Title: Investigation of the amalyse activity f bioactive washing powder Objective: To investigate the amalyse activity of the two brands of bioactive washing powder – “Super clean” and “Magic power”. Principal: Amalyse can catalyse the breakdown of starch into maltose. In this practical, solutions of the 2 washing powders will be filled into 2 identical wells on the starch agar plate separately. Starch will be broken down by the amylase disused to the star-agar. A clean zone will be formed around the wells when iodine solution is added and flushed.
The higher the amylase activity, the more the starch will be broken down. Hence, a larger and clearer zone will be observed. Thus the diameter of the clear zone can show the activity of the amylase. In this experiment, the independent variable is the types of washing powder in the solution. The dependent variable is the diameter of clear zone on agar plate. The controlled variables are the concentration and volume of washing powder solution added into well, size of the wells, temperature of incubator and time for agar plate in incubator.
Apparatus and materials: Apparatus: 3 droppers, 3 test tubes, an electronic balance, 3 labels, cork borer, incubator (37’C), a ruler, 2spatulas Materials: 1 gram of “Super clean” and “Magic power” washing powder, distilled water, iodine solution, a starch agar plate Procedure: i. Drill 3 identical wells on the starch agar plate by a cork borer ii. Weigh 1 gram of “Super clean” and “Magic power” washing powder separately using the electronic balance.
iii. Dissolve the measured washing powders with 4mL distilled water in 2 test tubes respectively.. iv. Labeled the wells on the underside of the dish of agar plate using the following codes: A: “Super clean” solution B: “Magic power” solution C: Distilled water v. Add 2 drops of “Super clean” solution, 2 drop of “Magic power solution” and 2 drop of distilled water into their corresponding wells vi. The agar plate is then put into the incubator (37’C) for 24 hours.
vii. Flood the pate with iodine solution for about 30 seconds. The flush the iodine solution away carefully with tap water. viii. Observe the starch-agar plate against a white background. Compare the colour within and around the wells Measure and record the size of clear zones. Precautions: 1. Wells must be well spaced and mapped 2. Avoid exposure of starch agar plate to non-powder source of amalyse i. e. cover the plate after dropping the solution immediately and avoid talking during the task
