title: Phytochemical prospection and modulation of antibiotic activity in vitro by Lippia origanoides H.B.K. in methicillin resistant Staphylococcus aureus.
abstract: The Lippia origanoides H.B.K. ethanol extract (LOEE) and hexane (LOHEX), dichloromethane (LODCM), and ethyl acetate (LOEA) fractions were tested for their antimicrobial activity alone or in combination with antibiotics against a methicillin resistant Staphylococcus aureus (MRSA) strain. The natural products did not show antimicrobial activity against multidrug resistant strain at the clinically significant concentrations tested. However, a modulatory effect in the antibacterial activity of the neomycin and amikacin was verified when LOEE, LOHEX and LODCM were added to the growth medium at subinhibitory concentrations. A similar modulation was found when the natural products were changed for chlorpromazine, an inhibitor of bacterial efflux pumps, suggesting the involvement of resistance mediated by efflux system in the MRSA tested. The fractions LOHEX and LODCM showed a modulatory activity bigger than their majority compounds (carvacrol, thymol, and naringenin), indicating that this activity is not due to their majority compounds only, but it is probably due to a synergism between their chemical components. These results indicate that L. origanoides H.B.K. can be a source of phytochemicals able to modify the phenotype of resistance to aminoglycosides in MRSA.
authors.affiliation: Laboratory of Microbiology and Immunology, Campus Amílcar Ferreira Sobral, Universidade Federal do Piauí, BR 343, Km 3,5 Bairro Meladão, 64800-000 Floriano, PI, Brazil.
authors.forename: Humberto
authors.initials: H
authors.lastname: Medeiros Barreto
authors.affiliation: Laboratory of Microbiology and Immunology, Campus Amílcar Ferreira Sobral, Universidade Federal do Piauí, BR 343, Km 3,5 Bairro Meladão, 64800-000 Floriano, PI, Brazil.
authors.forename: Filipe
authors.initials: F
authors.lastname: Cerqueira Fontinele
authors.affiliation: Center for Research on Medicinal Plants, Universidade Federal do Piauí, Bairro Ininga, 64049-550 Teresina, PI, Brazil.
authors.forename: Aldeídia
authors.initials: A
authors.lastname: Pereira de Oliveira
authors.affiliation: Center for Research on Medicinal Plants, Universidade Federal do Piauí, Bairro Ininga, 64049-550 Teresina, PI, Brazil.
authors.forename: Daniel Dias Rufino
authors.initials: DD
authors.lastname: Arcanjo
authors.affiliation: Laboratory of Clinical Microbiology, Universidade Federal da Paraiba, Cidade Universitária, 58051-900 João Pessoa, PB, Brazil.
authors.forename: Bernadete Helena
authors.initials: BH
authors.lastname: Cavalcanti Dos Santos
authors.affiliation: Laboratory of Microbiology, Faculdade de Ensino Superior de Floriano, Bairro Manguinha, 64800-000 Floriano, PI, Brazil.
authors.forename: Aislan Pereira Lira
authors.initials: AP
authors.lastname: de Abreu
authors.affiliation: Laboratory of Microbiology and Molecular Biology, Regional University of Cariri, Bairro Pimenta, 63105-100 Crato, CE, Brazil.
authors.forename: Henrique
authors.initials: H
authors.lastname: Douglas Melo Coutinho
authors.affiliation: Laboratory of Natural Products, Universidade Federal do Piauí, Bairro Ininga, 64049-550 Teresina, PI, Brazil.
authors.forename: Romezio
authors.initials: R
authors.lastname: Alves Carvalho da Silva
authors.affiliation: Laboratory of Natural Products, Universidade Federal do Piauí, Bairro Ininga, 64049-550 Teresina, PI, Brazil.
authors.forename: Taciana
authors.initials: T
authors.lastname: Oliveira de Sousa
authors.affiliation: Laboratory of Natural Products, Universidade Federal do Piauí, Bairro Ininga, 64049-550 Teresina, PI, Brazil.
authors.forename: Maria das Graças
authors.initials: Md
authors.lastname: Freire de Medeiros
authors.affiliation: Laboratory of Natural Products, Universidade Federal do Piauí, Bairro Ininga, 64049-550 Teresina, PI, Brazil.
authors.forename: Antonia Maria das Graças
authors.initials: AM
authors.lastname: Lopes Citó
authors.affiliation: Laboratory of Natural Products, Universidade Federal do Piauí, Bairro Ininga, 64049-550 Teresina, PI, Brazil.
authors.forename: José Arimateia
authors.initials: JA
authors.lastname: Dantas Lopes
mesh_terms: D000085:Acetates / Q000737:chemistry; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002746:Chlorpromazine / Q000494:pharmacology; D000081007:Cymenes; D000431:Ethanol / Q000737:chemistry; D044950:Flavanones / Q000494:pharmacology; D008401:Gas Chromatography-Mass Spectrometry; D006586:Hexanes / Q000737:chemistry; D032411:Lippia / Q000737:chemistry*; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects*; D008752:Methylene Chloride / Q000737:chemistry; D008826:Microbial Sensitivity Tests; D039821:Monoterpenes / Q000494:pharmacology; D064209:Phytochemicals / Q000494:pharmacology*; D010936:Plant Extracts / Q000494:pharmacology; D013943:Thymol / Q000494:pharmacology
chemical_list: D000085:Acetates; D000900:Anti-Bacterial Agents; D000081007:Cymenes; D044950:Flavanones; D006586:Hexanes; D039821:Monoterpenes; D064209:Phytochemicals; D010936:Plant Extracts; C026385:n-hexane; D013943:Thymol; D000431:Ethanol; D008752:Methylene Chloride; C007650:ethyl acetate; C073316:carvacrol; C005273:naringenin; D002746:Chlorpromazine