A group of researchers isolated the amylase enzyme form Pseudoalteromonas arctica, a marine bacterium indigenous to the waters of the Arctic Ocean surrounding the Norwegian island, Spitzbergen. In the November 2010 issue of "The Protein Journal," the researchers stated that the optimal temperature of the enzyme was 30 degrees Celsius and the activity of the molecule was reduced by 65 percent at zero degrees Celsius. Additionally, the study reported that the enzymatic activity decreased sharply at temperatures above 40 degrees Celsius.
The freshwater zooplankton, Heliodiaptomus viduus, contains a large amount of amylase: 2,400 molecules for each gram of body weight. A study published in the March 2006 issue of "The Turkish Journal of Zoology" reported that the enzyme had maximum activity between 30.25 and 70.25 degrees Celsius at a pH of 6.0. The study further reported that full enzymatic activity occurred at 30 degrees Celsius for up to two hours. Additionally, the enzyme became inactive at 60.25 degrees Celsius after two hours and at 70.25 degrees Celsius after one hour.
The January 1989 issue of "Biotechnology and Bioengineering" reported that the α-amylase enzyme isolated from the bacterium, Bacillus iicheniformis, was active over a broad range of temperatures. The researchers adjusted the temperature of a medium containing the bacterium incrementally from 4 to 22 to 37 and finally to 80 degrees Celsius. They found that the enzymatic activity increased along with temperature, until the enzyme denatured at 80 degrees Celsius.
An article published in the July 2009 issue of "Biotechnology Progress" investigated the potential use of the amylase enzyme, isolated from the bacterium, Bacillus subtilis, as an indicator of pressure, temperature and time for a pasteurization process. The researchers found that the amylase enzymatic activity was uninhibited at temperatures ranging from 10 to 50 degrees Celsius, but decreased at each temperature as pressure and time increased.