Biomedical subjects

Anne Berit Samuelsen

Publications and source records attributed to Anne Berit Samuelsen.

3 recordsLinked to original sources

PubMed2006

Antioxidant and 15-lipoxygenase inhibitory activity of rotenoids, isoflavones and phenolic glycosides from Sarcolobus globosus.

From Sarcolobus globosus, two rotenoids (villosinol and 6-oxo-6a,12a-dehydrodeguelin), one isoflavone (genistin) and four phenolic glycosides (vanillic acid 4-O-beta-d-glucoside, glucosyringic acid, tachioside and isotachioside) were identified for the first time from this species. Extracts and compounds from S. globosus were evaluated for their DPPH radical scavenging and 15-lipoxygenase (15-LO) inhibitory activities. All tested rotenoids were found to inhibit 15-LO, while they lacked DPPH radical scavenging effect.

Antioxidants↗

PubMed2006

Pectin isolated from white cabbage--structure and complement-fixing activity.

This study was done to investigate whether white cabbage contained polysaccharides with immunostimulatory activity using the complement-fixing test as an indicator. The main polysaccharide isolated was of pectin nature. Methanolysis and (13)C-NMR showed that the polymers consisted of highly esterified alpha-galactopyranoside (alpha-GalpA), significant amounts of alpha-arabinose furanoside (alpha-Araf), beta-Galp and lesser amounts of rhamnose in the pyranose form (Rhap) and xylose in the pyranose form (Xylp). Linkage analyses showed that the alpha-GalpA residues were mainly 1,4-linked with small amounts of 1,3,4-linkages. The alpha-Araf residues were mainly terminally (t)- and 1,5-linked, whereas beta-Galp was t-, 1,3-, 1,6-, and 1,3,6-linked. Positive Yariv reaction indicated polymers with arabinogalactan type 2 like structures. alpha-Rhap was mainly present as 1,2- and 1,2,4-linked residues and Xylp was t- and 1,4-linked. The molecular weight varied greatly and was from 10 to 150 kDa. Cabbage polymers had biological activity and this complement-fixing activity was greatly affected by hydrolytic removal of Araf from pectic side chains.

Arabinose↗

PubMed2005

Rotenoids and isoflavones from Sarcolobus globosus.

Sarcolobus globosus is a medicinal plant growing in mangrove forests in Asia. No constituents from this plant have been reported previously. From the diethyl ether extract of S. globosus a new rotenoid sarcolobin and a new isoflavone sarcolobone, as well as the previously known rotenoids tephrosin, 12aalpha-hydroxydeguelin, 11-hydroxytephrosin, 12a-hydroxyrotenone, 12aalpha-hydroxyrotenone, 6aalpha,12aalpha-12a-hydroxyelliptone, 6a,12a-dehydrodeguelin, 13- homo-13-oxa-6a,12a-dehydrodeguelin, the isoflavone barbigerone and a chromone 6,7-dimethoxy-2,3-dihydrochromone were identified. 6,7-Dimethoxy-2,3-dihydrochromone has not previously been reported as a natural product.

Apocynaceae↗