| Polygonum cuspidatum Sieb.et Zucc.is one of the traditional chinese medicinal materials and it was included in "Chinese pharmacopoeia" of 2000 version.The biological active ingredients in Polygonum cuspidatum Sieb.et Zucc.contains stilbene,flavonoids and etc.Modern pharmacology proves that resveratrol in stilbene has biological activities such as antioxidation,anti-free-radicals,anti-aging,anti-cancer,anti-vascular disease,etc;flavonoids has the functions of analgesia,antiviral,cut down the blood lipid,reduce the blood sugar,antioxidation and other medical efficacy.At present,the purification research of effective components from Polygonum cuspidatum Sieb.et Zucc.get more and more attention by people.Our work focuses on the separation and purification of resveratrol and flavonoids in Polygonum cuspidatum Sieb.et Zucc.The results obtained as follows:1.Composite enzymatic technology was applied to extract the resveratrol from Polygonum cuspidatum Sieb.et Zucc.Optimizing the extraction conditions by orthogonal design test and obtained the optimal extraction conditions: Composite enzymatic=0.50%(m/m),extract temperature T = 45?,p H=6.5,extract time t = 5.0 h,Solid-liquid ratio 1/22(g/m L),extraction times n=2.The extraction ratio of resveratrol were 75.66% with the purity of 3.80%,and the purity was about 10 folds of the raw material(0.4%).2.32 kinds of MARs were investigated in separation and purification of resveratrol crude extract from Polygonum cuspidatum Sieb.et Zucc.,and the result shown that MARs LZ-94+LZ-78+LZ-76 have the best separation effect for resveratrol,the optimal adsorption condition(C=0.25mg/m L,T=45?,p H=3.0,V=60 m L,t =9.0 h)and the desorption condition(T= 55?,ethanol content=70 %,t=2.5 hours,p H=4.0)were obtained.Under the optimal conditions,the purity of resveratrol reached 19.3 0% with the recovery of 78.60%.Adsorption kinetics results show that the adsorption process of MARs fitted better to the pseudo-second-order kinetic model.The adsorption process of macropoes and mesopoes were controlled by the Intra-particle-diffusion mainly,and the Homogeneous-particle-diffusion controlled the adsorption process of microporous mainly.The adsorption thermodynamics of MARs fitted better to the Freundlich model,it means that adsorption behavior of MAR-mixed bed on resveratrol was multilayer physisorption.3.Because the purity of resveratrol obtained in the earlier part was low,in this part,the preprocessing method was applied to crude extracts of resveratrol before purified by MARs technology.The extraction method and technology was researched.Then,comparing the extraction effect of different organic solvents on resveratrol extracts,it colud be find that E/D=3/1 present the best extraction effect on resveratrol,and the optimal extraction volume ratio was Vw/Vo= 2/3,extractive time interval was 60 min,extraction was most suitable for 5 times,in this condition,extraction rate of resveratrol was 88.81% with the purity of 66.50%.To ensure the polydatin could fully hydrolyzed into resveratrol with less loss by decomposition,and the extraction method was environment friendly since the E and D is internationally recognized green solvents in chemistry circles.The sample after extraction purified by silica gel column chromatography method and the resveratrol obtained has the purity of 73.70% and recovery rate of 61.60%.The sample after extraction purified by MARs technology and the resveratrol obtained with the purity of 87.12% and recovery rate of 81.10%.The results shown that on the premise of purifying the same quality of resveratrol,MARs technology was superior to silica gel column chromato graphy for purification of resveratrol.4.The ultrasonic-assisted method was applied to extract the flavonoids from Polygonum cuspidatum Sieb.et Zucc.,The optimal extraction conditions were: extract time t = 34 min,extract temperature T=45?,Ultrasonic power W=80W,Solid-liquid ratio 1/20(g/m L),ethanol content=60%,extraction times n=5.The extraction yield of flavonoids were 94.50% with the purity of 31.00%.5.32 kinds of MARs were investigated in separation and purification of flavonoids crude extracts from Polygonum cuspidatum Sieb.et Zucc.,and the result shown that MAR LZ-72 has the best separation effect for flavonoids,the optimal adsorption condition(C=2.50mg/m L,T=30?,ethanol content=10 %,V =60.0m L,t =20.0h)and the desorption condition(T=55?,ethanol content=90 %,V=110m L,t =20.0h)were obtained.Under the optimal conditions,the purity of flavonoids reached 82.50% with recovery of 89.70%.Adsorption kinetics results show that the adsorption process of LZ-72 fitted better to the pseudo-second-order kinetic model.The adsorption process of macropoes and mesopoes were the Intra-particle-diffusion controlled mainly,and the Homogeneous-particle-diffusion controlled the adsorption process of microporous mainly.The adsorption thermodynamics of LZ-72 fitted better to the Freundlich model,it means that adsorption behavior of LZ-72 of flavonoids was multilayer physisorption. |
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