Total soluble protein of the homogenate was measured using folin–phenol reagent (Lowry et al., 1951). Amylase activity was measured by 3,5-dinitrosalicylic acid (DNS) method (Rick and Stegbauer, 1974). The reaction mixture consisted 0.1 mL of 1% (w/v) starch solution as substrate, 1.8 mL phosphate buffer (0.1 M, pH 7) and 0.1 mL tissue homogenate. The mixture was incubated at 37 °C for 30 min. The reaction was stopped by adding 2 mL DNS reagent, and kept in boiling water bath for 5 min. The reaction mixture was diluted with distilled water and recorded the absorbance at 540 nm. Activity was determined
from the maltose standard curve and expressed as mole of maltose released from starch mg−1 protein min−1 at 37 °C.