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 mg.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 percent 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.
Subject(s)
Anti-Bacterial Agents , Drug Resistance , Enterotoxins/analysis , In Vitro Techniques , Rauwolfia/toxicity , Staphylococcal Infections , Staphylococcus aureus/isolation & purification , Staphylococcus aureus/pathogenicity , Enzyme-Linked Immunosorbent Assay , Methods , MethodsABSTRACT
From the hexanic extract of the stem from Swartzia apetala Raddi var. glabra were isolated one stilbene (1), one flavanone (2), one pterocarpan (3), one triterpene (4) and a mixture of three steroids (5 to 7). The crude extract and the compounds isolated were submitted to evaluation of the antifungal activity against nine yeast standard ATCC of the Candida genus. Among the compounds only the triterpene (4) and the mixture of steroids (5 to 7) showed no activity. The structures of the compounds were determined by spectral data analysis of GC/MS and ¹H and 13C NMR (1D and 2D experiments), as well as comparison with literature values.
Do extrato hexânico da madeira de Swartzia apetala Raddi var. glabra foram isolados um estilbeno (1), uma flavanona (2), um pterocarpano (3), um triterpeno (4) e uma mistura de esteróides (5 a 7). O extrato bruto e as substâncias isoladas foram submetidas à avaliação do potencial antifúngico usando nove cepas padrão ATCC do gênero Candida. Entre as substâncias testadas apenas o triterpeno (4) e a mistura de esteróides (5 a 7) não apresentaram atividade. As estruturas das substâncias foram determinadas através da análise dos espectros de CG/EM, e RMN (1D e 2D) e comparação com dados da literatura.
ABSTRACT
Este trabalho foi realizado em maracujazeiro amarelo (Passiflora edulis Sims f. flavicarpa) cultivado em condições de campo, no município dos Campos do Goytacazes-RJ, com o objetivo de determinar os teores de rutina, vitexina e flavonóides totais e dos nutrientes N, P, K, Ca, Mg, S, B, Fe, Zn, Mn e Cl em folhas de diferentes posição no ramo. O experimento constou de 10 tratamentos, que consistiam na coleta das folhas 1 (mais nova) a 10 (mais velha) de um mesmo ramo, com quatro repetições. A amostragem foliar foi feita em março de 2004 e cada amostra constou de 20 folhas coletadas de 20 plantas por repetição. Os teores de rutina, vitexina e flavonóides totais variaram em função da posição ou idade das folhas, sendo maiores nas folhas mais jovens ou na região apical dos ramos do maracujazeiro amarelo. Os teores de flavonóides totais, expressos em vitexina, diminuíram da folha 1 para a folha 8, de 24,4 para 14,9mg g-1 de matéria seca. Os teores de N, P, K e Zn foram maiores e os de Ca, Mg, B, Cl e Mn foram menores nas folhas mais jovens. Os teores de S e Fe não variaram com a posição da folha no ramo.
The research was carried out in yellow passion fruit plant (Passiflora edulis Sims f. flavicarpa) grown under field conditions in Campos dos Goytacazes-RJ, Brazil, with the aim to evaluate the concentrations of rutin, vitexin, total flavonoids, N, P, K, Ca, Mg, S, B, Fe, Zn, Mn and Cl in leaves at different positions in the branch. The experiment consisted of 10 treatments: leaves 1 (the youngest) to 10 (the olderest) of the same branch, with four replicates. Leaf sampling was done in March 2004, and each sample consisted of 20 leaves from 20 plants. The total concentration of rutin, vitexin and total flavonoids varied in function of the position or age of leaves, being higher in youngest leaves or in the aplical region of the plant branches. The total flavonoids concentration decreased from leaf 1 to leaf 8 of the branch 24.4 and 14.9mg g-1 of dry matter, respectively. The concentrations of N, P, K and Zn were higher in the youngest leaf but the concentrations of Ca, Mg, B, Cl and Mn were lower. The concentrations of S and Fe did not vary with leaves positions in the branch.