Characterization and biological activity of PVA hydrogel containing chitooligosaccharides conjugated with gallic acid.

Propionibacterium acnes plays a key role in the onset of inflammation leading to acne and in downregulation of the defense system against oxidative stress. Therefore, antibiotics such as macrolides, tetracyclines, azelaic acid, and erythromycin are used to reduce microbial proliferation and resulting inflammation. Nonetheless, antibiotic treatment has side effects including cytotoxicity, allergy, and diarrhea. Therefore, recent studies were focused on the development of alternative antimicrobial materials. We conjugated chitooligosaccharide (COS) with gallic acid (GA) by the hydrogen peroxide-mediated method and evaluated antioxidant and antimicrobial activities. Then, we fabricated a polyvinyl alcohol (PVA) hydrogel containing COS conjugated with GA (GA-COS) for acne treatment. GA-COS at 5-10 kDa showed an excellent antioxidant activity and a better antimicrobial activity against P. acnes as compared with COS. In addition, the PVA hydrogel with GA-COS inhibited intracellular formation of reactive oxygen species and exerted antimicrobial action better than controls did.

Fabrication and characterization of phlorotannins/poly (vinyl alcohol) hydrogel for wound healing application.

Phlorotannins (PH) derived from brown algae have been shown to have biological effects. However, the application of PH in biomedical materials has not been investigated. Here, we investigated the effects of PH on normal human dermal fibroblast (NHDF) proliferation and fabricated a composite hydrogel consisting PH and poly (vinyl alcohol) (PVA) (PVA/PH) by a freezing-thawing method for wound healing applications. Cell proliferation was significantly higher in the PH-treated (0.01 and 0.02%) cells than in non-treated cells. Based on the mechanical properties, the PVA/PH hydrogel had a significantly increased swelling ratio and ultimate strain compared to the PVA hydrogel, but the ultimate tensile strength and tensile modulus were decreased. Additionally, cell attachment and proliferation on the composites were evaluated using NHDFs. The results showed that after 1 and 5 days, cell attachment and proliferation were significantly increased on the PVA/PH hydrogel compared with that on the PVA hydrogel. The findings from this study suggest that the PVA/PH hydrogel may be a candidate biomedical material for wound healing applications.

Introducing Food Fraud including translation and interpretation to Russian, Korean, and Chinese languages.

This paper introduces the topic of Food Fraud with translations to Russian, Korean, and Chinese. The concepts provide a system-wide focus leading to prevention. The goal is not to detect Food Fraud but to adjust entire food supply chains to reduce fraud opportunities. Food Fraud is a recently defined area of Food Protection between Food Safety (such as Salmonella or pesticide residue), and Food Defense (malicious intent to harm such as terrorism). Food Fraud is intentional with no intent to harm but only for economic gain. As with improving Food Safety and Food Defense, preventing Food Fraud is good for society and the economy. Society benefits through fewer public health threats from unauthorized acts. Society also benefits from increased consumer satisfaction and harmony. Food Security is increased through the production of more, higher-value products for consumers, commerce, and exporting. Food Fraud can reduce economic output because sickened citizens cannot work and it also reduces consumer confidence leading to less commerce.