Kimchi, a traditional fermented food regularly consumed in Korea, contains various types of antimicrobial compounds. Among the tested compounds present in common spices used in Kimchi, quercetin showed the highest selectivity index against influenza A virus (IAV) H1N1. In this study, the effect of pretreatment and periodic treatment with quercetin against IAV in Madin-Darby canine kidney cells was observed. Compared to pretreatment, periodic treatment resulted in significantly higher cell viability but lower relative expression of the IAV PA gene and total apoptosis and cell death. To explain the mechanisms underlying the antiviral effects of quercetin treatment, a comparative proteomic analysis was performed in four samples (mock, quercetin-treated, IAV-infected, and quercetin-treated IAV-infected). Among the 220 proteins, 56 proteins were classified nonhierarchically into three clusters and were differentially modulated by quercetin treatment in IAV-infected cells. Post-translational modifications were identified in 68 proteins. In conclusion, periodic treatment with quercetin is effective in reducing IAV infection, and differentially regulates the expression of key proteins, including heat shock proteins, fibronectin 1, and prohibitin to reduce IAV replication.

Abstract. Alginate oligosaccharides (AOS) have been known as a natural material with a wide variety of biological activities, and used for a long time. The evidence of using AOS to confer health benefits have been documented. The isolation and characterization of the properties, biological activity as well as the applications of AOS in various fields have been studied recently. In present work, we provide the recent research of AOS, particularly focusing on the applications in food and medicinal industry. This review also describes some experimental models, application and discuss the functional and biological mechanisms of AOS. In conclusion, AOS promotes beneficial effects on the immuno-metabolic response to various infectious diseases as well as it is promising as a biomaterial for functional foods and medicinal drugs development.