Properties of three purified α-amylases from malted finger millet (Ragi, Eleusine coracana, Indaf-15)

Purified α-amylases from ragi malt (designated as α-1(b), α-2 and α-3), were found to be completely inactivated below pH 4.0 but found to be comparatively more stable in alkaline pH. These iso-enzymes were inactivated around 70 °C. CaCl2 (5–7.5 mM) was enhancing their thermal stability and also found to be an activator. Citric and oxalic acids were inhibiting these enzymes completely between 10 and 12.5 mM concentrations, respectively. EDTA was found to be a competitive inhibitor of these enzymes at micro molar concentrations and inhibition was temperature dependent.