The pH and clear zone diameter of each sample extracted in distilled water was determined. Almost all samples showed acidic ph of 4.0 – 6.0, except for carrot (pH 7.0). the samples were then characterized for amylase activity. The amylolytic activity was detected using the method described above. The reaction can be detected after 30 min, which gives the highest clear zone diameter (data not show). All samples showed amylolytic activity; the 5 highest activity crude extracts were pomelo, orange, yard long bean, cabbage and morning glory, respectively.