Medicinal plants : the phytochemical aspects

Plants have contributed enormously to the livelihood of human being. Besides their major use as the sources of food, shelter materials, flavour and fragrance, plants have been the main source of medicines and health care preparations. Human curiosity and their desire to understand their surroundings have evolved into scientific investigations, which eventually led to the proliferation of various scientific endeavours, as we know today. Investigations on medicinal plants have led to the development of modem drugs to combat human and animal ailments. Various scientific techniques have also been developed as the result of these investigations. In our effort to develop the scientific capability in this country, we have embarked on the investigation of our medicinal plants. The outcomes of this effort are several papers, which have been published in reputable journals as well as patents. Recently, there is strong resurgence of interest in the use of medicinal plants (or herbal medicines), in the forms of herbal preparations or those derived from them. In 2002-2003, the global sales are expected to reach 23.2 -62 billion and the annual growth is estimated at 10-20%. The main reasons leading to this trend include the rising cost ofmedical treatment and the beliefthat products derived from natural sources are safe. The fact that many of the current modem drugs were derived from plants has also led to the belief on the efficacy of herbal products. The rising popularity of herbal medicines has led to the growth of the industry, and the lack of stringent regulations relating to the use has raised concern with regards to the efficacy and safety of the products. Several examples on the detrimental effects of herbal preparations have been reported due to intended or unintended mistakes. Several other medical issues include the compatibility of one herbal preparation with other drugs or herbal preparations (when used concurrently), dosages, as well its real medical values since very few comprehensive clinical evaluation were done on these products. This is not surprising since the (chemical) nature of these preparations is entirely different from drugs. Noting the beneficial effects albeit its lacking in scientific evidences, and to safeguard the benefit of using herbs as alternative healthcare agent, ways must be found to enhance the public understanding and awareness on the products they are using. Several approaches have been in use in attempts to standardize the products including the use of thin layer chromatography (TLC) and high pressure liquid chromatography (HPLC), and the pursuit is still continued to establish the more comprehensive method of standardization such as the use of liquid chromatography coupled with mass spectrometry (LC-LMS) and nuclear magnetic resonance (NMR) spectrometry. In this presentation we wish to discuss the development in herbal industry and the issues related to it which are also very much related to the phytochemical aspects of the plants or herbs used. We also wish to highlight the activities and approaches taken up by the Laboratory of Natural Products in Universiti Putra Malaysia. The subjects included in this section will be isolation and identification of bioactive compounds based on bioactivity screening of our biodiverse plant resources and traditional knowledge, synthetic approach to bioactive natural compounds and on-line identification of plant constituents.