CHAPTER ONE
INTRODUCTION
 BACKGROUND OF THE STUDY
The universal role of plants in the treatment of disease is exemplified by their employment in all the major systems of medicine irrespective of the underlying philosophical premise. How and when such medicinal plants were first used ,is, in many cases, lost in pre-history, indeed animals other than man , appear to have their own materia medica.(Prajapati, et al., 2003). Nevertheless, it can be said with certainty that vegetable kingdom already existed when man made his appearance on earth. As man began to acquire closure acquaintance with his environment,he began to know more about plants, as these were the only curative agents he had. As he progressed and evolved, he was not only able to sort out which plants could be eaten, but also began to associate curative characteristics with certain plants.
The World Health Organization (WHO, 1978) estimated that 4 billion people(80%) of the world population presently use herbal medicine for one form of primary health or another. Early human recognised their dependence on nature for a healthy life and since that time, humanity has depended on the diversity of plant resources for food, clothing, shelter, and medicines to cure myriads of ailments. However, man did not require the modern methods of investigation to collect for himself a materia medica of plants which he often used in conjunction with magical and other ritual practices. It is interesting to reflect that such collection of herbal medicines compiled over centuries by trial and error, and presumably using the patient as the experimental animal throughout, must surely contain some materials worthy of further investigation and should not be too readily discarded.
Medicinal plants are of great value in the field of treatment and cure of disease. Over the years, scientific research has expanded our knowledge of the chemical effects and composition of the active constituents which determine the medicinal properties of plants. It has now been a universally accepted fact that the plant drugs and remedies are far more safe than synthetic medicines for curing complex diseases. Large numbers of alkaloids, glycosides, and antibiotics have been isolated, identified and used as curative agents. In the western world, as people are becoming aware of the potency and side effects of synthetic drugs, there is an increasing interest in the plant based remedies with a basic approach towards the nature. The future development of Pharmacognosy as well as herbal drug industry would be largely dependent upon the reliable methodologies for identification of marker compounds of the extracts, and also upon the standardization and quality control of these extracts.
Little more needs to be said about the present day importance of medicinal plants for it will be apparent to know that the plant themselves either in the form of crude drugs or even more important for the medicinally active materials isolated from them have been and always will be an important aid to physician in the treatment of disease.
1.2    HERBAL MEDICINE
An herb is a plant or part of a plant valued for its medicinal, aromatic, or savoury qualities. Herbs can be viewed as biosynthetic chemical laboratories, producing a number of chemical compounds. Herbal remedies or medicines consist of portions of plants or unpurified plant extracts containing several constituents, which often work together synergistically. As per WHO definition, there are three kinds of herbal medicines: raw plant material, processed plant material and medicinal herbal products. Herbal drugs are finished labelled products that contain active ingredients such as aerial or underground parts of plant or other plant material or combination thereof, whether in the crude state or as plant preparations. Herbal medicine or herbalism is the use of herbs or herbal products for their therapeutic or medicinal value. They may come from any part of the plant but are most commonly made from leaves, roots, bark seeds, and flowers. They are eaten, swallowed, drunk, inhaled, or applied topically to the skin. Herbal products often contain a variety of naturally-occurring biochemicals from plants, many of which contribute to the plant’s medicinal benefits. Chemicals known to have medicinal benefits are referred to as “active ingredients” or “active principles” and their presence depends on a number of factors including the plant species, the time and season of harvest, the type of soil, the way the herb is prepared. Herbal medicines may contain excipients in addition to the active ingredients.