Evaluation of the antimycobacterium activity of the constituents from Ocimum basilicum against Mycobacterium tuberculosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Ocimum basilicum belongs to the genus Ocimum (Lamiaceae). Many species of this genus including O. basilicum have been traditionally used for the treatment of a variety of diseases including respiratory diseases and symptoms of tuberculosis. AIM OF STUDY: The aim of the study was to evaluate the activity of pure constituents of O. basilicum, a plant used in traditional medicine to treat respiratory diseases including symptoms of tuberculosis, against Mycobacterium tuberculosis H37Rv. MATERIALS AND METHODS: The crude methanolic extract from the aerial parts (leaves, fruits and flowers) of the plant was separated into EtOAc and water subextracts and the EtOAc subextract was further divided into acidic and neutral fractions. Each of these was subjected to fractionation through column chromatography followed by prep. TLC. Several pure compounds were thus isolated and their activity was determined against M. tuberculosis H37Rv using MABA assay. RESULTS: Nine compounds were assayed for antituberculosis activity which exhibited upto 49% inhibition of M. tuberculosis H37Rv at 6.25 µg/mL. These include one new compound bacilicin, the structure of which was elucidated based on 2D-NMR (HSQC, HMBC, COSY and NOESY) and Ms spectral analysis. The known compounds were identified on the basis of comparison of their spectral data with those reported earlier. CONCLUSIONS: Inhibition of M. tuberculosis by pure compounds from O. basilicum supports the use of this plant in ethnomedicine as a remedy for symptoms of tuberculosis. The results also suggest that the activity of the plant may be due to a synergistic effect of active compounds including those investigated in the present studies, and hence this plant is a potential candidate for obtaining further new antituberculosis natural products.

Chemical constituents of Cordia latifolia and their nematicidal activity.

Following nematicidal activity-guided isolation studies on the fruits, bark, and leaves of Cordia latifolia, two new constituents, cordinoic acid (=11-oxours-12-ene-23,28-dioic acid; 1) and cordicilin (=2-{[(E)-3-(3,4-dihydroxyphenyl)prop-2-enoyl]oxy}-3-[4-hydroxy-3-(stearoyloxy)phenyl]propanoic acid; 2) were isolated from the stem and leaves, respectively, together with nine known compounds, namely cordioic and cordifolic acid from the stem bark, latifolicin A-D and rosmarinic acid from the fruits, and cordinol and cordicinol from the leaves. Their structures were determined by means of spectroscopic analyses including 1D- and 2D-NMR techniques. The nematicidal activities of these constituents were determined against the root-knot nematode Meloidogyne incognita. Hundred percent mortality was caused by all of these after 72 h at a 0.125% concentration. Compound 1 and cordioic acid were most active and caused 100% mortality after 24 h at a 0.50% concentration. Furthermore, compound 2, the ester of rosemarinic acid, was found to be more active than the free acid.

Three new constituents, latifolinal, latifolidin and cordicinol, from the fruits and leaves of Cordia latifolia.

Isolation and structure elucidation of three new natural constituents are reported. These include a new substituted furfuryl ester of stearic acid, latifolinal (1), and two aromatic compounds, latifolidin (2) and cordicinol (3). Compounds 1 and 2 were obtained from the dried fruits and compound 3 from the leaves of Cordia latifolia.

Steroidal constituents from the aerial parts of Lippia nodiflora Linn.

The methanolic extract of the aerial parts of Lippia nodiflora Linn. afforded one new and two known steroids. The structure of the new steroid had been elucidated as 4',5'-dimethoxybenzoloxystigmasterol (1) by an analysis of the spectral data, including extensive NMR experiments and its chemical transformation to stigmasterol. The known steroids were identified as stigmasterol and beta-sitosterol through comparison of their spectral data with those reported in the literature.

Preparation, structure and spasmolytic activities of some derivatives of harmine series of alkaloids.

Keeping in view the interesting chemistry and pharmacological importance of harmine series of bases -- the beta-carboline alkaloids, a number of new derivatives of tetrahydroharmine and harmalol have been prepared and characterized through spectral studies. Some of these derivatives showed spasmolytic activity. It was observed that all the N-acyl tetrahydroharmine derivatives are stable, not labile and no ring opening occurs in these compounds, as reported recently.

Studies on the chemical constituents of the fruits of Cordia latifolia.

Four new aromatic compounds have been isolated from the fruits of Cordia latifolia (Boreginaceae) bearing a common basic skeleton but differing in the side chain. Their structures were elucidated using spectrometric methods including 1D- (1H and 13C) and 2D-NMR experiments, (1H, 1H-COSY, NOESY, HMQC and HMBC) and chemical transformations.