LIPASE INHIBITORS IN CASSIA-MIMOSOIDES L- VAR NOMAME MAKINO

The crude extract from Cassia mimosoides L. var. nomame Makino signifi cantly inhibited lipase activity. In this paper, lipase inhibitors in the above plant were studied. The lipase activity was assayed in a hom ogeneous mixture of water and organic solvents with lipase B-detergent complexes soluble in organic solvents. A component that inhibited the activity was purified and identified as pheophorbide a. The effects o f various chlorophyll derivatives and related substances on the lipase activity in various reaction mixtures were also studied. Substances c ontaining a porphyrin ring inhibited the activity in the mixture of wa ter and organic solvents and in water when porcine pancreas lipase and 4-methylumbelliferyl oleate were used. The metal complex of chlorophy llin strongly inhibited the activity in water alone. The effects of pr oteins on the inhibition caused by chlorophyllin were examined by comp arison with epigallocatechin gallate (EgCg), an inhibitor that is phen olic. The inhibition caused by chlorophyllin was so decreased less tha n the inhibition caused by the phenolic inhibitor when casein was pres ent. Chlorophyllin activated the lipase activity when bovine serum alb umin was present, but the phenolic inhibitor did not have this effect. These results suggest that the mechanism of the inhibition by chlorop hyllin is different from that of the phenolic inhibitor.