Dendrobium orchid

Limpanavech et al. (2008) also used chitosan with of 45 kDa, 90%DD at 1, 10, 50, and 100 ppm to spray on Dendrobium orchid plants. It was found that the chitosan increased significantly... 

Effects of DD%, molecular weight, and concentration of chitosan on floral production of Dendrobium orchid were also studied (Limpanavech et al. 2008). Chitosan 0-80 (45 kDa, >90% DD) at concentrations of 1, 10, 50, and 100 ppm was found to be the most effective on inducing early flowering and increasing in inflorescence number and flowers per inflorescence compared to the control. Treatment of chitosan 0-80 at 10 ppm increased inflorescence number per plant from 5.50 (control) to 7.75 (treatment) and flowers per inflorescence from 5.66 to 6.89. 

Limpanavech, P., Chaiyasuta, S., Vongpromek, R. et al. 2(X)8. Effect of chitosan on floral production, gene expression and anatomical changes in the Dendrobium orchid. Scientia Horticulturae 116 65-72. 

Dendrobium crumenatum Sw., or pigeon orchid, is an epiphyte orchid that grows in India, China, the Philippines, and Malaysia. The stem is 4 mm in diameter and the bulbs are 2-3 cm around. The leaves are 7 X 1.3 cm, linear, and fleshy. The petiole is 4Xl mm. The flowers are white (Fig. 60). 

Cycloaddition reactions of furans are still widely used as key steps in the construction of complex molecules including natural products. As an example, the intramolecular Diels-Alder cycloaddition of 2-amido substituted furans provides a useful tool for the synthesis of fused, nitrogen-containing poly-heterocycles. Thus, thermolysis of 3-substituted amidofuran produces tricyclic indolinone 39 as a 2 1 mixture of diastereomers via amidofuran cycloaddition-rearrangement methodology, which serves as a key intermediate in the total synthesis of ( )-dendrobine, a major component of the Chinese ornamental orchid Dendrobium nobile . 

N-cis- and N-frans-cinnamoylnorcuscohygrine (10 and 11) (cis- and trans-dendrochrysines) have been found in the orchid Dendrobium chrysanthum Wall. (37). The structure determination of these products was based on IR, UV, and NMR spectra for the cinnamoyl residue and on mass spectrometry (N-methylpyr-rolidin-2yl group). 

Dendrobium nobile Lindl. Shi Dou (Orchid) (stem) Dendrobine.50 Analgesic, hyperglycemic, hypotensive, hypothermic. 

Majumder PL, Guha S, Sen S (1999) Bibenzyl Derivatives from the Orchid Dendrobium amoenum. Phytochemistry 52 1365... 

Because orchids are so renowned for the beauty of their flowers, they are commonly cultivated in greenhouses, homes, and in warm and humid climates, in outdoor gardens. The most popular genera of horticultural orchids are Catteleya, Cymbidium, Dendrobium, Epidendrum, and Vanda, all of which are species native to tropical forests. 

Compound 417 from the stems of Dendrobium plicatile [192], agrostonin (421) and agrostonidin (422) from the orchids Agrostophyllum khasiyanum and A. callosum [193], reptanthrin (418) from Bulbophyllum replans [194] are symmetrical dimers, in contrast, isoreptanthrin (419) [194], phoyurmanin E (420) [5], denthyrsinol (423) [195] and gymconopin C (425) [105] appeared to have a dimeric formulation composed of the same monomeric units but linked in an unsymmetrical manner. 

Information on the direct route to the copacamphane skeleton has been obtained by studies on the biosynthesis of dendrobine (39), an alkaloid found in the orchid Dendrobium nobile, and related compounds (1969, 1972, 1973). The presumed route to (39) is shown in Scheme 7 and studies with (3K,55)-[5- Hj]MVA and its (5/ )-isomer have now revealed that a 1,3-hydride shift to the side-chain (previously demonstrated in 1973) involved the same epimeric hydrogen at C-5 of MVA as shifted in the formation of sativene. 

The diacid (172) ( C-labelling indicated by ) was fed to the orchid Dendrobium pierardii and a very efficient incorporation into shihunine was recorded. A very much lower incorporation (a factor of 10" ) was found for pierardine (174) and this may indicate that this alkaloid was not being synthesized at the time of the experiment. 

The alkaloid anosmine (128) was isolated from the orchids Dendrobium anosmum and Dedrobium parishii <68XL905). The suggested molecular structure was confirmed by x-ray crystallographic studies <70ACS397). The imidazolium cation and the adjacent atoms C-1, C-4, C-6, and C-9 are all close to a plane. The two six-membered rings of (128) are in a twisted-chair conformation. 

Dendrobium alkaloids. Alkaloids occurring in the orchid genus Dendrobium. Similar to the Nuphar alkaloids, these are pseudoalkaloids whose C-skeletons originate from terpene metabolism (sesquiterpenes). About 15 alkaloids are known, they were first isolated from Dendrobium nobile and later also from other species a typical representative is denr/w/nne C,6H25N02, Mr 263.38, mp. 134-136°C, [a]i -48.4° (CHjOH). ... 

Flower plants have been treated with chitosan and chitosan derivatives widely in Japan, Thailand, Mexico, China, and Korea. Some species of flowers such as E. grandiflorum, orchid Dendrobium, Gladiolus, and Gerbera have been studied for their treatment with chitosan and their derivatives. Chitosan not only showed plant-growth promotion such as increase in height, leaf area, and biomass but also effected on development of the plants such as stimulation of flower, increase in number of flowers, pigment, and vase life. 

The genus Dendrobium (about 1200 species) is the largest genus of the family Orchidaceae [the largest plant family, with 20-25,000 species (Dressier, 1981)]. Many of these species contain alkaloids and some contain sesquiterpene picrotoxins see Chapter 21). A Chinese drug Chin-Shih-Hu, derived from the orchid Dendrobium nobile, is used... 

Dendrobium alkaloids a group of terpene alkaloids from various species in the orchid genus Dendrobium. The D. are sesquiterpenes with one heterocyclic nitrogen atom. 

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