If you want to find new plant with hepatoprotective effect try to search in grand mother's medical recipe (ethnopharmacology) it is very helpful.
If you want to find new plant with antioxidant effect, I think that most plants have antioxidant effect since they contain phenolics or other natural products.
Dear Aravind singh sir,actually i am asking for searching criteria of unexplored plants for hepatoprotective activity in india.i have to choose unexplored plants for my Ph.D work.
I am not sure what the end purpose of your work is, but be careful in focusing too much on antioxidant activity - beyond the wide range of methods that give varying results depending on the matrix, a couple of decades of research on antioxidants in the field of nutrition has not found any support for antioxidant activity as a relevant mechanism in prevention or curing disease. If you're looking to specifically stop lipid oxidation in food products, for example, then yes, antioxidant activity is something worth investigating.