title: In vitro propagation by asymbiotic seed germination and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity studies of tissue culture raised plants of three medicinally important species of dendrobium.
abstract: A simple and efficient plant propagation system has been developed by asymbiotic germination of seeds in three medicinally important Dendrobium species, namely, Dendrobium tosaense, Dendrobium moniliforme, and Dendrobium linawianum. Plants obtained from natural habitats were grown in the greenhouse. The flowers were hand pollinated. Seeds of the capsules derived after 12 weeks of hand-pollination germinated asymbiotically (50-74%) on half strength Murashige and Skoog's (MS) basal medium with 3% sucrose and solidified with 0.9% Difco agar. Active growth in the germinated seedlings was achieved by re-culturing on full strength MS basal medium supplemented with 8% banana homogenate, 8% potato homogenate, 8% coconut water, 1.5% sucrose and 0.9% Difco agar. Healthy plantlets, transferred to plastic trays containing moss or moss and tree fern, successfully acclimatized (84-100%) in the greenhouse. A marked varied response was observed in the free radical scavenging activity of methanolic extracts of in vitro propagated plants, on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical using a UV spectrophotometer assay. Methanolic extracts were prepared by dissolving the powdered plant material, obtained from six months old in vitro propagated plants, each about 5 g, in boiling methanol. The percentage of scavenging effect of D. tosaense extract was 95.9% at 0.4 mg/ml concentration, whereas D. monoliforme, and D. linawianum extracts scavenged 83.4% and 92.3%, respectively, at a concentration of 0.4 mg/ml. All the extracts scavenged DPPH radical significantly in a concentration dependent manner.
authors.affiliation: Department of Agronomy, Chiayi Agricultural Experiment Station, Agricultural Research Institute, Taiwan.
authors.forename: Shu-Fung
authors.initials: SF
authors.lastname: Lo
authors.forename: Satish Manohar
authors.initials: SM
authors.lastname: Nalawade
authors.forename: Vanisree
authors.initials: V
authors.lastname: Mulabagal
authors.forename: Susan
authors.initials: S
authors.lastname: Matthew
authors.forename: Chung-Li
authors.initials: CL
authors.lastname: Chen
authors.forename: Chao-Lin
authors.initials: CL
authors.lastname: Kuo
authors.forename: Hsin-Sheng
authors.initials: HS
authors.lastname: Tsay
mesh_terms: D001713:Biphenyl Compounds / Q000378:metabolism / Q000494:pharmacology*; D031667:Dendrobium / Q000187:drug effects* / Q000254:growth & development; D016166:Free Radical Scavengers / Q000378:metabolism / Q000494:pharmacology*; D018525:Germination / Q000187:drug effects* / Q000502:physiology; D006834:Hydrazines / Q000378:metabolism / Q000494:pharmacology*; D010851:Picrates; D010936:Plant Extracts / Q000378:metabolism / Q000494:pharmacology; D010946:Plants, Medicinal / Q000187:drug effects / Q000254:growth & development; D012639:Seeds / Q000187:drug effects* / Q000254:growth & development; D013559:Symbiosis / Q000187:drug effects; D046509:Tissue Culture Techniques
chemical_list: D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D006834:Hydrazines; D010851:Picrates; D010936:Plant Extracts; C004931:1,1-diphenyl-2-picrylhydrazyl