Why is the measured absorbance higher than the control and why does a gel form in my DPPH assay of feruloylated pectin?

My feruloylated pectin (contain ferulic acid=antioxidant) is soluble in water. After adding DPPH prepared in methanol, the color of my sample become brown and it forms a gel. I have tried to...

12 December 2014 3,004 3 View