Determination of Laccase activity from Lentinula edodes by 3,3'-dimethylbenzidine

Spectrophotometric determination was taken to evaluate the activity of Laccase from Lentinula edodes by using the o-tolidine(3,3′-dimethylbenzidine) as substrate,and to determine the optimal pH values in varies kind of conditions.It is concluded that in the acetic acid-sodium acetate buffer solution pH value 4 was the optimal for the enzyme assay.53 ℃ of temperature was found to be the optimal under such a condition.90% of Laccase activity could be preserved overnight by keeping temperature at 30 ℃ but its thermal stability was unstable on high temperature and Laccase could easily be deactivated.The Laccase activity was enhanced by about 50% when the bivalent copper ion concentration was between 50 and 60 mg/L and ferrous ion could entirely inhibit the activity of Laccase.