Labdanes and megastigmanes from Vitex negundo var. heterophylla.

ABSTRACT

The aromatic plants of Vitex negundo var. heterophylla are not only herb medicine but also a functional food and an industrial crop. Its leaves can be used as a functional food for improving human's health, but the previous studies mainly focused on the volatile constituents, lignans, and iridoids. Our research led to the isolation of four new terpenoids (1-4), together with fifteen known compounds including seven flavonoids (9-15), two jasmonates (7-8) and six terpenoids (5-6, 16-19) from the leaves. Among all these compounds, 1, 2, 11, and 19 exhibited strong inhibitory activity against NO production in lipopolysaccharide (LPS)-induced RAW264.7 macrophage. The anti-inflammatory mechanism of the most active compound (2) is related to the inhibition of iNOS and COX-2, and the suppression of NF-κB pathway. Therefore, terpenoids and flavonoids from the leaves of Vitex negundo var. heterophylla might be used as potential anti-inflammatory candidates for developing medicine or value-added functional food.