Antimicrobial activity of various parts of Polyalthia longifolia var. pendula: isolation of active principles from the leaves and the berries.

Methanol extracts of leaves, stem, twigs, green berries, flowers, roots, root-wood and root-bark of Polyalthia longifolia var. pendula, were tested for their antibacterial and antifungal potentials. Bioassay monitored isolation work on the methanol extract of leaves and berries which possess promising antibacterial activity led to the isolation of seven clerodane diterpenoids, 16(R and S)-hydroxy-cleroda-3,13(14)Z-dien-15,16-olide (1), 16-oxo-cleroda-3,13(14)E-dien-15-oic acid (2), methyl-16-oxo-cleroda-3,13(14)E-dien-15-oate (3), 2-oxo-kolavenic acid (4), 16 (R and S)-hydroxy-cleroda-3,13(14)Z-dien-15,16-olide-2-one (5), (4-->2)-abeo-16(R and S)-hydroxy-cleroda-2,13(14)Z-dien-15,16-olide-3-al (6), 3beta,16alpha-dihydroxy-cleroda-4(18), 13(14)Z-dien-15,16-olide (7), while kolavenic acid (8) and solidagonal acid (9) were obtained from the root-wood.