ABSTRACT
Fourteen extracts from Brazilian traditional medicinal plants used to treat infectious diseases were used to look for potential antimicrobial activity against multiresistant bacteria of medical importance. Staphylococcus aureus strains were susceptible to extracts of Punica granatum and Tabebuia avellanedae. The minimum inhibitory concentrations (MICs) of the total extracts and of additional fractions of these plants were determined by employing strains of methicillin-resistant (MRSA) and -sensitive (MSSA) S. aureus, including isolates of the PFGE clone A, which is prevalent in Brazil and two ATCC reference strains. A mixture of ellagitannins isolated from P. granatum and two naphthoquinones isolated from T. avellanedae demonstrated antibacterial activity against all S. aureus strains tested. Semi-synthetic furanonaphthoquinones (FNQs) showed lower MICs than those exhibited by natural occurring naphthoquinones. The results indicate that these natural products can be effective potential candidates for the development of new strategies to treat MRSA infections.
Subject(s)
Hydrolyzable Tannins , Naphthoquinones/pharmacology , Plants, Medicinal , Staphylococcus aureus/drug effects , Brazil , Humans , In Vitro Techniques , Lythraceae , Methicillin Resistance , Microbial Sensitivity Tests , Naphthoquinones/administration & dosage , Naphthoquinones/chemistry , Naphthoquinones/isolation & purification , Phytotherapy , Plant Extracts/administration & dosage , Plant Extracts/pharmacology , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Staphylococcus aureus/isolation & purification , Tabebuia , Tannins/administration & dosage , Tannins/chemistry , Tannins/isolation & purification , Tannins/pharmacologyABSTRACT
São analisadas as características microscópicas entre os caules de Lippia alba e de Melissa officinalis, ambas conhecidas no Brasil como "ervas cidreiras" e consumidas pela população em virtude de suas propriedades sedativas e antiespasmódicas. A análise dos cortes transversais dos seus caules, que geralmente aparecem misturados às folhas das duas espécies em estudo, auxilia a diagnose da matéria prima vegetal.
The microscopic characteristics of the stems of Lippia alba and Melissa officinalis, both known in Brazil as "erva cidreira" and consumed by the population in virtue of their sedative and antispasmodic properties, were analyzed. Analysis of the transverse section these stems, which often appear mixed with the leaves of the two species, help in the differentiation of the raw plant material.
