Research Article
Ahmed S Ismail Soheir M Zal
Abstract
Objectives: This study was planned in order to assess the anti-inflammatory and antimicrobial potential of the different organs (leaf, flower and root) of Conyza dioscoridis (L.) Desf. Methods: A preliminary phytochemical and chromatographic screening of the ethanol (70%) extracts was performed prior investigation. Successive extraction of the plant organs was carried out with petroleum ether 60-80°C, chloroform, ethyl acetate and ethanol 90%, and percentage yield of extractives was determined. The anti-inflammatory activity of the total ethanol (70%) extracts was evaluated in-vivo by the carrageenan-induced rat paw oedema method, as compared to Indomethacin. The antimicrobial activity of the total ethanol and successive extracts was assessed by the agar dilution method on a set of bacteria and fungi; MICs were determined. Results: The acute toxicity study of the total ethanol (70%) extracts indicated their safety (LD 50 up to 5 g/kg body wt.). The ethanol (70%) extract of the leaf showed the highest percentage of oedema inhibition (76.20%). The in-vitro antimicrobial assay revealed that most of the fractions exhibited a significant activity against Mycobacterium phlei, as compared to the other tested strains (MICs ranging from 50 to 200 μg/ml); the lowest recorded MICs (50 μg/ ml) being those of the successive ethanol extract of the roots and the ethyl acetate extract of the leaves. In addition, the successive ethanol extract of the roots exerted a noticeable effect against Bacillus subtilis (MIC, 100 μg/ml). Conclusion: The data represented in this study demonstrate that the use of C. dioscoridis may lower the risk of microbial infections and exert an anti-inflammatory activity, probably due to the presence of phenolics. The use of extracts is recommended to achieve health benefits, rather than pure isolates due to the synergistic and additive effects of their components.