Site-directed mutagenesis and a comparative characterisation of the kinetic parameters, pH dependency of activity and thermal stability of mutant and wild-type enzymes have been used in association with crystallographic analysis to delineate the functions of several active site residues in a novel glycoside hydrolase family 8 xylanase. Each of the residues investigated plays an essential role i...

Three new sesquiterpenes, (2R,3S,5R)-2,3-epoxy-6,9-humuladien-5-ol-8-one (1), (2R,3R,5R)-2,3-epoxy-6,9-humuladien-5-ol-8-one (2), and (5R)-2,6,9-humulatrien-5-ol-8-one (3), and two new flavonol glycosides, kaempferol-3-O-(2,3-di-O-acetyl-alpha-l-rhamnopyranoside) (4) and kaempferol-3-O-(2,3,4-tri-O-acetyl-alpha-l-rhamnopyranoside) (5), were isolated from the EtOAc-soluble fraction of the water ...

A new withanolide glycoside, 17beta-hydroxy-14, 20-epoxy-1-oxo-[22R]-3beta-[O-beta-D-glucopyranosyl]-witha-5, 24-dienolide (1), has been isolated from the whole plant of Physalis peruviana. Its identity was determined using a combination of spectroscopic data including 2D NMR techniques and chemical transformations.

− A new quercetin 3-O-trisaccharide was isolated from the leaves of Rubus crataegifolius (Rosaceae). The structure of this compound was determined as quercetin 3-O-α-L-arabinofuranosyl-(1→ 2)-β-D-xylopyranosyl(1→ 2)-β-D-galactopyranoside on the basis of 2D-NMR spectroscopic data. This flavonol glycoside was isolated for the first time from a natural source.

India is sitting on a gold mine of well-recorded and traditionally well practiced knowledge of herbal medicine. General phytochemical screening of Citrus sinensis (Orange) belonging Rutaceae family revealed the presence of flavones glycoside. The aim of this study is to identify and characterize the bioactive principle compound (Hesperidin) from the dried peel of C. sinensis fruit. It has wide ...

Hesperetin (3',5,7-trihydroxy 4'-methoxyflavanone) and its glycoside hesperidin (hesperetin 7-rhamnoglucoside) in oranges have been reported to possess pharmacological effects related to anti-obesity. However, hesperetin and hesperidin have not been studied on suppressive effects on appetite. This study examined that hesperetin and hesperidin can stimulate the release of cholecystokinin (CCK), ...

In a preliminary note (Daglish & Wokes, 1948) it was shown that the 'apparent vitamin C' of the walnut (Juglan8 regia) (Wokes, Organ, Duncan & Jacoby, 1943) was probably a hydrojuglone derivative. The evidence for this was based upon the findings that solutions of the substance separated by chromatography showed an ultraviolet absorption curve similar to those of reduced acetoxyjuglone and ahyd...

Column chromatographic separation of a MeOH extract of the aerial parts of Saussurea triangulata led to the isolation of a new sesquiterpene glycoside 6, together with three quinic acid derivatives, two phenolics, two sesquiterpene glycosides and two flavonoids. The new compound 6 was identified as amarantholidol A glycoside by spectroscopic and chemical methods.

From the leaves and branches Barnettia kerrii, two verbascoside derivatives (6"-O-acetylverbascoside and 4"'-O-acetylverbascoside), as well as two phenolic glycosides (khaephuosides A and B) were isolated together with 15 known compounds. The structural elucidations were based on analyses of spectroscopic data.