Preparation and characterization of active oxidized starch films containing licorice residue extracts and its potential against methicillin-resistant S. aureus.

The antibacterial and antioxidant packaging films were fabricated by incorporating licorice residue extracts (LREs) into oxidized starch (OS) films. The bioactive fraction (BF) was firstly obtained from LREs by using bioassay-guided isolation method. The BF showed potent anti-Gram(+) bacteria effects, especially against methicillin-resistant S. aureus (MRSA) with MIC of 32.5 µg/mL. The present results also indicated that the addition of BF could significantly decrease the moisture content, water vapor permeability, light transmittance of OS films. Notably, the antibacterial and antioxidant activities of OS films significantly enhanced with the concentration of BF increasing. Moreover, the films with the highest concentration of BF showed the lowest tensile strength (4.23 MPa) and the highest elongation at break (63.89%). Meanwhile, the bioactive films could release bioactive compounds such as licochalcone A and licochalcone B into the alcoholic and fatty food simulants. Taken together, the active OS films containing LREs have the potential for application in food packaging films, due to its potential against MRSA and antioxidant activity as well as good physicochemical properties.

A wheat germ-derived peptide YDWPGGRN facilitates skin wound-healing processes.

Wheat germ derivatives have been shown to inhibit inflammation-related diseases. In this study, a small peptide (YDWPGGRN) isolated from wheat germ was used to study its anti-inflammatory activity and its application in skin wound healing. Both the in vitro and in vivo results clearly showed that YDWPGGRN significantly inhibited the LPS-stimulated NO, IL-1ß, IL-6 and TNF-α production but promoted the release of an anti-inflammatory cytokine, IL-10. In addition, YDWPGGRN directly enhanced the proliferation and migration of HaCaT cells and L929 cells. Furthermore, the results demonstrated that YDWPGGRN was able to stimulate angiogenesis and collagen production in wound areas, consequently accelerating the skin wound-healing processes in a rat model with a full thickness dermal wound. The current findings suggest that YDWPGGRN promotes wound healing by anti-inflammatory reactions and enhances the proliferation and migration of keratinocytes and fibroblasts; therefore, it may be applicable for skin wound therapeutics.