Cytotoxic and antimicrobial activities of phytoconstituents of the stem bark extract of <i>Psychotria djumaensis</i>

Abstract

Phytochemical investigation of the stem bark extract of Psychotria djumaensis led to the isolation of ten known pentacyclic triterpenoids among which one lupane-, three oleanane-,  and six ursane-types. The structures of the isolated compounds were established by means of spectroscopic methods and by comparison with previously reported data. The isolated compounds were tested against five strains of bacteria, and the cytotoxicity against the human cervix carcinoma KB-3-1 cell was evaluated. The isolates exhibited weak antibacterial activity against the five strains. The cytotoxic activity exhibited by 3β,19α-dihydroxyurs-12-en-28-oic acid (5) (IC₅₀ 5.9 µM) was about three times more significant than that of the reference [(+) griseofulvin, IC₅₀ 17-21 µM].