Types Of Bioprocesses

Gaden classified fermentation processes into three types. In type 1 process the production is due to result of primary metabolism. The rate of product formation is directly related to the rate of substrate consumption and also to the rate of cell mass produced. Examples of aerobic systems that follow this classification are acetic acid (using Gluconobacter suboxidans), single-cell protein (using Candida utilis, S. cerevisiae) and baker's yeast (using S. cerevisiae). The first system is operated...

Gas Dispersion In Stirred Bioreactors

The purpose of agitation is to create gas holdup by producing small bubbles that, however, because of a low free rise velocity escape slowly from the liquid. Consequently the area available for mass transfer should increase however, the mass transfer coefficient does not change much. In fact, it may show a decrease for very fine bubbles that behave like rigid solid particles. The gas holdup in a stirred vessel is controlled by the energy input and gas sparging rate. At low speeds of agitation...

Chiral Drugs And Intermediates

Chiral drugs business in 2001 reached 100 billion, representing one-third of all drugs sales worldwide. The industry's continuing growth is partly because of the discoveries in fundamental biochemistry. Of the top 100 drugs marketed today, 50 are single isomers. Single isomer drugs sale reached 115 billion worldwide in 1999 (32 of the total drug market) and expected to reach 146 billion in 2003. All this activity on chiral drugs has led the fine chemical producers to develop new...

Types Of Reactors

The biochemical reactors can be broadly classified into submerged and surface reactors 2,6 . In surface reactors the culture adheres to a solid surface and oxygen is supplied from the gas phase to the continuously wetted solid surface. Wastewater treatment employs such designs. In submerged reactors gas-to-liquid mass transfer is achieved by dispersing the gas in the liquid through continuous input of energy. Submerged reactors can be divided into three groups depending upon the nature of the...