Natural product chemistry is playing a key role in providing structural diversity and this feature
makes them an important source of lead drug candidates to the drug discovery program. Nearly 50% of the
prescribed drugs available on the market are of natural product origin and 25% of these commercially
available drugs are of plant origin. Enzymes are responsible for performing several biochemical processes
including metabolisms, catabolism, signal transductions, cell development and their growth. Over
expression and hyper-activation of enzymes cause several human diseases. With the development of modern
techniques in the field of molecular biology and enzymology, over expression and hyper-activation of
enzymes in the body can easily be diagnosed that led to understand human diseases at the molecular level.
An understanding of diseases at the molecular level resulted in the successful applications of enzyme
inhibitors in clinics to treat these diseases. This chapter describes the discovery of novel glutathione S-transferase,
acetylcholinesterase and α-glucosidase inhibitors from medicinally important plants and their
biomedical applications. Additionally, biotechnological method to produce potent bioactive compounds on a
large scale using biosynthetic information has also been proposed.
Keywords: Natural products, enzyme inhibition, glutathione S-transferase, acetylcholinesterase, α-
glucosidase, phytochemistry, biosynthesis, isolation, pharmacophore, bioactivity.