Study of the in vitro antimicrobial activity of harmine, harmaline and their derivatives

Peganum harmala L. (Zygophyllaceae), commonly known as harmal, grows wild in the semiarid regions of IndoPakistan subcontinent, Iran and Africa. Its different parts have been used in traditional systems of medicine for the treatment of a variety of human ailments (Dymock et al., 1890; Chopra et al, 1956). Peganum harmala is known to contain four main alkaloids, namely harmaline (Ci3Hi40N2) reported by Goebel, harmine (Ci3H120N2) isolated by Fritsche, harmalol (Ci2Hi20NZ) noted by Goebel and prepared by Fischer from harmaline, and peganine (C,,Hi20Nz) obtained by Merk and later found to be identical with vasicine isolated earlier by Hooper (Henry, 1949). Harmal alkaloids have been reported to possess hypotensive activity (Codding, 1983), while earlier the seeds have been shown to have a marked physiological activity (Elger, 1928) and have been used for curative purposes (El-Saad and EI-Rifaie, 1980). Preliminary work on the antimicrobial study of the crude ethanolic extract of seeds of Peganum harmala was perfomed by different groups of workers (Ross et al., 1980; Al-Sharma and co-