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One new iridoid glucoside, 7- O - E -feruloylgardoside (1) and two new lignan glycosides, 8′-hydroxyphillyrin (2) and 6''-(p -hydroxybenzyl) phillyrin (3), together with three known compounds, khainaoside B (4), phillyrin (5), and lantibeside (6), were isolated from the whole plants of Lancea tibetica. Their structures were elucidated on the basis of spectroscopic methods and X-ray crystallographic analysis. A DPPH free radical scavenging assay showed that 1 and 4 exhibited moderate antioxidant activity (IC 50 45.05 ± 3.04 and 48.00 ± 3.29 μ g/ml) compared with vitamin C (IC 50 3.31 ± 0.16 μ g/ml). [Display omitted] • One new iridoid glucoside (1) was isolated from Lancea tibetica. • Two new lignan glycosides (2 and 3) were isolated from Lancea tibetica. • Two iridoid glucosides (1 and 4) exhibited moderate antioxidant activity. [ABSTRACT FROM AUTHOR]

Syringa pubescens Turcz is commonly used folk medicinal herb in west of Henan Province of China. In this work, water and various concentration of methanol, ethanol and acetone in water were used as solvent to extract echinacoside and oleuropein from S. pubescens. The antioxidant properties of different extracts were evaluated using various in vitro assays. The highest yields of echinacoside and oleuropein were obtained by using the 60% aqueous methanol and 80% aqueous ethanol, respectively. The extracts of water, aqueous ethanol or methanol showed strong antioxidant abilities. Furthermore, the high correlation between echinacoside content and antioxidant properties was found. The contribution of oleuropein content was not significant to antioxidant abilities. These findings indicate that S. pubescens can be used as a new natural antioxidant resource [ABSTRACT FROM AUTHOR]

[Display omitted] • Two unknown compounds were isolated from Dianella ensifo lia (L.) DC. • The structures for two new compounds were elucidated by spectroscopic analyses. • Compound 2 exhibited inhibitory effects against PTP-1B. The Dianella genus includes approximately 20 species in all over the world. So far, only the chemical constituents of the lipophilic extract from Dianella ensifolia have been investigated. However, there have been no reports of its aqueous extract. In this article, two previously undescribed glucopyranosides, methyl 2-methoxyl-6-methyl benzoate-4-O- β - D -glucopyranoside (1) and methyl 2-hydroxy-3,6-dimethyl benzoate-4-O- β - d -glucopyranosyl-(1→6)- β - d -glucopyranoside (2), were isolated from the aqueous extract of D. ensifolia. Their structures were elucidated by comprehensive spectral measurements and comparisons with data reported in the literature. Compound 2 exhibited inhibitory effects against PTP-1B with an IC 50 value of 12.88 ± 0.87 μM. [ABSTRACT FROM AUTHOR]

• Securiterpenoside G, a new hemiterpene glycoside was isolated. • One new furolactone-type lignan glycoside (2) was identified. • The possible biosynthetic precursor and further metabolite of 2 were determined. • Hemiterpene and furolactone-type lignan glycosides have taxonomic significances. One new hemiterpene glycoside, securiterpenoside G (1), one new furolactone-type lignan glycoside, (7 R ,8 R ,8′ S)-glaberide I 4- O - β -D-glucopyranosyl-(1‴→4″)- O - β -D-glucopyranoside (2), along with two known lignan glycosides, (7 R ,8 R ,8′ S)-glaberide I 4- O - β -D-glucopyranoside (3) and (7 S ,7′ S ,8 R ,8′ R)-4,4′-dihydroxy-3,5,3′,5′tetramethoxy-7,9′:7′,9-diepoxylignane-4- O - β -D-glucopyranosyl-(1→4)- O - β -D-glucopyranoside (4) were isolated from the roots of Securidaca inappendiculata Hassk. The elucidation of their structures was based on the information of 1D, 2D NMR, HRESIMS, ECD, and the comparisons to published data. In addition, compounds 1 and 2 were evaluated for the anti-inflammatory activity against NO induced models. [ABSTRACT FROM AUTHOR]

This study demonstrates the successful use of CO 2 as versatile carbonation agent for the synthesis of 5-membered and 6-membered bicyclic glycocarbonates from methyl α- d -mannopyranoside (MDM) and methyl α- d -galactopyranoside (MDG). On the one hand, these two sugars were cyclized into 5-membered glycocarbonates by mere reaction of CO 2 with their hydroxyls either at cis-2,3 or cis-3,4 positions and without resorting to phosgene or its derivatives. The reactivity of the obtained 5-membered cyclic glycocarbonates were further tested with hexyl- and dodecyl amine. The self-assembling behavior of the formed alkyl glycosides in water was investigated and characterized by transmission electron microscope (TEM). On the other hand, secondary hydroxyls at 2- and 3- positions in MDM and MDG were first protected by a ketal group and by two ether, respectively before subjecting their respective 6-position hydroxyl to bromination. Their respective 6-bromo and 4-hydroxyl functions were subsequently reacted in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and CO 2 . The resulting 6-membered cyclic glycocarbonates were then polymerized using 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) or DBU as organocatalyst. All the synthesized 5- and 6-membered cyclic glycocarbonates and polyglycocarbonates were thoroughly characterized by FT-IR, 1 H, 13 C NMR and MALDI-ToF and Gel Permeation Chromatography (GPC). [ABSTRACT FROM AUTHOR]

A new lignanamide ( 1 ) and a new coumaroylamino glycoside derivative ( 2 ) were isolated and identified from hemp ( Cannabis sativa L.) seed along with eighteen known compounds ( 3-20 ), eight ( 9 , 10 , 14 - 18 , 20 ) of which were isolated for the first time from hemp seed. Their anti-neuroinflammatory activity on LPS (lipopolysaccharide)-induced BV2 microglia cells was evaluated. Compounds 1 , 2 , 5 - 9 , 12 , 13 , 15 - 17 , 19 and 20 exhibited significant inhibitory effects on TNF-α release from LPS-induced BV2 microglia cells, especially the new glucoside 2 . The results laid a solid foundation for additional research on hemp seed related to its value against neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

The stilbene compound resveratrol was glycosylated to give its 4′-O-β-D-glucoside as the major product in addition to its 3-O-β-D-glucoside by a plant glucosyltransferase fromPhytolacca americanaexpressed in recombinantEscherichia coli. This enzyme transformed pterostilbene to its 4′-O-β-D-glucoside, and converted pinostilbene to its 4′-O-β-D-glucoside as a major product and its 3-O-β-D-glucoside as a minor product. An analysis of antioxidant capacity showed that the above stilbene glycosides had lower oxygen radical absorbance capacity (ORAC) values than those of the corresponding stilbene aglycones. The 3-O-β-D-glucoside of resveratrol showed the highest ORAC value among the stilbene glycosides tested, and pinostilbene had the highest value among the stilbene compounds. The tyrosinase inhibitory activities of the stilbene aglycones were improved by glycosylation; the stilbene glycosides had higher activities than the stilbene aglycones. Resveratrol 3-O-β-D-glucoside had the highest tyrosinase inhibitory activity among the stilbene compounds tested. Synthesis and evaluation of stilbene glucosides. [ABSTRACT FROM PUBLISHER]

Three new compounds, i.e. 1-[2-(5-hydroxymethyl-1 H -pyrrole-2-carbaldehyde-1-yl)ethyl]-1 H -pyrazole ( 1 ), 1-({[5-(α- d -galactopyranosyloxy)methyl]-1 H -pyrrole-2-carbaldehyde-1-yl}-ethyl)-1 H -pyrazole ( 2 ), and (4-hydroxyphenyl)methanol 4-[β- d -apiofuranosyl(1→2)- O -β- d -glucopyranoside] ( 3 ), were isolated from an extract of watermelon seeds. Compounds 1 and 2 were pyrazole-alkaloids with a pyrrole ring. This is the first study to show compounds with pyrrole and pyrazole rings in a molecule isolated from natural products. In the evaluation for melanogenesis inhibitory, compound 1 exhibited modest inhibitory activity on melanogenesis without cytotoxicity. Meanwhile compound 2 showed some inhibitory activity accompanied by some cytotoxicity. [ABSTRACT FROM AUTHOR]

The article discusses the synthesis of several stilbenoids including glucosylated resveratrol, pterostilbene and piceatannol, and their 2,2- diphenyl-l-picrylhydrazyl free-radical-scavenging and radicalscavenging activities. Topics discussed include inhibitory activity among the stilbene glycosides, phosphodiesterase inhibitory activity, and neuroprotective activity.

The article presents a study which investigates the aroma composition and characteristics of cocoa tea. The study involves a sensory evaluation performed by 11 females by a 10-cm linear scale which uses corresponding samples from Camellia sinensis such as cocoa oolong tea, green tea, and black tea. The study shows that the aroma quality of fermented cocoa tea is similar to traditional high-grade oolong tea and black tea, therefore mass production and consumption in the market are possible.

The article discusses the aspects of digestion and absorption of Siraitia grosvenori Triteropenoids in rats. Researchers administered mogroside V, a penta-glucose-conjugated mogroside and the main sweetening component of Siraitia, to rats. They observed that most of the mogroside were degraded by the digestive enzymes and intestinal microflora, which was excreted in the feces as aglycone.

The article presents a study that characterizes glycosynthase mutant derived from glycoside hydrolase family 10 xylanases. Four xylanases were converted to glycosynthases by substituting the nucleophillic glutamic acid residues with glycine, alanine and serine. The glycosynthase reactions catalyzed by the glycosynthase mutants 10 xylanases were analyzed using xylobiosyl fluoride as the donor and xylooligosaccharides as acceptors to investigate the affinities of their positive subsites.