What is the reason of getting Negative Value of percentage inhibition in invitro antioxidant assay by hydroxyl radical scavenging assay?

I am about to evaluate antioxidant activity of my aqueous crude extract by invitro method i.e Hydroxyl radical scavenging assay and hydrogen peroxide scavenging assay.i got test and control...

04 April 2018 9,248 6 View