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Among all orchids, Dendrobium sp. is considered to have high medicinal value. Dendrobium moniliforme and Dendrobium transparens have immense pharmaceutical, commercial potentiality. However, their fungal endophytes remain unexplored. Isolation and identification of thirteen species of endophytic fungi from the root of D. moniliforme as well as five species from the roots of D. transparens were done. The two endophytic fungi namely Aspergillus flavus and Trichoderma harzianum were common for both plant species. Antimicrobial assay was done against selected human pathogen both gram positive and negative Escherichia coli, Pseudomanas aeruginosa, Staphyllococcus aureus and Staphyllococcus epidermidis. The antimicrobial assay showed the significant role of endophytic fungi to inhibit the bacterial growth. Methanolic extract of DeMon VI and DeMon X were prepared to identify the bioactive compounds. Phenolic and 3-Eicosene,(E)-compounds were identified from extract of DeMon VI whereas Pentadecanoic acid, 14 methyle-, methyl ester and Diethyl Phthalate were identified from extract of DeMon X. Key words: Orchids, Dendrobium sp., endophytic fungi, Human pathogen.

International audience; The present study aims to identify the diverse endophytic fungi residing in the roots of Dendrobium moniliforme and their role in plant growth and development. Nine endophytic fungi were isolated from the root sections and characterized by molecular technique. Quantification of the indole acetic acid (IAA) compound by these endophytes was done. Further, Chemical profiling of R11 and R13 fungi was done by Gas Chromatography-Mass Spectroscopy (GC-MS). Asymbiotic seed derived protocorms of Rhynchostylis retusa was used for the plant growth assay to investigate the growth promoting activities of the fungal elicitor prepared from the isolated fungi from D. moniliforme. Among the isolated fungi, the relative dominant fungus was Fusarium sp. The R13 and R6 fungi were identified only at the genus level which concludes the fungi are of new species or strain. The indole acetic acid production was relatively higher in R10. Bioactive compound diversity was observed in the organic extract of R11 and R6. The presence of phenolic compound and essential oil suggest their contribution for the antimicrobial and antioxidant properties to their host plant, D. moniliforme. The plant growth assay result concluded, the fungal elicitor prepared from R10, Colletotrichum alatae was the best among all other for the plant growth activities.

Rhododendron arboreum, family Ericaceae, is a medium size tree 7-14m height or shrub, Widely distributed in Nepal all along sub-tropical and temperate regions from 1200-3300m, the Rhododendron arboreum is known as ‘Gunras’ in Nepali. R. arboreum was declared of Nepal’s national flower in 1962 by government of Nepal. The chemical compositions of the wood (stem) Of Rhododendron arboreum has been investigated on the basis of useful methods of Tappi & ASTM. The main chemical compositions were:-Ash content (0.75%), Extractives (4.39%), Hollocelluloses (69.82%), Hemicelluloses (22%), alpha-celluloses (47.98%), Pentosans (16.84%), & Lignins (24.88%). The Lignins were analyzed by UV &IR. Similarly, the fatty acid compositions of extractives were analyzed by GC/MS. The main fatty acid compositions were: Butanoic acid, Pentanoic acid, 4-Heptenoic acid, & 8-Nonynoic acid in extractives. The solubility of wood in various solvents is a measure of extraneous components content. The solubility of different solvents were: - in cold water (7.02%), Hot water (8.47%), & 1% NaOH (19%). The high percentage of alpha celluloses in chemical compositions shows prospective use as a raw material for paper production along with Danphebholua (Lokta) in cottage industries of Nepal.DOI: http://dx.doi.org/10.3126/jncs.v30i0.9376Journal of Nepal Chemical Society Vol. 30, 2012 Page: 97-106 Uploaded date: 12/19/2013

Eight new homo-and hetero-leptic bismuth(III) complexes and two new polynuclear bismuth(III) oxido clusters derived from acetosulfame (AceH) and cyclamic acid (CycH2) have been synthesised and characterised. Complexes, [Ph2Bi(Ace)] 1, [Bi(Ace)3] 2, [PhBi(Ace)2] 3, [Bi(CycH)3] 6, [Ph2Bi(CycH)] 7 and [PhBi(CycH)2] 8 were synthesised by treating BiPh3 with the appropriate acid in 1:1, 1:2 and 1:3 stoichiometric ratios under solvent-free or solvent-mediated conditions. Complex 4, [Bi(OH)(Ace)2], was obtained from the hydrolysis of 3. [Bi2(Cyc)3] 9 was obtained from the reaction of cyclamic acid with (Bi(OtBu)3) in a 3:2 ratio under inert conditions. The polynuclear bismuth oxido clusters, [Bi50O64(Ace)22(H2O)10] 5 and [Bi38O45(CycH)24(H2O)14] 10 were obtained using Bi2O3 under sonication in water and their composition confirmed through elemental and thermogravimetric analyses. The DMSO soluble complexes, 1, 2, 4, 5, 6, 7 and 9, were all assessed for their in-vitro activity against three strains of H. pylori (251, 26695 and B128). All compounds gave an MIC value of 6.25 μg/mL, indicating that bactericidal activity is insensitive to increased substitution by acetosulfamate or cyclamate at the Bi(III) centre.

The total ash content and inorganic elemental compositions of the wood of Ficus religiosa L. from Nepal had been studied. The percentage of total ash content were found highest in comparison to other Ficus species. Different eight inorganic elements were detected from wet ash analysis by atomic absorption spectroscopic ( AAS) method. The remarkably high concentrations of K, Ca and Mg were also reported.DOI: http://dx.doi.org/10.3126/jncs.v27i1.6664 J. Nepal Chem. Soc., Vol. 27, 2011 74-77

Nine different β-thioxoketones of general formula R(1)C(=O)CH2C(=S)R(2) (R(1) = C6H5, R(2) = C6H5L1; R(1) = C6H5, R(2) = p-CF3C6H4L2; R(1) = p-MeOC6H4, R(2) = C6H5L3; R(1) = p-MeOC6H4, R(2) = p-CF3C6H4L4; R(1) = C5H4N, R(2) = C6H5L5; R(1) = p-IC6H4, R(2) = C6H5L6; R(1) = C6H5, R(2) = p-IC6H4L7; R(1) = C6H5, R(2) = C10H7L8 and R(1) = CH3, R(2) = C6H5L9) and their tris-substituted bismuth(III) complexes having the general formula [Bi{R(1)C(=O)CHC(=S)R(2)}3] were synthesised and fully characterised. The solid state structure of [Bi{C5H4NC(=O)CHC(=S)C6H5}3] B5 was determined by crystallography and revealed that the three β-thioxoketonato ligands are bound to bismuth(III) centre in a bidentate fashion through O and S atoms. The bismuth(III) complexes and the corresponding thioxoketones were assessed for their activity against H. pylori. All of the bismuth(III) complexes were highly active against H. pylori having a MIC of greater than or equal to 3.125 μg mL(-1), while the free acids were essentially not toxic to the bacteria. The anti-leishmanial activity of all the bismuth(III) β-thioxoketonates and the corresponding free acids were assessed against L. major promastigotes. The toxicity towards human fibroblast cells was also assessed. All of the free β-thioxoketones were selectively toxic to the L. major promastigotes displaying some potential as anti-leishmanial agents. Among these [C6H5C(=O)CH2C(=S)C6H5] L1 and [C5H4NC(=O)CH2C(=S)C6H5] L5 showed comparable activity to that of Amphotericin B, killing about 80% of the L. major promastigotes at a concentration of 25 μM (6.0 μg mL(-1)). The bismuth(III) β-thioxoketonate complexes were toxic to both the L. major promastigotes and fibroblast cells at high concentrations, but gave no improvement in anti-leishmanial activity over the free β-thioxoketones.