Ethyl acetate, chloroform, methanol,
ethylene, n-hexane, gallic acid, sodium hydro-oxide,
dimethyl sulfoxide, acarbose, buffer solution, potassium sodium tartrate,
DNS (3,5-dinitrosalicylic acid), amylase (aspergillus), etc. were
used in the experiments. Majority of the reagents were purchased from
Sigma-Alrdich (Steinheim, Germany).