will produce unwanted substance that can slow growth rate.
pH - changes in pH within the fermenters can reduce the activity of enzymes and reduce growth rates.
Large cultures need started populations of the microorganisms. they are obtained by taking a pure culture and growing it in sterile nutrient broth.