Phytochemical analysis and anti-microbial activities of Artemisia spp. and rapid isolation methods of artemisinin

Abstract

AbstractArtemisia species are important traditional medicinal plants of Ethiopia which are used for the treatment of infection and non-infection health problems. The genus Artemisia (Astraceae) consists of about 500 species worldwide. In this study, the main aim was to investigate chemical components ofArtemisiaspp. (A. abyssinica,A.absinthiumand A.annua) and evaluate their antimicrobial activities against bacterial strains. The results indicated that the crude extract of these plants was effective against selected bacterial strains. Here we isolated the well-known antimalarial drug artemisinin (7 mg, 0.004%) fromArtemisia annualeaves using a rapidn-hexane fractionation method.Then-hexane extract ofA. abyssinica,ethyl acetate extract ofA. absinthiumandn-hexane ofA.annuashowed varying degrees of inhibiting effect against bacterial strains such as Staphylococcus aureusATCC 25923 T,Salmonella enteritidisATCC13076T,Klebsiella pneumoniaeATCC1053T,boydiiATCC1233T,Escherichia coliATCC 25922 T, hospital acquiredAcinetobacter baumannii.The ethyl acetate extract ofArtemisia absinthium(A.abe) showed the maximum inhibiting effect (35 mm) againstA. baumannii. The minimum zone of inhibition (< 3 mm) was recorded for test extract of A.ap againstKlebsiella pneumoniaeATCC1053T. Ethyl acetate extract ofA, absinthium(A.abe) was more effective against these selected bacterial strains and the zone of inhibition ranged from 5 to 35 mm. The minimum inhibition zone (8 mm) was detected againstS. typhimuriumATCC 13311 Tfor both A.ac and n-hexane- EtOAc fraction (8:2) ofA, abyssinica. The maximum zone of inhibition (25 mm) for fraction (A.ach F4) ofA, abyssinicaobtained by column chromatography was recorded againstS. pyogen ATCC19,615. However, there was no zone of inhibition detected forboydiiATCC1233Tdue to these test extracts. Significant variations (P ≥ 0.05) were observed between all test extracts of these medicinal plants at 95% of confidence intervals. In this study, clear zones of inhibition were detected for the positive control (standard impregnated disks). Based on our results we recommend that various species of Artemisiaspp. seem to have the potential for in-depth investigation for various antimicrobial activities that assisting the effort in searching for antimicrobial lead compounds.