Preparation Of Saponins From Aralia Elata And Its Antihyperlipidemic Function

Aralia data is a prennial Araliaceae with high medicinal and edible values and it is rich in saponins,polyphenols,polysaccharides and other biologically active ingredients,and has significant effects in the treatment of acute and chronic inflammation,neurasthenia,myocardial ischemia,hyperlipidemia,diabetes and anti-tumor.Saponin has been proved to be the main bioactive substance in Aralia elata.On this basis,this study analyzed bioactive substances in Aralia elata materials that are from several origins,researched the extraction,purification and hypolipidemic effect of Aralia data saponin.The pivotal conclusions are as follow.(1)The nutrients and bioactive substances contents of Aralia elata that are collected from Dandong,Baishan,Yichun,Liaoyang,Benxi,and Tonghua were determined.The results showed that the water content,crude fat content,crude protein content,crude ash content,crude chlorophyll content,total carbohydrate content,reducing monosaccharide content,polyphenol content,flavonoid content,saponin content,and Vc content of these Aralia elata varied in the range of 80.52%?84.06%,0.51%?1.53%,2.30%?2.89%,9.03%?10.56%,18.24?38.20mg/g,33.57?44.66mg/g,0.80?1.26mg/g,27.55?34.83mg/g,and 98.08?122.23?g/g,respectively.Besides,Aralia elata is rich in potassium,calcium,sodium,magnesium,and phosphorus,the mineral content of these materials varied from 24571.76 to 25110.25?g/g.According to these results,Aralia elata originated Dandong possessed the most exploitation potential,and thus it was selected in the study of the next stage.(2)The yield of the three extraction methods was optimized by Box-Behnken response surface method to determine the optimal extraction process.Results showed that the optimum vacuum coupled ultrasound extraction parameters were l:25.1(w/v),80%of ethanol,57.7OC of extraction temperature,273.9W of power,50min,and 0.0787MPa of vacuum.The productivity of Aralia elata saponin was 4.21%under these conditions.The optimum salting-assisted enzymatic method parameters were pH 5.405,61.3?,7.74%of disodium phosphate,90min,and 1.5%of cellulose.The productivity of Aralia elata saponin was 3.97%under these conditions.The optimum parameters of ultrasonic assisted ethanol extraction were 1:25(w/v),82.95%of ethanol,82.62?,270W of power,78.88min.The productivity of Aralia elata saponin was 3.87%under these conditions.The yields ranked optimum vacuum coupled ultrasound extraction>salting-assisted enzymatic extraction>ultrasonic assisted ethanol extraction.(3)The purification effects of saponin using 10 kinds of macroporous resins were analyzed by static screening.The results indicated that D101 macroporous resin had the best effect on the recovery of saponins.The optimum conditions of D101 applied saponin purification were 0.20 mg/mL of load volume and pH 3.0 in the absorption process,and 80%of ethanol,3BV/h of flow rate in the elution process.Under these conditions,the purity of yielded saponin increased significantly from 8.06%to 35.40%.The purified product of the saponin resin was further purified by silica gel column.The silica gel eluent was determined by thin layer chromatography to be chloroform:methanol:water(3:1:0.1),and the elution component was qualitatively identified by color reaction and thin layer chromatography and the purity was increased to 50.65%.(4)The effect of Aralia elata saponin on lipid metabolism related enzymes and antioxidase in mice liver were analyzed using cholate binding capacity and serum lipid profiles as criteria to investigate its hypolipidemic activity.The results showed that saponin had good binding ability to cholate and the binding capacities of silica chromatography purified Aralia elata saponin against sodium glycocholate,sodium taurochalete,and sodium cholate were 1.71?mol/100mg,1.93 ?mol/100mg,and 0.91 ?mol/100mg,respectively.In terms of serum lipid profiles,Aralia elata saponin can inhibit the increase of bodyweight and improve liver index in hyperlipidemic mice,and can significantly(P<0.05)decrease the TC,TG,LDL-C,and AI level,increase the HDL-C level.In terms of antioxidase,Aralia elata saponin significantly(P<0.05)increased the activities of HL,LPL,SOD,CAT,and GSH,while lowered the MDA content in mice liver when comparing with the hyperlidemic group.