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Rauvolfia grandiflora (apocynaceae) extract interferes with staphylococcal density, enterotoxin production and

Lanamar de Almeida Carlos1, Kenas Aguiar da Silva Amaral, Ivo José Curcino Vieira

  • 1Laboratório 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.

Brazilian Journal of Microbiology : [Publication of the Brazilian Society for Microbiology]
|September 14, 2013
PubMed

Insights

Rauvolfia grandiflora extract significantly inhibited Staphylococcus bacteria growth and reduced enterotoxin production. This natural compound also restored sensitivity to penicillin in resistant strains, offering potential for new antimicrobial therapies.

Area of Science:

  • Microbiology
  • Pharmacology
  • Natural Products Chemistry

Background:

  • Staphylococci bacteria cause significant human and animal infections.
  • Developing novel antimicrobial drugs against pathogenic bacteria is a pharmaceutical priority.

Purpose of the Study:

  • To investigate the in vitro antimicrobial and anti-enterotoxin effects of Rauvolfia grandiflora methanol extract (RGE).
  • To evaluate RGE's impact on Staphylococcus aureus and Staphylococcus epidermidis growth, drug sensitivity, and enterotoxin production.

Main Methods:

  • In vitro testing of RGE against ATCC and clinical strains of Staphylococci.
  • Spectrophotometry and ELISA assays to measure cell density and enterotoxin production.
  • Disk diffusion method to assess antimicrobial effects and drug sensitivity post-RGE treatment.

Main Results:

  • RGE (1.2 μg.mL(-1)) significantly inhibited Staphylococcus cell growth.
  • Penicillin-resistant strains demonstrated restored sensitivity to penicillin after RGE treatment.
  • RGE treatment precluded enterotoxin production in 20% of treated S. aureus bovine strains.

Conclusions:

  • Rauvolfia grandiflora extract exhibits significant antimicrobial properties against Staphylococci.
  • RGE interferes with staphylococcal cell density, enhances antibiotic efficacy, and reduces enterotoxin secretion.
  • These findings underscore the potential of RGE as a basis for new anti-staphylococcal therapies and disease prevention strategies.
Keywords:
Rauvolfia grandifloraStaphylococcus aureusantimicrobial activity.enterotoxin

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