Lab Report

Report 4

I/ Amylase

Amylase, like other enzymes, works as a catalyst. All catalysts are enzymes, but not all enzymes are catalysts. A catalyst is a substance that causes a chemical reaction to break down other substances, but the catalyst does not become a part of the end product of that reaction. Amylase digests starch by catalyzing hydrolysis, which is splitting by the addition of a water molecule. Therefore starch plus water becomes maltose (which is equivalent to two joined glucose molecules)

In this experiment we tried to find out how amylase work and the best temperature for amylase to work out. To be specific we 1st noted 8 tubes as below

| 4C | RT | 50C | 100C |

| 4-S | 4-E | RT-s | RT-e | 50-s | 50-e | 100-s | 100-e |

After that we put 2ml prepared (TA pre-prepared it) amylase suspension from green bean sprouts into tubes with E mark (present enzyme) and placed 4c, 50c and 100c tubes respectively in ice, warm water and boiled water (control the temperature through an oven.

After 5 minutes we than added 4ml of starch suspension and keep that condition for another 10 minutes.

We than dropped 1 drop of Lugol solution into each tune and here is the result

Temperature | Marked tubes | Color observation |

| | Before lugol | After lugol |

4 | 4-s | White | purple-black |

| 4-e | Opaque white | purple-black |

RT(room temperature) | RT-s | White | purple-black |

| RT-e | Opaque white | Less black |

50 | 50-s | White | purple-black |

| 50-e | Opaque white | Little purple |

100 | 100-s | White | purple-black |

| 100-e | Opaque white | White |

Analysing the result we can see that only in the ‘e’ tubes did the color change that is because amylase had broken down starch which prevented the lugol from react with starch

The different color among the ‘e’ tubes is probably because of the change in temperature. The less black the less starch left to react with lugol. We can conclude that amylase break starch...