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As in vitro plant cultures are used extensively to produce bioactive metabolites, our goal was to establish calli from Tulbaghia violacea Harv. flowers and assess the tissue phytochemically and biologically. Murashige & Skoog medium(MS) + 22.6 μM 2,4-dichlorophenoxyacetic acid +2.2 μM benzylaminopurine induced callus from flowers. Gas chromatography/mass spectrometry(GC/MS) analyses of n-hexane extracts of calli(HC) and flowers(HF) revealed 33 and 32 components(92.6 and 98.5%, respectively). Hydrocarbons were predominant in HC (55.0%), whereas a higher percentage of oxygenated compounds was found in HF(74.6%). Trans(E)-anethole(39.1%) and 16-hentriacontanone (30.3%) dominated in HF and HC, respectively. However, sulphur compounds were only detected in HF. Quantitative estimation of thiosulphinates, phenolics, flavonoids and saponins in ethanolic extracts of calli(EC) and flowers(EF) showed much higher contents in EF. Antioxidant, antimicrobial and cytotoxic screening of extracts demonstrated that EF was the most potent, followed by HF and EC; conversely, HC was inactive. Although HC and EC were less biologically active, these calli could be an alternative source of bioactive metabolites.

Objective: Development of a rapid isolation method to afford the bioactive metabolite (proximadiol: prox) from its herb (Cymbopogan proximus Stapf.) in the purest form and validate an LC method for its determination was our goal in this work. Methods:Prox was isolated by chromatographic techniques from the dichloromethane extract of the herb on alumina column, using petroleum ether-ethyl acetate solvent mixtures with increasing polarity.The determination of prox was achieved by LC method. The chromatographic separation was carried out on Thermo Hypersil ODS (4.5 x 250 mm, 10 µm) column, in the presence of 8-chlorotheophylline as an internal standard. The mobile phase was composed of 0.1 M phosphate buffer (pH: 3.5): methanol (60:40 v/v) and was pumped at a flow rate of 1 ml/min. The detection and quantification were done at 210 nm. Results:The structure elucidation of the isolated compound was identified on the basis of its spectral data.A simple and reproducible LC method was developed for the determination of the isolated purified Prox. Adequate separation and good resolution were obtained between prox and 8-chlorotheophylline. Quantification was achieved at 210 nm over concentration range 12.00-33.60 µg/ml with mean percentage recovery of 99.29±0.340. The method was validated in accordance with USP specifications. All analytical criterions were within acceptable range. The validity of the results was assessed by applying standard addition technique. The results obtained were compared with the reported method. Conclusion:The proposed method could be applied for routine quality control analysis of pharmaceutical formulations containing prox.