Resultado da pesquisa (2)

Termo utilizado na pesquisa plant extract

#1 - Antimicrobial activity of plant extracts and compounds over resistant Gram-negative isolates from domestic animals

Abstract in English:

Gram-negative bacteria present significant challenges due to their antimicrobial resistance. Members of the Enterobacterales order, such as Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis, pose the greatest risk to public health because of their numerous mechanisms of antimicrobial resistance. Therefore, this study aimed to evaluate the antimicrobial activity of crude ethanolic extracts (CEE) of Hymenaea martiana Hayne (jatobá), Commiphora leptophloeos (Mart.) Gillett (imburana), Ocimum campechianum Mill. (alfalvaca) and Morus nigra L. (amora miura), as well as the hexane and ethyl acetate fractions of the last one, against clinical isolates of Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis obtained from domestic animals. Furthermore, three commercially available compounds – gallic acid (GA), p-Coumaric acid (p-CA), benzoic acid (BA) – and one conducting polymer (synthesized for the test), polypyrrole (Ppy), were also evaluated for their antimicrobial potential against these isolates. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts and compounds were determined. All E. coli and K. pneumoniae isolates were resistant to the tested extracts. The crude ethanolic extracts showed inhibitory activity against P. mirabilis isolates at concentrations of 3,125 µg/mL for H. martiana and 12,500 µg/mL for O. campechianum. However, C. leptophloeos, M. nigra, and their fractions (hexane and ethyl acetate), as well as GA, did not exhibit bactericidal activity against any of the pathogens. Benzoic acid demonstrated both inhibitory and bactericidal activity against all isolates, with pronounced bactericidal activity against two K. pneumoniae isolates (MBC of 2,000 µg/mL). p-Coumaric acid showed inhibitory activity against all isolates and bactericidal activity (MBC of 5,000 µg/mL) against 66.66% (4/6) of the isolates, proving effective against E. coli and K. pneumoniae. Polypyrrole exhibited the most potent antibacterial activity, inhibiting 100% of the isolates and showing bactericidal activity against 83.33% (5/6) of the clinical isolates tested. These results suggest that the tested extracts and compounds, particularly polypyrrole, may offer a viable alternative against multidrug-resistant microorganisms.

Abstract in Portuguese:

Gram-negative bacteria present significant challenges due to their antimicrobial resistance. Members of the Enterobacterales order, such as Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis, pose the greatest risk to public health because of their numerous mechanisms of antimicrobial resistance. Therefore, this study aimed to evaluate the antimicrobial activity of crude ethanolic extracts (CEE) of Hymenaea martiana Hayne (jatobá), Commiphora leptophloeos (Mart.) Gillett (imburana), Ocimum campechianum Mill. (alfalvaca) and Morus nigra L. (amora miura), as well as the hexane and ethyl acetate fractions of the last one, against clinical isolates of Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis obtained from domestic animals. Furthermore, three commercially available compounds – gallic acid (GA), p-Coumaric acid (p-CA), benzoic acid (BA) – and one conducting polymer (synthesized for the test), polypyrrole (Ppy), were also evaluated for their antimicrobial potential against these isolates. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts and compounds were determined. All E. coli and K. pneumoniae isolates were resistant to the tested extracts. The crude ethanolic extracts showed inhibitory activity against P. mirabilis isolates at concentrations of 3,125 µg/mL for H. martiana and 12,500 µg/mL for O. campechianum. However, C. leptophloeos, M. nigra, and their fractions (hexane and ethyl acetate), as well as GA, did not exhibit bactericidal activity against any of the pathogens. Benzoic acid demonstrated both inhibitory and bactericidal activity against all isolates, with pronounced bactericidal activity against two K. pneumoniae isolates (MBC of 2,000 µg/mL). p-Coumaric acid showed inhibitory activity against all isolates and bactericidal activity (MBC of 5,000 µg/mL) against 66.66% (4/6) of the isolates, proving effective against E. coli and K. pneumoniae. Polypyrrole exhibited the most potent antibacterial activity, inhibiting 100% of the isolates and showing bactericidal activity against 83.33% (5/6) of the clinical isolates tested. These results suggest that the tested extracts and compounds, particularly polypyrrole, may offer a viable alternative against multidrug-resistant microorganisms.


#2 - Efficacy of a Kalanchoe gastonis-bonnieri extract to control bacterial biofilms and dental calculus in dogs, 37(8):859-865

Abstract in English:

ABSTRACT.- Abdalla S.L., Costa S.S., Gioso M.A., Casanova L.M., Coutinho M.A.S., Silva M.F.A., Botelho M.C.S.N. & Dias R.S.G. 2017. Efficacy of a Kalanchoe gastonis-bonnieri extract to control bacterial biofilms and dental calculus in dogs. Pesquisa Veterinária Brasileira 37(8):859-865. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Avenida Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitária, São Paulo, SP 05508-270, Brazil. E-mail: pgcir@usp.br An aqueous leaf extract of the medicinal species Kalanchoe gastonis-bonnieri (here denominated KGB) has been found to be effective as an antimicrobial agent against canine oral cavity bacteria in in vitro assays. In this study, we investigated the effect of topic oral administration of KGB on the development of dental biofilm in Beagle dogs. The experiments were performed with an experimental group (0.2% of KGB extract), a negative control group (0.9% of saline solution) and a positive control group (0.12% chlorhexidine). Each treatment was sprayed into the oral cavity daily for 28 days. Thirty Beagle dogs with similar characteristics and kept under the same management and diet were used. The measurement of dental plaque and calculus was performed using a computerized analytical method. The phenolic profile of KGB extract was analyzed by HPLC-DAD. KGB extract at 0.2% showed efficacy in controlling the formation of plaque compared to the negative control group, and dental calculus in relation to the negative and positive control groups. A significant difference was observed among these three groups. Peaks attributed to flavonoids and phenolic acids were identified in the HPLC-DAD chromatogram of the KGB extract. The presence of these substances could be related to the activity observed. Our findings demonstrate that treatment with KGB is effective in controlling periodontal disease in dogs, providing new insights into the medicinal properties of this plant. KGB extract has a potential use as a supplemental agent in pharmaceutical products for the prevention of periodontal disease.

Abstract in Portuguese:

RESUMO.- Abdalla S.L., Costa S.S., Gioso M.A., Casanova L.M., Coutinho M.A.S., Silva M.F.A., Botelho M.C.S.N. & Dias R.S.G. 2017. Efficacy of a Kalanchoe gastonis-bonnieri extract to control bacterial biofilms and dental calculus in dogs. [Eficácia do extrato de Kalanchoe gastonis-bonnieri no controle do biofilme bacteriano e cálculo dentário em cães.] Pesquisa Veterinária Brasileira 37(8):859-865. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Avenida Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitária, São Paulo, SP 05508-270, Brazil. E-mail: pgcir@usp.br Um extrato aquoso de folhas da espécie medicinal Kalanchoe gastonis-bonnieri (aqui denominado como KGB) foi efetivo como um agente antimicrobiano contra as bactérias da cavidade oral de cães em testes in vitro. Neste estudo, investigou-se o efeito da administração oral tópica de KGB sobre o desenvolvimento do biofilme dental em cães da raça Beagle. Os experimentos foram realizados com um grupo experimental (0,2% de extrato de KGB), um grupo controle negativo (0,9% de solução salina) e um grupo controle positivo (0,12% de gluconato de clorexidina). Cada tratamento foi aplicado no interior da cavidade oral diariamente durante 28 dias. Foram utilizados trinta cães da raça Beagle com características semelhantes e mantidos sob o mesmo manejo e dieta. A medição da placa bacteriana e cálculo dentários foi realizada utilizando-se um método de análise computadorizada. O perfil fenólico do extrato de KGB foi analisado por HPLC-DAD. O extrato de KGB a 0,2% mostrou eficácia no controle da formação de placa bacteriana em comparação com o grupo controle negativo, e de cálculo dentário em relação aos grupos controle negativo e positivo. Uma diferença significativa foi observada entre esses três grupos. Picos atribuídos a flavonoides e ácidos fenólicos foram identificados no cromatograma de HPLC-DAD do extrato de KGB. A presença de tais substâncias pode estar relacionada com a atividade observada. Os resultados demonstram que o tratamento com KGB é eficaz no controle da doença periodontal em cães, fornecendo novas perspectivas sobre as propriedades medicinais desta planta. O extrato de KGB tem uma utilização potencial como um agente suplementar em produtos farmacêuticos para a prevenção da doença periodontal.


Colégio Brasileiro de Patologia Animal SciELO Brasil CAPES CNPQ UFRRJ CFMV