| 1. The extraction of effective constituents from Chinese medicine Acanthopanax Senticosus Harms Flavonoid and saponin compounds from the leaves of Acanthopanax Senticosus Harms have been extracted by means of microwave-assisted extraction (MAE) technique. The influence of some operation conditions, such as ethanol concentration in extraction solvent, microwave irradiation time and processing pressure, etc., on the extraction yield of those compounds has been studied. The highest extraction yield can be obtained when 50% ethanol is used as the extraction solvent for flavonoids, and it is 70% ethanol for saponins. When ethanol concentration is over 60%, the selection of saponins is increased with the increase of ethanol concentration. When the process pressure is lower than 700 kPa the yields of flavonoids and saponins are increased with the increase of pressure, then they are not change. The extraction time obtained the highest yields of saponins is shorter than the time obtained that of flavonoids. This means that saponins are easy to be decomposed. The ratio of saponins and flavonoids is decreased with the increase of extraction time. Three microwave assisted extraction methods, pressurized microwave extraction (PMAE), atmospheric pressure reflux microwave extraction(AMAE) and flow microwave extraction(FMAE), of flavonoids and saponins from Traditional Chinese Medicine Acanthopanax Senticosus Harms were studied. The influence of extraction time of every method on the extraction yield of total flavonoid and total saponin were investigated. The experimental results indicated the complete extraction time of the pressurized microwave extraction is 10min, that of atmospheric pressure reflux microwave extraction is 14min and that of flow microwave extraction is 10min. 8 h is need to complete extraction by Soxlhet extraction method. Comparing with Soxhlet extraction, not only the microwave extraction take shorter time, but also the yields of flavonoids and saponins obtained by using microwave extaction methods are higher significantly. 2. Analysis of extract from Acanthopanax Senticosus Harms by HPLC-DAD-MSn A high-performance liquid chromatography (HPLC) for the determination of flavonoids from the extract of leaves of Acanthopanax Senticosus Harms was developed. The determination was performed using HPLC-diode array detection (DAD) and a Zorbax ODS C18 column. The four flavonoids (hyperin, rutin, quercitrin and quercetin) were separated by methanol-water (0.5%HAC) gradient elution and monitored at 254 nm. The detector response is linear from 0.02 to 20μg of hyperin ( y= 4121.57x + 33.97, R = 0.99951 )and rutin (y=2985.00x-16.18 R=0.99963), 0.01 to 20μg 0f quercitrin (y=4649.12x+15.52 R= 0.99868) and quercetin (y=5702.63x-30.62 R=0.99807). The recoverys of the four flavonoids are 96.1%, 98.6%, 105.1% and 101.7%, and RSD of determination for them are 1.97%, 2.44%, 1.47% and 2.80%, respectively. 50% ethanol is used as extraction solvent to extract the efective constituents in the leaves of Acanthopanax Senticosus Harms. The extract is separated on a resin chromatographic column and prepared on the semi-prepared HPLC. The target compound is obtained, which has been elucidated as chlorogenic acid. 3. The change of chemical constituents from the leaves of Acanthopanax Senticosus Harms in the process of extraction The change of flavonoids in the process of extraction was investigated. The results show that flavonoids are easy changed at a high pressure for a long period of time, for example, rutin is decomposed into quercetin. The higher pressure is, the faster the rate of change is. By the comparing of MAE and Soxhlet extraction methods, it is shown that more constituents and higher extraction yields could be obtained by means of MAE. 4. The extraction of effective constituents from Chinese medicine Epimedium Koreamum Nakai The total flavonoids and icariin in Epimedium Koreamum Nakai have been extracted by atmospheric pressure microwave-assisted extraction (AMAE), pressurized microwave-assisted extraction (PMAE), ultrasonic extraction (UE) and RE (RE). The influence of extraction parameters on the extraction yields of epimedin A, epimedin B, epimedin C and icariin has been evaluated. The experimental results demonstrate that the advantage of PMAE and AMAE over conventional RE is validated, in which the extraction time isdramatically reduced and the yields of flavonoids are effective improved. Although the UE method can be carried out within a short time, the extraction yields of flavonoids are lower compared with other extraction methods. 5. The analyses of extract from Epimedium Koreamum Nakai by HPLC-DAD-MSn The extracts from Epimedium Koreamum Nakai have analyzed by HPLC-DAD-ESI-MSn, as a result, the four flavonoids in the extracts have been identified as epimedin A, epimedin B, epimedin C and icariin. 6. The change of chemical constituents of extract from Epimedium Koreamum Nakai in the process of extraction The change of flavonoids in the process of extraction is investigated. The results show that epimedin C are easy changed into icariin at a high pressure for long period of time. 7. The change of chemical constituents of Aconite roots and Aconitum kusnezoffii during processing Diester-type aconitum alkaloids in Aconite roots are decomposed by means of boiling and microwave heating. The decomposition speed during microwave heating is faster than that during boiling. The processing condition of Aconitum kusnezoffii is optimized by using orthogonal test. For mesaconitine, the optimal conditions of processing is that dip time, decoction time, dry time and the temperature are 9 h, 10 h, 18 h and 80℃respectively. For hypaconitine, the optimal conditions of processing are that dip time, decoction time, dry time and the temperature are 9 h, 8 h, 18 h and 80℃respectively. The contents of Diester-type aconitum alkaloids in different processed Aconite roots are determined by HPLC, and the experimental results show that these constituents in different processed Aconite roots are different.
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