Screening of some plants from Northern Argentina for their antimicrobial activity.
OBJECTIVE
Screening of antimicrobial activity in 25 plant species from Northern Argentina.


RESULTS
Inhibition of microbial growth was measured by a microplate assay with an oxidation-reduction indicator (Alamar Blue). Test organisms were: Escherichia coli, Salmonella typhimurium, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus and Enterococcus faecium. Weak inhibitory activities (MIC=0.5 mg dry matter ml(-1)) were found in methanolic extracts of Rivina humilis, Crateva tapia, Funastrum claucum and Schinopsis balansae. Stronger bacteriostatic power was detected in Vassobia breviflora (MIC=0.25 mg ml(-1) against Staphylococcus aureus, and 0.5 mg ml(-1) against Enterococcus faecium). This activity was purified five-fold by extraction with dichloromethane, and it was found equally effective against susceptible or antibiotic-resistant strains of Staph. aureus. In addition, the purified extract was synergistic with gentamicin, and it was bactericidal at 24 h, with a concentration of 0.25 mg ml(-1).


CONCLUSIONS
There is a significant antimicrobial activity in Vassobia breviflora.


CONCLUSIONS
Further studies will be required to disclose the potential importance of these findings.
Salvat
A
A
Instituto de Patobiología, Centro Nacional de Investigaciones Agropecuarias, INTA-Castelar, Buenos Aires, Argentina.
Antonnacci
L
L
Fortunato
R H
RH
Suarez
E Y
EY
Godoy
H M
HM
D000900:Anti-Bacterial Agents / Q000032:analysis / Q000494:pharmacology*; D001118:Argentina; D004926:Escherichia coli / Q000187:drug effects; D007709:Klebsiella / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D010936:Plant Extracts / Q000494:pharmacology*; D010946:Plants, Medicinal; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D012475:Salmonella / Q000187:drug effects; D013211:Staphylococcus aureus / Q000187:drug effects
D000900:Anti-Bacterial Agents; D010936:Plant Extracts