Preparation of core-shell hordein/pectin nanoparticles as quercetin delivery matrices: Physicochemical properties and colon-specific release analyses.

Quercetin (Que) is a hydrophobic flavanol that has the potential to prevent colon diseases. This study aimed to design hordein/pectin nanoparticle as a colon-specific delivery system for quercetin. The encapsulation efficiency, physicochemical stability and release properties of the nanoparticles were estimated. The FTIR and secondary structure analysis indicated that hydrogen bonds, hydrophobic interactions and electrostatic attractions were formed in the quercetin-loaded hordein/pectin nanoparticles (Que-hordein/pectin NPs). In comparison to Que-hordein NPs, Que-hordein/pectin NPs exhibited better colloidal stability (physical, UV light, heating and salt). Furthermore, the release properties studies showed that pectin coating restrained the premature release of Que from hordein NPs in gastric fluid and intestinal fluid. In-vitro release, when the Que-hordein/pectin NPs were exposed to simulated colonic fluid (SCF) for 6 h, quercetin was greatly released from the hordein/pectin NPs (15.29 ± 1.17% - 80.60 ± 1.78%). In-vivo release, the concentration of Que (µg/g) in Que-hordein/pectin NPs was 2.18 times higher than Que-hordein NPs in colon tissue after 6 h of oral administration. This study suggests that Que-hordein/pectin NPs have promising applications in the specific delivery and release of quercetin to the colon.

In vitro and In vivo digestion comparison of bee pollen with or without wall-disruption.

BACKGROUND: Bee pollen is considered as a treasure trove of human and animal nutrients as a result of its extensive nutritional and therapeutic properties. However, the sophisticated pollen wall can largely limit the digestibility and bioavailability of these nutrients. RESULTS: An ultrasonication and high shear technique was used to break the walls of five species of bee pollen, including rape bee pollen, lotus bee pollen, camellia bee pollen, wuweizi bee pollen and apricot bee pollen. We compared the digestibilities of bee pollen with or without wall-disruption. After in vitro and in vivo digestion, unbroken bee pollen grains were still intact and the fragments of wall-disrupted bee pollen still remained as fragments. Mouse in vivo digestion results suggested that the wall-disrupted bee pollen was more easily emptied from the gastrointestinal tract than unbroken bee pollen. After dynamic in vitro digestion, the digestibilities of protein and crude fat in wall-disrupted bee pollen significantly increased to more than 80%; similarly, the release rates of amino acids and reducing sugars in all wall-disrupted samples were almost 1.5 and 2 times as much as those of unbroken samples. CONCLUSION: Based on the results obtained in the present study, we strongly recommend that bee pollen should be wall-disrupted. © 2020 Society of Chemical Industry.

In vivo bioavailability of polyphenols from grape by-product extracts, and effect on lipemia of normocholesterolemic Wistar rats.

BACKGROUND: The direct use of phenolic extracts from grape by-products can be useful when formulating functional food to improve consumer health. The use of phenolic extracts instead of pure polyphenols as an ingredient is relevant in this context. The present study investigated the bioavailability and absorption of polyphenols from grape by-product extracts and their health effect on cholesterolemia, by adding the extract (GE) to Wistar rats diet (50 g kg-1 ) in vivo. RESULTS: GE caused the appearance of (+)-catechin, myricetin and quercetic acid in plasma and liver. (+)-Catechin was the most abundant compound (6 µg mL-1 in plasma and 0.7 µg mg-1 protein in liver), whereas no phenolic compounds were detected in plasma or liver in the control group. Similarly, 3,4-hydroxyphenylacetic, a major product of polyphenol digestion, was detected in the plasma, liver and urine of the GE-group only. GE-group had significantly lower cholesterol level and lower total cholesterol/high-density lipoprotein ratio in plasma. Total bile acid content significantly increased in fecal matter after 24 h administration of the GE-enriched diet. CONCLUSION: Grape extract polyphenols are partially bioavailable and showed improvement in lipid metabolism. Thus, the results suggest that GE is promising as a functional ingredient in the prevention of hypercholesterolemia. © 2018 Society of Chemical Industry.