| Hibiscus manihot L. is an annual herbage plant of malvaceous abelmosk. Hibiscus manihot flower contain plenty of bioactive components, especially flavonoids. Flavonoids have strong antioxidant activity. They have prominent functions in against anoxia of heart and brain , enhanced antioxidant function in metabolism, postponed dumps catatonia and enhanced kidney function, and so on.The components of hibiscus have been analyzed and the extractive technology and antioxidant activity of the hibiscus manihot flower total flavones have been studied in the article. Main results are as follows:1. In fresh hibiscus manihot flower, the content of water, ashes, protein and fat is 92.27 percent, 4.08 percent, 7.32 percent and 2.88 percent respectively. The content of Ca and Zn are rich in the flower, each of them is 56250μg/g and 4130μg/g. And the content of Cu is poor. In the five parts of root, stem, leaf, flower and seed, the total flavones content of the flower is the highest.2. The extracting technology of total flavones of hibiscus manihot flower have been optimized. And the results indicate that the content of total flavones of hibiscus manihot flower is the highest, arriving at 7.48 percent of the dry flower powder, which in the conditions are these: in 80 degrees centigrade, 80 percent ethanol as extracting solvent, the ratio of solid to liquid is 1∶100 (g/mL), extracting 2 times, 2h each time, and extracting pH value is 10. And the priority rating of the extracting factors are these: extracting solvent, time, temperature, ration of solid to liquid, pH value and extracting times.3. Four types of different polar macro resins such as DM130, DM301, X-5 and AB-8 are studied to purify hibiscus manihot flower total flavones with static and dynamic adsorption. The purification efficiency of AB-8 macro resin is the best of the four macro resins. In the static adsorption of hibiscus manihot flower total flavones, the adsorption ration of AB-8 macro resin is the highest, which reaches to 48.97 percent, and the desorption ration of DM301 macro resin is the highest, which arrives at 87.36 percent. The best technology of AB-8 macro resin to purify the hibiscus manihot flower total flavones are these: the concentration of sample liquid is 6.0 mg/mL, and the sample liquid pH value is 4.0, 60 percent ethanol as washing solvent, and the washing velocity of flow is 4.0 mL/min.4. The antioxidation activity is studied with the crude extracted total flavones liquid and the purified total flavones liquid. The eliminating DPPH·capability of the purified total flavones liquid is better than the crude extracted total flavones liquid. To eliminate DPPH·in the same concentration of 4.0mg/mL, the elimination ration of crude extracted total flavones liquid is 72.47 percent, but the purified total flavones liquid is 84.80 percent when it flowed through AB-8 macro resin. In the fat antioxidation experiment, the antioxidant effect of compound antioxidant is better than the single antioxidant. For example, the antioxidant effect of the compound antioxidant of 0.20 percent the extracted total flavones and 0.05 percent V_C is the best.
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