[Physico-Chemical Properties of Achromobacter SP. α-Amylase]

From Achromobacter sp. 7a, that was isolated with Black sea, aquatoria of island Zmi- inyi, was isolated enzyme with α-amylase activity, that able also to split the synthetic substrates: p-nitrophenyl-α-D-glucopyranoside and p-nitrophenyl-α, -β-D-xylopyranoside. Methods of isolation and purification of enzyme were selected which included: ammonium sulfate precipitation and affinity sorption on starch, that improved enzyme activity in 7 times in comparison with activity in the supernatant of cultural liquid. a-Amylase showed maximal activity at pH 7.0 and 11.0 and to the temperature 50 °C. Enzyme remained fully stable during 24 hours in the range of pH from 7.0 to 12.0, during 3 hours at a temperature 37 °C and 50 °C at pHopt 7.0, and also 87.5 % and 75 % of initial activity saved during 3 h of incubation at a temperature 37 °C and 50 °C at pHopt 11.0 respectively. It is shown that addition of antihunt agents (ions of calcium, chloride of natrium) did not protect an enzyme from thermoinactivation (60 °C, 70 °C).