ABSTRACT
The activities of the crude ethanol extract from Piper cubeba seeds, (-)-cubebin and its semi-synthetic derivatives were evaluated against oral pathogens. The crude ethanol extract was more active against Streptococcus salivarius (MIC value of 80 microg/mL). (-)-Cubebin displayed MIC values ranging from 0.20 mm for Streptococcus mitis to 0.35 mm for Enterococcus faecalis. The natural product (-)-cubebin and its semi-synthetic derivative (-)-hinokinin displayed bacteriostatic activity at all evaluated concentrations, as well as fungicidal activity against Candida albicans at 0.28 mm. The O-benzyl cubebin derivative showed fungistatic and fungicidal effects against C. albicans at 0.28 mm and 0.35 mm, respectively. Also, the other dibenzylbutyrolactone derivatives [(-)-6,6'-dinitrohinokinin and (-)-O-(N,N-dimethylaminoethyl)-cubebin] displayed bacteriostatic and fungistatic effects at the evaluated concentrations. Moreover, the semi-synthetic derivative (-)-6,6'-dinitrohinokinin was the most active compound against all the evaluated microorganisms. Therefore, it may be suggested that the presence of the carbonyl group at C-9 plus the introduction of polar groups in the aromatic rings improve the antimicrobial activity of dibenzylbutyrolactone compounds.
Subject(s)
Anti-Infective Agents/pharmacology , Candida albicans/drug effects , Enterococcus faecalis/drug effects , Lignans/pharmacology , Piper/chemistry , Streptococcus/drug effects , 4-Butyrolactone/analogs & derivatives , 4-Butyrolactone/chemistry , 4-Butyrolactone/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/isolation & purification , Benzodioxoles , Dioxoles/chemistry , Dioxoles/pharmacology , Lignans/chemistry , Lignans/isolation & purification , Microbial Sensitivity Tests , Plant Extracts/chemistry , Plant Extracts/pharmacologyABSTRACT
RESUMO Para pesquisa de possíveis vetores envolvidos na transmissão da erliquiose monocítica eqüina (EME) no Rio Grande do Sul, Brasil, caramujos dulciaquícolas dos gêneros Drepanotrema, Physa, Pomacea, Biomphalaria e Heleobia foram coletados em propriedades com histórico de ocorrência de EME localizadas nos Municípios de Rio Grande, Arroio Grande e Santa Vitória do Palmar, extremo sul do Estado. A Neorickettsia (Ehrlichia) risticii foi detectada através de PCR em uma freqüência de 13,33%, em caramujos do gênero Heleobia (H. piscium, H. parchappei e H. davisi). Nesses caramujos, estágios de cercárias e rédias de um trematódeo não identificado foram encontrados. Cercárias emergidas de H. piscium foram classificadas como Parapleurolophocercous cercariae. Esses trematódeos testados por PCR foram positivos para N. risticii em 20% das amostras. Com esses resultados pode-se afirmar que a N. risticii está no ambiente veiculada por caramujos do gênero Heleobia presentes em canais de irrigação e rios da região costeira da Lagoa Mirim, e em trematódeos portados por eles.
ABSTRACT In order to study possible vectors involved in the transmission of Equine monocytic Ehrlichiosis (EME) in Rio Grande do Sul state, Brazil, fresh water snails were collected from establishments with a history of EME occurrence. The snails were collected from the area of Rio Grande, Santa Vitoria and Arroio Grande counties. Snails belonging to the genera Drepanotrema, Physa, Pomacea, Biomphalaria, and Heleobia were found. Neorickettsia (Ehrlichia) risticii were detected in 13.33% of the snails of the genus (Heleobia H. piscium, H. parchappei, H. davisi) using the PCR method, but not in the other genera. In these snails we found cercariae that were classified as Parapleurolophocercous cercariae. It was observed that 20% of the P. cercariae were positive for N. risticii by PCR. Based in our observations we concluded that N. risticii is present in this area of Brazil. Also, we can suggest that its transmission is mediated by the snail of genus Heleobia since this snail harbors the trematode and is present in irrigation channels, rivers and in the coastal area of Mirim Lake.