Study On Optimization Of Extracting Polysaccharide From Aronia Melanocarpa And Its Antioxidant Activity

The fruit of aronia melanocarpa is rich in nutrients including a variety of vitamins,minerals,polysaccharides and polyphenols,with anti-inflammatory,anti-atherosclerosis,anti-bacterial,anti-tumor,anti-diabetes,anti-aging and immune enhancement effects,currently,relevant health juices and medicines have been developed.As one of the functional components in plants,and with a variety of biological activities,plant polysaccharides have also been researched and developed and widely used in the food,health and pharmaceutical industries.In this study,three extraction methods were selected to extract the polysaccharide from aronia melanocarpa:hot water extraction,ultrasonic extraction and cellulase extraction.By response surface analysis,the optimum technological parameters of each method were selected,and the yield of crude polysaccharide under these optimum extraction conditions was compared.In addition,the paper also studied the decolorization,protein removal,separation and purification,monosaccharide composition analysis,and antioxidant activity in vivo of the polysaccharide of aronia melanocarpa.The research results are as follows:1.Study on extraction method of crude polysaccharide from Aronia melanocarpaThe optimal process of hot water extraction: through single factor tests of time,temperature and material liquid ratio,the yield of crude polysaccharide was analyzed then The optimum extraction conditions were as follows: time 90 min,temperature77 ℃,solid-liquid ratio 1:40.Under these conditions,the yield of crude polysaccharide was 3.26%.The optimal process of ultrasonic extraction: the single factor tests of solid-liquid ratio,power and time were carried out,detection of crude polysaccharide yield,then the response surface optimization test was carried out and the optimal test condition was determined to be: the ratio of material to liquid 1:30,power 330 w,and time 63 min.Under this condition,the yield of crude polysaccharide was 5.60%.The optimum process of cellulase extraction: the single factor tests of p H,enzyme quantity,time and temperature were carried out,detection of crude polysaccharide yield,then the response surface optimization test was carried out andthe optimal test condition was determined to be:p H 5,enzyme amount 2%,time 100 min,temperature 53℃.Under this condition,the yield of crude polysaccharide was4.08%.2.Separation and purification of polysaccharide from Aronia melanocarpaOptimal decolorization process of activated carbon: through single factor test of activated carbon amount,time,temperature,the changes of decoloration rate and polysaccharide retention rate under various conditions were recorde.The orthogonal test optimization was adopted,and the best decoloration conditions were determined according to the comprehensive score: activated carbon amount 1.5%,time40 min,temperature 40℃.Under this condition,the decoloration rate was 74.5%,and the retention rate of polysaccharide was 85.03%.The total sugar content of polysaccharide obtained after separation and purification is 55.3%.3.Analysis of monosaccharide composition and antioxidant activity of polysaccharide from Aronia melanocarpaThe monosaccharide composition of Aronia melanocarpa polysaccharide was analyzed by GC-MS.Aronia melanocarpa polysaccharide was mainly composed of arabinose,D-mannose,L-glucose and rhamnose with a molar ratio of5.44:1:3.56:18.56.In order to investigate whether the polysaccharide of aronia melanocarpa has antioxidant capacity,this paper used mice in vivo tests to observe the effect of aronia melanocarpa polysaccharide on acute liver injury model induced by ethanol in mice.The antioxidant activity of aronia melanocarpa polysaccharide was determined by measuring CAT activity,GSH-PX activity,SOD activity and MDA content in liver.The results showed that aronia melanocarpa polysaccharide has certain antioxidant capacity.