EFFECTS OF POLAR ORGANIC-SOLVENTS ON THE BIOCATALYSIS OF CHLOROPHYLLASE IN A BIPHASIC ORGANIC-SYSTEM

The effects of polarity of various organic solvents, including acetone, ethanol, and propanol, used in a biphasic organic system, on the hydrolytic activity of a partially purified chlorophyllase from Phaeodactylum tricornutum were investigated. The different concentrations of each polar organic solvent, from 0 to 40%, were added to a mixture (45:55, v/v) of hexane and a buffer solution of Tris-HCl (20 mM, pH 7.5). The most appropriate concentrations of acetone, ethanol, and propanol for the hydrolytic activity of chlorophyllase were 12.5, 5.0, and 2.5%, respectively. The results indicated that the optimum reaction time for the chlorophyllase activity in the biphasic system decreased from 7.0 h to 3.0, 5.0, and 5.0 h, respectively, upon the addition of an appropriate amount of acetone, ethanol, or propanol. The V-max and K-m as well as the inhibitory effect of phytol on the chlorophyllase activity in the biphasic organic system containing a polar organic solvent were also investigated.