Investigation on physicochemical properties and biological activities of yeast nanosized β-glucan

Yeast β-glucan is a kind of multifunctional polysaccharide. In this study, granular β-glucan was made from the cell wall of Saccharomyces cerevisiae using hot water extraction, and its sizes were reduced to the nano level by high pressure homogenization. The obtained nanosized β-glucan was evaluated for its physicochemical properties and in vitro biological activities. The average particle size of nanosized β-glucan was 83.15 nm and zeta potential was −20.1 mV. The analysis by Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction indicated that the basic chemical structure of yeast β-glucan was not changed after nano-reduction with homogenization treatment. The suspension stability of nanosized β-glucan in water was greatly improved compared with native β-glucan. Nano-reduction made the viscosity, swelling capacity, oil-holding capacity and emulsifying activity of nanosized β-glucan obviously increase, but decreased its water-holding capacity. The nanosized β-glucan exhibited significantly enhanced antioxidant, in vitro hypolipidemic, in vitro hypoglycemic and anticancer activities in comparison to native, which might be duo to the particle size in the nano level. It is concluded that the nanosized β-glucan had significantly improved the nutraceutical properties. • Basic chemical structure of yeast β-glucan was not changed after nano-reduction • The oil-holding capacity of nanosized β-glucan increased by 42.9% • The nanosized β-glucan exhibited significantly enhanced antioxidant activity • α-glucosidase inhibitory activity of nanosized β-glucan was 90.8% • Treatment with nanosized β-glucan decreased the viability of Hela cells to 55.52%