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Biomedical subjects

D D Soejarto

Publications and source records attributed to D D Soejarto.

At least 19 recordsLinked to original sources
PubMed2006

Medicinal plants: an important asset to health care in a region of Central Laos.

A field survey of commonly used medicinal plants in the district of Paksan, Bolikhamsai Province in the Lao People's Democratic Republic (Lao P.D.R.) indicates that 55 species of plants, belonging to 49 genera in 31 families of vascular plants, are used in day-to-day medical therapy. Lao names along with uses and preparations for remedies are given. Seven species have medicinal uses that overlap with uses reported in the literature. No medicinal uses have been previously reported for 31 of the species collected based on ethnobotanical field interviews, signifying that their uses may be unique to Laos. Nine of the 31 previously unreported species are mentioned as medicinals multiple times, indicating that further research may be warranted.

Drugs, Chinese Herbal↗
PubMed2006

Biodiversity as a source of anticancer drugs.

Natural Products have been the most significant source of drugs and drug leads in history. Their dominant role in cancer chemotherapeutics is clear with about 74% of anticancer compounds being either natural products, or natural product-derived. The biodiversity of the world provides a resource of unlimited structural diversity for bioprospecting by international drug discovery programs such as the ICBGs and NCDDGs, the latter focusing exclusively on anticancer compounds. However, many sources of natural products remain largely untapped. Technology is gradually overcoming the traditional difficulties encountered in natural products research by improving access to biodiverse resources, and ensuring the compatibility of samples with high throughput procedures. However, the acquisition of predictive biodiversity remains challenging. Plant and organism species may be selected on the basis of potentially useful phytochemical composition by consulting ethnopharmacological, chemosystematic, and ecological information. On the conservation/political front, the Convention on Biological Diversity (CBD) is allaying the anxiety surrounding the notion of biopiracy, which has defeated many attempts to discover and develop new natural products for human benefit. As it becomes increasingly evident and important, the CBD fosters cooperation and adaptation to new regulations and collaborative research agreements with source countries. Even as the past inadequacies of combinatorial chemistry are being analyzed, the intrinsic value of natural products as a source of drug leads is being increasingly appreciated. Their rich structural and stereochemical characteristics make them valuable as templates for exploring novel molecular diversity with the aim of synthesizing lead generation libraries with greater biological relevance. This will ensure an ample supply of starting materials for screening against the multitude of potentially "druggable" targets uncovered by genomics technologies. Far from being mutually exclusive, biodiversity and genomics should be the driving force of drug discovery in the 21st century.

Animals↗
PubMed2005

Ethnobotany/ethnopharmacology and mass bioprospecting: issues on intellectual property and benefit-sharing.

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.

Conservation of Natural Resources↗
PubMed2004

The UIC ICBG (University of Illinois at Chicago International Cooperative Biodiversity Group) Memorandum of Agreement: a model of benefit-sharing arrangement in natural products drug discovery and development.

The Convention on Biodiversity mandates a new approach to the discovery of natural product drugs, one that incorporates concepts of national ownership of genetic resources, intellectual property rights in traditional knowledge, and sharing of economic benefits with countries that are the source of new natural products. The International Cooperative Biodiversity Group (ICBG) program was established to support experimentation in implementation of the Convention through development and execution of international agreements for bioprospecting. The agreement of one such ICBG program, between the University of Illinois at Chicago and institutions in Vietnam and Laos, is presented here. The core elements contained in the single, five-way Memorandum of Agreement are the arrangements for intellectual property rights, treatment of informed consent, and plans for benefit-sharing (including the sharing of short- and long-term royalty benefits, capacity building, and community reciprocity). Program participants were able to develop a practical and flexible agreement that satisfies the wishes of all institutions that are parties to it.

Africa↗
PubMed2003

Traditional herbal drugs of Southern Uganda, II: literature analysis and antimicrobial assays.

Continuing field interviews brought the total species used for disease treatment by herbalists of the majority Baganda Tribe of southern Uganda to 168. Literature searches provided support for the ethnomedical claims for a number of these species, and provided criteria for the species classification into four categories of use validation. They also helped guide the selection of species for recollection, for chemical extraction and further testing in laboratories of the Uganda Ministry of Health and the University of Illinois at Chicago. Many species proved active against microorganisms in several susceptibility assays conducted in Uganda and the US.

Anti-Infective Agents↗
PubMed2003

Traditional herbal drugs of southern Uganda. Part III: isolation and methods for physical characterization of bioactive alkanols from Rubus apetalus.

The East African plant Rubus apetalus Poir. was collected as a component of an ethnobotanical survey in southern Uganda. No phytochemical investigations of this plant have been found in the literature. Preliminary antimicrobial susceptibility tests performed in Uganda indicated biological activity against several bacterial and one fungal human pathogen. Bulk re-collection of Rubus apetalus was accomplished and crude extraction performed in preparation for further testing. Two chemical fractions of the crude extract were active in the antimicrobial susceptibility assay. Fractionation of one of the active crude fractions led to the isolation and elucidation of a mixture of related compounds that exhibit antimicrobial activity against Staphylococcus aureus (MIC=62 microg/ml), Streptococcus faecalis (16 microg/ml) and Candida albicans (32 microg/ml).

Anti-Infective Agents↗
PubMed2001

A pregnane steroid from Aglaia lawii and structure confirmation of cabraleadiol monoacetate by X-ray crystallography.

The pregnane steroid, (E)-aglawone, along with four known triterpenes, and a known sterol mixture were isolated from the bark of Aglaia lawii (Wight) Saldanha ex Ramamoorty (Meliaceae). The structural determination/identification was accomplished by a combination of 1D- and 2D-NMR spectroscopic techniques. The relative stereochemistry of the known triterpene, 20S,24S-epoxydammarane-3alpha,25-diol acetate, was also unequivocally determined for the first time by X-ray crystallography. The isolates were not active against various human cancer cell lines.

Crystallography, X-Ray↗
PubMed2001

Bioactive constituents of the roots of Licania intrapetiolaris.

Fractionation of a methanol extract of the roots of Licania intrapetiolaris, as directed by activity against the KB assay, has led to the isolation of two novel clerodane diterpenoids, intrapetacins A (1) and B (2), and the known triterpenoid cucurbitacin B (3). The structures of 1 and 2 were deduced from one- and two-dimensional NMR experiments, including relative stereochemical assignments based on NOESY correlations and COSY coupling constants. Compound 3 was the most potent against the KB assay, but both 1 and 2 displayed moderate cytotoxicity. When evaluated against an antifungal assay using Aspergillus niger, 2 caused a significant zone of inhibition of fungal growth, while 1 was completely inactive. To the best of our knowledge, this is the first report of the isolation of bioactive compounds from the genus Licania.

Aspergillus niger↗
PubMed2001

Antimalarial compounds from Rhaphidophora decursiva.

Bioassay-directed fractionation led to the isolation of 14 compounds, six of which possess antimalarial activity, from the dried leaves and stems of Rhaphidophora decursiva. Polysyphorin (1) and rhaphidecurperoxin (6) showed strong activities against Plasmodium falciparum. Rhaphidecursinol A (2), rhaphidecursinol B (3), grandisin (4), and epigrandisin (5) were less active against the same organism. Among the isolates, rhaphidecursinol A (2) and rhaphidecursinol B (3) were determined to be new neolignans, and rhaphidecurperoxin (6) is a new benzoperoxide. Known compounds isolated include polysyphorin (1), grandisin (4), epigrandisin (5), (+)-medioresinol, (-)-pinoresinol, (-)-syringaresinol, (+)-glaberide I, (+)-dehydrovomifoliol, (-)-liliolide, (-)-hydroxydihydrobovolide, and N-butylbenzamide, of which compound 1 appears worthy of further evaluation as an antimalarial agent. Structure elucidation and identification were accomplished by spectroscopic means including 1D and 2D NMR analyses.

Animals↗
PubMed2001

Biological screening of rain forest plot trees from Palawan Island (Philippines).

Study plots totaling 0.2 Ha were established in primary forest in the highlands of central Palawan Island, Philippines. Samples of various anatomical parts [typically leaf + twig (If/tw), stem bark (sb), and root (rt)] were collected from all tree species represented within the plots by individuals having a diameter at breast height > or = 10 cm. In all, 211 distinct samples were obtained from 68 tree species, representing 35 families (not including samples from 4 indeterminate species). Methanol extracts of these samples were tested in in vitro antiplasmodial, brine shrimp toxicity, and cytotoxicity assays. The following samples showed an IC50 < or = 10 microg/mL against either chloroquine-sensitive or chloroquine-resistant clones of Plasmodium falciparum: Acronychia laurifolia (sb), Agathis celebica (lf/tw), Aglaia sp. 1 (sb), Aglaia sp. 2 (lf/tw, rt), Bhesa sp. 1 (rt), Cinnamomum griffithii (lf/tw), Croton leiophyllus (rt), Dysoxylum cauliflorum (rt), Garcinia macgregorii (sb), Lithocarpus sp. 1 (rt, sb), Meliosma pinnata ssp. macrophylla (lf/tw, rt), Myristica guatteriifolia (lf/tw), Ochrosia glomerata (rt, sb), Swintonia foxworthyi (lf/tw), Syzygium sp. 1 (rt), Turpinia pomifera (rt), and Xanthophyllum flavescens (sb). Secondly, those samples which displayed > or = 50% immobilization of brine shrimp at 100 microg/mL were: Acronychia laurifolia (lf/tw/fruit, rt, sb), Agathis celebica (lf/tw, sb), Aglaia sp. 1 (lf/tw), Alphonsea sp. 1 (rt), Ardisia iwahigensis (lf/tw), Arthrophyllum ahernianum (lf/tw, rt, sb), Castanopsis cf. evansii (rt), Cinnamomum griffithii (lf/tw, rt), Croton argyratus (lf/tw), C. leiophyllus (lf/tw, rt), Dysoxylum cauliflorum (fruit, lf/tw, rt), Euonymus javanicus (rt), Glochidion sp. 1 (rt), Polyosma sp. 1 (rt), Symplocos polyandra (rt), Timonius gammillii (sb), and Xanthophyllum flavescens (rt). Lastly, samples which exhibited an IC50 < or = 20 microg/mL against one or more of the cancer cell lines employed (LU1, KB, KB-V1, P-388, LNCaP, or ZR-75-1) include: Acronychia laurifolia (lf/tw/fruit, rt, sb), Aglaia sp. 1 (sb), Aglaia sp. 2 (rt), Alphonsea sp. 1 (rt), Ardisia iwahigensis (lf/tw, rt, sb), Astronia cumingiana (sb), Croton argyratus (lf/tw, rt, sb), C. leiophyllus (lf/tw, rt), Dimorphocalyx murina (lf/tw, rt, sb), Lithocarpus caudatifolius (rt, sb), Litsea cf. sibuyanensis (rt), Syzygium cf. attenuatum (rt, sb), S. confertum (sb), Ternstroemia gitingensis (rt), and Ternstroemia sp. 1 (rt, sb).

Animals↗
PubMed2000

Traditional herbal drugs of southern Uganda, I.

One-hundred four plant species used medicinally by herbalists from three southern Ugandan tribes were collected and identified. The collection includes a large portion of the materia medica of the Abayanda of the southwest region, as well as species used by herbalists of the Baganda and Bakiga Tribes. Literature searches were performed in preparation for further collections, and for collaborative laboratory validation of in vitro antimicrobial activity. Literature data provide support for ethnomedical claims for a number of species used in Uganda for disease treatment.

Data Collection↗
PubMed1999

Quinoline alkaloids from Acronychia laurifolia.

Bioassay-directed fractionation of a root extract of Acronychia laurifolia (Rutaceae) using the KB-V1+ human tumor cell line led to the isolation of six quinoline alkaloids. One of these alkaloids is novel, namely, 2,3-methylenedioxy-4,7-dimethoxyquinoline and the other five were identified as the known compounds, evolitrine, gamma-fagarine, skimmianine, kokusaginine and maculosidine. Two known bis-tetrahydrofuran lignans, sesamolin and yangambin, were also identified. The structure of the new alkaloid was determined by spectroscopic methods. All of the isolates were evaluated against a panel of human cancer cell lines; four of the alkaloids showed weak cytotoxic activity.

Alkaloids↗
PubMed1998

Noncariogenic intense natural sweeteners.

There is a definite relationship between the dietary consumption of sucrose and the incidence of dental caries. Noncaloric sucrose substitutes for use in the sweetening of foods, beverages, and medicines may be either synthetic compounds or natural products. In the United States, four potently sweet artificial sweeteners are approved, namely, saccharin, aspartame, acesulfame potassium, and sucralose. Highly sweet plant constituents are used in Japan and some other countries, including the diterpene glycoside stevioside and the protein thaumatin. Recent progress in a research project oriented towards the discovery and evaluation of novel potentially noncariogenic sweeteners from plants has focused on substances in the sesquiterpenoid, diterpenoid, triterpenoid, steroidal saponin, and proanthocyanidin structural classes. The feasibility of using Mongolian gerbil electrophysiological and behavioral assays to monitor the sweetness of plant extracts, chromatographic fractions, and pure isolates has been investigated. An in vivo cariogenicity study on the commercially available natural sweeteners stevioside and rebaudioside A has been carried out.

Animals↗
PubMed1998

Pyranocoumarins from tropical species of the genus Calophyllum: a chemotaxonomic study of extracts in the National Cancer Institute collection.

(+)-Calanolide A, a novel dipyranocoumarin from the Malesian tree Calophyllum lanigerum var. austrocoriaceum, and a closely related compound, (-)-calanolide B, isolated from Calophyllum teysmannii var. inophylloide, are representatives of a distinct class of nonnucleoside HIV-1 specific reverse-transcriptase inhibitor under development as an AIDS chemotherapeutic. NCI repository specimens totalling 315 organic extracts from 31 taxa of Calophyllum were analyzed for related pyranocoumarins using a simple TLC system. A total of 127 extracts was initially classified as "positive"; eight out of the 31 taxa examined, representing perhaps 28 species already described (1/7-1/8 of all the species in this genus), contained prenylated coumarins, suggesting that these compounds, while sometimes abundantly present, are not widespread in the genus. Representative members of the TLC-positive extracts were partitioned between CH2C12 and 25% aqueous MeOH; the CH2C12-soluble materials were then analyzed by TLC and 1H NMR to confirm the presence of pyranocoumarins. The anti-HIV activity of the partitioned extracts are also presented. This study suggested that there are several distinctive coumarin chemotaxonomic markers distinguishing species of this genus.

Anti-HIV Agents↗
PubMed1997

Isolation and structure elucidation of ardisenone: a new, cytotoxic alkenylphenol from Ardisia iwahigensis.

A methanol extract of leaves and twigs from Ardisia iwahigensis demonstrated toxicity toward brine shrimp as well as LNCaP, ZR-75-1, and Lu1 human cancer cells in culture. A novel alkenylphenol, (Z)-1,16-bis(3-hydroxy-5-methoxyphenyl)-10-hexadecene-1,15-dione (ardisenone) (1), was isolated from the extract by bioassay-directed fractionation. This compound demonstrated moderate cytotoxicity against BC1, Lu1, Col2, KB, KB-V1, and LNCaP cell lines.

Animals↗
PubMed1996

Biodiversity prospecting and benefit-sharing: perspectives from the field.

Searching for new biologically active compounds from natural sources starts, obviously, in the field. Plant, microbial or animal materials to be sought and investigated may be selected through a number of approaches. No matter what selection criterion(a) is (are) used, the first step in obtaining the organism concerned is to undertake field collecting work to search for and to collect the organism. Good knowledge on the ecogeographic distribution and precision in the taxonomic identification of the organism(s) sought are crucial if the field work involves the search for a pre-determined organism or set of organisms. Such knowledge and precision during field work are of secondary importance, however, if the search and collection are based on biodiversity or ethnomedical uses, since accurate taxonomic identification may be made at a later date, in a Museum or Herbarium environment. When an individual or institution from a biotechnologically developed country wishes to obtain indigenous raw biological material from a biotechnologically less developed country, an agreement for the procurement of such raw material may be negotiated. Since the effort to search and develop a biologically active compound(s) from natural sources is a long-term process that involves teamwork between field and laboratory scientists, the success of the endeavor will depend in large part on the continued flow of raw material from the field. Goodwill to maintain such a flow may be achieved through appropriate scientific and monetary compensations, both in real-time and in long-term sharing of the benefits of discovery. Only with the prospect of financial return to the supplying country will there be an incentive for the protection of the natural resources towards sustainable use and development, as well as to allow time for continuing explorations and discoveries.

Animals↗
PubMed1996

Costaricine, a new antiplasmodial bisbenzylisoquinoline alkaloid from Nectandra salicifolia trunk bark.

A MeOH extract of Nectandra salicifolia trunk bark, obtained during a diversity-based plant collection in a lower montane rainforest in Costa Rica, showed activity in an in vitro antiplasmodial assay measuring incorporation of [3H]-labeled hypoxanthie by Plasmodium falciparum. In addition to 15 known alkaloids isolated from samples of trunk bark, roots, and leaves/twigs of this species, a new bisbenzylisoquinoline alkaloid (+)-costaricine [(+)-12-O-methyllindoldhamine] (1) was isolated from bark (0.038% yield) and from roots (0.001%). (+)-Costaricine was active in the antiplasmodial assay, with IC50 values of 50 ng/mL vs. the chloroquine-sensitive D6 clone and 294 ng/mL vs. the chloroquine-resistant W2 clone of P. falciparum.

Alkaloids↗