Studies On The Extraction, Saparation And Purification Of Red Pigment And Procyanidin Of Red Skin Of Peanuts

Peanut resource,which is ranking the first place in the yield and export,is abundant in China.And there is a variety of active substances in the red skin of peanuts,the red pigment which can be used as natural and the procyanidin which can be used as the medicine of anti-cancer and anti-cardiovascular disease is among it.So it has a very important and far-reaching benefit of social and economic to use the peanuts and its by-product resources more rational and efficient.The main conclusions of this research are as follows:1.Research has been carried out on the technology of extracting red pigment and procyanidin from the red skin of peanuts assisted by ultrasonics.Ethanol has been selected to extract these two substances.Through single factor and orthogonal experiments,the effects on the extraction efficiency and gardenia of red pigment and the procyanidin content of the concentration of ethanol,the ratio of solid to solution,extraction time and the temperature were investigated.The optimum conditions were obtained as follows:the rate of solid to solution was 25∶1,ethanol concentration 60%,ultrasonic time 30 min and ultrasonic temperature 55℃.2. Research has been carried out on the technology of separating and purification of red pigment and procyanidin extracted from the red skin of peanuts.The macroporous adsorption resin X-5 have been selected to the adsorption,desorption and separation of the red pigment and procyanidin extracted from the red skin of peanuts.The optimum adsorption conditions were as follows:the rate of solid to solution was 25∶1,feeding rate 1.5 mL/min, pH 6.The optimum desorption conditions were as follows:feeding rate 2 mL/min,pH 5,the red pigment can be first desorbed and isolated with 95% ethanol solution and next the procyanidin with 70%.It was determined that the color value of red pigment is 38.2,and the content of procyanidin is 79.1%.3. Research has been carried out on the physical and chemical properties of red pigment and procyanidin from the red skin of peanuts.The stability of red pigment and procyanidin under different environments has been studied.The results show that:the red pigment and procyanidin has a great heat resistance,and it is stable to most reducing agent,food additives,preservatives and metal ions.It is stable for preservation in the environment.And the red pigment is more sensitive to light and oxidants,it should be kept away from light.But the procyanidin is very stable to light and oxidants. 4. Research has been carried out on the biological activity of red pigment and procyanidin from the red skin of peanuts.The scavenging activity of red pigment and procyanidin from the red skin of peanuts on hydroxyl free radicals,superoxide anion,alkyl radical and hydrogen peroxide were studied in this project.The results indicated that the red pigment and procyanidin from the red skin of peanuts have high scavenging activity.And with the comprehensive comparison we know that the procyanidin has a stronger antioxidant capacity than red pigment.