In vitro antibacterial activity of Quercus infectoria gall extracts against multidrug resistant bacteria
- Author:
Wan Nor Amilah, W.A.W.
;
Masrah, M., Hasmah, A.
;
Noor Izani, N.J.
- Publication Type:Journal Article
- From:Tropical Biomedicine
2014;31(4):680-688
- CountryMalaysia
- Language:English
-
Abstract:
Antimicrobial activities of plants have long been evaluated for their promising use
as antimicrobial agent and in minimizing the unwanted resistance effects of microorganisms.
The study was conducted to evaluate the antibacterial activity of Quercus infectoria gall
crude extracts against multidrug resistant (MDR) bacteria in vitro. The screening test was
determined by disc diffusion technique using sterile filter paper discs impregnated with 1 mg/
disc (50 mg/ml) aqueous and ethanol extracts of Q. infectoria galls tested on five selected
MDR bacterial strains. The minimum inhibitory concentration (MIC) was determined using
the twofold serial micro dilution technique at concentration ranging from 5.00 mg/ml to 0.01
mg/ml. The minimum bactericidal concentration (MBC) was determined by sub culturing the
microtitre wells showing no turbidity on the agar plate to obtain the MBC value. Both extracts
showed substantial inhibitory effects against methicillin resistant coagulase negative
Staphylococcus (MRCoNS) and methicillin resistant Staphylococcus aureus (MRSA). A slightly
reduced inhibitory zone diameter was observed with MDR Acinetobacter sp. while no inhibitory
effect was displayed among the extended spectrum beta lactamases (ESBL) K. pneumoniae
and ESBL E. coli isolates. A significant difference in the zone sizes between both extracts
was only observed in MRSA (p < 0.05). The MIC values ranged from 0.08 mg/ml to 0.63 mg/ml
for aqueous and ethanol extracts against MRSA, MRCoNS and MDR Acinetobacter sp. while
their MBC to MIC ratio values were 2 and less. The Q. infectoria gall extracts have shown
very promising in vitro antibacterial activities and may be considered as a potentially good
source of antimicrobial agent especially against MDR Gram positive bacteria.
- Full text:W020150601565216399925.pdf
