Mean rate of starch breakdown by human and bacterial amylase at five temperatures
Temperature (°C)
Human amylase (mg starch per min)
Bacterial amylase (mg starch per min)
20
1.8
0.6
37
4.6
1.5
50
2.9
3.4
70
0.4
6.2
90
0
2.1
Amylase is an enzyme that hydrolyzes starch into smaller sugars. Researchers compared amylase from human saliva with amylase from a bacterium that lives in hot springs at 70 °C to 80 °C. For each enzyme they mixed the same concentration of enzyme with the same volume of 1% starch solution at pH 7, kept the mixture at one of five temperatures, and measured the rate of starch breakdown. The table shows the mean rate for each condition.