Abstract
(-)-Epicatechin-3-gallate (ECG) and (-)-epigallocatechin-3-gallate (EGCG), major tea catechins, formed precipitates with soybean lipoxygenase (LOX) in the pH range of 4-7, although with accompanying 10-30%loss of the LOXactivity. Yeast alcohol dehydrogenase also was precipitated by EGCG. Polyvinylpyrrolidone, Tween 20 and Triton X-100 dissociated the LOX activity from the EGCG-precipitated LOX. However, the MWof the dissociated LOX(1 14, 000) differed from that of the native LOX(100, 000). Enzymeactivities of the EGCG-precipitated LOX and the dissociated LOXfrom the precipitate were less stable than the activity of the native LOX. These findings suggest the altered natures of proteins in the presence of tea catechins, ECG and EGCG.
