Pharm Biol. 2017 Dec;55(1):1054-1060. doi: 10.1080/13880209.2017.1287744.
- 1a Department of Geography and Environmental Science , University of Zimbabwe , Harare , Zimbabwe.
- 2b
Department of Research and Specialist Services, Division of Livestock
Research , Grasslands Research Institute , Marondera , Zimbabwe.
- 3c Department of Veterinary Science , University of Zimbabwe , Harare , Zimbabwe.
- 4d
Department of Animal Production and Technology , School of Agricultural
Sciences and Technology, Chinhoyi University of Technology , Chinhoyi ,
Zimbabwe.
- 5e Department of Livestock and Veterinary Services, Division of Veterinary Services , Harare , Zimbabwe.
- 6f Department of Animal Science , University of Zimbabwe , Harare , Zimbabwe.
Abstract
CONTEXT:
Salvadora
persica L. (Salvadoraceae), Colophospermum mopane (J.Kirk ex Benth.) J.
Léonard (Leguminosae) and Dichrostachys cinerea (L.) Wight & Arn.
(Leguminosae) crude extracts are used by local farmers against many
livestock infections with little or no side effects usually associated
with synthetic antimicrobials. However, their efficacy has rarely been
tested.
OBJECTIVE:
These
plants were tested for potential antibacterial activity against
clinical isolates of Staphylococcus aureus ATCC33862 and Escherichia
coli ATCC25922. Minimal inhibitory concentrations (MIC) of the crude
plant extracts were determined.
MATERIALS AND METHODS:
Aqueous
and methanol extraction of 100 g each of the bark of C. mopane, roots
of D. cinerea and leaves of S. persica was done by placing the samples
in 250 mL of either water or methanol. Nutrient broth was used as growth
medium for the bacteria, and McFarland standard for bacterial
standardization. 2,3,5-Triphenyltetrazoliumchloride (TTC) was the
indicator salt. Each of the aqueous and methanol extracts (100 μL) was
tested. Gentamycin and ampicillin were the controls.
RESULTS:
MIC
of aqueous extracts ranged from 1.03-14.6 mg/mL against S. aureus, and
from 12.1-34.3 mg/mL against E. coli. Methanol extracts ranged between
5.31 and 9.64 mg/mL against S. aureus, and between 7.86 and 13.6 mg/mL
against E. coli. Aqueous and methanol extracts of S. persica were
significantly higher (p < 0.05) than C. mopane and D. cinerea.
DISCUSSION AND CONCLUSION:
Colophospermum
mopane, S. persica and D. cinerea exhibited antibacterial activity,
with methanol extracts performing better than aqueous extracts,
justifying use as ethnoveterinary medicine. Further study to isolate the active components should be pursued.
KEYWORDS:
Ethnoveterinary medicine; Staphylococcus aureus; Escherichia coli; minimum inhibitory concentration