Medicinal Plants: Biodiversity and Drugs PDF

Preface

Medicinal plants have been the cornerstone of health care since recorded time. Their myriad uses have been documented and passed down through the generations for over 4,000 years. Numerous drugs, both prescription and over-the-counter, have been made available for many important global diseases since scientifi c investigations began in the early part of the 19th century. Now, in the early part of the 21st century, an urgency to explore these traditional remedies to meet patient needs the world over has emerged. The sciences and the technologies which can be applied to elucidating the safety and effi cacy of traditional medicines have evolved. At the same time, much knowledge of the use of plants in various health practices remains to be recorded. This volume will present an illustrative overview of some selected areas of traditional medicine and the historical and contemporary use of medicinal plants. It will also indicate some of the critical areas of ongoing research which are transforming the study of medicinal plants with a view to enhance the quality of health care for the majority of the people on Earth.

The first chapter (Cordell) offers a brief, but broad, overview of various aspects of traditional medicine, and explores some of the new strategies in regulations, information systems, botany, chemistry, biology and clinical trials which are available to improve the practices of traditional medicine globally. Chapter 2 (Furtado Macedo and Furtado Macedo) examines the important aspect of enhancing the production of biologically important secondary metabolites in traditional medicines, while at the same time improving standardization. In Chapter 3, Hardas and Rai discuss aspects of the importance of collecting, storing and analyzing information on the traditional uses of plants, and developing that information for the purposes of drug discovery. Benko-Iseppon, in Chapter 4, focuses on the many uses of Croton species in northeastern Brazil, and on the need to make studies on distribution and genetic diversity an important aspect of the development of medicinal plants. In a following chapter, the same author describes her research over the past years to examine issues related to the propagation of locally used medicinal plants and the development of a data bank on 160 plant species from nine different ecosystems.

Another ethnomedical study based in Brazil is described by Leitão and co-workers in Chapter 6. Here, remote indigenous communities in Oriximiná were studied for their use of the mega biodiversity in the region, and amazingly uncovered 227 species in 211 genera being used for over 2500 indications. An ethnopharmacological study in eastern Andalusia in Spain is described in Chapter 7 by Benitez et al. in which the literature relating to the known medicinal taxa are analyzed for their chemical and biological effects in comparison with use. As a result, in the studied area of Western Granada province, the use of about 30% of the plants could not be justified.

Propolis is a popular product in several parts of the world with many wide ranging proposed uses. In Chapter 8, Rastrelli and co-workers discuss aspects of the chemistry and biology of propolis derived from various tropical and temperate regions. One of the most devastating diseases in the tropical world is malaria. In Chapter 9, Rahamatullah describes ethnomedical studies in Bangladesh on over 100 plants which are being used in that country for malaria by folk medicine practitioners. Marinoff and Martinez in Chapter 10 describe the uses of Usnea sulcata in the Chaco province in Argentina as an antifungal and hemostatic agent. Another one of the burgeoning global diseases is diabetes, and many plants are used throughout the world. Newmaster and colleagues in Chapter 11 present some of the ethnomedical and scientifi c background to the widespread use of Gymnema sylvestre as an antidiabetic plant.

A frequently unappreciated area of medicinal plant use is that for animal husbandry. Severino and Ambrosio remind us in Chapter 12 that many cultures in the world treat various ailments in both companion and farm animals with natural materials either out of choice or necessity. An area that is developing rapidly in awareness is that of endophytes in plants and the role that they can play in fi nding new natural products with biological activity for drug discovery. Zaferanloo and co-workers in Chapter 13 discuss the strategies which can be applied to traditional medicines for this purpose.

Perhaps the most studied aspect of traditional medicines for drug discovery is in the realm of cancer chemoprevention and therapy, which has resulted in several clinically useful agents. Accame and co-workers in Chapter 14 discuss some of the latest developments in this area. Dominguez and co-workers in Chapter 15 present some of the recent studies related to traditional medicines and the inhibition of reactive oxygen species as a way to prevent neurodegenerative diseases. Infl ammatory diseases and the role of herbal preparations in their treatment are the focus of Chapter 16 by Talhouk and co-workers. Experimental aspects of the development of traditional medicines as anti-diabetic agents using in vitro bioassays are discussed by Mahomoodally in Chapter 17.

A different perspective on propolis is offered by Robles-Zepeda and co-workers in Chapter 18, where the focus is placed on aspects of the chemistry arising from the different fl oral origins of bee glue. Zari in Chapter 19 discusses some of the medicinal aspects of various essential oils now widely used as remedies for skin ailments to cancer. The uses of essential oils as antibacterial and antiviral agents are discussed by Reichling in Chapter 20, and the techniques for solvent selection for the effective isolation of natural products through countercurrent chromatography is described by Leitão in Chapter 21.

It is hoped that this sprinkling of chapters will demonstrate the diverse implications for traditional medicine in health care, and the tremendous opportunities that exist to take traditional medicine to the next level of scientifi c development for the prevention and treatment of a wide range of disease states. Strategic investment in potentiating these opportunities is critical for the future of humankind.

We would like to thank Dr. Jose-Maria Prieto, England, Prof. Susana Zacchino, Argentina, Prof. M. Shahabuddin Choudhuri, Bangladesh, Dr. Shandesh Bhattacharya, Nepal, Professor Sitesh Bachar, Dhaka Bangladesh, Dr. Rabih Talhouk, Lebanon, Prof. Dr. Jürgen Reichling, Germany, Dr. Guillermo Benitez, Spain, Prof. Carlo Mattia, Italy, Prof. Mohammed Rahmatullah, Dhaka Bangladesh, Dr. Ramón Robles-Zepeda, Mexico for their help in reviewing the manusript.

Finally, MKR wishes to thank Indar, Avinash, Rathod, Shital, Mudassir and Sonal for help and support during the preparation of the book.