I think you cannot really use a specific formula for enzyme activity. As pointed out earlier, the activity is measured over time. It may be better to have a plot of absorbance as a function of time, then compare this with a standard curve of a known enzyme standard. Hope this can help.
Absorbance value use in the standard curve and determine the PNP concentration, then, for example, beta-galactosidase activity (U) = PNP conentration x total reaction volume/ reaction time x enzyme volume
hello dear akalesh
I performed catalse activity in brain tissue. The reaction mixture contain buffer tissue homogenate (100ul) and different concentartion of hydrogen peroxide. I observed absorbance change then how can i get result enzyme activity. Can i represent it in unit per mg of protein. And can i also obtain Km and Vmax value through this experiments.
Uma Kant Sharma
University of Allahabad
Universidad Nacional de Mar del Plata
Akalesh Kumar Verma
Morehouse School of Medicine
University of Khartoum
Mohammad Mizanur Rahman
Swapna Simon Ph.D
Rice Research Station, Kerala Agricultural University, Kochi,India.
National University of Singapore
University of Queensland