Subject: What is the optimal pH and temperature for peroxidase?

I've completed a lab to determine the optimal pH and temperature of peroxidase
activity in potatoes.  My findings are that the optimal pH range is 7.5-8.5 and
optimal temperature range is 20-30 degrees Celsius.  I have found different
results on the Internet and am wondering just what is correct.
I also found that both alcohol (isopropyl 70%) and NaCl are activators of
peroxidase.  Can you corroborate these findings so I may know if I'm on the
right track?  
Many thanks.

Re: What is the optimal pH and temperature for peroxidase?