Study On The Content And Composition Of Polysaccharides In Different Harvest Stage

This paper research wolfberry fruit from blossom to ripe,which planted near the Helan Mountain, recording growth and development of fruit morphological changes, determination of polysaccharides of different maturity,studying different stages of growth and harvest polysaccharide monosaccharide composition, shear rate dependency of viscosity of Lycium barbarum polysaccharide(LBP), activity of polysaccharide in scavenging OH-, superoxide anion,DPPH-,ABTs, concluded as following:This study measure and record morphological changes in the development of wolfberry fruit,determination of Polysaccharide Content in wolfberry fruit with3,5-dinitrosalicylic acid method. Wolfberry fruit growth and development is divided into two rapid growth and a slow growth period.The first time of rapid growth is from the first day to ninth day.At this time fruit shape and size development rapidly,and the color was white and green. Fruit morphological development is slow from the 10 d to the 24 d.Its overall color is light green and fruit base begin to turn yellow. Fruit grow very rapidly from the 25d to 34d. In this case the base of the fruit color from green gradually begin to yellow and then quickly turned bright red. Summer fruit’s morphological index is better than autumn fruit and the ordinary summer fruit is better than first fruit crop. In wolfberry fruit growth and development process the polysaccharide content was increasing trend. Maturity reached about 1.5% of the total weight of fresh fruit. Autumn fruit polysaccharide content accounted for 1.23% of the total weight of fresh fruit.The ordinary summer fruit polysaccharide content accounted for 1.48% of the total weight of the fruit. The first crop Chinese wolfberry fruit polysaccharide content accounted for 1.52% of the total weight.We dried different maturity wolfberry with hot air, extracting polysaccharides by water extraction and alcohol precipitation, deproteinizing by Sevag method, using TOYOPEARL DEAE-650M ion-exchange column for purification. Anthrone-sulfuric acid method was used to determine the content of LBP.The results showed that before deproteinization different mature fruit polysaccharide content accounted for dried fruit weight ratio were 3.96%,5.87%,4.52%,4.13%, 3.83%. After deproteinization different mature fruit polysaccharide content accounted for dried fruit weight ratio were 3.04%,4.39%,3.77%,3.51%,3.25%. Different mature fruit polysaccharide loss rate of 23.23%,25.21%,16.59%,15.01%,15.14% after the removal of protein. The polysaccharide were hydrolyzed into monosaccharides with TFA. The monosaccharide derivatives obtained with 1-Phenyl-3-methyl-5-pyrazolone (PMP) were separated by HPLC using a gradient elution process. The monosaccharide compositions in polysaccharides of wolfberry from different growth stages were significantly different,but all polysaccharides were composed of mannose, rhamnose, galacturonic acid, glucose,galactose, xylose, and arabinose. The gree stage of LBP was mainly composed of galactose and arabinose. The color changing stage of LBP was mainly composed of galacturonic acid, glucose and arabinose. The ripe stage of LBP was mainly composed of galacturonic acid, glucose, galactose and arabinose.LBP have different characteristics in different developing and harvest stages. There are significant differences in rheological properties of Chinese wolfberry in different mature stages. Before deproteinization viscosity were:0.0132Pa·s,0.0117Pa·s,0.0121Pa·s,0.0119Pa·s,0.0116Pa·s. After deproteinization viscosity were:0.961Pa·s,1.108Pa·s,1.330Pa·s,1.289Pa·s,1.197Pa·s. Viscosity after purification were:1.02Pa·s,1.26 Pa·s,1.53 Pa·s,1.49 Pa·s,1.37Pa·s. This paper studies different maturity LBP on different concentrations in vitro antioxidant activity and measures activity of polysaccharide in scavenging OH-, superoxide anion,DPPH-,ABTs. Polysaccharide clearing radical activity increases with the concentration. Compared the same concentrations but different growth stages of polysaccharide activity that get conclusion:the green stage<the color changing stage<the ripe stage. Compared the same concentration but different harvest stages of polysaccharide activity that get conclusion:the first fruit crop> the ordinary summer fruit> the autumn fruit.