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Whether natural product drug discovery programs should rely on wild plants collected "randomly" from the natural environment, or whether they should also include plants collected on the basis of use in traditional medicine remains an open question.This study analyzes whether plants with ethnomedical uses from Vietnam and Laos have a higher hit rate in bioassay testing than plants collected from a national park in Vietnam with the goal of maximizing taxonomic diversity ("random" collection).All plants were extracted and subjected to bioassay in the same laboratories. Results of assays of plant collections and plant parts (samples) were scored as active or inactive based on whether any extracts had a positive result in a bioassay. Contingency tables were analyzed using χ(2) statistics.Random collections had a higher hit rate than ethnomedical collections, but for samples, ethnomedical plants were more likely to be active. Ethnomedical collections and samples had higher hit rates for tuberculosis, while samples, but not collections, had a higher hit rate for malaria. Little evidence was found to support an advantage for ethnomedical plants in HIV, chemoprevention and cancer bioassays. Plants whose ethnomedical uses directly correlated to a bioassay did not have a significantly higher hit rate than random plants.Plants with ethnomedical uses generally had a higher rate of activity in some drug discovery bioassays, but the assays did not directly confirm specific uses.Ethnomedical uses may contribute to a higher rate of activity in drug discovery screening.

Tuberculosis has existed in Southeast Asia for thousands of years. Many traditional treatments involve herbal remedies. Over time, these traditional treatments have had the chance to become refined based on efficacy and safety. It was therefore hypothesized that plants that were used in the past and are still used today to treat symptoms associated with tuberculosis are more likely to contain anti-tubercular compounds than plants that have not been used continuously. To try to deduce which plants were used in Laos in the past, a collection of palm leaf manuscripts was studied and a list of plants used to treat symptoms associated with tuberculosis was compiled. Interviews were then conducted with contemporary healers to see if the same plants are still being used today. Plants that were found in the manuscripts and/or are presently used by healers were collected, extracted and were evaluated in an anti-tubercular assay. This paper presents the methods used to identify and collect plants used to treat symptoms indicative of tuberculosis, and the results of anti-TB assays to test for activity.

Ethnobotany/ethnopharmacology has contributed to the discovery of many important plant-derived drugs. Field explorations to seek and document indigenous/traditional medical knowledge (IMK/TMK), and/or the biodiversity with which the IMK/TMK is attached, and its conversion into a commercialized product is known as bioprospecting or biodiversity prospecting. When performed in a large-scale operation, the effort is referred to as mass bioprospecting. Experiences from the mass bioprospecting efforts undertaken by the United States National Cancer Institute, the National Cooperative Drug Discovery Groups (NCDDG) and the International Cooperative Biodiversity Groups (ICBG) programs demonstrate that mass bioprospecting is a complex process, involving expertise from diverse areas of human endeavors, but central to it is the Memorandum of Agreement (MOA) that recognizes issues on genetic access, prior informed consent, intellectual property and the sharing of benefits that may arise as a result of the effort. Future mass bioprospecting endeavors must take heed of the lessons learned from past and present experiences in the planning for a successful mass bioprospecting venture.

An ethnobotany-based approach in the selection of raw plant materials to study was implemented.To acquire raw plant materials using ethnobotanical field interviews as starting point to discover new bioactive compounds from medicinal plants of the Lao People's Democratic Republic.Using semi-structured field interviews with healers in the Lao PDR, plant samples were collected, extracted, and bio-assayed to detect bioactivity against cancer, HIV/AIDS, TB, malaria. Plant species demonstrating activity were recollected and the extracts subjected to a bioassay-guided isolation protocol to isolate and identify the active compounds.Field interviews with 118 healers in 15 of 17 provinces of Lao PDR yielded 753 collections (573 species) with 955 plant samples. Of these 955, 50 extracts demonstrated activity in the anticancer, 10 in the anti-HIV, 30 in the anti-TB, and 52 in the antimalarial assay. Recollection of actives followed by bioassay-guided isolation processes yielded a series of new and known in vitro-active anticancer and antimalarial compounds from 5 species.Laos has a rich biodiversity, harboring an estimated 8000-11,000 species of plants. In a country highly dependent on traditional medicine for its primary health care, this rich plant diversity serves as a major source of their medication.Ethnobotanical survey has demonstrated the richness of plant-based traditional medicine of Lao PDR, taxonomically and therapeutically. Biological assays of extracts of half of the 955 samples followed by in-depth studies of a number of actives have yielded a series of new bioactive compounds against the diseases of cancer and malaria.

The impact of the University of Illinois at Chicago-based Vietnam-Laos International Cooperative Biodiversity Group (ICBG) Program "Studies on Biodiversity of Vietnam and Laos", which has been in operation for the period of 1998-2005, touches on five major areas of endeavor: (a) biodiversity inventory and conservation; (b) studies on medicinal plants; (c) drug discovery and development; (d) economic development; and (e) issues on intellectual property rights and benefit sharing in natural products drug discovery and development. Highlights are presented and the significance is discussed.

Fibroblast growth factor (FGF) from bovine brain has been reported to be a family of three polypeptide fragments derived by limited proteolysis from myelin basic protein (MBP) (Westall, F. C., Lennon, V. A., and Gosopodarowicz, D. (1978) Proc. Natl. Acad. Sci. U. S. A. 75, 4675-4678). However, fragments of sequence similar to the proposed active ones, generated from bovine MBP by acid proteases, are inactive in stimulating [3H]thymidine incorporation in BALB/c 3T3 cells. Further, the principal active component of the brain FGF preparation (Gospodarowicz, D., Bialecki, H., and Greenburg, G. (1978) J. Biol. Chem. 253, 3736-3743) which can be recovered in high yield from isoelectric focusing in sucrose has a pI between 4.8 and 5.8 in contradistinction to the MBP fragments (pI approximately 10) and is not retained on a column of chicken anti-bovine MBP-Sepharose. Therefore, although the reported preparation of brain FGF gives an increase in activity units/mg of protein of about 1000-fold over the crude brain extract, the main protein components, the MBP fragments, do not possess the mitogenic activity. Additional purification of as much as 50- to 100-fold may be required to obtain a homogeneous preparation of the real brain FGF.