RESUMO
Escherichia coli is a pathogen associated with infections in piglets in the post-weaning phase, its pathogenicity is related to the animal's susceptibility to bacterial enterotoxins. The objective of the present study was to determine the EOs activity against E. colistrain, in the form planktonic and sessile. Although the Disc-Diffusion tests to determine the Minimum Inhibitory Concentration, do not fully corroborate with the other analyzes of this study, it was noticed bacteria inhibition. The EOs were prepared at 0.4%, 0.8% and 1.0% for tests. The tested EOs were effective against E. coliplanktonic cells (p<0.05). As for the sessile cells, the most significant result was inhibition and 100% sessile cells at the concentration of 1.0% of Cymbopogon citratusEO. Although there was resistance in some treatments, the tested EOs demonstrated inhibition capacity, constituting promising alternatives for the control of E. coli, especially of planktonic cells.
Escherichia coli es un patógeno asociado con infecciones en lechones en la fase posterior al destete, su patogenicidad está relacionada con la susceptibilidad del animal a las enterotoxinas bacterianas. El objetivo del presente estudio fue determinar la actividad de contra E. coli, en la forma planctónico y sésil. Aunque las pruebas de difusión de disco para determinar la concentración inhibitoria mínima, no corroboran completamente con los otros análisis de este estudio, se observó inhibición de la bacteria. Las soluciones basadas en AE se prepararon al 0.4%, 0.8% y 1.0% para pruebas. Los AEs probados fueron efectivos contra las células planctónicas (p<0.05). En cuanto a las células sésiles, el resultado más significativo fue la inhibición y el 100% de las células sésiles a la concentración de 1,0% de Cymbopogon citratus. Aunque hubo resistencia en algunos tratamientos, los AEs probados demostraron capacidad de inhibición, constituyendo alternativas prometedoras para el control de E. coli, especialmente de células planctónicas.
Assuntos
Animais , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Escherichia coli/efeitos dos fármacos , Antibacterianos/farmacologia , Suínos , Óleos Voláteis/química , Extratos Vegetais/química , Testes de Sensibilidade Microbiana , Biofilmes/efeitos dos fármacos , Ocimum basilicum , Cymbopogon , Diarreia/microbiologia , Escherichia coli/isolamento & purificação , Escherichia coli/citologia , Ionização de Chama , Cromatografia Gasosa-Espectrometria de Massas , Antibacterianos/químicaRESUMO
The effect of the crude extract, ethyl acetate and n-butanol fractions from Vitex megapotamica (Spreng) Moldenke on glycemia was investigated in diabetic rats. Oral administration of crude extract significantly reduced serum glucose levels in both normal and diabetic animals. In normal rats, serum glucose lowering was observed with 400 and 800 mg/kg at 2 and 2-3h, respectively after oral crude extract treatment. Nevertheless, the hypoglycemic effect of Vitex megapotamica in diabetic rats was evident at 1 and 2h and from 1 to 3h after treatment with 400 and 800 mg/kg, respectively. The ethyl acetate as well as n-butanol fractions were able to diminish glycemia in diabetic animals. The ethyl acetate fraction (400 and 800 mg/kg) produced the maximum hypoglycemic effect (28 and 20%, respectively) in diabetic rats and the same dose of the n-butanol fraction reduced the hyperglycemia only by 11% at 1h after treatment. Additionally, in hyperglycemic normal rats neither crude extract nor ethyl acetate fraction modified the glucose tolerance and the known tolbutamide effect on insulin release was clearly observed in this group. Thus, this study shows that Vitex megapotamica has an anti-hyperglycemic action, is able to ameliorate the diabetic state and, probably, is a source of hypoglycemic compounds.
Assuntos
Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Hiperglicemia/sangue , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/farmacologia , Fitoterapia , Vitex/química , Acetatos , Animais , Glicemia/metabolismo , Teste de Tolerância a Glucose , Hipoglicemiantes/química , Insulina/farmacologia , Masculino , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Ratos , Ratos Wistar , Solventes , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Tolbutamida/farmacologiaRESUMO
We have investigated the possible antinociceptive action of the extract, fractions and pure compounds obtained from the whole plant Polygala sabulosa A. W. Bennett (Polygalaceae) in acetic acid-induced visceral pain in mice. Intraperitoneal injection of animals with the hydroalcoholic extract and fractions (CH(2)Cl(2), EtOAc, n-BuOH, aqueous fraction) (1-100 mg kg(-1)) caused a dose-related and significant inhibition of the acetic acid-induced visceral nociceptive response. The CH(2)Cl(2), EtOAc and n-BuOH fractions were more potent than the hydroalcoholic extract and aqueous fraction. The isolated compounds dihydrostyryl-2-pyrones (1, 2, 3), styryl-2-pyrone (7), alpha-spinasterol (9), scopoletin (10) and two esters of the coumarin (scopoletin) obtained semisynthetically, acetylscopoletin (10a) and benzoylscopoletin (10b) (0.001-10 mg kg(-1)), exhibited significant and dose-related antinociceptive effects against acetic acid-induced visceral pain. The results distinguished, for the first time, the extract, fractions and pure compounds obtained from P. sabulosa that produced marked antinociception against the acetic acid-induced visceral nociceptive response, supporting the ethnomedical use of P. sabulosa.