Each enzyme work bests at a specific pH value. The optimum pH for an enzyme depends on where it normally works. For example, enzymes in the small intestine have an optimum pH of about 7.5, but stomach enzymes have an optimum pH of about 2.

Conclusions: The rate of a chemical reaction increases as the substrate concentration increases. Enzymes can greatly speed up the rate of a reaction. However, enzymes become saturated when the substrate concentration is high.

The substrate is limiting. The higher the substrate concentration, the faster the reaction. This is because more substrate molecules means a collision between substrate and enzyme is more likely and so more active sites will be used.

If the concentration of the enzyme or substrate is increased, the rate of the reaction will be increased as well. If the temperature of the enzymes surrounding environment is increased, then the rate of the reaction will also be increased. The dependent variable is the rate of the reaction.

Enzyme activity is generally greatest when substrate concentration is unlimiting. A reaction is most likely to be zero order initially since substrate concentration is then highest. To be certain that a reaction is zero order, multiple measurements of product (or substrate) concentration must be made.

Optimization of enzyme concentration and timing in HAT assays. Optimal enzyme concentration and assay timing can be determined by a straightforward time-course experiment combined with enzyme titrations. In an ideal assay, HAT activity should be measured during the linear phase of the reaction.

We can conclude that each enzyme in metabolism has to be optimized according to its specific environmental conditions, and so, the recognition of an optimized state in an enzyme requires the knowledge of concentration range of its reactant under which the enzyme usually functions; a detailed study of these …

The next phase of the HTS process involves the miniaturization of the chosen assay to 96-well or, preferably, 384-well formats. During the assay optimization phase, it is expected that the investigator has detailed understanding of a variety of parameters for their assay. …

8.6 to 9.0

37.5 oC

Using a spectrophotometer to measure the output of NADH over a two-minute period within 3 pH levels (10.5, 8.8, and 6.5), it was found that the pH closest to physiological pH yielded the most efficient output of NADH by yeast ADH, and that the acidic pH level degraded enzyme activity more severely than the basic pH …

Some enzymes require the addition of another non-protein molecule to function as an enzyme. These are known as cofactors, and without these enzymes remain within the inactive “apoenzyme” forms. Once the cofactor is added, the enzyme becomes the active “holoenzyme”.

How to Prevent Enzymatic Browning

• Cold water: Simply by placing peeled potatoes in cold water can prevent the browning. This only works with cold water.
• Blanching: This is the process of a short heat treatment to the fruit or vegetable in order to destroy or inactivate enzymes.

The method that retains the most antioxidants when cooking vegetables is stir-frying. When you stir-fry, you use a small amount of oil to cook the veggies on high heat for a short period of time. Heat itself isn’t the enemy, but rather how long the food is exposed to heat.

Drying removes the moisture from food so that microorganisms such as bacteria, yeasts, and molds are less likely to grow; however, drying does not effectively destroy them. Low humidity is also needed when drying foods.