| Rhodiola crenulata(HK.f.et.Thoms)H.Ohba is an important medicinal and edible plant that grows mainly in high altitude or cold regions.It has very important utilization value and development prospects in many fields such as medicine,food,skin care products and health medicine.Salidroside is an important active ingredient in Rhodiola crenulata.It not only inhibits tumor growth,improves diabetes symptoms and protects nerves,but also has a wide range of applications in cosmetics,shower gels,shampoos and other daily chemicals.The pursuit of a new,low-cost,effective and fast salidroside separation technology can obtain better economic benefit from it.In this paper,firstly,the fingerprint of Rhodiola crenulata was established by HPLC,and the quality of the medicinal materials was preliminarily evaluated by chemical pattern recognition.In addition,imprinted polymers with salidroside as template molecules were prepared by molecular imprinting technology.It is expected to provide a simple and efficient new method for the separation and enrichment of salidroside.The main research contents of the subject are as follows:(1)The fingerprint of Rhodiola crenulata was established by HPLC,and the similarity evaluation results showed that the quality of Rhodiola crenulata from different origins had good consistency.The quality of medicinal materials was evaluated by chemical pattern recognition methods,and a total of 8 difference markers that caused differences in sample quality were obtained;The composition content of samples from different origins was significantly different.Among them,the salidroside and tyrosol content in the Naqu area of Tibet were the highest,at 17.5997and 4.4803 mg·g-1,respectively,and the rosavin content in the Aba Prefecture of Sichuan was the highest at 9.0146 mg·g-1.(2)The tyrosinase inhibitory activity test results of salidroside and tyrosol showed that salidroside and tyrosol had an inhibitory effect on tyrosinase activity.Salidroside IC50=27.08±3.761?g·m L-1,tyrosol IC50=71.02±2.956?g·m L-1.The inhibitory effect of salidroside on tyrosinase activity was better than that of tyrosol.The effect of salidroside and tyrosol on the catalysis pathway of tyrosinase was analyzed by high performance liquid chromatography.It may be that salidroside and tyrosol were catalyzed and oxidized by tyrosinase instead of L-DOPA.(3)Using Rhodiola crenulata from Naqu of Tibet as a raw material,the extraction temperature,ethanol concentration,liquid-to-material ratio,and extraction time were used as investigating factors to conduct a single-factor experiment,and the extraction process of salidroside was optimized.The optimized process conditions were as follows:the ultrasonic assisted extraction method was used,the extraction temperature was 60?,the ethanol concentration was 65%,the ratio of material to liquid was 1:20,the extraction time was 50 min,and the extraction rate was 1.89%.(4)The quantum chemical calculation method was used to screen the functional monomers and solvents for the synthesis of polymers.The effects of different monomers,solvents,monomer dosages and synthesis methods on the molecular recognition ability of polymers were investigated through experiments to optimize the synthesis conditions of polymers.The optimized conditions were as follows:the bulk polymerization method was used,THF was used as the solvent,acrylamide was used as the functional monomer,and the molar ratio of salidroside,acrylamide and ethylene glycol dimethacrylate was 1:5:20.(5)The molecularly imprinted polymers(MIPs)of salidroside was prepared.The MIPs was characterized by infrared spectroscopy,scanning electron microscopy,static adsorption and dynamic adsorption experiments.It was confirmed that the polymers synthesized by adding salidroside had a larger specific surface area,indicating that salidroside was combined with acrylamide in a non-covalent form.The Langmuir model was used to analyze the adsorption performance of MIPs,and the results showed that the maximum adsorption capacity was Qm=25.97 mg·g-1.The adsorption kinetic characteristics of MIPs accorded with the quasi-second-order kinetic model.(6)MIPs were applied to the solid phase extraction of salidroside in the extract of Rhodiola crenulata.As a result,when the concentration of salidroside in the Rhodiola crenulata extract was 0.462 mg·m L-1,the adsorption capacity of MIPs was6.84 mg·g-1,the eluted amount of salidroside was 6.32 mg·g-1 and the elution rate was92.4%. |
PDF Full Text Request