The Extraction And Applied Research Of Saponins And Mucoprotein In Yam

Yam was adopted as raw materials.The modern chemic method was chosen to extract and purify saponins and mucoprotein in yam,then the anti-diabetic and reducing blood lipid activity of saponins and the antioxidative activity of mucoprotein in yam was studied.According to the single factors experiments and orthogonal experimental design,the optimum extracting condition of total saponins in yam use water bath shaking method was showed as follows:the concentration of ethanol was 80%,extracting temperature was 60 ℃,solid-liquid ratio was 1:10,extracting time was 3 h.The optimum extracting conditions of ultrasonic method of total saponins in yam were showed as follows:ultrasonic temperature was 50 ℃,ultrasonic time was 60min,ultrasonic power was 90P%.It was found that the ultrasonic wave extraction compared with the water bath shaking extraction could save the extracting time and decrease the extracting temperature,but could not increase the rate of saponins extraction remarkably.AB-8 type macroporous resin was used in the purification experiment through static adsorption.Determined the best purified conditions through dynamic adsorption,the conditions was showed as follows:pH value of absorbing solution was 6,the absorbing velocity of flow was 1.0 mL/min,the adsorption time was 60 minutes,the proportion between the volume of absorbing solution and resins was 6:1,the concentration of ethanol was 60%.The proportion between the amount of elutent and resins was 8:1,the desorption time was 50 minutes.Then collect 60%ethanol eluent,concentrate and vacuum drying.After purification the content of crude saponins increased to 65.38%.Use chemical methods to analysis the yam total saponins which have purified the result proved yam total saponins are steroid saponins.Then ues the method of ultraviolet and HPLC-MS analysis,the results prove yam total saponins contain the following five kinds of steroidal saponin:dioscin,diosgenin,protodioscin,gracillin,methyl protodioscin.Alloxan-induced diabetic mice fed with the purification of saponins in yam at low dose group(100mg/kg.bw)middle dose group(200mg/kg.bw)and high dose group(400mg/kg.bw)respectively for 14d.The blood glucose levels and blood-lipid levels were assayed after the last feeding.The results showed:(1)Compared with the group of Alloxan,the positive control group,the low dose group,the middle dose group and the high dose group had significant differences(P<0.01).The saponins could evidently reduce blood glucose value,and the effect of the saponins at high dose was the best.(2)The SOD activity in the middle dose group(200mg/kg.bw)and the high dose group(400mg/kg.bw)compared with the model group had significant difference(P<0.01)and the effect of the saponins at high dose was the best.(3)The content of triglyceride have influence but not obvious.(4)Yam total saponins can low down total cholesterol,the middle dose(200mg/kg.bw)group and the high dose group(400mg/kg.bw)compared with the group of Alloxan,had significant difference(P<0.05),and the effect of the saponins at high dose was the best.(P<0.01).The extraction of mucoprotein with ultrasonic wave for the single factor and orthogonal experiment,determined the best extraction process:extracting temperature 50℃,extracting time 70 min,solid-liquid ratio 1:20,ultrasonic power 70%,the yield of mucoprotein is 2.936%.Then remove the free protein and dialysis,separate the mucoprotein preliminary,after determination the protein content in the mucoprotein is 38.76%,the polysaccharide content is 25.23%.Adopting the methods pyrogallol autooxidation,Fenton reaction to recearch the ability of remove hydroxyl radicals and superoxide anion radicals and the reducing capacity of mucoprotein.In the selected concentration range,the results showed that:The scavenging hydroxyl free radical capability of mucoprotein is better than Vc,up to a maximum of 43.71%,The scavenging superoxide anion radical capability is increased with the centent of mucoprotein,but less than Vc and BHT.The reducing ability is increased with the centent of mucoprotein.