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The diversity of monosaccharides and glycosidic linkages of extracellular polysaccharide (EPS) of high molecular weight were studied in strains morphologically assigned to the genus Ankistrodesmus. EPSs of seven strains were similar in both monosaccharides and glycosidic linkages, but showed exclusive characteristics or enough differences in proportions to distinguish strains. Fucose, glucose, rhamnose, mannose and galactose occurred in relatively high percentages in all strains. The strain CCMA-UFSCar 423, excluded from the genus Ankistrodesmus by the molecular marker tufA, was the only one containing galacturonic acid. Arabinose was found only in one A. densus strain (CCMA-UFSCar 239). The species A. densus and A. stipitatus, which are known to have, respectively, stable mucilaginous capsules and pads in aqueous media, presented high percentages of the hydrophobic fucose and rhamnose on their polysaccharides. However, the strain CCMA-UFSCar 83, the only non-colonial A. densus, had low proportions of rhamnose. We also found variations in glycosidic linkages, and some of them were specific to one strain (e.g. 1-3 glucose in A. stipitatus). Conversely, the absence of common linkages was noteworthy for the strain outside the Ankistrodesmus clade, the CCMA-UFSCar 423. The data revealed important diversity in monosaccharides and linkages of the EPS within a single microalgae genus, and an important intraspecific diversity using a single growing condition. These differences could be useful as potential chemotaxonomic tools to help discriminating the Ankistrodesmus genus or species, but also for future studies on intraspecific diversity within the genus. Moreover, the results show the relevance of studying and conserving closely related strains to preserve biodiversity. The diverse composition of high molecular weight EPSs shows a great potential for prospecting EPSs of economic interest. [ABSTRACT FROM AUTHOR]

Abstract An ethnopharmacological survey was carried out to collect information on the use of seven medicinal plants in rural areas in the nearby regions of Bamako, Mali. The plants were Opilia celtidifolia, Anthocleista djalonensis, Erythrina senegalensis, Heliotropium indicum, Trichilia emetica, Piliostigma thonningii and Cochlospermum tinctorium About 50 medical indications were reported for the use of these plants in traditional medicine. The most frequent ailments reported were malaria, abdominal pain and dermatitis. The highest number of usages was reported for the treatment of malaria (22%). The majority of the remedies were prepared from freshly collected plant material from the wild and from a single species only. They were mainly taken orally, but some applications were prepared with a mixture of plants or ingredients such as honey, sugar, salt, ginger and pepper. Decoction of the leaves was the main form of preparation (65%) and leaf powder was mostly used for the preparation of infusions (13%). The part of the plants most frequently used was the leaves. There was a high degree of informant consensus for the species and their medicinal indications between the healers interviewed. The results of this study showed that people are still dependent on medicinal plants in these rural areas of Mali.

A Western lifestyle with low physical activity and a diet rich in sugar, fat and processed food contribute to higher incidences of diabetes and obesity. Enhanced glucose uptake in human liver cells was observed after treatment with phenolic extracts from different Nordic berries. All berry extracts showed higher inhibition against α-amylase and α-glucosidase than the anti-diabetic agent acarbose. Total phenolic content and phenolic profiles in addition to antioxidant activities, were also investigated. The berries were extracted with 80% methanol on an accelerated solvent extraction system (ASE) and then purified by C-18 solid phase extraction (SPE). Among the ASE methanol extracts, black chokeberry, crowberry and elderberry extracts showed high stimulation of glucose uptake in HepG2 cells and also considerable inhibitory effect towards carbohydrate hydrolyzing enzymes. SPE extracts with higher concentrations of phenolics, resulted in increased glucose uptake and enhanced inhibition of α-amylase and α-glucosidase compared to the ASE extracts. Crowberry and cloudberry were the most potent 15-lipoxygenase inhibitors, while bog whortleberry and lingonberry were the most active xanthine oxidase inhibitors. These results increase the value of these berries as a component of a healthy Nordic diet and have a potential benefit against diabetes. [ABSTRACT FROM AUTHOR]

Type 2 diabetes (T2D) is manifested by progressive metabolic impairments in tissues such as skeletal muscle and liver, and these tissues become less responsive to insulin, leading to hyperglycemia. In the present study, stimulation of glucose and oleic acid uptake by elderflower extracts, constituents and metabolites were tested in vitro using the HepG2 hepatocellular liver carcinoma cell line and human skeletal muscle cells. Among the crude extracts, the 96% EtOH extract showed the highest increase in glucose and oleic acid uptake in human skeletal muscle cells and HepG2-cells. The flavonoids and phenolic acids contained therein were potent stimulators of glucose and fatty acid uptake in a dose-dependent manner. Most of the phenolic constituents and several of the metabolites showed high antioxidant activity and showed considerably higher α-amylase and α-glucosidase inhibition than acarbose. Elderflower might therefore be valuable as a functional food against diabetes. [ABSTRACT FROM AUTHOR]

The root bark, stem bark and leaves of Terminalia macroptera were sequentially extracted with ethanol, 50% ethanol-water, and 50 °C and 100 °C water using an accelerated solvent extractor. Ten bioactive purified polysaccharide fractions were obtained from those crude extracts after anion exchange chromatography and gel filtration. The polysaccharides and their native extracts were characterized with respect to molecular weight, chemical compositions and effects in the complement assay. The chemical compositions showed that the polysaccharides are of pectic nature. The results indicated that there was no great difference of the complement fixation activities in the crude extracts from the different plant parts when extracting with the accelerated solvent extraction system. The purified polysaccharide fractions 100WTSBH-I-I and 100WTRBH-I-I isolated from the 100 °C water extracts of stem and root bark respectively, showed the highest complement fixation activities. These two fractions have rhamnogalacturonan type I backbone, but only 100WTSBH-I-I contains side chains of both arabinogalactan type I and II. Based on the yield and activities of the fractions studied those from the root bark gave highest results, followed by those from leaves and stem bark. But in total, all plant materials are good sources for fractions containing bioactive polysaccharides. [ABSTRACT FROM AUTHOR]