Abstract: Green Fructus forsythiae essential oil was extracted by supercritical carbon dioxide extraction(SCDE)technique.The minimum inhibitory concentration(MIC)of the essential oil were determined by the test in vitro on the tested strains(Escherichia coli,Staphylococcus Aureus and Bacillus Subtilis).The effects of temperature and pH on bacteriostasis of the essential oil were also studied.Hydroxyl radical scavenging method,DPPH radical scavenging method,phosphomolybdenum complex assay and ferric thiocyanate method were used to evaluate antioxidant activities of Green Fructus forsythiae essential oil and the results were compared with those of antioxidants such as butylated hydroxytoluene(BHT)and ascorbic acid(V_C).The experimental results showed that the antibacterial effect of Green Fructus forsythiae essential oil enhanced with pH decreasing or with the increase of temperature.Results also showed that Green Fructus forsythiae essential oil in different antioxidant evaluation methods were reflected with certain antioxidant activities,but the overall antioxidant capacity was weaker than BHT.

Key words: Green Fructus forsythiae essential oil, bacteriostasis, antioxidation