Study Of Antioxidant And Anti-aging Activity Of Polyphenol Compounds In Mulberry

Polyphenols are a class of compounds in widespread. Most polyphenols were found in plant. So far, there are reported more than 8000 kinds of plant phenolic compounds, and every year there are still a lot of new phenolic compounds have been found. These phenolic compounds most have antioxidant, anti-mutagenesis, antitumor activity, reduce the risk of cardiovascular disease and so on. According to the report of the national disease detection system, the charts mortality of cardiovascular disease in our country is the greatest threat to the elderly population health in modern society, and aging is the main cause of cardiovascular disease. Polyphenols is one of the important antioxidant active ingredients of mulberry, and the content is rich. Therefore, the development of mulberry polyphenols has important theory value and research significance. This study started from the selection of mulberry varieties, choose DA 10, TANG 10 and Tai SANG of mulberry five different mature stage are polyphenol extraction and antioxidant activity of the research, then different drying technology is suitable for mulberry extract polyphenols and antioxidant activity of the research, and choose suitable drying technology, based on the simple efficient extraction of mulberry polyphenols technology, and its anti-aging effects on aging mice, for research and development has the medical and health care efficacy of mulberry polyphenols products to provide technical support. The main research results are as follows:(1) The effect of different varieties in different mature stages on mulberry polyphenols content and antioxidant activity: selected DA 10, TANG 10 and Tai SANG three varieties of mulberry in five mature stages, the experiments of mulberry measure include chromaticity, soluble solid solution material content, the value of p H, titratable acid, free phenol contents, bound phenol content, flavonoids content and evaluated the ability of scavenging DPPH radical, the FRAP antioxidant capacity and the ORAC antioxidant capacity of mulberry phenols. Results show that the mulberry soluble solid solution with the passage of mature process content of s-shaped growth trend, titratable acid showed a trend of first of lowered later, p H has a downward trend. With the passage of mulberry mature process, the phenolics changing, mulberry phenolic compounds are present s-shaped increasing trend, reached the maximum at maturity; The content of flavonoids of change is not obvious. Through the polyphenol content and three kinds of antioxidant activity to do correlation analysis between strong and weak, polyphenol content and antioxidant activity is stronger positive correlation. Through the experimental research, determine the pond 10 varieties of fully mature mulberry is suitable for this topic research of other content.(2) Fresh mature mulberry fruit which was used as experimental material, was taken on four kinds of drying methods, such as freeze drying(FD), vacuum drying(VD), hot air drying(HA)and heat pump drying(HP), with four kinds of temperatures(45℃, 50℃, 55℃ and 60℃) processing. Then, we analyzed the changes of color, free phenols content, bound phenols content, total phenols content, and total flavonoids content, and evaluated the ability of scavenging DPPH radical, the FRAP antioxidant capacity and the ORAC antioxidant capacity of mulberry phenols. Results indicated that compared with the fresh mulberry, the mulberry which have been processed with four kinds of drying methods had significant changes in chromaticity(ΔE*>9), the higher the temperature, the more obvious of the color change(P<0.05). After different drying process, the contents of mulberry free phenols, bound phenols, total phenols combined with total flavonoids had significant differences(P<0.05), and the drying temperature was the most important factor on the change of bound phenols and total flavonoids. There was a significant correlation between the ability of scavenging DPPH radical, the FRAP antioxidant capacity, ORAC antioxidant capacity and the phenol contents. Considering chromaticity, phenol contents and other factors, such as energy consumption, recommend low temperature such as 45℃ during the drying process of mulberry. It was conducive to protect the mulberry color and luster, and reduced the loss of active phenolic substances in mulberry.(3) Polyphenols are one of the important components of the antioxidant activity from mulberry fruit. Mulberry extract polyphenols can establish efficient and easy technology for research and development mulberry polyphenol products with the medical and health benefits to provide technical support. Mulberry fruit was used as experimental materials, using ultrasonic-assisted extraction of polyphenols by ethanol extraction method. On the basis of single-factor experiments, the effect of ethanol concentration, extraction p H value, mass concentration of raw materials, ultrasonic power and extraction time on the extraction yield of polyphenols from Mulberry fruit were optimized by response surface methodology. Use Design-Expert software for data regression analysis combined with validation tests to determine the process optimization of ultrasonic-assisted extraction of polyphenols from Mulberry fruit: ethanol concentration is 60.0%, p H value is 5.0, mass raw material concentration is 0.025g?m L-1, the ultrasonic power is 405 W, extraction time is 30 min, this condition mulberry fruit ultrasonic-assisted actual yield of polyphenols is 3.016%, predictive value is 3.161%, these two value is basically in line. The result indicated that the established model could be used to predict the extraction yield of polyphenols from mulberry fruit, and the process optimization extraction of conditions has practical value.(4) The study of Mulberry polyphenols affected the aging model mice induced by D-galactose. Using neck back 10% D-galactose subcutaneously in mice aging model was established, which looked at the little mouse, mulberry polyphenols extract liver, heart and blood serum malondialdehyde(MDA) content, catalase(CAT), total superoxide dismutase(T-SOD), the influence of the activity of monoamine oxidase(MAO). Determination results show that compared with model group, mulberry polyphenols extract can reduce the mice of MDA content in serum, liver, brain and heart, improve the mice serum, liver, brain and heart of the T- SOD activity, and improve the activity of CAT in serum, liver and heart, reduce the liver and brain MAO activity. The results show that the mulberry polyphenols extract has remove free radicals, antioxidant effect, improve the aging mice show some anti-aging effect.