Studies On The Extraction Purification And Antioxident Activity Of Chinese Olive Leaves Polyphenols

Chinese olive(Canarium album L.),a precious resource for traditional medicine,an important specialty resource in Fuzhou City, Fujian Province at the same time,possesses some pharmacological functions. The phenolic compounds from Chineseolive leaves was extracted, isolated and purified in this project. What was more, theresearch for anti-oxidation effect of olive leaves polyphenols was operated. Besidesthe olive leaves polyphenol active components were analyzed by HPLC. Therefore,an important theory basis for development and utilization of olive leaves polyphenolswas provided.(1) Concentration of ethanol, extraction temperature, material-liquid ratio,extraction time, and extraction times were investigated separately to showing theinfluence on the extraction rate of olive leaves polyphenols. Based on theSingle-factor experiments, this study applied Box-Benhnken method to conduct aThree Factor-Three Level experiment, using the value of polyphenols extraction rateas response values to analyze the response surface methodology experiments. Theresults showed that the optimal technological condition for the extraction of oliveleaves polyphenols was as follows. The ratio of material to liquid was1:25, extractiontemperature was72℃, extraction time was2.4h and ethanol concentration was50%.In this optimal condition, polyphenols extraction rate was14.7%by using extractiontechnology.(2) Microwave-assisted Extraction of olive leaves polyphenols was studied byMicrowave Extraction Technology.Based on the Single-factor investigation and theBox-Behnken response surface analysis principle, ethanol concentration, Microwavetime and ratio of water to material were selected at three levels to be investigated theinfluences on the extraction of olive leaves polyphenols. In order to have the optimumcombination, quadratic regression equation of the extraction rate was established. Thisinvestigation showed that the optimum extraction condition of olive leavespolyphenols was63%ethanol, extraction time was30s solid-liquid ratio was1:25,extraction power was240W. Under this optimum condition, the extraction rate reached could reach16.15%, which was9.86%higher than using ethanol extrationunitarily.(3) Using macroporous resin adsorption method to purify olive leavespolyphenols crude extraction was studied. Becasuse of higher adsorption anddesorption capacity, HP-20resin was selected from6kinds of resin for the separationof phenolics through the static adsorption and desorption tests.The optimumadsorption conditions were as follows, the polyphenols liquid solubility was4mg/mL,the flow velocity was3BV/h, and Ph4. The optimum desorption conditions were thatthe ethanol concentration was50%(v/v), and flow velocity was3BV/h. In that case,the content of phenolic in the purified sample was71.2%.(4)Taking Vc and tea phenolic as reference, respectively using Fenton reactionand pyrogallol autoxidation methods, olive leaves polyphenols effect onscavenging·OH and·O₂-of was studied. The test results presented that olive leavespolyphenols had the ability to scavenge·OH and·O₂-in certain concentration range.With the same concentrations, the ability to scavenge·OH and O₂-was weaker thanto scavenge Vc, but stronger to scavenge Vc than·OH under low concentrations.Olive leaves polyphenols anti-oxidation ability test showed that Olive leavepolyphenols had strong anti-oxidation ability.(5)Using HPLC, the components of olive leaves polyphenols determination wasanalyzed. The chromatography conditions were below. Utilize Reversed-phase C18chromatography column, adapte variable gradient with mobile phase tomethanol-water-acetic acid solution,280nm detection wavelength,35℃columntemperature, and1mL/min flow rate. Thus the main components for the olive leavespolyphenols could be analyzed, and together the gallic acid could be depatchedduring these conditions.