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Ursolic acid is a pentacyclic triterpenoid substances, has significant anti-tumor, anti-oxidation, anti-inflammatory, hepatoprotective, hypolipidemic effect. More difficult synthesis, usually extracted from biomass. This article discussed the process of separation and purification of Ursolic Acid from Hedyotis diffusa. Ursolic acid in Hedyotis diffusa extract analysis method. Qualitative analysis using thin-layer chromatography, analytical conditions: toluene: ethyl acetate: glacial acetic acid = 20:4:0.6 as developing agent, silica gel G plates as the stationary phase, iodine vapor as chromogenic reagent. RP-HPLC quantitative analysis, analytical conditions: methanol: water: acetic acid = 85:15:0.3 as the mobile phase, C18 column as the stationary phase, the flow rate was 0.6ml/min and the injection volume was 10μl, detection wavelength of 210nm, column temperature was 30 ° C. Solvent crude extract ursolic acid. The ethanol extraction solvent through single factor and orthogonal experiments, get the best extraction conditions: 95% ethanol at reflux temperature extracted twice, each time 1.5h, liquid to solid ratio of 8:1. By extraction experiment measured experiments containing ursolic acid in Hedyotis diffusa 3.57 × 10 -3 (g / g). Extraction rate of up to about 95% of the of ursolic acid under the above conditions, extract ursolic acid content of about 2.5%. Ursolic acid extracted preliminary purification by solvent. The first liquid to solid ratio of 10 (v / m) in petroleum ether to crude extract extract three times skim stock solution of 1:1, and then chloroform extracted twice. And then with acid precipitation i.e. by adjusting the pH value of the extract an alcohol solution to further purification ursolic, optimum conditions for the first to the alcohol solution of the sample with 10% NaOH solution was basified to pH11, the heating and stirring was allowed to stand , filtered; the filtrate was washed with 10% HCl solution was acidified to pH 2, and then the same acidity of the aqueous solution was diluted twice was allowed to stand, filtered and the precipitate was washed with water until neutral and dried in vacuo. The content of the final products obtained up to about 36%, the recovery rate of 72.6%. This paper also examines the refining process of column chromatography, the best chromatographic conditions through the single factor of 80 to 120 mesh silica gel as the stationary phase, mobile phase was chloroform to methanol system, gradient elution, elution speed 0.8BV / h is appropriate elution temperature controlled at 25 ° C. By column chromatography, the product the ursolic acid purity by more than 36% of the pre-column increased to more than 65%. Also preliminary exploration of the crystallization process. Finally, through the the MTF method examines the products in this article on the proliferation of cells K562/ADM inhibition, significant cytotoxicity.
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