| Ixeris Sonchifolia (Bge.) Hance is a biennial herb, the compositae family, also called Kudiezi. Its aerial part is a traditional Chinese medicine (TCM) when it grows two years, which could clear fever and toxic material, alleviate pain and facilitates drainage of sores. Mordern research found that the herbs could be used in promoting coronary flow, improving cardiac circulation, inhibitting platelet aggregation and enhancing the activity of fibrinoclase.The main chemical compositions are flavonoids, such as luteolin, apigenin, luteolin-7-O-β-D-glucuronide, apigenin-7-O-β-D-glucoside.The total flavonoids extraction and purification process of the herbs was studied in this paper, and also included the content changing law with growth period and in different parts (root, stem, leaf, flower, fruit). At last, the antioxidant activity and the antibacterial activity of the crude extracts and the purity extracts were tested. Those researches would provide some references for its comprehensive development and utilization, the main conclusions as followings:1. The different extraction methods of the total flavonoids were compared, and the optimum process parameters of each method were identified. The parameters of ethanol reflux extraction are temperature 80℃, ethanol concentration 80%, counter-flow two times, extraction time 2h, water-to-feed ratio 1:25. The parameters of microwave-assisted extraction are ethanol concentration 65%, microwave power 300w, counter-flow two times, extraction time 2.5min, water-to-feed ratio 1:25. The extraction rate of the microwave-assisted extraction method is higher than the ethanol reflux extraction method, so it is the optimum extraction method for the herbs.2. The macroporous resin has good isolation and purification role for the total flavonoids. It ascertains the optimum macroporous resin which has well effects in purification the total flavonoids from the herbs is XAD-16 macroporous resin. The optimum parameter is sample concentration 3.0 mg/mL, PH=4.0, maximum sample amout 14.25mg/g humid resin, rate of adsorption 2BV/h, ethanol concentration 80% with 6BV, ethanol rate of adsorption 1BV, the flavonoids purify is as high as 89.1%, and the yield is 49.78%.3. In the paper, it is determined that the content of the total flavonoids in different growth peritod and different parts of the herbs, the total flavonoids content in the flower-bud stage reach the highest to 19.79%, and the total flavonoids content of the leaves is the highest, the content of die leaves in flower-bud stage is 30.45%. It provides the reference for the optimum collecting time and the medicine parts. 4. The antioxidant activity of the crude and purity extracts was compared and evaluated systematically, the results show that there are a good antioxigant ability in vitro, and the purity extracts have better effects than crude extracts on DPPH radical, and in eliminating superoxide anion, the reduction, but little worse in eliminating the hydroxyl radical. So it can be sure that the purity extracts have the better antioxigant ability.5. The antibacterial activity of the crude and punity extracts was compared and show some function. The concentration of the crude extracts and the purity extracts in antibacterial to staphylococcus-aureus is 0.625 mg/mL,1.25 mg/mL repectively, in anti-colibacillus are 1.25 mg/mL and 5.0 mg/mL, means that the crude extracts have the better antibacterial activity. The antibacterial activity to the gram-positive bacteria staphylococcus-aureus is better than to the gram-negative bacteria escherichia coli.The innovative points lie in the following:ascertaining the best process parameters of the microwave-assisted extraction, the optimum macroporous resin in purifing the total flavonoids, and the best process parameters, firstly comparing the antioxidant activity and the antibacterial activity of the crude and purifing extracts, enriching the research contents of the herbs'biological activities.
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