AMYLASE

• RATE OF REACTION ON AMYLASE:

  AIM

  To determine the rate of the amylase activity at different pHs.
• RATE OF REACTION ON AMYLASE:

  METHOD

  • You will investigate the breakdown of starch by amylase at different pHs.
  • The different pHs under investigation will be produced using buffer solutions (produce a particular pH, and will maintain despite addition of other substances).
  • The amylase will break down the starch.
  • A series of test tubes containing a mixture of starch and amylase is set up at different pHs.
• RATE OF REACTION ON AMYLASE:

  METHOD

  • A sample is removed from the test tubes every 10 seconds to test for the presence of starch. 
  • Iodine solution will turn a blue/black colour when starch is present.
  • When all the starch is broken down, a blue-black colour is no longer produced. The iodine solution will remain orange-brown.
• RATE OF REACTION ON AMYLASE:

  METHOD

  • A control experiment must be set up - without the amylase - to make sure that the starch would not break down anyway, in its absence.
  • The result of the control experiment must be negative - the colour must remain blue-black - for results with the enzyme to be valid.
• RATE OF REACTION ON AMYLASE:

  METHOD

  When the starch solution is added:

  • start timing immediately
  • remove a sample immediately, and test it with iodine solution
  • sample the starch-amylase mixture continuously, every 10 seconds

  For each pH investigated, record the time taken for the disappearance of starch (when the iodine solution in the spotting tile remains orange-brown)

  Hazards

  • Wear safety goggles.
  • Amylase solution may cause allergic reactions.
  • Iodine solution is irritant. Avoid contact with skin and eyes.