Alcohol can cause injury and lead to an inflammatory response in the liver. The NF-κB/AMPK signaling pathway plays a vital role in regulating intracellular inflammatory cytokine levels. In this study, corn oligopeptides (CPs), as the research objects, were obtained from corn gluten meal, and their regulation of the activation of the Kupffer cell NF-κB/AMPK signal pathway induced by LPS was investigated. Results showed that ALT, AST, and inflammatory cytokines in mice serum after the administration of CPs at 0.2, 0.4, and 0.8 g/kg of body weight displayed a distinct (p < 0.05) reduction. On the other hand, the CPs also inhibited the expression of recognized receptor CD14 and TLR4, down-regulated P-JNK, P-ERK, and P-p-38, and thus inhibited inflammatory cytokine levels in Kupffer cells (KCs). Furthermore, four kinds of dipeptides with a leucine residue at the C-terminus that might exhibit down-regulated inflammatory cytokines in the NF-κB/AMPK signaling pathway functions were detected using HPLC-MS/MS. These results indicated that CPs have a potential application value in acute alcoholic liver disease.

Black‐bone silky fowl (Gallus gallus domesticus Brisson) is considered to have strengthening effect on the body and immunomodulatory effects. The black‐bone silky fowl peptide (BSFP) was produced by enzymatic digestion of the whole black‐bone silky fowl (including the head and claws) after removal of the viscera. Afterwards, the four of the characteristic peptides Glu‐Phe (EF), Glu‐Glu‐Leu (EEL), Glu‐His‐Pro‐Thr (EHPT), Ala‐Gly‐Gly‐His (AGGF) of the BSFP were identified by HPLC‐MS/MS. The preventive effects of BSFP and the four characteristic peptides on antioxidant and immunomodulation were investigated. The antioxidant capacity was assessed by in vitro HepG2 intracellular reactive oxygen species (ROS). The immunomodulatory experiments were conducted by measuring the effects of the BSFP and four peptides on the proliferation of splenocytes, T and B lymphocytes cells, the CD4+/CD8+ T lymphocytes ratio, and the phagocytic capacity of macrophages and the nitric oxide (NO) content of macrophages. The four peptides of BSFP showed strong antioxidant capacity, with the most potent peptide for intracellular ROS being AGGF, with 56% inhibition. AGGF, EF, and BSFP showed highly positive effects on splenocyte proliferation and when Concanavalin A (ConA) was used as a stimulus for T lymphocytes and lipopolysaccharide (LPS) as a stimulus for B lymphocytes, the peptides stimulated cell proliferation in a dose‐dependent manner. Of these, EF, AGGF, and BSFP promoted the proliferation of T lymphocytes; EF, EHPT, and BSFP significantly promoted the proliferation of B lymphocytes. EHPT and BSFP increased the CD4+/CD8+ ratio of T cells. Needle aspiration of neutral red was significantly promoted by macrophages treated with peptides other than EF. In addition, EEL, EHPT, AGGF, and BSFP had a promotive effect on NO production in phagocytes. The results indicate that BSFP is a peptide product with good immunomodulatory functions, four peptides identified from BSFP show outstanding effects in terms of antioxidant properties and immunomodulation. Practical applications In this study, the amino acid composition and relative molecular masses of the black‐bone silky fowl peptide were analyzed, while the four peptides with significant effects on antioxidant and immunomodulatory properties in black‐bone silky fowl peptide were identified by HPLC‐MS/MS technique. Positive effects of black‐bone silky fowl peptide and its four peptides on antioxidant capacity and immunomodulatory ability as revealed by cell experiments. The results of this experiment provide a preliminary theoretical basis for the development of new functional foods using black‐bone silky fowl peptide and their characteristic peptides.