ABSTRACT
Globally, there is a growing need for the search of chemical compounds from natural sources for the treatment of human chronic diseases such as diabetes, microbial infections, cancer, and so forth. Over the years plants have become a major source of such chemical compounds known as phyto-chemicals with different medicinal and biological activities. The aim of this topical study is to provide a succinct knowledge on the biological roles of phytochemicals. This would serve as a veritable resource in the area of phytochemistry. There are many phytochemicals that can be found in plants. This chapter focuses on eight major phytochemicals found in most plants; tannins, saponins, alkaloids, flavonoids, glycosides, oxalates, protease inhibitors, and amylase inhibitors. Most phytochemicals are obtained from the seeds, fruits, bark, and leaves of different medicinal plants or legumes. Their different biological roles such as antioxidant, antibacterial, antitumor, antidiabetic, antiviral activities, and so forth, have been discussed.
