Study On Optimization Of Ultrasonic-assiated Extracion Technology And Antioxidant Activities Of Polyphenol From Noni Fruit And Leaf

Noni commonly called Morinda citrifolia L., a plant of the Rubiaceae family, is extensively cultivated in the near India ocean regions, such as Tahiti, Samoa, Australia, Hawaii and Southeast asia. Noni grows mainly in tropical and subtropical areas. In China, noni distributes mainly in Hainan, Yunnan and Taiwan province. Noni has the effects of anti-inflammatory, analgesia, antiviral, antioxidant, antiviral, its rich content of polyphenolic compounds, it is an ideal natural source of antioxidants. Hence, the main objectives of this study were to determine the significant process variables as well as the optimal conditions of ultrasonic-assisted extraction that would allow for the maximum extraction of polyphenols from noni using response surface methodology. The results showed as follows:In noni fruit and leaf, the research revealed a significant positive relationship between flavonoid content and polyphenol content, there was no significant difference between the total flavonoids and polyphenol content of noni fruit and ripe fruit. The content of flavonoids in different periods of noni leaf:90days>270days>30days>210days>150days>330days. The content of polyphenol in different periods of noni leaf:90days>270days>210days>150days>30days>330days. From the considering the plant growth and leaf utilization, picking ripe fruit is more appropriate, leaf grown270days was selected for the medicinal materials.The results showed that the optimum colorimetric conditions for noni fruit was determined as follows:at760nm by applying1.5mL Folin-Ciocalteu reagent and2mL20%Na2CO3at50℃for30min. The order of influent factor was Folin-Ciocalteu reagent> Na2CO3> temperature> time. And the content of polyphenols in noni leaf can be well calculated according to their colorimetric absorption at750nm by applying Folin-Ciocalteu reagent2mL and20%Na2CO32mL at55℃for30min. The order of influent factor was Na2CO3> Folin-Ciocalteu reagent> temperature> time.Based on the single factor experiments, the interactive effects of four crucial parameters, including ethanol concentration, ratio of solvent to material, extraction time and temperature, they were studied by central composite design and were assessed by response surface methodology (RSM). The optimal process parameters for total extraction of polyphenol from noni were as follows:ethanol concentration was53%,ratio of solvent to material was1:32, extraction time was33min, extraction temperature was50℃. The extraction rate of polyphenol from noni was6.19mg/g, Antioxidant Activities was149.36umol/L trolox equivalent. The Regression Model was TPCF=6.27-0.22X1+0.15X2+ 0.17X3-0.06X4+0.21X1X2+0.29X1X3+0.34X1X4+0.13X2X3+0.13X2X4-0.13X3X4-1.73X12-0.48X22-0.35X32-0.19X42。The process parameters for total extraction of polyphenol from noni were as follows: ethanol concentration was68%,extraction time was50min,extraction temperature was40℃.The extraction rate of polyphenol from noni was15.85mg/g,Antioxidant Activities was175.93μmol/L trolox equivalent.