{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T03:29:55Z","timestamp":1780370995748,"version":"3.54.1"},"reference-count":33,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2024,10,29]],"date-time":"2024-10-29T00:00:00Z","timestamp":1730160000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Marine Drugs"],"abstract":"<jats:p>The COVID-19 pandemic has significantly impacted our daily lives. Routine infection-control measures present an effective preventive strategy for a new infectious disease outbreak. Fucoidan, a fucose-rich sulfated polysaccharide found in brown algae, exhibits antiviral activity. Moreover, fucoidan exerts an antimicrobial effect; however, it requires considerably higher concentrations than those needed for its antiviral effect. In this study, we aimed to enhance the antimicrobial activity of fucoidan and prepared a fucoidan silver salt (Ag-Fuc) by incorporating silver ions into the sulfate groups of Yakult Fucoidan derived from Cladosiphon okamuranus Tokida. The fucoidan exhibited a weak inhibitory effect on Escherichia coli growth at significantly higher concentrations, whereas Ag-Fuc inhibited the growth of E. coli and Staphylococcus epidermidis at concentrations comparable to those required for its antiviral effects. Moreover, Ag-Fuc inhibited the growth of Cladosporium cladosporioides. Infections of human cells with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza A virus were more effectively inhibited by lower concentrations of Ag-Fuc compared with fucoidan. Overall, silver ions added to the sulfate groups induced strong antimicrobial activity and enhanced the antiviral effect of fucoidan. We suggest a wide application of Ag-Fuc as a routine preventive material to avoid new infectious disease pandemics.<\/jats:p>","DOI":"10.3390\/md22110486","type":"journal-article","created":{"date-parts":[[2024,10,29]],"date-time":"2024-10-29T08:42:09Z","timestamp":1730191329000},"page":"486","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Incorporation of Silver into Sulfate Groups Enhances Antimicrobial and Antiviral Effects of Fucoidan"],"prefix":"10.3390","volume":"22","author":[{"given":"Akira","family":"Iwata","sequence":"first","affiliation":[{"name":"Yakult Central Institute, 5-11 Izumi, Kunitachi, Tokyo 186-8650, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mayuko","family":"Yamamoto-Fujimura","sequence":"additional","affiliation":[{"name":"Yakult Central Institute, 5-11 Izumi, Kunitachi, Tokyo 186-8650, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suzuka","family":"Fujiwara","sequence":"additional","affiliation":[{"name":"Yakult Central Institute, 5-11 Izumi, Kunitachi, Tokyo 186-8650, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Saya","family":"Tajima","sequence":"additional","affiliation":[{"name":"Yakult Central Institute, 5-11 Izumi, Kunitachi, Tokyo 186-8650, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takahide","family":"Shigeyama","sequence":"additional","affiliation":[{"name":"Yakult Central Institute, 5-11 Izumi, Kunitachi, Tokyo 186-8650, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Moriya","family":"Tsukimoto","sequence":"additional","affiliation":[{"name":"Yakult Central Institute, 5-11 Izumi, Kunitachi, Tokyo 186-8650, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tatsuya","family":"Ibuki","sequence":"additional","affiliation":[{"name":"Yakult Central Institute, 5-11 Izumi, Kunitachi, Tokyo 186-8650, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Akito","family":"Kataoka-Kato","sequence":"additional","affiliation":[{"name":"Yakult Central Institute, 5-11 Izumi, Kunitachi, Tokyo 186-8650, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e397","DOI":"10.1016\/S2666-5247(23)00069-1","article-title":"Risk factors and vectors for SARS-CoV-2 household transmission: A prospective, longitudinal cohort study","volume":"4","author":"Derqui","year":"2023","journal-title":"Lancet Microbe"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Luthuli, S., Wu, S., Cheng, Y., Zheng, X., Wu, M., and Tong, H. 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