Effects of Temperature, PH, boiling and concentration on Horseradish Peroxidase

ABSTRACT
The purpose of this report is to find out the effect of change in the Temperature, PH, boiling, concentration in peroxidase activity. Peroxidase is an enzyme that converts toxic hydrogen peroxide (H2O2) into water and another harmless compound. In this experiment we use, turnips and horseradish roots which are rich in the peroxidase to study the activity of this enzyme. The activity of peroxidase with change in temperature was highest at 320 Celsius and lowest at 40C. The activity of peroxidase was highest at a pH of 7, while it was lowest at pH of 9.Peroxidase activity was very low and constant with boiled extract, while the activity was moderate …show more content…
Peroxidase activity is lowest at 40C represented by the blue line ranging from 0.100 A at 20 sec to 0.099 A at 120 sec. The activity at 40C was relatively constant throughout the 120 seconds duration.

Table 2: Effects of pH on Peroxidase Activity (record absorbance at 500nm) Time (sec) | Tube 2 and 3pH 3 | Tube 4 and 5 pH 5 | Tube 6 and 7pH 7 | Tube 8 and 9pH 9 | 20 | 0.235 | 0.262 | 0.396 | 0.244 | 40 | 0.351 | 0.420 | 0.567 | 0.341 | 60 | 0.461 | 0.529 | 0.724 | 0.419 | 80 | 0.579 | 0.632 | 0.889 | 0.510 | 100 | 0.675 | 0.732 | 1.039 | 0.602 | 120 | 0.781 | 0.823 | 1.194 | 0.692 |

Figure 2

From Figure 2 above the optimal pH was 7 ranging from 0.396 A at 20 sec to 1.194 A at 120 sec. At that pH, peroxidase activity was highest. The peroxidase activity was low in both acidic and basic pH. Peroxidase activity was lowest in the basic pH of 9 ranging from 0.244 A at 20 sec to 0.692 A at 120sec.

Table 3: Boiled Peroxidase Results (record absorbance at 500nm) Time (sec) | Tube 2 and 3Normal Extract | Tube 4 and 5Boiled Extract | 20 | 0.362 | 0.026 | 40 | 0.368 | 0.028 | 60 | 0.369 | 0.030 | 80 | 0.364 | 0.031 | 100 | 0.364 | 0.033 | 120 | 0.363 | 0.034 |

Figure 3

From Figure 3 above, the normal extract had a high level of peroxidase activity ranging from 0.362 A at 20sec to 0.363 A at 120sec which was fairly constant while the boiled extract had very low peroxidase activity with equally