Lyven protocol For each erlen: following of starch hydrolyze Removal of 0.5 ml of starch solution Adding 2.5 ml iodine reagent Mixing by reversal Read optical density at 630 nm At the beginning starch is blue dark. Then it turns to brown when it is transformed in dextrin with amylase activity. At the end of hydrolyze the solution stay yellow Composition

Time of hydrolyze with amylase Starch Dextrin Time of hydrolyze with amylase

Iodine reagent Iodine concentrated solution: Iodine reagent: Return Iodine concentrated solution: 4.4 g of potassium iodure (KI) 2.2 g of iodine (I2) Dissolve successively in about 20 ml of distilled water, complete to 100 ml Store this solution in dark glass maximum one month Iodine reagent: Dissolve 4g of potassium iodure in about 80 ml of distillated water Add 0.4 ml of iodine concentrated solution Complete to 100 ml with distilled water Store maximum one day Individual protection equipment is recommended for iodine handling