Quarternized chitosan/quercetin/polyacrylamide semi-interpenetrating network hydrogel with recoverability, toughness and antibacterial properties for wound healing

Antibiotic abuse has posed enormous burdens on patients and healthcare systems. Hence, the design and development of non-antibiotic wound dressings to meet clinical demand are urgently desired. However, there remains one of the impediments to hydrogel wound dressings that integrated with good recoverability, toughness, and excellent antibacterial properties. Herein, a series of semi-interpenetrating network (semi-IPN) hydrogels with exceptional mechanical performance and remarkable antibacterial activity based on quaternized chitosan (QCS) and polyacrylamide (PAM) were developed using a one-pot method. Additionally, the antibacterial activity of semi-IPN hydrogel against S. aureus and E. coli was enhanced by integrating it with quercetin (QT). The semi-IPN hydrogels also exhibited high recoverability and toughness, outstanding liquid absorbability (the swelling ratio reached 565 ± 12 %), and a satisfying water vapor transmission rate. Moreover, the semi-IPN hydrogels presented ideal hemocompatibility and cytocompatibility. These high-elastic hydrogels are promising candidates for potential applications in wound dressing, tissue repair, chronic wound care, as well as other biomedical fields.

Antioxidant and Antimicrobial Effects of Catechin Liposomes on Chinese Dried Pork

In this study, catechin (CT), catechin liposome (CTL), and α-tocopherol (TP) were added to Chinese dried pork to achieve a healthy lipid composition. Their effectiveness in prevention of lipid oxidation was determined by measuring the values of thiobarbituric acid-reactive substances and peroxides. The total viable count in samples was used to identify the antimicrobial activities of CT, CTL, and TP, and the pH values of the samples were determined. Chinese dried pork with antioxidants added at 600 mg/kg was subjected to sensory evaluation. Thiobarbituric acid-reactive substance values, peroxide values, and total viable counts indicated that CTL significantly enhanced the antioxidant and antibacterial effects of CT on Chinese dried pork, especially after storage at room temperature for 25 days. Compared with the two other antioxidants, CTL could better maintain the pH stability of Chinese dried pork at room temperature. Sensory evaluation revealed that the scores of CTL were better than those of CT and TP in terms of preserving the color, flavor, tenderness, and overall acceptability of Chinese dried pork. Use of CTL in Chinese dried pork had good antioxidant and antibacterial effects and maintained color, flavor, and tenderness at a relatively stable level, suggesting that CTL could be used as an antioxidant in Chinese dried pork to enhance oxidative stability and prolong shelf life.