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New Natural Product (new + natural_product)
Selected AbstractsNew phenyl-ethanediols from the culture broth of Boletus edulisJOURNAL OF BASIC MICROBIOLOGY, Issue 2 2007Wan-Qiu Yang Abstract A new phenyl-ethanediol, (1S)-(4-acetylphenyl)-1, 2-ethanediol (1), and a new natural product, (1S)-(3-ethenylphenyl)-1, 2-ethanediol (2), were isolated from the culture broth of the basidiomycete Boletus edulis together with three related known compounds, 1-(4-ethylphenyl)-1, 2-ethanediol (3), 1-(3-ethylphenyl)-1, 2-ethanediol (4) and 1-(3-formylphenyl)-ethanone (5). Their structures were elucidated by spectroscopic methods including extensive 2D-NMR techniques. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] 1H and 13C NMR assignments for two anthraquinones and two xanthones from the mangrove fungus (ZSUH-36)MAGNETIC RESONANCE IN CHEMISTRY, Issue 5 2007Changlun Shao Abstract We report the unambiguous assignments of the 1H and 13C NMR spectra of one new natural product, namely, 6,8-di-O-methyl versiconol (1) together with one known anthraquinone aversin (2) and two xanthones 5-methoxysterigmatocystin (3) and sterigmatocystin (4). These compounds were all isolated from the mangrove endophytic fungus ZSUH-36 from the South China Sea. 1D and 2D NMR experiments including COSY, HMQC and HMBC were used to elucidate the structures. Variations in the 1H NMR spectrum of 6,8-di-O-methyl versiconol (1) were also observed in the temperature range 25,75 °C. In addition, the plausible biogenetic path from 1 to 2 is discussed. Copyright © 2007 John Wiley & Sons, Ltd. [source] Development of an HPLC-PAD-MS assay for the identification and quantification of major phenolic edelweiss (Leontopodium alpium Cass.) constituentsPHYTOCHEMICAL ANALYSIS, Issue 5 2006Stefan Schwaiger Abstract The analytical assessment of edelweiss (Leontopodium alpinum) herb extracts, used in traditional alpine medicine, has resulted in the development of a HPLC-PAD-MS method that allows baseline separation of almost all constituents. Peak assignment of 14 analytes was achieved by comparison of retention times, UV and mass spectra with those of reference compounds either commercially available (luteolin, apigenin and chlorogenic acid) or isolated from edelweiss plants by column chromatography. Ten of the isolated analytes were identified as the known natural products: quercetin-3- O - , - d -glucoside, luteolin-7- O - , - d -glucoside, luteolin-3,- O - , - d -glucoside, luteolin-4,- O - , - d -glucoside, apigenin-7- O - , - d -glucoside, 6-hydroxy-luteolin-7- O - , - d -glucoside, luteolin-7,4,-di- O - , - d -glucoside, chrysoeriol-7- O - , - d -glucoside, leontopodic acid and 3,5-dicaffeolyquinic acid. One analyte, 3,4,5-tri-(E)-caffeoly-d-glucaric acid proved to be a new natural product and was named leontopodic acid B. Structure elucidation was carried out by means of MS and NMR spectroscopy in all cases. The aerial plant parts of L. alpinum (capitula, inflorescence leaves, stems, stem leaves and leaves of the basal rosette) showed variable amounts of the above-mentioned constituents, although qualitative differences were not observable. Copyright © 2006 John Wiley & Sons, Ltd. [source] Date seed oil limit oxidative injuries induced by hydrogen peroxide in human skin organ cultureBIOFACTORS, Issue 2-3 2007Ines Dammak Abstract The skin is chronically exposed to pro-oxidant agents, leading to the generation of reactive oxygen species (ROS). To protect the skin against an over-load of oxidant species, we studied the chemoprotective effect of one new natural product: "date seed oil: DSO". This oil may serve as a potential source of natural antioxidants such as phenols and tocopherols. Here, the antioxidative potential of DSO was compared that of to extra virgin olive oil. Adult human skin was maintained in organ culture in the presence of the DSO and extra virgin olive oil before the addition of hydrogen peroxide (H2O2 ), in order to prevent the tissue from its oxidizing effects. Skin specimens were collected for histology and for melanin studies. In the investigated model system, DSO protects skin against oxidative injuries. It has a significant chemoprotective effect, by inhibition of damage caused by H2O2 compared with specimens without such addition endowing with a radical scavenging ability. The various components from DSO were much more potent antioxidant and more free radical scavengers of the H2O2 than those of olive oil. Our study shows that topical DSO treatment of the skin stimulates events in the epidermis leading to repair skin damage possibly due to antioxidant synergisms. [source] From the Linden Flower to Linden Honey , Volatile Constituents of Linden Nectar, the Extract of Bee-Stomach and Ripe HoneyCHEMISTRY & BIODIVERSITY, Issue 12 2004Regula Naef Honey is produced by honeybees (Apis mellifera), which collect nectar from flowers, digest it in their bodies, and deposit it in honeycombs, where it develops into ripe honey. We studied the evolution of the volatile constituents from the nectar of linden blossoms (Tilia cordata) to honey via the ,intermediate' honeybee. The sampling of the contents of the honey stomach or honey sack of the bee is unique. Extracts were prepared from nectar, from the liquid of the honey stomach, and from ripe honey. The chemistry is extremely complex, and compounds spanning from monoterpenes (hydrocarbons, ethers, aldehydes, acids, and bifunctional derivatives), isoprenoids, aromatic compounds (phenylpropanoids, phenols), and products degraded from fatty acids to alkaloids, were identified. Some compounds definitely stem from the plants, whereas other interesting constituents can be attributed to animal origin. Two derivatives of decanoic acid, 9-oxodec-2-enoic acid (12) and 9-hydroxydec-2-enoic acid, identified in the honey are known to be constituents of the so-called ,Queen's pheromone'. Two metabolites of these acids were identified in the extract of the honey stomach: 8-oxononanal (10), a new natural product, and 8-oxononanol (11). There structures were confirmed by synthesis. Nectar and honey stomach contain many aldehydes, which, due to the highly oxidative atmosphere in the honeycomb, are found as corresponding acids in the honey. Two acids were newly identified as 4-isopropenylcyclohexa-1,3-diene-1-carboxylic acid (14) and 4-(1-hydroxy-1-methylethyl)-cyclohexa-1,3-diene-1-carboxylic acid (15). [source] | |||||||||||||