Study on extraction conditions and free radical scavenging activity of polysaccharides from persimmon leaves
Persimmon leaf, coming from Diospyros kaki, may be associated with potential health benefits due to its functional components such as polysaccharides, polyphenols, terpenoids, carotenoids, organic acid and vitamin C. Persimmon leaf polysaccharides (PLP) have hypoglycemic, antioxidants and other properties. The activities of phyto-polysaccharides depend on the source, extraction and purification methods. The aim of this work was to study the effects of water extraction conditions on the extraction rate, resulting components, and the activity of scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical of PLPs. We found that the extraction rate of PLP, the content of neutral sugars and uronic acids and the activity of scavenging DPPH radical of PLP were all affected significantly by the pH of the extract, temperature, time, and the ration of solid-liquid obtained. The extraction rate of PLP increased with the increasing of the following factors: temperature, reaction time, proportion of water/PLP and pH of solution. In order to get the maximum extraction rate and activity of PLP, the optimum extraction parameters were: and pH of 12 at 70°C for 1.5 h with a ratio of PLP/water of 1:20 (g mL-1). With these conditions a yield of PLP 6.2% is reached and a relative high activity of scavenging DPPH radical is obtained.
Chen, Y.Q., Zhang, J.D., Ni, D.J. and Hao, Q.Q. (2018). Study on extraction conditions and free radical scavenging activity of polysaccharides from persimmon leaves. Acta Hortic. 1195, 219-224
persimmon leaf, polysaccharides, extraction, antioxidants