Chemical constituents of Breynia glauca leaves

From the leaves of Breynia glauca, eight compounds including friedelin (1), 3-oxo- 4,5-sitosterone (2), friedelan-3β-ol (3), β-sitosterol (4), kaempferol (5), arbutin (6), kaempferol-3-O-rutinoside (7) and quercetion-3-O-glucoside (8) were isolated. The presence of these compounds supports the traditional use of this plant as a detoxifying agent. In addition, all of these chemical constituents were tested for antiviral potential against herpes simplex virus types 1 and 2, but were found to be inactive at 50 μg/ml

Bergenin from Cissus javana DC. (Vitaceae) root extract enhances glucose uptake by rat L6 myotubes

Purpose: To examine the glucose uptake stimulatory activity of the root extract of Cissus javana DC. (Vitaceae) in Lδ myotubes of rat, and also to identify the extract’s active principles.Methods: The methanol extract was prepared from Cissus javana tuberous roots and evaluated for glucose uptake stimulatory effects on Lδ rat muscle cells and inhibitory activity against α-glucosidase. The chemical components were isolated using several chromatographic techniques, and their structures characterized by spectroscopic methods. Each isolate was then assayed for glucose uptake stimulatory and α-glucosidase inhibitory activities.Results: The extract (100 μg/ml) exhibited glucose uptake stimulatory effect (70.9 % enhancement) and α-glucosidase enzyme inhibitory activity (100 % inhibition). Through chromatographic separation, bergenin, stigmast-4-en-3-one and β-sitosterol were isolated and identified. Bergenin, at 100 μg/ml (0.3046 mM), increased glucose uptake by Lδ myotubes by 50.5 % without toxicity. At the same concentration, bergenin showed no inhibition on α-glucosidase enzyme, while stigmast-4-en-3-one and β-sitosterol exhibited 98.6 and 40.6 %, inhibition, respectively.Conclusion: This study is the first report on the chemical constituents, and the glucose uptake stimulatory and α-glucosidase inhibitory activities of Cissus javana DC. roots. The findings reveal the antidiabetic potential of the plant and the glucose-uptake enhancing activity of bergenin. Keywords: Cissus javana, α-Glucosidase, Antidiabetes, Rat skeletal muscle cells, Bergeni

Effects of oxyresveratrol and its derivatives on cultured P19-derived neurons

Purpose: To modify the structure of oxyresveratrol and evaluate the obtained derivatives for effects on neuronal cells.Methods: Electron-withdrawing groups were selectively introduced to the aromatic ring of the core stilbene structure. Oxyresveratrol and derivatives were then evaluated for their ability to enhance the survival of P19 derived neuronal cells by XTT method, in comparison with the widely known antioxidants, Trolox and ascorbic acid. Phase-contrast microscopic images of the neurons under various conditions were also taken and analyzed.Results: Oxyresveratrol, at a very low concentration (1 ng/mL), enhanced the survival of neurons in both normal and serum-deprivation conditions. Higher activity was observed for the 5-formylated and t 5-carboxylated products. The potencies of these polyoxygenated stilbenes were far greater than those of Trolox and ascorbic acid. These observations were supported by results from the examination of the phase-contrast micrographs of the neuronal cells.Conclusion: Oxyresveratrol and some derivatives prepared in this study demonstrate significant cell protective activity and may be of therapeutic value, but further investigations in animals are required to verify their neuroprotective potentials.Keywords: Oxyresveratrol, Artocarpus lacucha, Artocarpus lakoocha, Polyoxygenated stilbenes, Cell protection, Neuro

Immune modulatory effect of a novel 4,5-dihydroxy-3,3´,4´-trimethoxybibenzyl from Dendrobium lindleyi

Dendrobium bibenzyls and phenanthrenes such as chrysotoxine, cypripedin, gigantol and moscatilin have been reported to show promising inhibitory effects on lung cancer growth and metastasis in ex vivo human cell line models, suggesting their potential for clinical application in patients with lung cancer. However, it remains to be determined whether these therapeutic effects can be also seen in primary human cells and/or in vivo. In this study, we comparatively investigated the immune modulatory effects of bibenzyls and phenanthrenes, including a novel Dendrobium bibenzyl derivative, in primary human monocytes. All compounds were isolated and purified from a Thai orchid Dendrobium lindleyi Steud, a new source of therapeutic compounds with promising potential of tissue culture production. We detected increased frequencies of TNF- and IL-6-expressing monocytes after treatment with gigantol and cypripedin, whereas chrysotoxine and moscatilin did not alter the expression of these cytokines in monocytes. Interestingly, the new 4,5-dihydroxy-3,3′,4′-trimethoxybibenzyl derivative showed dose-dependent immune modulatory effects in lipopolysaccharide (LPS)-treated CD14lo and CD14hi monocytes. Together, our findings show immune modulatory effects of the new bibenzyl derivative from Dendrobium lindleyi on different monocyte sub-populations. However, therapeutic consequences of these different monocyte populations on human diseases including cancer remain to be investigated

Cytotoxic and Antimigratory Activities of Phenolic Compounds from Dendrobium brymerianum

Chromatographic separation of a methanol extract prepared from the whole plant of Dendrobium brymerianum led to the isolation of eight phenolic compounds. Among the isolated compounds (1–8), moscatilin (1), gigantol (3), lusianthridin (4), and dendroflorin (6) showed appreciable cytotoxicity against human lung cancer cell lines with IC50 values of 196.7, 23.4, 65.0, and 125.8 μg/mL, respectively, and exhibited antimigratory property at nontoxic concentrations. This study is the first report on the biological activities of this plant

Oxyresveratrol: Sources, Productions, Biological Activities, Pharmacokinetics, and Delivery Systems

Oxyresveratrol has recently attracted much research attention due to its simple chemical structure and diverse therapeutic potentials. Previous reviews describe the chemistry and biological activities of this phytoalexin, but additional coverage and greater accessibility are still needed. The current review provides a more comprehensive summary, covering research from 1955 to the present year. Oxyresveratrol occurs in both gymnosperms and angiosperms. However, it has never been reported in plants in the subclass Sympetalae, and this point might be of both chemotaxonomic and biosynthetic importance. Oxyresveratrol can be easily obtained from plant materials by conventional methods, and several systems for both qualitative and quantitative analysis of oxyresveratrol contents in plant materials and plant products are available. Oxyresveratrol possesses diverse biological and pharmacological activities such as the inhibition of tyrosinase and melanogenesis, antioxidant and anti-inflammatory activities, and protective effects against neurological disorders and digestive ailments. However, the unfavorable pharmacokinetic properties of oxyresveratrol, including low water solubility and poor oral availability and stability, have posed challenges to its development as a useful therapeutic agent. Recently, several delivery systems have emerged, with promising outcomes that may improve chances for the clinical study of oxyresveratrol

Anticancer and antimalarial agents from Thai medicinal plants.

Anticancer and antimalarial agents from Thai medicinal plants

New Biflavonoids with α-Glucosidase and Pancreatic Lipase Inhibitory Activities from Boesenbergia rotunda

Roots of Boesenbergia rotunda (L.) Mansf. are prominent ingredients in the cuisine of several Asian countries, including Thailand, Malaysia, Indonesia, India, and China. An extract prepared from the roots of this plant showed strong inhibitory activity against enzymes α-glucosidase and pancreatic lipase and was subjected to chromatographic separation to identify the active components. Three new biflavonoids of the flavanone-chalcone type (9, 12, and 13) were isolated, along with 12 known compounds. Among the 15 isolates, the three new compounds showed stronger inhibitory activity against α-glucosidase than the drug acarbose but displayed lower pancreatic lipase inhibitory effect than the drug orlistat. The results indicated the potential of B. rotunda roots as a functional food for controlling after-meal blood glucose levels

New Neolignans and a Phenylpropanoid Glycoside from Twigs of Miliusa mollis

From the twigs of Miliusa mollis Pierre, three new compounds including (2S,3S)-2,3-dihydro-2-(4-methoxyphenyl)-3-methyl-5-[1(E)-propenyl]benzofuran, (7S,8S)- threo-Δ8'-4-methoxyneolignan and tyrosol-1-O-β-xylopyranosyl-(1→6)-O-β-gluco-pyranoside were isolated, along with seven known compounds. Their structures were elucidated through analysis of their spectroscopic data