| Mulberry leaves and plumula nelumbinis have specific nutritional and medicinal values, which are considered as food-medicine herbs approved by National Ministry of Health. The alkaloids and polysaccharides existed in mulberry leaves have effectiveness for preventing and treating diabetes mellitus, and the flavonoids in mulberry leaves exhibit good antioxidant activities. Plumula nelumbinis contains rich alkaloids which can be used for treating hypertension. The volatile oil extracted from plumula nelumbinis containsβ-sitosterol which is recently reported having anti-cancer function. In this thesis, some advanced separation methods and technologies were explored to effectively isolate and purify the medicinal components from mulberry leaves and plumula nelumbinis. This study shows important academic value and social significance in developing modernization of traditional Chinese medicine and promoting comprehensive utilization of natual plants.Firstly, comprehensive experimental investigations were performed for establishing a successive process of separation and purification of alkaloids, polysaccharides and flavonoids from mulberry leaves, and the quantity control methods of the active components were also set up.The 80% ethanol solution was selected to extract the alkaloid of 1-deoxynojirimycin (DNJ) from mulberry leaves by ultrasonic-assistant method, where the extraction yield of DNJ was up to 0.117%. Then cation and anion exchange resin adsorption with 001×7 (fine) and 201×7 resins were used separately for further purifying DNJ. The effect of several factors, such as feed concentration and pH, eluent concentration on the recovery of DNJ were investigated. Under the optimum conditions, the recovery of DNJ was up to 77.5% , and the content of DNJ in the products was improved to 44.8%.The flavonoids in mulberry leaves were co-extracted with DNJ when 80% ethanol solution was used as the extraction solvent, where the total flavonoids yield in the extracts was 1.72%. The macroporous H-103 resin adsorption technology was further employed to investigate the possibility for effectively separation of flavonoids and DNJ. The adsorption conditions were optimized and the optimal experimental results show that the content of the total flavonoids could be 36.3% with recovery of 83.4%, and 99.2% of alkaloids could be remained in separated effluent.After extracting alkaloids and flavonoids from mulberry leaves with 80% ethanol solution, the remained residue was the useful raw material for the extraction of polysaccharides. The polysaccharide was separated by the processes including hot water extraction, activated carbon decolorization, precipitation with 20% ethanol solution and desiccation. The yield of the polysaccharide was 2.91%, and the contents of the neutral sugar and uronic acid were 20.9% and 51.5%, respectively. The structure of the mulberry leaves polysaccharide were further investigated. The molecular weight and monosaccharide composition of the polysaccharides were measured by high performance-gel permeation chromatography (HP-GPC) and pre-column derivatization HPLC, respectively. The IR and P1PH NMR spectra indicated that the polysaccharide in the mulberry leaves was mainly pectin, which was classified as high-methoxyl pectin.On the basis of the above investigations, a new process was designed for separation of alkaloids, polysaccharides and flavonoids from mulberry leaves simultaneously. The material balance was also carried out. It was indicated that the alkaloids, flavonoids and polysaccharides could be separated effectively by the new process, which was independent and non-interfering, the content of the alkaloids, flavonoids and polysaccharides in the products were up to 44%, 35% and 50%, respectively. Therefore the developed process would provide a new approach for comprehensive utilization of the mulberry leaves and developing modern traditional Chinese medicine.On the other hand, supercritical fluid extraction (SFE) of plumula nelumbinis oil containingβ-sitosterol with CO2 was performed. The factorial design with response surface analysis was employed to get the optimum extraction conditions. The yield of plumula nelumbinis oil could reach 12.2%, where the content ofβ-sitosterol was up to 7.38%. The comparison between SFE and solvent extractions demonstrated the higher extraction yield, superior product quality and no solvent residues for SFE.The differential mass transfer model of broken and intact cells (BIC) was presented to simulate the SFE process of the plumula nelumbinis oil at different conditions, where three adjustable parameters were reduced to two in order to improve the simulation. The values of average absolute relative deviation (AARD) were in range of 2.56-10.5%, indicated that the improved method had similar effect with BIC model with three adjustable parameters. The mass transfer coefficient in the fluid phase (kBfB)B Bwas estimated, which was in the range of 4.20×10-5 to 1.20×10-4 m/s in the investigated conditions. The mass transfer coefficient in the solid phase (ks) was fitted, which changed from 8.88×10-10 to 2.04×10-8 m/s. These parameters had clear physical meanings and could deepen the understanding of the SFE process theoretically.
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