Nature endows us with a treasure chest of Green Gold full of amazing 'redox-active' substances which interfere with numerous biological processes in our own body, in animals, bacteria, fungi and plants. Whilst such natural products are all around and also in us, we still do not fully understand how these compounds actually work. This book attempts to resolve some of the mysteries and riddles associated with such products. Written by more than thirty international experts from academia and industry, it places a focus on modern developments in this field and considers such natural products from various angles, from their isolation and characterization all along to product development and commercialization. Throughout, the reader will be confronted with modern approaches which enable the efficient identification and isolation of new natural products, help to elucidate their mode(s) of action and permit practical uses in Medicine, Cosmetics, Agriculture, Industry and as functional foods.