Controlled partitioning of a commercial -amylase is achieved in aqueous biphasic system (ABS) of a hydrophobic and polar ionic liquid, 3-methyl-1-octylimidazol-3-ium saccharinate ([C(8)C(1)im][Sac]). Studying the effects of pH and [C(8)C(1)im][Sac]-concentration, the IL interference in the amylolytic action is deduced. Liquid-liquid extractions into [C(8)C(1)im][Sac] at different pHs are carried out. The -amylase extraction occurs below pH = pI (isoelectric point), and above pI other inactive proteins are preferably transferred. The extracted -amylase is afterwards recovered, being partially purified from inactive protein and microbial pigment. In the ABSs of pHs > pI, the -amylase remains concentrated and purified in the aqueous raffinates.