The preparation of gel microspheres based on physical crosslinking by β-glucan isolated from Poria cocos residues and the powder characteristics.

Recently, polysaccharide based gel microspheres have become popular in biomedical fields due to their excellent biocompatibility and degradability. β-glucan, a kind of bioactive antitumor and immune polysaccharide, also shows great potentials in the microsphere preparation. However, most reported β-glucan based microspheres usually facing problems, including complicated components or procedures, and toxic chemical modification. In this work, we successfully obtained gel microspheres (PCPA-MS) only composed of β-glucans, with size between 8 and 26 μm, through hydrogen bonding by emulsion method. Moreover, β-glucan (PCPA) used in this work was extracted from the discarded medicinal residue with yield of 59 % after boiling Poria cocos. This is an important part of the recycling of traditional Chinese medicine to achieve green and sustainable development. In addition, the optimal construction conditions of PCPA-MS was concluded as 1 mol/L hydrochloric acid, 10 mg/mL PCPA, Span85: PCPA = 1:5 (m/v), rotational speed of 500 rpm, and isooctane: PCPA = 5:2 (m/v). Moreover, the prepared PCPA-MS displayed excellent powder characteristics, including good stability, strong water/oil absorption abilities, better adhesion rate and hiding power. Therefore, this work provide a simple, green and economical method to construct microspheres, which have promising application prospects in the fields of food, cosmetics, and even pharmaceuticals.