Effect Of Polysaccharide And Flavornoid On The Regulation Of Lipid Metabolism And Intestinal Flora Proliferation

With the improvement of people's living standards and the change of lifestyle,cardiovascular and cerebrovascular diseases have become a typical representative of modern chronic diseases.Hyperlipidemia is one of the major chronic diseases.The occurrence and development of hyperlipidemia are closely related to disorders of excess free radicals,lipid metabolism and imbalance of intestinal flora.Natural product extracts has many kinds of pharmacological effects,and is safe and has few side effects,because it contains biological active ingredients.In this paper,Auricularia auricular,tremella fuciformis and hawthorn were used as raw materials.The raw materials were pretreated by liquid nitrogen freezing pulverization technology.Then combined with ultrasonic assisted hot water extraction to optimize the extraction process of auricularia auricular polysaccharide and tremella fuciformis polysaccharide,ultrasonic assisted ethanol extraction to optimize the extraction process of flavonoid from hawthorn,and the monosaccharide composition of auricularia auricular polysaccharide and tremella auriculata polysaccharide was analyzed;Wistar rats were selected to create hyperlipidemia model and treated with auricularia auricular polysaccharide,tremella fuciformis polysaccharide,hawthorn flavonoid and polysaccharide flavonoid compounds to study the effect of polysaccharide and flavonoid extracts on rat lipid metabolism;The effects of polysaccharide flavonoid compounds on intestinal flora of rats were studied by high-throughput sequencing.From the analysis,the following conclusions are obtained:(1)The powder particle size is uniform and smaller by using liquid nitrogen freezing comminution,which is beneficial to the better dissolution of polysaccharide.According to the crushing screening and the detection of laser particle size distribution instrument,it can be known that conventional pulverization of particles above 120 mesh only accounts for 39.5%,while liquid nitrogen freeze pulverization accounts for 67.5%.(2)Ultrasound assisted extraction of polysaccharide and flavonoid.The optimal technological parameters of polysaccharide from Auricularia auricular were determined to be ultrasonic temperature 60 ?,ultrasonic time 8 min,material-liquid ratio 1:50,and the average extraction rate of crude polysaccharide from Auricularia auricular was 13.3%;The optimal extraction process for Tremella fuciformis polysaccharide was determined as follows: ultrasonic temperature 63 ?,ultrasonic time 53.70 min,material-liquid ratio 1:73,and the maximum extraction rate of Tremella fuciformis polysaccharide was 18.92%.Theoptimal extraction process of flavonoid in hawthorn was determined as follows: ultrasonic temperature 50 ?,ethanol concentration 70%,material-liquid ratio 1:40,and the average extraction rate of flavonoid in hawthorn was 9.26%.(3)The monosaccharide compositions of auricularia auricular polysaccharide and tremella fuciformis polysaccharide were analyzed by PMP pre-column derivation high performance liquid method.The monosaccharide composition and proportion of auricularia auricular polysaccharide were as follows: mannose: glucuronic acid: glucose:galactose: xylose: fucose(8.64:1.00:13.47:1.69:2.13).The monosaccharide composition and ratio of tremella fuciformis polysaccharide are as follows: mannose: glucuronic acid:glucose: xylose: fucose(10.86:1.00:5.89:5.59:6.68).(4)The compound of polysaccharide and flavonoid assisted in the evaluation of hypolipidemic and antioxidant.Auricularia auricular polysaccharide,tremella fuciformis polysaccharide,hawthorn flavonoid and low,medium and high dose compounds can reduce serum TC and TG in hyperlipidemia rats.The content of HDL-C in the high dose compound group(0.63±0.10 mmol/L)was significantly higher than that in the model group(0.45±0.10 mmol/L)(P<0.05),the content of LDL-C in the medium dose compound group(0.33±0.07 mmol/L)and the high dose compound group(0.31±0.03 mmol/L)was significantly lower than that in the model group(0.42±0.08 mmol/L)(P<0.05),and the high dose compound group significantly reduced the risk of atherosclerosis.The activity of SOD and GSH-Px in the serum,brain and liver tissues of rats in the low,medium and high dose compound group increased compared with the model group,and the MDA content decreased.(5)The compound of polysaccharide and flavonoid help protect the liver.Compared with the model group,the AST and ALT enzyme activities in the serum of rats in the low,medium and high dose compound groups were significantly reduced(P<0.05),while there was no significant difference in the two corresponding indexes of the rats in the tremella fuciformis polysaccharide group and hawthorn flavonoid group(P>0.05),The results showed that the combined action of auricularia auricular polysaccharide,tremella fuciformis polysaccharide and hawthorn flavonoid had protective effect on liver;Compared with the model group,the liver coefficient of the high dose compound group was significantly reduced(P<0.05).According to the histomorphological analysis of rat liver,the fat vacuoles were significantly reduced in the middle and high dose compound groups,and the arrangement of liver cord cells was orderly,which effectively improvedthe liver tissue status.(6)The compound of polysaccharide and flavonoid regulate positively on intestinal flora.In the hyperlipidemia model group,the intestinal flora structure of the rats was maladjusted,in which the number of harmful bacteria such as Escherichia coli/Shigella,Helicobacter,?-proteobacteria,Burkholderia,Clostridium,Coprococcus was increased,while the relative abundance of beneficial bacteria such as Bifidobacterium and Lactobacillus was decreased.The high dose compound group inhibited the reproduction of harmful bacteria such as Escherichia-coli/Shigella and Clostridium and promoted the growth of beneficial bacteria such as Lactobacillus,Bifidobacterium,and Lactobacillus acidophilus.In summary,the application of liquid nitrogen freezing crushing combined with ultrasonic assisted extraction technology can achieve a good extraction effect of polysaccharide and flavonoid,and the combination of polysaccharide and flavonoid can achieve a good lowering of blood lipid,anti-oxidation and protection of the liver,as well as a good positive regulation of intestinal flora.This study will lay a theoretical foundation for the future development of functional foods of polysaccharide and flavonoid.