Beta galactosidase activity is influenced by pH and temperature in different ways, depending on where the molecule is being isolated from. Beta-galactosidase derived fromBacillus circulanshas an optimal pH of 6 and an optimal temperature of 50 °C. Beta galactosidases derived from Drosophilahave an optimal pH of either 6 or 7. Another example is beta glucosidases isolated from Aspergillus nigerhave an optimal pHbetween 3-5 and temperature between 55–60°C. 

Alterations in pH and temperature affect beta galactosidase activity when outside the optimal ranges and can reduce activity. For example, in beta glucosidases isolated from Aspergillus niger,low acid environments can denature the enzyme.