Adsorption of black peanut skin anthocyanins, a natural pigment, onto various macroporous resins was optimized to develop a potential approach for large-scale production of black peanut skin anthocyanins. Seven different macroporous resins (AB-8, SP-207, LS-305A, HP-20, LS-305, DM-21 and LS-610B) were evaluated for the adsorption properties of the anthocyanins extracted from the black peanut skins of Arachis hypogaea L. The adsorption experiment proved that compared to AB-8, SP-207 and LS-305A, four resins, i.e., LS-610B, DM-21, LS-305 and HP-20 have relatively higher capacity of adsorbing black peanut skin anthocyanins from the aqueous solution, which are verified by the related adsorption experiments. The adsorption isotherm data was successfully described by Langmuir isotherm model and the pseudo-second-order rate model simulates the kinetic process well. Column adsorption and desorption tests further proved DM-21 is a promising adsorbent for field applications to recover black peanut skin anthocyanins from aqueous solution. The overall yield of pigment product was 14% based on dried black peanut skin, and anthocyanins purity is at about 5.7% in the pigment product.

The hard‐shelled mussel (Mytilus coruscus) has been used as a traditional Chinese medicine and health food in China for centuries. Polysaccharides from mussel has been reported to have multiple biological functions, however, it remains unclear whether mussel polysaccharide (MP) exerts protective effects in intestinal functions, and the underlying mechanisms of action remain unclear. The aim of this study was to investigate the protective effects and mechanism of MP on intestinal oxidative injury in mice. In this study, 40 male BALB/C mice were used, with 30 utilized to produce an animal model of intestinal oxidative injury with intraperitoneal injection of cyclophosphamide (Cy) for four consecutive days. The protective effects of two different doses of MP (300 and 600 mg/kg) were assessed by investigating the change in body weight, visceral index, and observing colon histomorphology. Moreover, the underlying molecular mechanisms were investigated by measuring the antioxidant enzymes and related signaling molecules through ELISA, real‐time PCR, and western blot methods. The results showed that MP pretreatment effectively protected the intestinal from Cy‐induced injury: improved the colon tissue morphology and villus structure, increased superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH‐Px) activities, and reduced malondialdehyde (MDA) content in serum and colon tissues. Meanwhile, MP also significantly increased the expression levels of SOD, GSH‐Px, heme oxygenase‐1 (HO‐1), and nuclear factor E2‐related factor 2 (Nrf2) mRNA in colon tissues. Further, western blot results showed that the expression of Nrf2 protein was significantly upregulated while kelch‐like ECH‐associated protein 1 (Keap1) was significantly downregulated by MP in the colonic tissues. This study indicates that MP can ameliorate Cy‐induced oxidative stress injury in mice, and Nrf2‐Keap1 signaling pathway may mediate these protective effects.

7,8‐dihydroxyflavone (7,8‐DHF) is a biologically active flavone with various physiological activities, including neuroprotection, anti‐inflammation, and weight loss. Previous studies have found that the efflux protein P‐glycoprotein (P‐gp) significantly affects the transepithelial transport of 7,8‐DHF in the intestine, resulting in its low oral bioavailability. Based on this, in this study, a Caco‐2 monolayer cell model was used to investigate 14 dietary plant flavonoids as potential P‐gp inhibitors, and their effects on the transepithelial transport and in vitro digestion of 7,8‐DHF were explored. The results showed that among the 14 plant flavonoids, hesperetin, epigallocatechin gallate, fisetin, kaempferol, quercetin, and isoorientin increased and the apparent permeability coefficients (P_app) of 7,8‐DHF at AP → BL direction and lowered P_app value at BL → AP direction to varying degrees, reducing the efflux ratio of 7,8‐DHF less than 1.5. In particular, kaempferol and quercetin exhibited the best effect on promoting the transepithelial transport of 7,8‐DHF, especially when used at molar concentration ratios of 1:1 and 1:2 with 7,8‐DHF. This is beneficial for improving the oral bioavailability of 7,8‐DHF. Meanwhile, 7,8‐DHF was found to maintain structural stability in simulated saliva, gastric juice, and intestinal juice, and its stability was not affected by the coexistence of quercetin and kaempferol. Overall, this study provided a theoretical basis for seeking natural and safe P‐gp inhibitors to improve the oral absorption of natural products.