Antioxidant and Antimicrobial Activities of Echinacea purpurea L. Extracts. الانشطة المضادة للأکسدة والمیکروبات فی مستخلصات نبات القنفدیة الارجوانیة

Echinacea purpurea L. (E. purpurea) is one of the most important medical herbs belongs to   Asteraceae family. This plant contains many chemical compounds. It has also demonstrated numerous biological  activities as both antioxidant and antibacterial.  Methanol was used to extract  green plant sample and consider as crud extract. This last one was partitioned into  four solvents i.e. petrolium ether, CH2Cl2, C2H5COOCH3 and C4H9OH  . The obtained fractions extracts were tested for their total phenolic content (TPC), total flavonoid content (TFC). Antioxidant activities were carried out using three methods I.e phosphomolybdenum, reducing power and radical assay DPPH.  Crude methanolic extract was subjected to six microbial strains included fungi, yeast and bacteria i.e: Aspergillus oryzae , Candida albicans, Saccharomyces cerevisiae, Alternaia solani and Escherichia coli (G-), Streptococcus faecalis (G+). E. purpurea extracts had the highest effect of on  yeast (Saccharomyces cerevisiae) with average value of 15.0 mm 100 ppm extract. Results showed that the highest concentration of TPC for ethyl acetate extract  was 90.6 mg GAE/g dw wheras  pet. ether gave the lowest value of 33.83 mg GAE/g d.w. TFC was ranged from 146.53 to 322.23mg QE/g dw for ethyl acetate and methanol extracts, respectively. Butanol extract showed the highest antioxidant activity with average value of 70.22 μg/ml.