ÿþ<HTML><HEAD><TITLE>XI International Meeting on Paracoccidioidomycosis</TITLE><link rel=STYLESHEET type=text/css href=css.css></HEAD><BODY aLink=#ff0000 bgColor=#FFFFFF leftMargin=0 link=#000000 text=#000000 topMargin=0 vLink=#000000 marginheight=0 marginwidth=0><table align=center width=700 cellpadding=0 cellspacing=0><tr><td align=left bgcolor=#cccccc valign=top width=550><font face=arial size=2><strong><font face=Verdana, Arial, Helvetica, sans-serif size=3><font size=1>XI International Meeting on Paracoccidioidomycosis</font></font></strong><font face=Verdana size=1><b><br></b></font><font face=Verdana, Arial,Helvetica, sans-serif size=1><strong> </strong></font></font></td><td align=right bgcolor=#cccccc valign=top width=150><font face=arial size=2><strong><font face=Verdana, Arial, Helvetica, sans-serif size=1><font size=1>Resume:84-2</font></em></font></strong></font></td></tr><tr><td colspan=2><br><br><table align=center width=700><tr><td><b>Poster (Painel)</b><br><table width="100%"><tr><td width="60">84-2</td><td><b>Antifungal activity of compounds isolated from Baccharis dracunculifolia against Paracoccidioides brasiliensis</b></td></tr><tr><td valign=top>Authors:</td><td>Flavia Beraldo Oliveira (FIOCRUZ - Fundação Oswaldo Cruz) ; <u>Susana Johann </u> (UFMG - Universidade Federal de Minas GeraisFIOCRUZ - Fundação Oswaldo Cruz) ; Betania Barros Cota (FIOCRUZ - Fundação Oswaldo Cruz) ; Carlos Augusto Rosa (UFMG - Universidade Federal de Minas Gerais) ; Ezequias Pessoa Siqueira (FIOCRUZ - Fundação Oswaldo Cruz) ; Patricia Silva Cisalpino (UFMG - Universidade Federal de Minas Gerais) ; Carlos Leomar Zani (FIOCRUZ - Fundação Oswaldo Cruz) </td></tr></table><p align=justify><b><font size=2>Abstract</font></b><p align=justify class=tres><font size=2><i>Baccharis dracunculifolia</i>, popularly known as "alecrim do campo , belongs to the family Asteraceae, that contains about 23 000 species and is native of South America. The extract of this plant is used in folk medicine as an antiseptic, anti-inflammatory and to treat gastric and skin ulcers. Scientific research disclosed several biological activities such as: anti-plasmodial, anti-ulcerative and cytocidal. This study aimed to look for chemical constituents in the hexane fraction of aerial parts from <i>B. dracunculifolia</i>. The hexane fraction and the subfractions were tested on microdilution assay in order to obtain the MIC values against <i>P. brasiliensis</i>. The isolated compounds were tested in the presence of ergosterol and sorbitol to evaluate its putative effects in membrane and cell wall of the pathogenic fungus. The present phytochemical study led to the isolation of four substances: ursolic acid (1), caryophyllene oxide (2), trans-nerolidol (3) and methyl linolenate (4). The substances 2, 3 and 4 showed activity against <i>P. brasiliensis</i> in concentrations ranging from 125 to 250 &#956;g/ml, 15.6 to 125 &#956;g/ml and 3.9 to 31.2 &#956;g/ml, respectively. It was observed, that the culture medium (RPMI and YPD broth) modulates the phenotypic profile of the isolates of <i>P. brasiliensis</i> (Pb 18, Pb 01, Pb 608 and Pb B339) tested. In this test only the substance 2, showed a difference in MIC with the medium supplemented with ergosterol, suggesting that this substance may be acting in fungal ergosterol biosynthesis. we found that none of the substances tested showed changes in MIC on presence the sorbitol. These findings suggest that the compounds isolated in present work not act through the inhibition of cell wall synthesis or assembly in <i>P. brasiliensis</i>. The activity of the substances 2, 3 and 4 against <i>P. brasiliensis</i> was first reported in this study</font></p><br><b>Keyword: </b>&nbsp;Antifungal, Baccharis dracunculifolia, Ergosterol, Paracoccidioides brasiliensis</td></tr></table></tr></td></table></body></html>