Add time:07/28/2019         Source:sciencedirect.com

The aqueous extract of the edible green microalgae Chlorella pyrenoidosa is of interest because of its immunostimulatory activity. Some components in the extract have been identified previously, namely a unique type of arabinogalactan and a galactofuran. Further fractionation of this extract was accomplished by treating the aqueous solution of the fraction precipitated by addition of 1.5 vol of 95% ethanol with cetyltrimethylammonium bromide. The residue obtained by concentration of the supernatant was fractionated further by anion-exchange chromatography and size-exclusion chromatography on Sephadex G-100. Two fractions from the latter column were retained, of which one was a starch-like α-(1→4)-linked d-glucan with some α-(1→6) branches, and the other contained a starch plus a mixture of β-(1→2)-d-glucans. ESI mass spectrometry was used to show that the mixture contained both cyclic and linear β-(1→2)-d-glucans in a cyclic:linear ratio of 64:36, based on intensities of mass spectral peaks. For the cyclic β-(1→2)-d-glucans, ring sizes ranged from 18 to 35 monosaccharides with the ring containing 21 glucose units (54% of the cyclic glucans) being greater than three times more abundant than the next most abundant component, the ring containing 22 glucose units (15%). No rings containing 20 glucose units were present. This is the first observation of cyclic β-(1→2)-d-glucans in algae, as far as we are aware. For the linear β-(1→2)-d-glucans, the component containing 20 glucoses was most abundant (35% of the linear glucans), while the component containing 21 glucose units was the next most abundant (17%). These relatively low-molecular-weight glucans had low immunostimulatory activity.

We also recommend Trading Suppliers and Manufacturers of cyclic beta(1-2)glucan (cas 116243-01-7). Pls Click Website Link as below: cas 116243-01-7 suppliers