Bioassay-guided fractionation of an organic extract of the cell mass from a manipulated plant cell culture of Mirabilis jalapa led to the isolation and subsequent identification of three new phenolic compounds, 1, 2, and 3. The isoflavone 1 and dehydrorotenoid 2 were identified as the principal antifungal principles from this plant cell culture with IC(50)'s of 25 and 48 microg/mL, respectively, against the test organism, Candida albicans DSY1024. The rotenoid 3 was inactive at 200 microg/mL in this assay.

of incubation at 37C, the medium was discarded and replaced with 100 L of DMSO.The OD 570 was determined with a microplate reader (CLARIO Star Microplate reader, BMG Labtech, UK) and each experiment was repeated three times with five replicates in each experiment. The OD 570 obtained for the controls cells (no extract) was arbitrarily set at 100% and the OD 570 value for cells treated with extracts were expressed as a percentage of this control. The IC 50 values were calculated using

This method is precise, less time consuming and more cost effective, and can be used for the quality control of any G. glabra sample with regard to its glycyrrhizin contents.

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Ceil suspension cultures of the Madagascan Periwinkle Catharanthus roseus (L) G. Don were maintained on Gamborg's B5 medium and their growth monitored by measuring cellular fresh and dry weight, ceil number and mitotic activity. Samples of cells of different ages and physiological states were subcultured onto an alkaloid production medium and their rates of growth and alkaloid accumulation measured over a period of 30-45 days. In two experiments the rate of biomass accumulation was directly related to the rate of cellular serpentine accumulation. Possible mechanisms underlying this phenomenon are discussed in relation to the properties of cells comprising the inocula.