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Catechol Oxidase Essay

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The marketing and storage of perishable foodstuffs can be delayed by using treating them with methods that will slow or halt enzymatic activity. We experimented as to whether or not varied concentrations of sodium chloride, NaCl had any effect on the activity of catechol oxidase, an enzyme found in potatoes. A serial salt-water dilution was made, a potato homogenate made, and buffered catechol oxidase added. The solutions were placed in a spectrophotometer and the light absorbance for each recorded. The higher concentrations of salt, around 20% solution, reduced enzyme activity. We concluded that general increases in the amount of salt molecules in the solution negatively affected the enzymatic activity of the catechol oxidase and markedly …show more content…

Because catechol oxidase is an enzyme, various environmental conditions are able to affect its condition and activity levels. Salt is an ionic compound that dissolves completely in water, pervading the solution with oppositely charged sodium and chlorine ions. These ions interact with the charged R-groups of the protein catechol oxidase and may denature it. Research conducted on apples, a similar testing subject to potatoes as the same enzyme is present in the fruit, has revealed that low levels of salt, between .2 and 1 g/L allowed for the most browning. Concentrations between .05 and 1% inhibit polyphenol oxidase, and concentrations at 20% and above completely inactivate the enzyme according to (insert citation). With this information, it is expected that higher concentrations of salt will significantly lower enzymatic …show more content…

It can be inferred that as sodium chloride, a strong electrolyte, dissolves completely in aqueous solutions, pervading the solution with free sodium and chlorine ions, interferes with the binding of catechol oxidase to the substrate, buffered catechol oxidase. As enzymes are proteins, charged R-groups interact with the oppositely charged ions of salt, altering the enzyme’s shape and rendering it unable to bind. According to (__), the chlorine anion is responsible for the change in enzyme activity. The ions act as noncompetitive inhibitors, binding to sites other than the active site. Because enzyme shape is so specific to its function, even slight interactions are likely to considerably lower its activity. Solutions more concentrated than 20% significantly drop enzyme activity and bring it almost to a halt (Ming Hui Fan et al.,2005). On the other end, our data reflects that too low of a salt concentration may also affect the viability of the enzyme. A 2.5% salt solution exhibited a decrease in activity (Fig. 1) which leads one to believe that the natural salt content of potatoes likely lies around 5%, the optimal concentration

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