The activities of - and -amylase were assayed using Amylase HR reagent and Betamyl®, respectively, as substrates (Megazyme International Ireland Ltd., Bray, Ireland). To determine -amylase activity, 0.1 ml of a five-fold diluted enzyme extract was mixed with 0.1 ml of Amylase HR reagent and incubated for 30 min at 40ºC in a water bath.To determine -amylase activity, 0.1 ml of the undiluted enzyme extract was incubated with 0.1 ml Betamyl® for 1 h at 40ºC. The enzyme reactions were stopped by adding 1.5 ml of 1% (w/v) Trizma base (SIGMA-Aldrich). Two blanks were included in theenzyme assays, replacing the enzyme extract with extraction medium or replacing the substrate with water. A standard curve of -nitrophenol (PNP; SIGMAAldrich) dissolved in 1% (w/v) Trizma base was prepared. The absorbance of the PNP standards, and each stopped enzyme reaction,was measured at 400 nm. The activities of both - and -amylase were expressed in nmol PNP g–1 DW min–1.The linearity of each enzyme activity,compared to the amount of enzyme and the time of incubation,was checked