Isolation,Analysis And Function Evaluation Of Low Caloric Sweetener Mogrosides

Momordica grosvenori is a kind of traditional Chinese plant used as herb and food. And has been used as Chinese herb for more than 300 years in kswangxi province. Mogrosides were proved to be the main active components of Momordica grosvenori,so the research of Mogrosides draw people's much attention. This paper was performed on purification, analysis, preparation and determination of Mogrosides, and the antioxidant effect and hypoglycemic action of Mogroside extract were also discussed. These main results were indicated as follows:1. Isolation and Purification of MogrosidesThe isolation and purification of Mogrosides from momordica grosvenori by column chromatography with macroporous resin H was investigated. The optimum condition of isolation and purification was that Mogroside crude extract was successively eluted with water, 30% ethanol and 60% ethanol at 40癈 at pH 9.0, and then the 60% ethanol eluate was collected, concentrated and freeze-dried. The high purity of Mogroside extract (MGII) was obtained with the Mogroside content of 108.13% (specrophotometry) and the Mogroside-V content of 69.24% (HPLC), increasing by 32.90% and 41.21% over Mogroside crude extract respectively.2. HPLC Analysis and HPLC-ESI/MS/MS Analysis of MogrosidesA high performance liquid chromatographic method for the analysis of Mogrosides has been established. The condition was: column, C18 ODS (250x4.6mm ID, 5um); eluting solvent, acetonitrile-water, 23:77(v/v); flowrate, 0.5mL/min; temperature, 30癈; sensitivity setting, 0.04AUFS; wave length of UV detector, 21 Onm.In this paper, the Mogroside components of MGII were roughly identified by HPLC-ESI/MS/MS. The results showed the main Mogroside components in MGII may be 11-oxo-mogroside mogroside-V mogroside-IV mogroside-VI and Siamenoside I.3. Preparation, Identification and Quantification of Mogroside-VA high performance liquid chromatographic(HPLC) method for the preparation of Mogroside-V was studied. The condition was: column, Shim-Pack PREP-ODS (0.25m X20.0 ) ; mobile solvent, acetonitrile-water, 20.5:79.5(v/v); flowrate, 8.0mL/min. AndMogroside-V was identificated by using the methods of MP UV IR andHPLC-ESI/MS/MS.The quantification of Mogroside-V by HPLC was established. The experimental results showed that this method was simple, accurate and rapid, had a good linear relationship between the peak area and the concent of Mogroside-V (R2=0.9986), high recoveries(95.36%-102.47%) and better relative standard deviation (1.33%).4. Antioxidant Effects of Mogroside ExtractsThe antioxidant effects of different Mogroside extracts in vitro were studied. Mogroside extracts had scavenging effects on hydroxyl radical (OH) and superoxide anion radical (O2-).And had the inhibiting effects on lipid peroxidation with rat liver in vitro. It also could protect liver from peroxidation induced by Fe + or H2O2, inhibit the mitochondria swelling and hemolysis of red blood cells. Mogroside-V could significantly scavenging hydroxyl radical (OH) and superoxide anion radical (O2-), so this showed that Mogroside-V were one of the main antioxidative components in the extract of Mogroside. In different antioxidant systems, different Mogroside extracts had different antioxidant effect.5. Antidiabetic Effect of Mogroside ExtractsThe glucose-lowering effect of the extracts of Mogroside (MGC) on hyperglycemic mice induced by Alloxan was studied in this paper.Alloxan-induced diabetic mice were fed with MGC at dose of 50mg/kg.bW 100mg/kg.bw 300mg/kg.bw 500mg/kg.bw respectively for 30d. The blood glucose levels and antioxidation levels were assayed after the last fedding. And the results showed: (1)MGC at dose of 100mg/kg.bw, 300mg/kg.bWs 500mg/kg.bw could significantly lower the fasting blood glucose and the hypoglycemic effect of MGC at dose of 100mg/kg.bw was the best. (2)MGC could decrease the content of TC, TG and enhance the content of HDL-C of alloxan-induced diabetic mice, so it could restore the blood lipids level of diabetic mice (p < 0.01 o...