Effect of pentacyclic guanidine alkaloids on activity of natural 1,3β-D-glucanases from marine hydrobionts

Abstract

The effect of pentacyclic guanidine alkaloids monanchomycalin B, monanchocidin A and normonanchocidin
A isolated from the marine sponge Monanchora pulchra was investigated towards the activity of exo-1,3-β-D-glucanase from the filamentous marine fungus Chaetomium indicum and endo-1,3-β-Dglucanase LIV from the marine bivalve mollusk Pseudocardium(Spisula) sachalinensis. All compounds were shown to be slow irreversible inhibitors of exo-1,3-β-D-glucanase and significantly activated endo-
1,3-β-D-glucanase. The inhibitory capacities of alkaloids were shown to depend on the structure of the
“anchor” part of the molecule of the compounds. Normonanchocidin A was the best inhibitor of exo-1,3-
β-D-glucanase from fungus.