were dried at 75оC for 18 h in a hot air oven. The dried GS (23 g) were ground into fine powder and 19 g was extracted with ethanol/water (3:2, v/v) at 60оC for 24 h at an extraction ratio of 15. The extraction was repeated 3 times in the same manner. The insoluble materials were removed by filtration. Crude GSE(2.6 g) was obtained by lyophilizing the extracted solution after removing the ethanol under reduced pressure at 60-
70оC.