Isolation of Arginase Inhibitors from the Bioactivity-Guided Fractionation of Byrsonima coccolobifolia Leaves and Stems

摘要

Byrsoninia coccolobifolia leaf and stem extracts were studied in the search for possible leishmanicidal compounds using arginase (ARG) from Leishmania amazonensis as a molecular target. Flavonoids 1b, 1e-1g, 2a, 2b, and 2d-2f showed significant inhibitory activity, with 1050 values ranging from 09 to 4.8 mu M. The kinetics of the most active compounds were determined. Flavonoids 1e, 1f, 2a, 2b, and 2e were characterized as noncompetitive inhibitors of ARG with dissociation constants (K-i) ranging from 0.24 to 3.8 mu M, demonstrating strong affinity. Structure-activity relationship studies revealed some similarities in the structural features of flavonoids related to ARG activity.