Comparative evaluation of antimicrobial effect ofArtemisia vulgarisessential oils extracted from fresh and dried herb

Abstract

The study was conducted to determine antimicrobial activity of Artemisia vulgaris essential oil (AVEO), and to see the effect of drying of herb for AVEO extraction on its antimicrobial activity. AVEO was extracted from fresh chaffed herb and dried powdered herb and tested on 1199 strains of 113 species of pathogenic, potentially pathogenic and environmental microbes belonging to 33 different genera, 1172 were bacteria and 27 were yeast and moulds. Although more number of strains was sensitive for AVEO extracted from fresh herb (23%) than AVEO from dried herb (21%), difference was statistically insignificant (p, 0.40) between AVEOs extracted from fresh or dried herb. About 19.9% of bacterial and 25.9% of fungal isolates were sensitive to AVEO. Interestingly, oxidase positive strains (63.7%) including those of pseudomonads (60%), aeromonads (53.6%), spore forming bacilli (71.6%), Pastuerella (83.3%) and micrococci (66.7%) were comparatively more sensitive (p, <0.001) than oxidase negative bacteria (8.3%) to AVEO. Of the 114 clinical isolates (associated with illness in human and animals) belonging to 25 bacterial species, 23 (20.2%) were sensitive to AVEO. Clinical isolates were significantly (p, 0.03) more sensitive than isolates from healthy human and animals (12.6%). Thus for better antimicrobial activity AVEO should be extracted from fresh herb. The AVEO may be an effective therapeutic agent of future either as such or as the source of some novel antibacterial molecule(s) particularly against oxidase positive bacteria.