The Effects Of Ph Influence The Ability Of An Enzyme

The purpose of this experiment was to examine the effects of different types of enzymes on different substrates, and how pH influences the ability of enzymes to breakdown proteins. Starch and albumin were used as the substrate to test the enzymes amylase, pepsin, trypsin, and unknown enzyme T. Lugol’s solution was used to test for the presence of undigested starch, while Biuret solution and Ninhydrin solution were used to test for the presence of undigested protein and amino acids respectively. There were many key findings in this experiment, one of which is that amylase was able to digest starch at all pH conditions, as it showed a gold colour, while pepsin, trypsin and the unknown enzyme T still had the presence of starch, as it showed a dark blue colour using Lugol’s solution. …show more content…
Amylase and the unknown enzyme T showed a violet colour using the Biuret solution under all pH conditions, indicating that there were still protein that was undigested. Pepsin and Trypsin however, was able to digest the protein into its polypeptides, as it showed a pink stain under the Biuret solution, the latter only showing signs of breakdown after 20 minutes. Lastly, under the Ninhydrin test, pepsin and unknown enzyme T was able to completely breakdown the protein, as the filter paper was stained purple, indicating the presence of amino acids. Amylase and trypsin did not breakdown albumin as there were no signs of colour on the filter paper. The results indicate that the unknown enzyme T was able to breakdown the protein into amino acids, as shown by the colour change in the Ninhydrin test. Amylase tested positive after a significant amount of time because the proteins may have broken down over time due to the heat from the