The solid and liquid materials were separated into filtrate and precipitate by filtration with a filter paper (ADVANTEC,No. 131), and the filtrate (water extractive) was dried at 105 _C for 24 h and weighed. The water-soluble sugars in the filtrate were converted to monosaccharides by treatment with 4%(w/v) sulfuric acid (H2SO4) at 121 _C for 30 min and the reaction mixture was analyzed by high performance liquid chromatography (HPLC) using an aminex column HPX-87H (300 _ 7.8 mm, Bio-rad, Richmond, CA, USA) (Davis et al., 2006).