Effects of microfluidization with ionic liquids on the solubilization and structure of β-D-glucan

In order to enhance the solubility of yeast beta-D-glucan and enlarge the applicable area, we investigated dynamic high pressure microfluidization (DHPM) treatment with ionic liquids as solvent to prepare water-soluble yeast beta-D-glucan (WSG). The solubility of beta-D-glucan was greatly impacted by the pressure of DHPM, residence time, and ratio of beta-D-glucan and EmimAc. The yield of WSG reached 79.25 % (w/w) with the water solubility of 72.50 % (w/w). The DHPM treatment did not destroy the ionic liquid structure therefore the ionic liquids could be recycled. FTIR and C-13 NMR spectrum results showed that WSG was the polysaccharides with (1 -> 3)-beta-D-glycosidic bonds, after modification, the hydrogen bonding was destroyed. The chain conformation of WSG in 0.1 M NaNO3 aqueous solutions at 25 degrees C were studied by laser light scattering and viscometry. The Mark-Houwink equation was established to be [eta] = 2.09 x 10(-2) M-W(0.63) (cm(3) g(-1)). According to the conformational parameters calculated from wormlike cylinder model, WSG existed as semi-stiff chain in aqueous solution. (C) 2015 Published by Elsevier B.V.