RESUMO

Due to the great biodiversity of its flora, Brazil provides combat tools against bacterial resistance with the utilization of natural products with vegetable origin. Therefore, the present study had as its objective to evaluate the antibacterial potential of the Eugenia uniflora essential oil (EuEO) in vitro, as well as to analyze the modulatory effect of the oil against antibiotics by gaseous contact and to compare them when associated with a LED apparatus. The chemical components were characterised by gas chromatography which revealed the presence of the isoflurane-germacrene, considered the major component (61.69%). The MIC obtained from the EuEO was ≥256 µg/mL for S. aureus and ≥1024 µg/mL for E. coli. When combined with antibiotics, the EuEO presented synergism reducing the MIC when associated, with the exception of gentamicin against E. coli, where an antagonistic effect was observed. The was an interference of the EuEO over the activity of ciprofloxacin when associated with red and blue LED lights, increasing the inhibition halos against S. aureus and E. coli. Norfloxacin presented similar results to ciprofloxacin against S. aureus bacteria. When combined, norfloxacin and the EuEO presented synergism against S. aureus, which did not occur in the combination with ciprofloxacin. Interference occurred only with blue light for E. coli. Thus, it was observed that the EuEO causes changes in the activity of antibiotics, the same occurring with the use of LED lights, without significant differences in the association of the oil and the lights with the antibiotics tested. Further research is needed to elucidate the modulatory effects of the EuEO, as well as its association with LED lights.

Assuntos

RESUMO

Bacterial resistance has risen as an important health problem with impact on the pharmaceutical industry because many antibiotics have become ineffective, which has affected their commercialization. The Brazilian biodiversity is marked by a vast variety of natural products with significant therapeutic potential, which could bring new perspectives in the treatment of infections caused by resistant microorganisms. The present study aimed to evaluate the antibacterial effect of the essential oil obtained from Eugenia jambolana (EjEO) using the method of microdilution method to determine the Minimum Inhibitory Concentration (MIC). The modulatory effect of this oil on antibiotic activity was determined using both the broth microdilution and gaseous contact methods. The antibacterial effect of the association of the gaseous contact and the use of a LED unit with red and blue lights was also determined. The chemical components of the EjEO were characterized by HPLC, which revealed the presence of α-pinene as a major constituent. The EjEO presented a MIC≥128µg/mL against S. aureus and ≥1024µg/mL against E. coli. The combination of the EjEO with antibiotics presented synergism against E. coli and antagonism against S. aureus. An antagonistic effect was obtained from the association of EjEO with amikacin and erythromycin by the method of gaseous contact. On the other hand, the association of EjEO with ciprofloxacin presented a synergistic effect against S. aureus and E. coli exposed to LED lights. A similar effect was observed in the association of the EjEO with norfloxacin presented synergism against S. aureus in the same conditions. In conclusion, our results demonstrated that the essential oil obtained from Eugenia jambolana interfere with the action of antibiotics against bacteria exposed to LED lights. Thus, further researches are required to elucidate the mechanisms underlying these effects, which could open new perspectives in the development of new antibacterial therapies.

Assuntos

RESUMO

Sideroxylon obtusifolium, conhecida como quixaba, é utilizada para diversos fins medicinais, dentre eles em casos de inflamações e infecções bacterianas, com isso, o estudo teve por objetivo investigar a atividade anti-inflamatória tópica e antibacteriana do extrato metanólico obtido das folhas de S. obtusifolium. A prospecção fitoquímica do extrato revelou a presença de diversas classes, entre eles: Fenóis; Taninos Pirogálicos, Flavonoides, Catequinas e alcaloides. Os polifenóis e flavonóides presentes neste extrato foram quantificados em 150,3 mg equivalentes de ácido gálico/g de extrato e 98,5 mg equivalentes de quercetina/g de extrato, respectivamente. Os resultados obtidos através dos testes de microdiluição e modulação mostraram potencial atividade antibacteriana quando associados a gentamicina e amicacina para cepas multirresistentes de Staphylococcus aureus. Para cepas de Escherichia coli, houve sinergismo frente ao antibiótico amicacina havendo antagonismo para gentamicina, o mesmo efeito foi observado para Pseudomonas aeruginosas em ambos antibióticos. Nos testes para inflamação aguda através dos modelos de edema de orelha induzido por óleo de cróton e fenol, o extrato apresentou um potente efeito antiedematogênico significativo (p < 0,05). Diante dos resultados, podem-se observar atividades biológicas de S. obtusifolium, o que condiz com seu uso na terapia popular.

Sideroxylon obtusifolium, known as "quixaba", is used for various medicinal purposes, including in cases of inflammation and bacterial infections, therefore, the study aimed to investigate the topical antibacterial and anti-inflammatory activity of the methanol extract obtained from the leaves of S. obtusifolium. The phytochemical screening of the extract revealed the presence of several classes, including Phenols; Tannins, Flavonoids, catechins and alkaloids. Polyphenols and flavonoids present in this extract were quantified in 150.3 mg of gallic acid equivalents / g extract and 98.5 mg of quercetin equivalents / g extract, respectively. The results obtained by the microdilution tests have shown potential and modulation antibacterial activity when associated gentamicin, and amikacin for multidrug-resistant strains of Staphylococcus aureus. For Escherichia coli, there was synergism for amikacin, gentamicin having antagonism, the same effect was observed for Pseudomonas aeruginosa on both antibiotics. In tests for acute models of inflammation by ear edema induced by croton oil, and phenol, the extract had a potent antiedematogenic significant effect (p < 0.05). Therefore, the results can be observed biological activities of S. obtusifolium, which is consistent with its use in popular therapy.

Sideroxylon obtusifolium conocida como quixaba, se utiliza para diversos fines medicinales, incluso en los casos de infecciones bacterianas y la inflamación, por lo tanto, este estudio tuvo como objetivo investigar la actividad antiinflamatoria tópica y antibacteriana del extracto de metanol obtenido de las hojas de S. obtusifolium. El tamizaje fitoquímico del extracto reveló la presencia de varias clases, incluyendo: fenoles; taninos pirogálicos, flavonoides, catequinas y alcaloides. Los polifenoles y flavonoides presentes en este extracto se cuantificaron en 150,3 mg de equivalentes de ácido/g de extracto gálico y 98,5 mg de extracto de quercetina equivalentes/g, respectivamente. Los resultados obtenidos por los ensayos de microdilución han mostrado actividad potencial y la modulación antibacteriana cuando se asocia gentamicina, amikacina y para las cepas resistentes a múltiples fármacos de Staphylococcus aureus. Para Escherichia coli, solo se obtuvo sinergismo con amikacina, y se observo antagonismo para gentamicina, este mismo efecto fue observado para Pseudomonas aeruginosa en ambos antibióticos. En las pruebas de modelos agudos de inflamación por edema de la oreja inducido por aceite de crotón, y el fenol, el extracto tuvo un efecto significativo antiedematogenic potente (p <0,05). Por lo tanto, los resultados muestran actividad biológica de S. obtusifolium, que es coherente con su uso en terapia popular.