Study On Extraction, Purification And Structure Identification Of Anthocyanins From Sunflower Seed Hull

Xin Kui NO.8 Oil-sunflower is an important oil crops resource,The seed hull is an good resource for the development of natural pigment due to rich nature anthocyanins. In order to improve the yield and quality of anthocyanins, and actualize the reuse of sunflower seed hull(SSH),Comparative analysis of the extraction process parameters with acidified ethanol, Ultrasonic wave assisted acidified ethanol were optimized,The characterization of the sunflower seed hull anthocyanins (SSHA)were investigated,The composition and structure of SSHA were analyzed and identified.The main results showed as follows:With hydrochloric acidified ethanol as reagent, the optimum process parameters of pH 2, Temperature 54℃,ratio of liquid to material 22:1, and time 112min were obtained for antho-cyanins extraction from SSH by good single factor selecting and Response Surface Methodo-logy (RSM).The maximum predicted anthocyanins yield was 663.03mg/100g,but actual anthocyanins yield 661.74 mg/100 g. With the extraction method of ultrasonic wave assisted hydrochloric acidified ethanol, a maximum predicted extraction yield of 757.01mg/100 g, actual anthocyanins yield 755.91mg/100g,was obtained under pH 2, ratio of liquid to material 20:1, temperature 53℃, time 56 min,ultrasonic wave power of 360W. Compared to the former extraction method, the extraction method dramatically reduced extraction time,and the extraction yield of anthocyanins increased, but the color value slightly reduced.Through comparisons among four kinds of resins' adsorption,desorption property, HPD-400 resin was selected as a preferable resins with the adsorption equilibrium rate constant of 0.0619/min and the equation fits the Langmuir equation well. The maximum adsorption quantity was at 18.62mg/g,temperature 30℃. And the purification conditions were studied by good single factor selecting.The optimal adsorption conditions were concentration 0.283mg/ml,pH2.0 and velocity 4.0ml/min.The optimal desorption conditions were 50% ethanol, pH3.0 and velocity 3.Oml/min.The pigment produced by this technological process was purplish dark power.And the color value was neraly 2 times higher than that of pigment without purification.The pigment in SSH is water and alcohol soluble.In acidic solution,the ebb light,the stability of the pigment was good. Al3+,Pb2+,Fe3+,Sn2+ evidently degraded the pigment,but K+,Zn2+,Mg2+,Ca2+had no harmful effects on it. In the frequently used food additive,Sucrose, glucose possess effect of pigment protection, Vc had no negative effects on it,but the absorbance of the pigment were reduced by sodium benzoate. Oxidant and reducing reagent enhanced the fading of pigment.SSHA were analysised by the way of paper chromatography(PC),ultraviolet-visible spectrum(UV),Acid hydrolysis and high pressure liquid chromatography-mass spectrometry (LC-MS), the types of anthocyanin and varieties of sugar had come to conclusion. The result showed that the pigment consisted of three components that were Pelargonidin-3-O-glu-Chloride, Cyanidin-3-O-glu-chloride and Peonidin-3-O-glu-chloride.