In beaker 2 containing bile, the pH decreased the quickest. The bile increased the rate of reaction by the lipase enzymes because it emulsified the triglycerides and broke them down into smaller bits, therefore increasing the surface area. There were more points of contact for the enzymes to bind with the substrate, and so products were formed at a faster rate.
Beaker 3 was used as a control to show that the enzyme lipase acts upon the trigylcreides and breaks them down to fatty acids, which decreases the pH. In beaker 3 the boiled lipase enzymes are denatured, and so cannot react with the substrate to form products, so the pH remains constant.
Both beaker 1 and 2 level off towards the end, this is either because all of the substrate has been used up and the lipase enzymes cannot make any more products, or the pH has decreased so much so, that the enzymes cannot work. The pH may be too acidic for the enzymes and so they are denatured.
Temperature was not maintained during the experiment, this may have had an affect on the rate of reaction because the enzymes have their own optimum temperature. The temperature may have fluctuated during the experiment, at higher temperatures the rate of reaction would be increased because the enzyme and substrate would have more kinetic energy, and so they would collide and form more products. The temperature could be maintained using a thermostatically controlled water bath.
For Obtrusive jaundice sufferers, bile is not released intro the duodenum, so therefore the patient would not be as affective at digesting and breaking down fats. The trigylcerides would not be broken down as fast, because the bile is not present to increase the surface area, less fats would be broken down and absorbed into the bloodstream.
