Effect of Drying Temperature on Phenolic Contents and Its Antioxidant Activity of Phyllanthus emblica L.

In order to explore the effect of drying method(vacuum freeze and hot air drying)and drying temperature(freeze drying,40,60,80,100 ℃)on the phenolic ingredients in Phyllanthus emblica L.(P. emblica),the high performance liquid chromatography(HPLC)was used to analyze the content of four phenolic compounds,gallic acid,corilagin,ellagic acid and chebulagic acid,in the P.emblica dried at different treatment. And the total polyphenol content and antioxidant activity(ABTS⁺· and DPPH· scavenging ability)of each sample were investigated. The results showed that the contents of four compounds increased with the drying temperature,which reached the highest point at 100 ℃(12.83,6.04,16.89,13.48 mg/g). Apart from this,the total phenolic contents,ABTS⁺· and DPPH· scavenging increased with the temperature and activity peaked at 200.92,695.76,725.05 mg/g under 80 ℃. Meanwhile,there were significantly or extremly significantly(P<0.05 or P<0.01)positive correlations among phenolic compounds(corilagin,chebulagic acid),total phenolic,and the ABTS⁺free radical scavenging activity. In this test,compared with hot air drying,the vacuum freeze did not show the obvious advantage in the content of four phenolic compounds and total polyphenol,and the antioxidant activity. Considering comprehensively,it was suggested that 80 ℃ hot air drying should be the optimum drying method for P. emblica.