recent time plants are been used as a major source of medicine. Medicinal
plants play a key role in the health care system of almost all countries. These
medicines have come from various sources of materials including terrestrial
plants, terrestrial microorganisms, marine organisms and terrestrial
vertebrates and invertebrates (Newman et al., 2000). Through trial and
error, early mankind has found medicinal properties in the seeds, leaves, barks
and roots of certain medicinal plants.
medicine refers to a broad range of ancient and natural health care practices
including tribal/folk medical practices as well as classical systems of
medicine such as Ayurveda, Siddha and Unani. These medical practices originated
much before the application of modern scientific method. Further the herbal
medicines are also used as self-medication in all cultures.
replacement of herbs with synthetic drugs is a relatively new phenomenon, less
than a century old, born largely out of economic opportunities afforded by
patent laws. Drug companies can’t typically patent commonly used plants, but
they can develop patented, proprietary synthetic drugs, often reaping billions
in sales. Since 1940’s, chemists employed by pharmaceutical companies have
developed novel synthetic molecules which have replaced plant medicines, and
are sold both over the counter and by prescription.
results of this synthetic drug explosion have been unfortunate. Today, drugs
prescribed in hospitals constitute the number six cause of death among American
adults. This exceeds deaths due to crack, handguns, and traffic accidents
combined. Addition to that figure the number of adult and child deaths
attributable to over the counter and prescription drugs given outside of
hospitals, and the figures are even worse.
medicines are far and away safer, gentler and better for human health than
synthetic drugs. This is so because human beings have co-evolved with plants
over the past few million years. Ingredients in plants, from carbohydrates, fats
and protein to vitamins and minerals, are part of our body composition and
chemistry. Some compounds perform the same functions in plants and in the body.
Natural antioxidants like phenols in plants, for example, protect plant cells
from oxidation, and often perform the same function in the human body. Our
bodies recognize the substances that occur in plants, and possess sophisticated
mechanisms for metabolizing plant materials.
same cannot be said about synthetic drugs. These agents are most often alien to
the chemistry of the human body and are separate and apart from the careful
crafting of evolution. Synthetic drugs often act in the body as irritants and
toxins, upsetting the balance of whole systems, producing side effects that can
be lethal. By contrast, the regular and judicious use of herbs to protect and
promote health and as medicines to help treat common ailments is an enlightened
approach to personal well-being.
the last few decades, there has been an exponential growth in the field of
herbal medicine. Use of indigenous drugs
from plant origin forms a major part of complementary and alternative
medicine/traditional medicine (CAM/TM). The world market for herbal medicine,
including herbal products and raw materials has been estimated to have an
annual growth rate between 5 and 15%. Total global herbal drug market is
estimated as US $62 billion and is expected to grow to US $5 trillion by the
year 2050. India has a great wealth of traditional knowledge and wisdom. The
Indian medicinal plants-based industry is growing at the rate of 7–15%
annually. The value of medicinal plants-related trade in India is estimated at
Rs 5000 crores per annum. Global trend leading to increased demands of
medicinal plants for pharmaceuticals, phytochemicals, nutraceuticals, cosmetics
and other products is an opportunity sector for Indian trade and commerce.
Scientifically validated and technologically standardized herbal medicines may
be derived using a safe path of reverse pharmacology approach based on traditional
knowledge database. This may play a vital role in drug discovery, development
and therapeutics, in addition to dealing with a typical Western bias against
Ayurveda (Kalpana et al., 2004).
products have played an eminent role in the discovery and development of new
drugs (Newman et al., 2000; Lee, 2004; Harvey 2000; Tulp and Bohlin,
2002). Over half of the nearly 1000 small-molecule drugs introduced in the
market over the past two decades are either natural products or in some way
related to natural products (Newman et al., 2003). The pharmaceutical
industry depends on the generation of new drugs. The drug discovery process is
devoted to the identification of compounds that can cure or help to treat
diseases. The past decade has seen tremendous progress in many of the different
aspects of the drug-discovery process. These aspects include the development of
combinatorial chemistry technologies, the implementation of high-throughput
screens and bioinformatics tools, the sequencing of the human and other
genomes, as well as the integration of functional genomics platforms (Bleicher et
al., 2003). Although rendering many new potential biological target
molecules, this route of industrializing the drug-discovery process failed,
however, to deliver the number of lead compounds required to maintain the
necessary productivity of pharmaceutical R&D (Bailey and Brown, 2001;
Reichert, 2003). The efforts aimed at increasing the output of lead compounds
relied too strongly on a quantitative increase of compounds to enter the
screening process, while qualitative aspects were neglected (Breinbauer et
al., 2002; Ortholand and Ganesan, 2004; Piggott and Karuso, 2004).
The technologies of combinatorial
chemistry have not yielded the promised new drugs in a timely, more efficient
manner, the heavily-marketed drugs that are introduced are often for benign
diseases where both prescription charges and re-imbursement rates are high, and
the public trust in big pharma as a result of unethical withholding of
unfavorable clinical data prior to or post introduction has led to important
clinical entities being withdrawn and voluminous litigation ensuing. As safety
standards, and therefore costs, to introduce new entities increases, even fewer
companies will be fiscally able to introduce new entities. Due to the
structural and biological diversity of their constituents, terrestrial plants
offer a unique and renewable resource for the discovery of potential new drugs
and biological entities (Shu, 1998).