The Extraction And Purification Of Tea Saponin And The Extraction Of Tea Seed Polysaccharide In Camellia Cake

The comprehensive utilization of the camellia cake may have bright future andremarkable economic benefit because there is abundant tea-seed resource in china。Quantitative determination of tea saponin by spectrophotometry and HPLC was studied,Comparison of two methods of quantitative analysis. The HPLC was comfirmed to be used as the method which analysing the content of tea saponin in camellia cake.Meanwhile, The phenol-sulfuric acid method was used to analyse the tea seed polysaccharide;The extraction technology of tea oil, tea saponin and tea seed polysaccharide was optimised;Using macroporous resin to sublimate tea saponin and gaining the high purity tea saponin; A whole process has be proposed and there was the posibility to get hold of tea oil,tea saponin and tea seed polysaccharide from camellia cake.The main content of research is as follows:(1) Quantitative analysis of tea saponinA reverse-phase high performance liquid chromatography method(HPLC)for determination of the tea saponin was studied. After VP-ODS(250 mm×4.6 mm,C18, 5μm)was chosen as analytical column and methanol-water (v/v= 9/1)at a flow-rate of 1.0 mL/min as mobile phase, the UV signal was detected at 280 nm. The value of abscissa shows the mass concentration,and y-axis, area. The linear equation was Y=3.02×106X-1.16×104, Linear correlation coefficient is r=0.9995。The recovery of teasaponin is 97.02%～102.82%。Through method of HPLC determined the content of tea saponin in camellia cake was 11.89%.The method was accurate, rapid and simple, this is a good analysis method.(2) Quantitative analysis of tea seed polysaccharideDetermination of tea seed polysaccharide using phenol-sulfuric acid method, determination its absorbance inλmax is 490nm. The linear equation was Y=173.48X-28.262(Y said glucose/μg, X said absorbance), the linear correlation coefficient is r=0.9965. Through experiments, we can get the conversion factor of tea seed polysaccharide f= 4.2783. According to the formula:Y= mCf/M, we can calculate the purity of tea seed polysaccharide(3) Extracting of tea oil and tea saponinBase on the different physical nature and chemical nature of tea oil and tea saponin,the differetn extracting agent were used and the extracting effects were compared.The petroleum ether((boiling range 60℃-90℃)and methanol were used to extract tea oil and tea saponin respectively. And the method of soxhlet extraction was used to extract tea oil,the ultrasonic method was used to extract tea saponin.The characteristics of petroleum ether extracting tea oil are high yield,low poison, low cost and hight rate of recovery.Extracting the tea oil under the optimum condition (heating time 2 h, the liquid-to-solid ratio 7 mL/g, reflux speed 5 min/time) and the extraction rate of tea oil is 7.5%.Using the methanol as the extracting agent,and extracting the tea saponin by ultrasonic method. The optimal conditions is:ultrasonic frequency is 40kHz,the temperature of extracting is 40℃, time at 25 min, the liquid-to-solid ratio is 6 mL/g, ultrasonic power is 250W, and the yield of tea saponin is 14.2%(4) Purification of tea saponinAbsorbing the tea saponin by macroporous resin AB-8,and uppering sample after the pH has been ajusted to 5,the result are shown:adsorption reached 32.1 mg/every mL of colophony,rate of absorption reached 88%. And elute it with 1% NaOH,the most impurity and pigment has been removed.and then,desorb it with 85%～95% methyl alcohol.The result is shown:when the pH of upper sample liquid is 5 and after being absorping for 2 h,removing the impurity and pigment by 1% NaOH,and eluting it by 95% methyl alcohol (proportion of eluting liquid and upper sample liquid is 5:1),condensing the eluting liquid which was gained under this condition concentrated to a certain volume,after precipitated by acetone.Finally, it has been turned into crystal by methyl alcohol,a kind of high purity tea saponin crystal which inpurity can be 95.6% can be gained.(5) Extraction of tea seed polysaccharideUses the ultrasonic extraction to extract the tea seed polysaccharide from the camellia cake. The optimal conditions were obtained through single factor and orthogonal experiments:time at 15 minutes, the liquid-to-solid ratio is 16mL/g, ethanol concentration is 50%, extraction temperature is 50℃and the extraction rate of tea seed polysaccharide reached 8.5%.