Olga Lock

Antimicrobial activity of selected Peruvian medicinal plants.

The antimicrobial activity of 36 ethanol extracts from 24 plants, all of them currently used in the Peruvian traditional medicine for the treatment of several infectious and inflammatory disorders, was tested by means of the agar-well diffusion assay against four bacteria (Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa) and four fungi (Candida albicans, Trichophyton mentagrophytes, Microsporum gypseum and Sporothrix schenckii). Twenty-five (69%) extracts showed some degree of antimicrobial activity against at least one microorganism. The plants with the greatest antimicrobial activity were Cestrum auriculatum L. Heritier (Solanaceae), Iryanthera lancifolia Ducke Suesseng (Myristicaceae), Lepechinia meyenii (Walp.) Epling (Lamiaceae) and Ophryosporus peruvianus (Gmelin) King & H. Rob. (Asteraceae).

Structure and estrogenic activity of new lignans from Iryanthera lancifolia

Five new dibenzylbutane type lignans (1-5) were isolated from the stem bark of Iryanthera lancifolia. Their structures were determined by extensive 1D and 2D NMR spectroscopic studies and chemical evidence. Seventeen of the isolated compounds were tested for their estrogenic activities in the estrogen responsive human breast cancer cell line MCF-7 BUS using the E-Screen proliferation assay. Cell proliferation was evaluated by the SRB assay to calculate the estrogenic parameters. The majority of the compounds induced a mitogenic response. This effect, given as Relative Proliferative Effect (RPE) to reference estrogen 17beta-estradiol (E(2)), ranged between 14% and 84%.