INVESTIGATING THE ABILITY OF NATURAL MATERIALS TO INHIBITION OF SOME PATHOGENIC BACTERIA

Background: Pathogenic bacteria represent a major concern in that they can affect public health. Thus, an ongoing race between pharmaceutical manufacturers and the elevation of bacterial resistance to antibiotics is at its peak. In order to overcome this obstacle, recent studies are directed toward using natural alternatives that can replace antibiotics and have a significant impact on these pathogenic bacteria. Aim: the main aims of this study were (1) finding a natural and eco-friendly alternative for traditional chemical antibiotics that could give a good inhibition for the growth of some of the well-known pathogenic bacteria (2) testing the ability of five plant suspensions which are clove, hibiscus, mustard, cinnamon suspensions, and lemon juice as well as acetic acid (4%) to inhibit the growth of four pathogenic bacterial species which are Klebsiella pneumonia, Enterobacter cloacae, Escherichia coli, and Staphylococcus aureus. (3) compare the effects of the plant's suspension with the effect of several known antibiotics and explain their mode of action. Methods: the aqueous plant extract was prepared from the dried plant parts, and the purified bacteria colonies were obtained from hospital samples. Then, the ability of the plant extracts against these bacteria was tested using the agar-well diffusion method, and the inhibition zone for each bacteria was determined. Results: The results showed that K. pneumoniae was sensitive to the used antibiotics except chloramphenicol, nitrofurantoin, and ampicillin, and it was sensitive for all the extracts except for mustard. While E. cloacae was resistant to tetracycline, co-trimoxazole, ampicillin, and nitrofurantoin, it had an intermediate sensitivity to chloramphenicol. In contrast, it was sensitive to all extracts except for the mustard extract. However, E. coli was resistant to all antibiotics except for tetracycline, amikacin, nitrofurantoin, and colistin, while it has intermediate sensitivity to gentamycin, though it was sensitive to all plant extracts except mustard extract and acetic acid. Staphylococcus aureus was resistant to kanamycin, cotrimoxazole, chloramphenicol, ampicillin, and nitrofurantoin, though it has intermediate sensitivity to gentamycin and colistin, while it was sensitive to all plant extracts as well as acetic acid. Discussion: From the results, it was obvious that the most effective extracts were hibiscus and clove, followed by cinnamon, lemon juice, and acetic acid, while only S. aureus was sensitive to mustard extract. Conclusions: The results of the study showed that the natural plants' extracts were effective against different pathogenic bacteria with dissimilar degrees of effect.