the study on the phytochemical and antibacterial activity of achillea eriophora by microdilution assay

abstract essential oils (eos) of achillea eriophora, extracted by hydrodistillation and their constituents were analyzed by gas chromatograph (gc) and gc/mass spectrometry using retention indices and fragmentation patterns. the antibacterial effects of the eo was assessed on several food-borne pathogens, namely staphylococcus aureus, bacillus cereus, escherichia coli o157:h7, salmonella enteritidis, and listeria monocytogenes using microdilution technique by elisa reader device. results showed that the essential oil content of the plant was more than other achillea species. gc analysis of the eo confirm the presence of 36 constituents that the main condstituents were camphore(28.65%), 1,8 cineol(26.95%), camphene (5.98%), β-pinene (4.8%) α-pinene (4.2%) and borneol(4%). mic of the eo agains gram positive baccteria ranged 0.15 – 0.75 mg/ml and against gram negative bacteria was 1.5-3 mg/ml. the most sensitive pathogene was s. aureus and the most tolerant one was s. enteritidis.