Vitexin-rhamnoside encapsulated with zein-pectin nanoparticles relieved high-fat diet induced lipid metabolism disorders in mice by altering the gut microbiota.

This study aimed to investigate the modulatory effects of Vitexin-rhamnoside (VR) and Zein-VR-pectin nanoparticles (VRN) on lipid metabolism disorders induced by high-fat diet (HFD). The ingestion of VR or VRN attenuated dyslipidemia and fat accumulation in HFD mice, and improved intestinal dysbiosis by regulating the relative abundance of dominant bacteria, alleviating chronic inflammation and hepatic injury in HFD mice. The intervention effect of VRN was significantly higher than that of VR. After fecal microbiota transplantation (FMT) treatment, the fecal microbiota of VRN-treated donor mice significantly attenuated the symptoms associated with hyperlipidemia, confirming that VRN ameliorates HFD-induced disorders of lipid metabolism by modulating the gut microbiota, especially increasing the abundance of Rombousia and Faecalibaculum. Overall, VRN can regulate the gut microbiota and thus improve lipid metabolism. The present study provided new evidence that nanoparticles enhance the bioavailability of food bioactive ingredients.

Guanosine-based Hydrogel Integrating Photothermal Effect of PDA-AuNPs through Dynamic Borate Bond for Photothermal Therapy of Cancer.

Photothermal therapy (PTT) has drawn extensive attention owing to its noninvasive and great tissue penetration depth. However, the physical encapsulation of photothermal agents may lead to their rapid release. Dual-functional hydrogel systems that integrate functions and carriers can potentially solve this problem. In this work, we successfully developed a dual-functional guanosine(G)-based hydrogel integrating the photothermal effect and localized delivery by introducing dynamic borate ester utilizing the photothermal property of PDA-AuNPs and the self-assembly ability of G. Both in vitro and in vivo results confirmed that the GBPA hydrogel not only exhibited excellent photothermal toxicity, stability, injectability, and biocompatibility, but also possessed high photothermal antitumor activity. These results suggested that the GBPA hydrogel could be used as a dual-functional hydrogel integrating photothermal effect and localized delivery in one system, which would possibly provide a new opportunity for the design of new dual-functional hydrogels for highly efficient cancer therapy.

Preparation and characterization of highly lipophilic modified potato starch by ultrasound and freeze-thaw treatments.

In order to explore the potential application of combined physical treatment in producing highly lipophilic modified starch, the effects of ultrasound combined with freeze-thaw treatment on the microstructure and physicochemical properties of potato starch were investigated. The samples treated by combined treatment had the roughest structure and the oil adsorptive capacity value increased from 59.62% (native starch, NS) to 80.2% (7 cycles of ultrasound-freeze-thaw treatment starch, 7UT-FTS). Compared to NS, the crystalline type and chemical groups of modified starches did not change, but the relative crystallinity, enthalpy change, and paste viscosity decreased to varying degrees, while the gelatinization temperature increased. The digestibility of raw modified starch was higher than that of NS, but this phenomenon disappeared after gelatinization. 7UT-FTS showed better resist-digestibility than NS after encapsulating oil. Hence, this would be an efficient and environmentally friendly way to produce modified starch with safety, highly lipophilic and heat resistance.

Effect of repeated retrogradation on structural characteristics and in vitro digestibility of waxy potato starch.

The effects of repeated retrogradation (RR) treatment on the structural characteristics and in vitro digestibility of waxy potato starch were investigated. The cycling times of RR ranging from 1 to 5 were designated as RR-1, RR-2, RR-3, RR-4, and RR-5, respectively. A maximum SDS content (40.41%) was obtained by RR-2 treatment with the time interval of 48h. RR-2-treated starch product exhibited a narrower melting temperature range, a higher onset temperature and a lower melting enthalpy compared with RR-1 treatment. Compared with native starch, X-ray diffraction patterns of treated starches were altered from B-type to C-type. The variation in relative crystallinity of RR-treated starch products was consistent with that in melting enthalpy. Moreover, compared with RR-1-treated starch, a large number of cavities were observed on the surface of RR-2-treated starch product with a time interval of 48h, whereas more smooth regions were found on the surface of RR-5-treated starch product. This study suggested that structural changes of waxy potato starch treated with different cycling times of RR significantly affected the digestibility.

Effect of temperature-cycled retrogradation on in vitro digestibility and structural characteristics of waxy potato starch.

The effects of temperature-cycled retrogradation treatment on the structural characteristics and in vitro digestibility of waxy potato starch were investigated in this study. The results showed that the maximum yield of slowly digestible starch (SDS) in waxy potato starch reached 38.63% by retrogradation treatment under temperature cycles of 4/25°C for 3 days with an interval of 24h. The starch products prepared under the temperature cycles of 4/25°C exhibited a narrower melting temperature range (Tc-To), a higher melting enthalpy (ΔH) and a higher IR absorbance ratio (1047cm(-1)/1022cm(-1)) than that prepared at a constant temperature of 25°C. Compared to native starch, X-ray diffraction pattern of treated starch was altered from B-type to C-type. Furthermore, the relative crystallinity of the starch products prepared under temperature-cycled retrogradation was the highest. This study suggests that more imperfect crystallites are formed in the crystalline matrix under temperature-cycled retrogradation, resulting in a high yield of SDS.