ABSTRACT
Poincianella pyramidalis (Tul.) LP Queiroz (Fabaceae) is an endemic tree of northeastern Brazil, occurring mainly in the Caatinga. Its medicinal use is widespread and is an important therapeutic option against diarrhea, dysentery, and respiratory and urinary infections, among other diseases. In this study we determined the chemical marker and evaluated the interaction between P. pyramidalis extract and a commercial antimicrobial through the use of biological and analytical models. To obtain the extract, an ethanol-water mixture (50:50 v/v) was used as solvent. It was nebulized in a spray dryer using colloidal silicon dioxide as a drying adjuvant. The extract (ENPp) was subjected to HPLC analysis to verify the presence of certain secondary metabolites. The Minimum Inhibitory Concentration (MIC) of the extract against Gram-negative bacteria was determined by broth microdilution and the MIC of synthetic antimicrobial drugs in the presence and absence of the extract. The antioxidant activity of ENPp was evaluated by the DPPH method. The compatibility between the antimicrobial and the extract was evaluated by thermal analysis (TG/DTA). The acute toxicity of the extract was evaluated in vivo in rodents. The results indicate significant additive action of the extract on synthetic antibiotics, considerable antioxidant activity and absence of toxicity. This extract shows high potential for the development of formulations for antimicrobial therapy when used with a vegetable-active ingredient.
Subject(s)
Anti-Infective Agents/pharmacology , Caesalpinia/chemistry , Plant Extracts/pharmacology , Animals , Antioxidants/chemistry , Antioxidants/pharmacology , Bacteria/drug effects , Chromatography , Drug Interactions , Female , Flavonoids/chemistry , Flavonoids/pharmacology , Male , Microbial Sensitivity Tests , Phytochemicals/chemistry , Phytochemicals/pharmacology , Plant Extracts/chemistry , Polyphenols/chemistry , Polyphenols/pharmacology , Rats , Thermodynamics , Thermogravimetry , Toxicity Tests, AcuteABSTRACT
It was evaluated the in vitro efficacy of ethanolic extract of leaves and bark of Ximenia americana L and Schinopsis brasiliensis Engl. alone and in association with erythromycin as modulators of microbial resistance against six clinical isolates of Staphylococcus aureus resistant to erythromycin (SA1-SA6) and S. aureus ATCC 25923 by the microdilution method. The extracts were also subjected to bioassay with Artemia salina. The ethanolic extract of barks of X. americana showed a synergistic effect with erythromycin against SA01, SA03 and SA04. The leaf extract of S. brasiliensis exerted synergistic effect against SA03 and the bark extract showed against SA01 and S03. The results suggest that extracts from S.brasiliensis and X. americana have potential as modulator agents of bacterial resistance, which could be used as adjuvants in the treatment of infections by S. aureus resistant to erythromycin, with previous studies of toxicity.
Se evaluó la eficacia in vitro de los extractos etanólicos de hojas y corteza de Ximenia americana L y Schinopsis brasiliensis Engl solos y en asociación con eritromicina como moduladores de la resistencia microbiana frente a seis aislados clínicos de Staphylococcus aureus resistentes a Eritromicina (SA1-SA6) y S. aureus ATCC 25923, por el método de microdilución. Además se determinó la actividad tóxica de los extractos contra Artemia salina. Solo el extracto etanólico de la corteza de X. americana mostró un efecto sinérgico con la eritromicina frente a SA01, SA03 y SA04. El extracto de las hojas de S. brasiliensis ejerció efecto sinérgico contra SA03 y el extracto de corteza, contra SA01 y S03. Los resultados sugieren que S. brasiliensis y X. americana tienen potencial como agentes moduladores de la resistencia bacteriana, que podrían ser utilizados como adyuvantes en el tratamiento de infecciones por S. aureus resistentes a eritromicina, con estudios previos de toxicidad.