Spiral-Dextrin Complex Crystals: Efficient Approach for Colon-Targeted Resveratrol Delivery.

In this work, spiral dextrin/resveratrol (SD/Res) crystal, a new colon-specific drug-delivery system, was established by a novel method of encapsulation and cocrystallization to improve the antidigestion ability compared with the SD/Res inclusion complex (SD/Res IC) prepared by encapsulation and coprecipitation. X-ray diffraction (XRD) and scanning electron microscopy (SEM) revealed that the SD/Res crystal formed a more regular and perfect crystallite than SD/Res IC. Moreover, the encapsulation ability and thermostability of the SD/Res crystal were enhanced as the chain length of SD was increased. In vitro digestion indicated that SD/Res IC merely achieved small intestine-targeted release of resveratrol, while the SD/Res crystal could act as a colon-specific delivery system to protect resveratrol from degradation by gastric acid and pancreatic enzymes. The SD-1/Res crystal presented much higher thermal stability and stronger gastrointestinal stability than other SD/Res crystals and SD/Res ICs, which facilitated its application as a novel colon-target delivery system for resveratrol.

Stability of trypsin inhibitor isolated from potato fruit juice against pH and heating treatment and in vitro gastrointestinal digestion.

Potato trypsin inhibitor (PTI) was obtained from imitated potato wastewater through a sustainable method of sequential acid precipitation, salting out, and ultrafiltration. PTI had a favorable inhibition with the low IC50 of 6.861 ± 0.107 mg/L. To explore stability of PTI against pH and heating treatment, PTI secondary structure was investigated by circular dichroism and inhibition was determined using the BAPNA method. The results indicated that PTI exerted a certain heat resistance and excellent stability over a wide pH range. Also, correlation analysis displayed ß-sheet and ß-turn contents of PTI had a positive correlation with inhibition, whereas α-helix and random coil contents were negatively correlated with inhibition. During in vitro digestion, the limited loss rate of activity (29.28%) and degree of hydrolysis (24.39%) suggested that PTI presented sufficient resistance to gastrointestinal digestion. These findings would extend beneficial hints to convert potato wastewater by-product into the potential anti-obesity ingredient in future.