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.