Akebia trifoliata fruits, a kind of popular edible berry in Asia, are widely consumed as daily fruits or functional foods. Our previous study found several bioactives from Akebia trifoliata pericarp extract (APE), and preliminarily investigated their anti-inflammatory activity. However, the underlying mechanism of APE for the observed anti-inflammatory effects is still unknown. Thus, the bioactive profiles and anti-inflammatory mechanism of APE were investigated by a combination of chemical assays: UPLC-LTQ-Orbitrap/MS technique, lipopolysaccharide (LPS)-induced RAW264.7 cells and DSS-induced mouse model. The results indicated that the phenolic acids and terpenoids are major bioactives of APE, which could inhibit the production of nitric oxide (NO) and prostaglandin E2 (PGE₂) by blocking the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in RAW264.7 cells as well as reduce the expression of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β), and suppress the phosphorylation of p-65, IκBα and mitogen-activated protein kinase (MAPKs including p38, ERKs, JNKs) proteins both in vitro and in vivo. Furthermore, APE treatment could regulate gut microbiota by increasing the richness of Rikenellaceae and Lactobacillaceae and reducing that of Lachnospiraceae and Ruminococcaceae. In summary, these findings clearly demonstrated that APE mitigates inflammation by restraining the production of cytokines through nuclear factor-κB (NF-κB) and MAPK signaling pathways, and altering gut microbiota, and therefore, this could be a potential functional food for the treatment and prevention of inflammatory bowel diseases.

Lutein, as a natural nutrient, has many benefits for human health. However, its poor chemical stability and low bioavailability limit the application of lutein in foods. The aim of this study is to design and develop rice protease hydrolysate (RPH)–carboxymethylcellulose (CMC) nanocarriers for efficient delivery of lutein. RPH–CMC nanoparticles were prepared by heating at a ratio of RPH to CMC of 4 : 1 and pH of 6.0 (70 °C, 20 min). The structure of the nanoparticles was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and transmission electron microscopy (TEM). In addition, the stability, in vitro release characteristics, anti-proliferation and drug absorption of lutein-loaded rice protein nanoparticles (Lut-R) and lutein-loaded CMC–RPH nanoparticles (Lut-R-C) were evaluated. The results of in vitro release showed that compared with Lut-R, Lut-R-C could effectively slow down the release of lutein in the stomach (19.55 ± 1.71% and 8.10 ± 0.41%) and accelerate its release after entering the small intestine (76.64 ± 1.47% and 96.07 ± 0.71%). In addition, RPH–CMC nanoparticles had good biocompatibility, and Lut-R-C nanoparticles could effectively inhibit the proliferation of breast cancer cells (MCF-7) with inhibition rate of 70% in a dose-dependent manner when lutein concentration was 20 μM. It was found that lutein uptake rate and amount in Lut-R-C treated cells were always higher than that in Lut-R treated cells. The absorption of Lut-R-C by Caco-2 cells was 90.8 times higher than that of Lut-R cells at 3 h. This study provides a new idea for improving the application of lutein in foods.