Selma Ribeiro de Paiva

Antimicrobial activity in vitro of plumbagin isolated from Plumbago species

Plumbagin is a naturally occurring naphthoquinone isolated from roots of Plumbago scandens. The plant was collected at the Campus of Fundação Oswaldo Cruz, Rio de Janeiro, Brazil. P. scandens is used as a traditional medicine for the treatment of several diseases. The antimicrobial activity of plumbagin was evaluated using the macrodilution method. The compound exhibited relatively specific activity against bacteria and yeast. The minimum inhibitory concentration test showed the growth inhibiton of Staphylococcus aureus at a concentration of 1.56 g/ml and of Candida albicans at a concentration of 0.78 g/ml. These results suggest the naphthoquinone plumbagin as a promising antimicrobial agent.

Plumbagin quantification in roots of Plumbago scandens L. obtained by different extraction techniques

The Plumbago genus belongs to the Plumbaginaceae family and it is known due to its variety of biological uses, most of them attributed to the presence of naphthoquinones. Plumbagin is a naturally occurring naphthoquinone that can be obtained from roots of Plumbago scandens L. In order to find out the better technique for plumbagin extraction, were applied: static maceration, dynamic maceration, with assistance of ultrasonic waves and in Soxhlet apparatus. Four compounds were qualitatively detected in all extracts: the naphthoquinones plumbagin and epi-isoshinanolone, palmitic acid and sitosterol. Plumbagin was always the major component in all analyzed extracts and it was quantitatively determined by gas chromatograph coupled with mass spectrometer. Soxhlet was the most efficient extraction technique however, prolonged heating time promoted plumbagin degradation.

Ecology and variability of chemical mediators from Plumbago species

SUMMARY OF COMMUNICATIONS STORMSURGEMODELINGANDFORECASTFORTHESOUTH-WESTERN ATLANTIC OCEAN RicardodeCamargo 1 ,JosephHarari 2 andPedroL.S.Dias 11 Department of Atmospheric Sciences, Institute of Astronomyand Geophysics of University of Sao Paulo. 2 Department of Physical Oceanography, Institute of Oceanogra-phy of University of Sao Paulo.Presented by IgorG.Pacca StormsurgesovertheAtlanticCoastofSouthAmer-ica have important effects in terms of coastal erosion,sediment dynamics and harbor activities, among manyothers. The aim of this project is to present a numeri-cal system for storm surge forecasts in the South-WesternAtlantic Ocean, basically from the northern Argentineanshelf (42 ◦ S) to the Rio de Janeiro coast (21 ◦ S), hereaftercalled SWAO region. The idealized system would be ableto provide disturbances in the surface elevation and shelfcurrents fields related to the passage of meteorologicalsystems over the studied area. It is very important to men-tion the cyclogenetic characteristics of the region of inter-est, which play an important role for storm surge events.Mesoscale meteorological forecasts for the studyarea can be supplied by operational runs of the RegionalAtmospheric Modelling Systems (RAMS) at the Depart-mentofAtmosphericSciencesofUniversityofSaoPaulo.The model assimilates large scale analysed and predictedfields provided by global models (normally NCEP andCPTEC, and occasionally ECMWF) and improves theforecast considering regional aspects in a 32km grid.The oceanic part of the proposed system is basedon the Princeton Ocean Model (POM) simulations for theSWAO area with approximately 10km resolution, whichwillbeforcedbypredictedwindfieldsprovidedbyRAMSas described above. The use of mesoscale wind fields inprevious hindcasting simulations shown better results incomparison to wind fields directly from global models.—( November 19, 1999 ).