methanol controlled study 43 plant extract 39 Article 38 unclassified drug 38 nonhuman 37 plant leaf 29 male 28 Plant Extracts 23 animal experiment 22 chemistry 21 antioxidant activity 18 Methanol 17 animal model 17 human 17 rat 17 antioxidant 16 Animals 15 article 14 flavonoid 14 Antioxidants 13 animal 13 animal tissue 13 high performance liquid chromatography 13 mouse 13 Male 12 Plant Leaves 12 medicinal plant 12 phytochemistry 12 phenol derivative 11