COMPARATIVE EVALUATION OF ANTIMICROBIAL EFFICACY OF AQUEOUS AND ALCOHOLIC EXTRACTS OF YARROW AGAINST PATHOGENIC MICROORGANISMS.

Yarrow ( Achillea. millefolium ) has been used as a spice and medicinal plant in many ancient cultures from olden times. Today, biochemical investigations have shown different bioactive components responsible to medicinal and therapeutic properties of yarrow, in particular the antimicrobial effect of it. The aim of this study is in vitro assessment of potential of inhibitory function of aqueous and alcoholic extract of yarrow on some pathogenic microorganism: s taphylococcus aureus, escherchia coli, pseudomonas aeruginosa .

Materials & Methods: The yarrow plants were used in this investigation, produced in around of Urmia. The extracts were used in five dilutions (10%, 20%, 30%, 40%, 70% and neat). Also microorganisms were used in this examination were staphylococcus aureus (ATCC25923), escherchia coli (ATCC25922), pseudomonas aeruginosa (ATCC27853) . The agar disk diffusion test was used as microbiological examination.

Results: According to the results of this investigation, minimum inhibition concentration was approximate 30% and also the most sensitive organism to both extracts of yarrow was staphylococcus aureus and the least sensitive organism to these extracts was pseudomonas aeruginosa (P<0.05) .

Conclusion: With attention to our findings and other related reports in this field, it could be concluded that aqueous and alcoholic extract of yarrow have considerable antimicrobial effect on some pathogenic bacteria. Therefore, before application of these extracts as antimicrobial agent, it must be evaluated in vivo and clinically.