Rotundatin, a new 9,10-didydrophenanthrene derivative from Dendrobium rotundatum

Abstract: The main objective of this paper is to review recent advances in plant drug research and developments in orchid study, in an attempt to provide useful references for plant drug studies. Plants have been used as medicine for millennia. Out of estimated 250 000 to 350 000 plant species identified so far, about 35 000 are used worldwide for medicinal purposes. It has been confirmed by WHO that herbal medicines serve the health needs of about 80 percent of the world's population; especially for millions of people in the vast rural areas of developing countries. Meanwhile, consumers in developed countries are becoming disillusioned with modern healthcare and are seeking alternatives. The recent resurgence of plant remedies results from several factors: 1) the effectiveness of plant medicines; 2) the side effect of most modern drugs; and 3) the development of science and technology. It has been estimated that in the mid-1990s over 200 companies and research organizations worldwide are screening plant and animal compounds for medicinal properties. Actually, several important drugs used in modern medicine have come from medicinal plant studies, eg, taxol/paclitaxel, vinblastine, vincristine, topotecan, irinotecan, etoposide, teniposide, etc. As for drugs derived from orchids, some novel discoveries, both in phytochemical and pharmacological properties, were reported by some universities. However, studies on plants are very limited. Only about a third of the million or so species of higher plants have been identified and named by scientists. Of those named, only a tiny fraction has been studied. Nowadays the linking of the indigenous knowledge of medicinal plants to modern research activities provides a new approach, which makes the rate of discovery of drugs much more effective than with random collection.

Abstract: The aim of this review is to survey the various naturally occurring phenanthrene compounds that have been isolated from different plants. Only one review has previously been published on this topic. Gorham (1989) reviewed the structures, biosynthesis, separations and spectroscopy of stilbenes and phenanthrenes. The present study furnishes an overview of the hydroxy or/and methoxy-substituted 9,10-dihydro/phenanthrenes, methylated, prenylated and other monomeric derivatives, dimeric and trimeric phenanthrenes and their biological activities. A fairly large number of phenanthrenes have been reported from higher plants, mainly in the Orchidaceae family, in the species Dendrobium, Bulbophyllum, Eria, Maxillaria, Bletilla, Coelogyna, Cymbidium, Ephemerantha and Epidendrum. A few phenanthrenes have been found in the Hepaticae class and Dioscoreaceae, Combretaceae and Betulaceae families. Their distribution correlates strongly with the taxonomic divisions. These plants have often been used in traditional medicine, and phenanthrenes have therefore been studied for their cytotoxicity, antimicrobial, spasmolytic, anti-inflammatory, antiplatelet aggregation, antiallergic activities and phytotoxicity. On the basis of 120 references, this review covers the phytochemistry and pharmacology of phenanthrenes, describing 252 compounds. This contribution stems from our work on the medicinal plant Tamus communis.

Abstract: Orchids have been used as a source of medicine for millennia to treat different diseases and ailments including tuberculosis, paralysis, stomach disorders, chest pain, arthritis, syphilis, jaundice, cholera, acidity, eczema, tumour, piles, boils, inflammations, menstrual disorder, spermatorrhea, leucoderma, diahorrhea, muscular pain, blood dysentery, hepatitis, dyspepsia, bone fractures, rheumatism, asthma, malaria, earache, sexually transmitted diseases, wounds and sores. Besides, many orchidaceous preparations are used as emetic, purgative, aphrodisiac, vermifuge, bronchodilator, sex stimulator, contraceptive, cooling agent and remedies in scorpion sting and snake bite. Some of the preparations are supposed to have miraculous curative properties but rare scientific demonstration available which is a primary requirement for clinical implementations. Incredible diversity, high alkaloids and glycosides content, research on orchids is full of potential. Meanwhile, some novel compounds and drugs, both in phytochemical and pharmacological point of view have been reported from orchids. Linking of the indigenous knowledge to the modern research activities will help to discover new drugs much more effective than contemporary synthetic medicines. The present study reviews the traditional therapeutic uses of orchids with its recent advances in pharmacological investigations that would be a useful reference for plant drug researches, especially in orchids.

Abstract: This review provides an informative and broad overview of orchid biotechnology, addressing several important aspects such as molecular systematics, modern breeding, in vitro morphogenesis, protoplast culture, flowering control, flower color, somaclonal variation, orchid mycorrhiza, pathogen resistance, virus diagnosis and production of virus-free plants, functional genomics, genetic transformation, conservation biotechnology and pharmaceutical biotechnology. This resource will provide valuable insight to researchers who are involved in orchid biology and floriculture, using biotechnology to advance research objectives. Producing an improved orchid through biotechnology for industrial purposes or to serve as a model plant for pure and applied sciences is well within reach and many of the current techniques and systems are already employed at the commercial production level.

Abstract: The fresh or dried stems of many Dendrobium species are well known as one of the most expensive tonics in traditional Chinese medicine Documented as a “superior grade” herbal medicine in the ancient text “Shen Nong’s Herbal Classic”, Dendrobium has been used for thousands of years and is now a popular health food worldwide The main chemical components of Dendrobium are alkaloids, aromatic compounds, sesquiterpenoids and polysaccharides, with multiple biological activities, including immunomodulatory, neuroprotective and anti-tumor effects, etc Various qualitative and quantitative methods have been developed for the quality evaluation of Dendrobium In this review, the research progress since the 1930s relating to the chemistry, bioactivity and quality control of Dendrobium is summarized, existing problems and prospects are also discussed

Abstract: An amorphous phenanthrene, named nudol has been isolated from Eulophia nuda , Eria carinata and E. stricta . It was identified as 2,7-dihydroxy-3,4-dimethoxyphenanthrene. Synthesis of nudol and its dimethyl ether is described.

Abstract: Batatasin, which occurs in dormant bulbils of yams (Dioscorea batatas Decne.) and induces dormancy in this organ has been shown by spectrometric analysis and synthesis to be 3,3′-dihydroxy-5-methoxy-bibenzyl.

Abstract: Bulbophyllanthrin, a novel phenanthrene derivative from the orchid Bulbophyllum leopardium , was shown to have the structure 1a mainly on the basis of spectral evidence including 13 C and 2D NMR spectra.

Abstract: Aus Knollen von Loroglossum hircinum (L.) Rich., welche mit dem Pilz Rhizoctonia versicolor Muller et Nuesch infiziert worden sind, wird das fungistatisch wirksame Hircinol, C15H14O3, in Ausbeuten von 250–400 mg pro kg Knollengewebe isoliert. Die Knollen enthalten ferner pro kg ca. 150 mg einer fungistatisch unwirksamen Substanz A. Beide Verbindungen scheinen dem Orchinol, einem aus Orchis militaris L. isolierten Pilzabwerhrstoff, chemisch nahe zu stehen. Substanz A hat sich als identisch mit dem von Hardegger und Mitarb. beschirebene Loroglossol erwiesen.

Abstract: Cirrhopetalanthridin and cirrhopetalidinin, two new stilbenoids isolated from the orchid Cirrhopetalum andersonii , were shown to be 4,7-dihydroxy-2,3-methylenedioxy-9,10-dihydrophenanthrene and 3,2′-dihydroxy-5′methoxy-4,5-methylenedioxy bibenzyl, respectively, from spectral and chemical evidence.