Medicinal plants have played an important role throughout the world in treating and preventing human diseases. The subject matter of the present volume provides a basis for such therapeutic values and chemical constituents. The article on Honey bee products and their phenol compounds reviews the relationship between flavonoids present in the products and plants and diabetes based on various in vivo and in vitro studies. Other bioactive from plants that induces ant diabetic activity, have also been included in four chapters of the volume. Advances in chemical and pharmacological evaluation of Emplace officinal is occurred in the recent past, are very well documented. Novel therapeutic actions have been reported from Wood forded fruticosa, bryophytes, Spirulina and Terminally chebula. Three chapters focus on the types of chemical compounds found in anti-inflammatory phytomedicines. Besides, the beneficial effects of some active constituents and mechanisms of action of popular phototherapeutic products used in the prevention or/treatment of hypocholesterolemic/anti-atherosclerosis, antihypertensive, hepatic protective, memory enhancing, Urinary tract disorders, anti-diarrheal are presented. The volume will be useful for all those scientists and researchers in the areas of photochemistry, pharmacology and allied disciplines working in the development of new drugs from natural sources.