Structural diversity requires individual optimization of ethanol concentration in polysaccharide precipitation

Stepwise ethanolic precipitation of sugar beet pectins from the acidic extract

“…Among them, the ethanol concentration used for pectin precipitation is responsible for interrupting the interactions between pectins and solvent molecules. For obtaining a complete precipitation of pectins, in most cases, an alcohol-to-extract volume ratio of 3:1 is used to give a final ethanol concentration above 70%, which agrees well with the literature data (70-80%) commonly-used for precipitating natural polysaccharides (Xu et al, 2014).…”

Effects of low-molecular weight alcohols on bacterial viability

“…Interestingly, the alcohols inhibited the growth of K. pneumoniae, a bacterium that is part of the same family as E. coli, in a concentration of about 3% V/V, but the bactericidal effect appeared at higher concentrations. The definitory structure for this bacterial behavior is the polysaccharide capsule, on which the alcohols exert a precipitation effect, A B but the intensity of this effect is dependent on the concentration of the alcohol (17). Moreover, the capsule provides protection against desiccation (18).…”

Immunomodulating Activity of Crude Polysaccharide from Inonotus obliquus Sclerotia by Fractionation including MeOH Reflux

“…Meanwhile, because the bioactivities of polysaccharide are affected significantly by structural features and molecular weights, the isolation of a specific polysaccharide is essential for the studies of physiological activity of polysaccharides. Xu et al (2014) suggested the possibility of separating fractions of different structures from the starting mixture using appropriate alcohol concentration. The stepwise ethanolprecipitation procedure is more selective with respect to pectin structural features and surface properties than the one-step ethanolic precipitation (Guo et al 2016).…”

“…30, No. 1(2017) Immunomodulating polysaccharide from I. obliquus by MeOH reflux 99 Ethanol precipitation is one of the most widely used methods for preparing natural polysaccharides, in which ethanol concentration significantly affects the yield of total sugar, is usually set at 70-80% (Xu et al 2014). Only in the last few years, polysaccharides have been fractionated by stepwise ethanol precipitation, replacing almost all of the purification protocols that include at least one such step (Teleman et al 2000).…”