Factors Affecting Enzyme Activity

Function of Enzymes Enzymes in our digestive system are produced to change complex food particles into more simpler versions. This allows these particles to be easily absorbed by our bodies and used by our cells. Without enzymes, we would not be able to harness any of the nutrients from our food and we would starve!

Rate of Enzymes The activity of an enzyme is affected by its environmental condition. Changing these will alter the rate of reaction or how fast an enzyme will work. Our enzymes are designed to work specifically in the human body’s digestive system.

Temperature By increasing the temperature, enzymes will work faster. Our enzymes are designed to work at 37 degrees Celsius as the optimum temperature. Too cold and the enzyme reaction will slow down. Too hot and the enzyme will be ‘de-natured’ and will not work.

The temperature at which the maximum rate of reaction occurs is called the enzyme's  Optimum Temperature.

pH – Acids and Bases pH measures the Acidity and Basicity of a solution. It ranges from a pH of 1 (acids) to a pH of14 (bases).  Different enzymes have different Optimum pH values. This is the pH value at which it will work quickly and efficiently. Any change in pH above or below the Optimum will quickly cause a decrease in the rate of reaction

Small changes in pH above or below the Optimum do not cause a permanent change to the enzyme. However, extreme changes in pH can cause enzymes to Denature and permanently loose their function. For example, the enzyme Pepsin functions best at around pH2 and is found in the stomach, which contains Hydrochloric Acid (pH2).

Concentrations of Nutrients and Enzymes The more concentrated the nutrient (the higher the amount present in the digestion system) the faster the enzyme can work. This is because more nutrient particles will be interacting with enzyme particles. As more and more of the nutrient is changed by the enzyme, the slower the reaction will become. Eventually all enzymes will be working and therefore the rate will stop increasing. This also works the same way for the concentration of the enzyme itself.

Size of Particles The larger the size of the particles of the nutrients the harder the enzymes have to work. This slows down the breakdown and eventual absorption of the nutrients themselves. This is because the enzyme can only attach on the outside of the food particle and cannot easily penetrate the inside, taking longer to digest overall.