Insights To Biological Activity Of Momordica Grosvenori Saponin And Its Optimal Encapsulation

The fruit Momordica grosvenori which an herbaceous perennial plant contains large saponin with many biological activities.However,saponin from Momordica grosvenori often is instability when environments change.Therefore,this study was designed to deal with some bioactivities of Momordica grosvenori saponin as well as encapsulation parameters able to keep its activity.Firstly,different indexes was used to evaluate the change of saponin antioxidant activity and its hypoglycemic activity.Then parameters responsible for the encapsulation of Momordica grosvenori saponin were optimized.The structure of Momordica grosvenori saponin's capsules and the released rate of saponin were evaluated.The following are main results.1.Momordica grosvenori saponin showed good antioxidant activity.Its Trolox equivalent of eliminating ABTS,DPPH and ·OH radicals were 26.50?mol/g,3.58?mol/g and 14.08?mol /g,respectively.It had a good inhibition towards ?-glucosidase,and its semi-inhibition concentration was 3.477mg/ml,with reversible and mixed inhibition type.2.Sodium alginate was selected as suitable inner membrane material by pre-trials.Factors affecting the encapsulation of Momordica grosvenori saponin were carried out using cross-linked extrusion.Sodium alginate concentration,capsule formation ratio and dosage ratio were selected as the important factors for response surface experiments.The optimal parameters for encapsulating Momordica grosvenori saponin was stirring time of 30 mins,stirring speed of 1000r/min,4mg/m L concentration of chitosan,10mg/m L concentration of calcium chloride,20.8mg/m L concentration of sodium alginate,1:4 capsule formation ratio and 1:3 dosage ratio.In this case,80.25% Momordica grosvenori saponin was encapsulated averagely.3.The structure of sodium alginate would be changed by encapsulating Momordica grosvenori saponins.The capsules of Momordica grosvenori saponin were treated with three drying methods.Some differences in the encapsulated Momordica grosvenori saponin were observed between natural drying and freeze-drying.Wet capsules of Momordica grosvenori saponin looked like compact,white,translucent,tough,uniform and spherical in morphology with an average particle size of 1687?m;its ambient-drying capsules were compact,yellow,rigid,crystal-translucent and hard with an average particle size of 842.1?m;and its freeze-dried capsules were loose,white opaque,brittle,near-spherical or ellipsoidal and fragile with an average particle size of 1018?m.However,the surface of the capsules was damaged during drying process,resulting in the decrease of encapsulation efficiency.In-vitro test showed that wet capsules provided a better protection for Momordica grosvenori saponin to challenge gastrointestinal environment.More than 60% Momordica grosvenori saponins showing a good biological activity tolerated the harsh conditions.The capsules Momordica grosvenori saponin which were dried treatment had a poor ability to challenge gastrointestinal environment,although there was no significant difference in the encapsulants of saponin.The residual activity of Momordica grosvenori saponin in capsules,after treated with gastric acid,was only 22.9% for ambient drying and 17.9% for freeze-drying.In conclusion,appropriate technology should be screened for preserving the activity of Momordica grosvenori saponin,thus improving its stability.