In the experiment we tested antibacterial
activity of citrus juices and apple cider vinegar on
Staphylococcus aureus NCTC 1249, clinical strain
Methicillin-resistant Staphylococcus aureus, Escherichia
coli ATCC 25922, Enterococcus faecalis ATCC 29212,
Staphylococcus aureus ATCC 2523. Antibacterial
activity was tested using agar well diffusion method.
Results were obtained by measuring the diameter of
zone of inhibition around the wells. The highest zone of
inhibition (18.5 mm) was observed around 100%
concentration of apple cider vinegar on E. faecalis.
Lemon juice of 100% concentration also had an impact
on E. faecalis where the zone of 14 mm appeared. Zones
of 15.5 mm and 13.5 mm were obtained for 100% and
75% of lemon on S. aureus ATCC 2523 respectively. S.
aureus NCTC 1249 showed to be resistant to all
concentration of all juices except for 100%
concentration of apple cider vinegar where we got
reduced growth. Methicillin-resistant S. aureus was
resistant to all concentrations of apple cider vinegar
and zones of 15 mm and 14 mm were present around
100% and 75% lemon juice respectively. E. coli showed
to be resistant to all concentration of citrus juices.
Apple cider vinegar concentrations of 100% and 75%
slightly reduced the growth of E. coli. Results obtained
in this experiment suggest that different concentrations
of citrus juices and apple cider vinegar have a
prominent antibacterial effect on gram positive bacteria
and less prominent effect on gram negative bacteria as
in this case E. coli.
Keywords : Antibacterial Activity; Citrus Juices; Apple Vinegar; Gram Positive Bacteria; Gram Negative Bacteria.