**Chapter 15 289**

Pharmacognosy: Importance and Drawbacks *by Fatai Oladunni Balogun, Anofi Omotayo Tom Ashafa, Saheed Sabiu, Abdulwakeel Ayokun-nun Ajao, Chella Palanisamy Perumal, Mutiu Idowu Kazeem and Ahmed Adebowale Adedeji* 

Preface

Pharmacognosy is a field of natural product chemistry that deals with secondary metabolites isolated from different natural sources, such as plants, animals, fungi, mushrooms, marine coral, sponges, and fish. Thousands of drugs have been isolated from these sources, including artemisinin from *Artemisia annua*, Taxol from the Pacific yew tree, morphine alkaloid from opium, ephedrine from *Ephedra*, quinine from *Cinchona*, and pilocarpine from *Pilocarpus*. The importance of natural product chemistry cannot be ignored because it has provided many active constituents throughout all periods of time, from the Stone Age to the present day. Many of the medicinal plants in different countries, especially in the Gulf region, have not yet been investigated, and their constituents need to be explored. According to the World Health Organization, 80% of people still rely on plant-based traditional medicines for primary health care and 80% of 122 plant-derived drugs are related to their original ethnopharmacological purpose. Therefore, secondary metabolites are

**Shagufta Perveen and Areej Mohammad Al-Taweel**

King Saud University, Riad, Saudi Arabia

good models for developing important drugs.
