The document discusses various aspects of antioxidants and screening models used to evaluate antioxidant potential. It introduces free radicals and their sources, types including superoxide, hydroxyl and nitric oxide radicals. Various diseases associated with oxidative stress are mentioned. Different in vitro screening models to test antioxidant capacity against reactive oxygen and nitrogen species are described, including DPPH, ABTS, FRAP, ORAC assays. Natural sources of antioxidants from plants used in Ayurveda and their potential is highlighted.

2. INTRODUCTION

21. What are Antioxidants

26. Need of screening for antioxidants

29. Target Oxidized Target Oxidized antioxidant Antioxidant 1. Competitive Reactive species Reduced reactive species

30. Oxidized antioxidant Antioxidant 2. Non-competitive Reactive species Reduced reactive species

33. Before addition of antioxidant FeCl3 H2O2 EDTA OH Deoxyribose Chromogen TBA

34. After addition of antioxidant FeCl3 H2O2 EDTA OH Deoxyribose Chromogen (532 nm) TBA

36. Before addition of antioxidants agent O2 - Nitro blue terazolium reduction Formazan (560 nm)

37. After addition of antioxidants agent Nitro blue terazolium Reduction Formazan

46. List of Antioxidant plants from “RASAYANA” Acorus calamus Aloe vera Asparagus racemosus Azardirachta indiaca Bacopa monnieri Desmodium gangeticum Phyllanthus emblica Terminalia chebula Tinospora cordifolia Withania somnifera

47. Other Ayurvedic plants Piper betel Santalum album Piper nigrum Swertia chirata Plumbago zeylanica Andrographis paniculata Curculigo Orchioides Glycyrrhiza glabra Hygrophila auriculata Hemidesmus indicus Cassia fistula Punica granatum Mangifera indica Shorea robusta Curcuma longa Cassia sophera Emblica officinalis Calicarpa macrophyla Momordica charantia Allium sativum

48. Ayurvedic plants-----unfolded antioxidant potential Pluchea lanceolata Prunus cerasoides Salix caprea Hyoscymus niger Litea glutinosa Semecarpus anacardium Salmalia malabarica

49. These plants can be acts as best antioxidants. Steppe plants Dessert plants Alpine plants Mountain plants

51. DIETARY ANTIOXIDANT