ABSTRACT
Sabe-se que a transmissão de infecções hospitalares, via cruzada ou ambiental, é facilitada pela sobrevivência de microrganismos em superfícies secas que pode ser favorecida pela presença de fluídos biológicos. Visando demonstrar o cuidado com substâncias corporais narotina de limpeza, esse estudo avaliou a influência de alguns fluídos biológicos (sangue, urina e saliva artificial) na sobrevivência de Staphylococcus aureus (ATCC 25923), depositados de modo similar, sobre diferentes superfícies após secagem. O sangue foi capaz de preservar a viabilidade bacteriana por até 72 diasquando depositado sobre piso cerâmico. O tecido em fibra de algodão permitiu maior tempo de sobrevivência em comparação ao tecido sintético. Esses resultados demonstram que a composição do fluído biológico e o tipo de suporte altera o tempo da sobrevivência bacteriana em condições ambientais.
Subject(s)
Cross Infection , Bacterial Infections/transmission , Staphylococcus aureusABSTRACT
The first isocoumarin isolated from the methylene chloride extract of Paepalanthus bromelioides, named paepalantine (isocoumarin 1), was found to have antimicrobial activity; but, it is mutagenic clastogenic and cytotoxic. Two other isocoumarins, paepalantine-9-O-beta-D-glucopyranoside (isocoumarin 2) and paepalantine-9-O-beta-D-allopyranosyl(1 --> 6) glucopyranoside (isocoumarin 3) were isolated from the ethanolic extract. A fourth new isocoumarin, also isolated from the methylene chloride extract of the capitula of P. bromelioides, was characterized as an 8-8' dimer of paepalantine and denominated isocoumarin 4. The abilities of isocoumarins 2, 3 and 4 to induce mutations in Salmonella typhimurium strains TA97a, TA98, TA100 and TA102 were investigated. Mutagenic activity was observed in strain TA97a treated with isocoumarin 2 in the presence of S9 mixture. The substitution of H at position 9 by glucose or glucose-allose caused reductions in the mutagenic activities of paepalantine, indicating this to be an important site for these properties.
Subject(s)
Coumarins/adverse effects , Eriocaulaceae , Glycosides/adverse effects , Mutagens/isolation & purification , Animals , Coumarins/chemistry , Coumarins/isolation & purification , Cricetinae , Dimerization , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical , Glycosides/chemistry , Glycosides/isolation & purification , Isocoumarins , Methylene Chloride/chemistry , Mutagenicity Tests , Mutagens/adverse effects , Mutagens/chemistry , Plant Extracts/adverse effects , Plant Extracts/chemistry , Plants, Medicinal/chemistry , Salmonella typhimurium/drug effects , Salmonella typhimurium/genetics , Species Specificity , Spindle Apparatus/drug effects , Structure-Activity RelationshipABSTRACT
A new naphthopyrone dimer was isolated from the capitula of Paepalanthus bromelioides by chromatographic procedures. It structure was deduced from spectrometric data. On colorimetric assay for cytotoxicity the new dimer showed IC50 of 55.9 microM.
