title: Rauvolfia grandiflora (apocynaceae) extract interferes with staphylococcal density, enterotoxin production and antimicrobial activity.
abstract: Staphylococci bacteria are involved in many human and animal infections and development of alternative antimicrobial drugs against pathogenic bacteria is of great interest to the pharmaceutical industry. This study investigated the in vitro effect of Rauvolfia grandiflora methanol extract (root bark fraction) (RGE) on the density of ATCC strains of Staphylococcus aureus and Staphylococcus epidermidis, and a clinical enterotoxin-producer, S. aureus bovine strain. The alkaloid, isoreserpiline, obtained from dichloromethane extract of R. grandiflora was ineffective against the strains tested. After incubation of staphylococci strains in the presence of 1.2 μg.mL(-1) RGE, a significant inhibition of cell growth was observed using both spectrophotometry and ELISA assays. Twelve drugs were evaluated for their antimicrobial effects on culture RGE-treated cells using the disk diffusion method. Penicillin resistant strains became sensitive to the drug after RGE treatment. Furthermore, enterotoxin production by RGE-treated S. aureus was evaluated using a standardized ELISA method. Although staphylococcal LSA 88 bovine strain cells remained viable after exposure to the extract, enterotoxin production was precluded in 20% after RGE treatment. Significant interference in staphylococci cell density, drug sensitivity and enterotoxin secretion was observed after treatment. The study highlights the necessity to find new methods of disease prevention and new antibiotic therapies against staphylococcal infections.
authors.affiliation: Laboratório de Zootecnia e Nutrição Animal, Universidade Estadual do Norte Fluminense , Campos dos Goytacazes, RJ , Brasil ; Laboratório de Tecnologia de Alimentos, Universidade Estadual do Norte Fluminense , Campos dos Goytacazes, RJ , Brasil.
authors.forename: Lanamar
authors.initials: L
authors.lastname: de Almeida Carlos
authors.forename: Kenas Aguiar
authors.initials: KA
authors.lastname: da Silva Amaral
authors.forename: Ivo José
authors.initials: IJ
authors.lastname: Curcino Vieira
authors.forename: Leda
authors.initials: L
authors.lastname: Mathias
authors.forename: Raimundo
authors.initials: R
authors.lastname: Braz-Filho
authors.forename: Solange
authors.initials: S
authors.lastname: Silva Samarão
authors.forename: Olney
authors.initials: O
authors.lastname: Vieira-da-Motta
keywords: Rauvolfia grandiflora; Staphylococcus aureus; antimicrobial activity.; enterotoxin
references.citation: Mol Microbiol. 2003 Jun;48(6):1429-49
references.pmid: 12791129
references.citation: Proc Natl Acad Sci U S A. 1995 Feb 28;92(5):1619-23
references.pmid: 7533297
references.citation: Mol Pharmacol. 2008 May;73(5):1578-86
references.pmid: 18314496
references.citation: Infect Immun. 2000 Sep;68(9):5385-92
references.pmid: 10948168
references.citation: Vet Microbiol. 1993 Apr;34(4):373-80
references.pmid: 8506610
references.citation: Infect Immun. 2000 Mar;68(3):1048-53
references.pmid: 10678906
references.citation: Infect Immun. 2006 Aug;74(8):4724-34
references.pmid: 16861660
references.citation: FEMS Microbiol Lett. 2005 May 15;246(2):191-8
references.pmid: 15899405
references.citation: J Nat Toxins. 1998 Oct;7(3):193-213
references.pmid: 9783259
references.citation: Peptides. 2001 Oct;22(10):1621-7
references.pmid: 11587790
references.citation: Microb Pathog. 2006 Apr;40(4):177-83
references.pmid: 16517115
references.citation: Lett Appl Microbiol. 2002;35(3):181-4
references.pmid: 12180937
references.citation: Genet Mol Res. 2003 Mar 31;2(1):63-76
references.pmid: 12917803
references.citation: Infect Immun. 1978 Mar;19(3):943-9
references.pmid: 640738
references.citation: J Infect Dis. 2004 Jun 15;189(12):2334-6
references.pmid: 15181583
references.citation: Lancet Infect Dis. 2002 Nov;2(11):677-85
references.pmid: 12409048
references.citation: J Clin Microbiol. 1988 Jan;26(1):38-40
references.pmid: 3343313
references.citation: J Clin Invest. 2003 Dec;112(11):1620-5
references.pmid: 14660735
references.citation: Vaccine. 2004 Oct 22;22(31-32):4191-202
references.pmid: 15474709
references.citation: Infect Immun. 1998 Nov;66(11):5183-9
references.pmid: 9784520
references.citation: Trends Microbiol. 1998 Feb;6(2):54-61
references.pmid: 9507639
references.citation: J Dairy Sci. 1996 Jun;79(6):1021-6
references.pmid: 8827466
references.citation: MMWR CDC Surveill Summ. 2000 Mar 17;49(1):1-62
references.pmid: 10789699
references.citation: Peptides. 2000 Sep;21(9):1301-11
references.pmid: 11072116
references.citation: Nat Rev Microbiol. 2006 Jan;4(1):36-45
references.pmid: 16357859
references.citation: Appl Environ Microbiol. 2007 Jun;73(12):3845-9
references.pmid: 17449696
references.citation: Braz J Med Biol Res. 2006 Mar;39(3):387-91
references.pmid: 16501818
references.citation: Z Naturforsch C J Biosci. 2003 Nov-Dec;58(11-12):879-84
references.pmid: 14713169
references.citation: J Ethnopharmacol. 2005 Jan 4;96(1-2):335-9
references.pmid: 15588686