| The Herba Epimedii(family Berberidaceae) is widespread in Asia, Europe and the Middle and Far East. As a famous traditional Chinese herbal medicine, the Herba Epimedii made from the dried aerial parts of Epimedium brevicornum Maxim., Epimedium sagittatum(Sieb. et Zucc.) Maxim., Epimedium pubescens Maxim., Epimedium wushanense T.S. Ying. and Epimedium koreanum Nakai. They have been commonly used in the treatment of cardiovascular diseases and other chronic illness(infertility, amnesia and asthenia, impotence and senile functional diseases) in China for over 2000 years.Although the related research of epimedium has very deep, but there are still some work to be further in-depth and conduct, in this paper, It is detailed study that Optimization of icariin extraction; Determination of amino acids; Optimization of ultrasonic extraction of phenolic compounds; Studies on activity of ACE, α-glucosidase inhibitory activity and nitrite scavenging from different extracts of unprocessed and processed Epimedium brevicornum Maxim.; Study on the hypolipidemic activity and antioxidant activity in vitro of polysaccharide and extract etc. to further provide reference for future research and development and utilization of Epimedium brevicornum Maxim. The main research contents and results are as follows:(1) Optimization of icariin extraction from Epimedium brevicornu Maxim by supersonic wave using central composite design and response surface methodology. The ultrasound-assisted extraction of Icariin from Epimedium brevicornu Maxim was optimized using response surface methodology and central composite design(CCD). Based on single factor tests, the effects of ethanol concentration, ultrasonic extraction time, liquid to solid ratio and their interactions on extraction rate were studied using CCD method. The optimal ultrasonic extraction conditions based on ridge analysis were: ethanol concentration 68%, ultrasonic extraction time 23 min, liquid to solid ratio 32 m L/g. Under the optimum conditions, the extraction yield of total Icariin was 0.661%, which was close to the theoretical value of 0.663%.(2) Determination of amino acids in Epimedium brevicornu Maxim. by RP-HPLC. To establish a method for determination of the contents of 21 free and hydrolyzed amino acids from Epimedium brevicornu Maxim. by pre-column derivatization RP-HPLC. The samples were derivated with phenyl isothiocyanate and HPLC method was adopted. Gradient elution chromatography was applied to determine contents of free and hydrolyzed amino acids in E. brevicornu. The 21 amino acids had good linearity in the range of 0.0019~2.7000 μmol·m L-1(the coefficients of correlation were all over 0. 9995). The average recoveries of free amino acids were 86.7%~100.1%( RSD =0.61%-2.7%, n =6); the average recoveries of hydrolyzed amino acids were 90.3%~100.0%( RSD =0.41%-2.0%, n =6).(3) Optimization of ultrasonic extraction of phenolic compounds from Epimedium brevicornu Maxim using response surface methodology and evaluation of its antioxidant activities in vitro. The ultrasound-assisted extraction of phenolic compounds from Epimedium brevicornu Maxim was modeled using response surface methodology. A Central Composite Design(CCD) was employed to optimize three extraction variables, including ethanol concentration(X1), extraction time(X2), and ratio of aqueous ethanol to raw material(X3), for the achievement of high extraction yield of the phenolic compounds. The optimized conditions are X1 of 50%, X2 of 27.5 min, and X3 of 250 m L/g. Under these conditions, the experimental yield is 4.29 ± 0.033%(n=3). The antioxidant activity was evaluated using the DPPH assay and ferric-reducing antioxidant power(FRAP). And it indicates that the phenolic compounds from Epimedium brevicornu Maxim possess significant antioxidant activity. HPLC analysis reveals that the main phenolic compound in the extract product was identified as gallic acid, catechin(Cianidanol), p-hydroxybenzoic acid, vanillic acid, caffeic acid, ferulaic acid, rutin, benzoic acid and quercetin.(4) Studies on activity of ACE, α-glucosidase inhibitory and nitrite scavenging from different extracts of unprocessed and processed Epimedium brevicornum Maxim. To determine the activity of angiotensin converting enzyme(ACE), α-glucosidase inhibitory and nitrite scavenging from different extracts and water decoction of unprocessed and processed Epimedium brevicornum Maxim. The unprocessed and processed E. brevicornum were extracted with different solvent, and the extracts’ ACE inhibitory activity was detected by HPLC. The extracts’ nitrite scavenging capability and their α-glucosidase inhibitory activity were measured by spectrophotometry respectively. For the ACE inhibitory activity of the extracts, the results showed it only appears in petroleum ether extract, and the unprocessed IC50 was lower than the processed. For α-glycosidase inhibitory activity, the activity was shown in dichloromethane, ethyl acetate, methanol, water extracts and water decoction of the unprocessed E. brevicornum, and the dichloromethane extract of the processed had no inhibitory activity, at the same time, the inhibitory activity of the other extracts and water decoction of the processed was lower than the unprocessed, but not obvious. In the aspect of nitrite scavenging activity, the processed E. brevicornum showed a certain activity in petroleum ether, dichloromethane, ethyl acetate extracts and water decoction, the unprocessed showed a certain ability of scavenging activity in dichloromethane, ethyl acetate, the methanol extracts and water decoction. The icariin’s contents of different extracts and water decoction of unprocessed and processed E. brevicornum were determined by HPLC. The results showed that icariin can be detected in ethyl acetate, methanol, water extracts and water decoction, at the same time, the unprocessed E. brevicornum generally show a higher content than the processed.(5) Study on the hypolipidemic activity and antioxidant activity in vitro of polysaccharide from the Epimedium brevicornu Maxim. The present study was undertaken to evaluate antihyperlipidemic and in vitro antioxidant activity of polysaccharides from Epimedium brevicornu Maxim(PEMB). The antioxidant activity of PEMB was evaluated using the DPPH assay and ferric-reducing antioxidant power. Hyperlipidemic model was established. Prophylactic administration and remedial administration were evaluated in this study. The mice were randomly divided into six groups including normal control group, model group, positive control group, high, medium and low dose group, after the end of the experiment were measured serum levels of total cholesterol(TC), triglyceride(TG), low density lipoprotein(LDL-C) and high density lipoprotein(HDL-C) content. Results: The results showed that free radical scavenging activity on 2,2-diphenyl-picrylhydrazyl(DPPH)(IC50 47.21±0.39 μg/m L) and high reducing power(EC50 271.67±1.86 μg/m L) in vitro chemical assays.(6) Study on the hypolipidemic activity and antioxidant activity in vitro of ethanol from the Epimedium brevicornu Maxim. The present study was undertaken to evaluate antihyperlipidemic and in vitro antioxidant activity of ethanol from Epimedium brevicornu Maxim(EEBM). Methods: The ultraviolet light span method was adapt to determination the content of content of total phenolics and flavonoids from EEBM. The antioxidant activity of EEBM was evaluated using the DPPH assay and ferric-reducing antioxidant power. Hyperlipidemic model was established. Prophylactic administration and remedial administration were evaluated in this study. The mice were randomly divided into six groups including normal control group, model group, positive control group, high, medium and low dose group, after the end of the experiment were measured serum levels of total cholesterol, etc. Results: The results showed that EEBM contains 71.62% flavonoids and 12.31% phenolics and free radical scavenging activity on 2,2-diphenyl-picrylhydrazyl(DPPH)(IC50 35.12±0.48 μg/m L) and high reducing power(EC50 147.35±1.386 μg/m L) in vitro chemical assays. |
PDF Full Text Request