Curcumin loading and colon release of pectin gel beads: Effect of different de-esterification method

Low methoxyl citrus pectin (LMP) de-esterified from high hydrostatic pressure assisted enzymatic (HHP-pectin) and two other traditional methods was characterized, and curcumin-pectin calcium gel beads were prepared to study curcumin-loading and colon-targeted delivery abilities. It was found there was no significant difference among different LMP on amorphous structure, while significantly higher Rha/GalA ratio of HHP-pectin indicated higher rhamnogalacturonan Ⅰ (RG-I) proportion and branching extent. Curcumin was well embedded in LMP beads with improved stability. HHP-pectin beads showed significantly higher hardness, chewiness and encapsulation efficiency, while lower swelling ratio. Moreover, in vitro simulated digestion showed gel beads can deliver curcumin to colon and inhibit premature release. HHP-pectin beads could release curcumin more quickly in colon, probably because of differences on texture properties, which may be depended on molecular structure. Thus, LMP especially HHP-pectin calcium gel as colon-targeted delivery system for curcumin may have potential application in function food and drug delivery.