Exploring the novel antioxidant peptides in low-salt dry-cured ham: Preparation, purification, identification and molecular docking.

Dry-cured ham is important source of bioactive peptides. In this study, the antioxidant activities of peptides and components from low and fully salted dry-cured hams were compared by peptidomics. And novel antioxidant peptides were identified and characterized. The results showed that the peptides (<3 KDa) extracted from low-salt dry-cured ham had higher antioxidant activity. Therefore, the antioxidant peptides in low-salt dry-cured ham were further characterized and the mechanism of their antioxidant activity was investigated. From the five candidate peptides selected, we found DWPDARGIWHND (DD12) to be highly stable, non-sensitizing, and non-toxic with the highest free radical scavenging activity. Molecular docking predicted that DD12 interacted with Keap1 through hydrogen-bond formation and hydrophobic interactions, suggesting that DD12 had good cellular antioxidant activity. DD12 peptide can bind to DPPH• and ABTS•+, resulting in strong free radical scavenging activity. Our findings support the development and application of natural antioxidant peptides in dry-cured ham.

Protective effect of onion peel extract on ageing mouse oocytes.

Mammalian oocytes not fertilized immediately after ovulation can undergo ageing and a rapid decline in quality. The addition of antioxidants can be an efficient approach to delaying the oocyte ageing process. Onion peel extract (OPE) contains quercetin and other flavonoids with natural antioxidant activities. In this study, we investigated the effect of OPE on mouse oocyte ageing and its mechanism of action. The oocytes were aged in vitro in M16 medium for 16 h after adding OPE at different concentrations (0, 50, 100, 200, and 500 µg/ml). The addition of 100 µg/ml OPE reduced the oocyte fragmentation rate, decreased the reactive oxygen species (ROS) level, increased the glutathione (GSH) level, and improved the mitochondrial membrane potential compared with the control group. The addition of OPE also increased the expression of SOD1, CAT, and GPX3 genes, and the caspase-3 activity in OPE-treated aged oocytes was significantly lower than that in untreated aged oocytes and similar to that in fresh oocytes. These results indicated that OPE delayed mouse oocyte ageing by reducing oxidative stress and apoptosis and enhancing mitochondrial function.

IN VIVO ANTI-INFLAMMATORY EFFECTS OF TARAXASTEROL AGAINST ANIMAL MODELS.

BACKGROUND: Traditional Chinese medicine Taraxacum officinale has been widely used to treat various inflammatory diseases. Taraxasterol is one of the main active components isolated from Taraxacum officinale. Recently, we have demonstrated that taraxasterol has the in vitro anti-inflammatory effects. This study aims to determine the in vivo anti-inflammatory effects of taraxasterol against animal models. MATERIALS AND METHODS: Anti-inflammatory effects were assessed in four animal models by using dimethylbenzene-induced mouse ear edema, carrageenan-induced rat paw edema, acetic acid-induced mouse vascular permeability and cotton pellet-induced rat granuloma tests. RESULTS: Our results demonstrated that taraxasterol dose-dependently attenuated dimethylbenzene-induced mouse ear edema and carrageenan-induced rat paw edema, decreased acetic acid-induced mouse vascular permeability and inhibited cotton pellet-induced rat granuloma formation. CONCLUSION: Our finding indicates that taraxasterol has obvious in vivo anti-inflammatory effects against animal models. It will provide experimental evidences for the traditional use of Taraxacum officinale and taraxasterol in inflammatory diseases.