Typically, cell cultures and raw materials (called “broth”) are mixed by an agitator and then allowed to settle. As the broth settles, the fermentation process begins and the cells start to grow. CO² gases, produced by the fermentation process, are drawn through filters by a vacuum pump in the top of the fermentation vessel. The filters keep outside contaminants from getting into the vessel, and prevent the microorganisms from getting out.
The University of Bergen, the highest ranking University in Norway, is carrying out tests to survey the mercury exposure levels in dental offices in Tanzania, where amalgam fillings are still used in dentistry.