Dual-crosslinked soy protein-soy hull polysaccharide liposomal gels for targeted lutein delivery and controlled release in vitro and in vivo: Impact of soy hull polysaccharide concentration.

Soybean protein isolate (SPI) and soy hull polysaccharide (SHP) were combined with lutein liposomes (Lu-lip) to form an SPI-SHP lutein liposome gel (SPI-SHP Lu-lip gel) through dual-induced cross-linking using Ca2+ and TGase. With increasing SHP concentration, the formation of a stable composite gel structure resulted in a gradual improvement in the water-holding capacity (WHC) of the SPI-SHP Lu-lip gels. At 3.0 % SHP concentration, the encapsulation efficiency reached 91.83 %, forming a tightly stacked, strong reticular structure upon dual-induced cross-linking by Ca2+ and TGase. SPI-SHP Lu-lip gels suppressed the release of Lu-lip during the gastric phase and enhanced its targeted release in the intestinal phases, owing to the protective impact of the gel's dense network structure on lutein. Particularly, the composite gel with 3.0 % SHP demonstrated better release and achieved a bioavailability of 36.38 %. which can act as a controlled-release system, effectively protecting and delivering sensitive bioactive compounds or nutrients.