Iota-Carrageenan Inhibits Replication of SARS-CoV-2 and the Respective Variants of Concern Alpha, Beta, Gamma and Delta
Maria Fröba, Maximilian Große, Christian Setz, Pia Rauch, Janina Auth, Lucas Spanaus, Jan Münch, Natalia Ruetalo, Michael Schindler, Martina Morokutti-Kurz, Philipp Graf, Eva Prieschl-Grassauer, Andreas Grassauer, Ulrich Schubert
International Journal of Molecular Sciences, doi:10.3390/ijms222413202
The COVID-19 pandemic continues to spread around the world and remains a major public health threat. Vaccine inefficiency, vaccination breakthroughs and lack of supply, especially in developing countries, as well as the fact that a non-negligible part of the population either refuse vaccination or cannot be vaccinated due to age, pre-existing illness or non-response to existing vaccines intensify this issue. This might also contribute to the emergence of new variants, being more efficiently transmitted, more virulent and more capable of escaping naturally acquired and vaccine-induced immunity. Hence, the need of effective and viable prevention options to reduce viral transmission is of outmost importance. In this study, we investigated the antiviral effect of iota-, lambda-and kappa-carrageenan, sulfated polysaccharides extracted from red seaweed, on SARS-CoV-2 Wuhan type and the spreading variants of concern (VOCs) Alpha, Beta, Gamma and Delta. Carrageenans as part of broadly used nasal and mouth sprays as well as lozenges have the potential of first line defense to inhibit the infection and transmission of SARS-CoV-2. Here, we demonstrate by using a SARS-CoV-2 spike pseudotyped lentivirus particles (SSPL) system and patient-isolated SARS-CoV-2 VOCs to infect transgenic A549ACE2/TMPRSS2 and Calu-3 human lung cells that all three carrageenan types exert antiviral activity. Iota-carrageenan exhibits antiviral activity with comparable IC 50 values against the SARS-CoV-2 Wuhan type and the VOCs. Altogether, these results indicate that iota-carrageenan might be effective for prophylaxis and treatment of SARS-CoV-2 infections independent of the present and potentially future variants.
Supplementary Materials: The following are available online at https://www.mdpi.com/article/ 10.3390/ijms222413202/s1. Author Contributions: Conceptualization, M.F., M.G., C.S., A.G. and U.S.; methodology, M.F., M.G., C.S., P.R., J.A., L.S., J.M., N.R., M.S., M.M.-K., P.G., E.P.-G. and U.S.; validation, M.F., M.G., C.S., M.S., M.M.-K., E.P.-G., A.G. and U.S.; investigation, M.F., M.G., C.S., M.S., P.R., J.A., L.S., J.M., N.R. and M.M.-K., P.G.; data curation, U.S.; writing-original draft preparation, M.F., M.G., C.S, J.M., M.M.-K. and U.S.; writing-review and editing, M.F., M.G., C.S., P.R., J.A., L.S., J.M., N.R., M.S., M.
Conflicts of Interest: The authors have read the journal's policy and declare that the authors Andreas Grassauer, Eva Prieschl-Grassauer, Philipp Graf, and Martina Morokutti-Kurz are employed by Marinomed Biotech AG. Andreas Grassauer and Eva Prieschl-Grassauer are co-founders of Marinomed Biotech AG. Andreas Grassauer, Eva Prieschl-Grassauer and Martina Morokutti-Kurz are inventors of a patent submission related to the content of the manuscript; the number of this patent application is EP20186334. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.
References
Aguiar, Tremblay, Mansfield, Woody, Lobb et al., Gene expression and in situ protein profiling of candidate SARS-CoV-2 receptors in human airway epithelial cells and lung tissue, Eur. Respir. J,
doi:10.1183/13993003.01123-2020Alsaidi, Cornejal, Mahoney, Melo, Verma et al., Griffithsin and carrageenan combination results in antiviral synergy against SARS-CoV-1 and 2 in a pseudoviral model, Mar. Drugs,
doi:10.3390/md19080418Andrei, Snoeck, Goubau, Desmyter, De Clercq, Comparative activity of various compounds against clinical strains of herpes simplex virus, Eur. J. Clin. Microbiol. Infect. Dis,
doi:10.1007/BF01967066Aune, Plant foods, antioxidant biomarkers, and the risk of cardiovascular disease, cancer, and mortality: A review of the evidence, Adv. Nutr,
doi:10.1093/advances/nmz042Auth, Fröba, Große, Rauch, Ruetalo et al., Lectin from Triticum vulgaris (WGA) inhibits infection with SARS-CoV-2 and its variants of concern alpha and beta, Int. J. Mol. Sci,
doi:10.3390/ijms221910205Becker, Dulovic, Junker, Ruetalo, Kaiser et al., Immune response to SARS-CoV-2 variants of concern in vaccinated individuals, Nat. Commun,
doi:10.1038/s41467-021-23473-6Bhattacharyya, Liu, Zhang, Jam, Dudeja et al., Carrageenan-induced innate immune response is modified by enzymes that hydrolyze distinct galactosidic bonds, J. Nutr. Biochem
Campo, Kawano, Silva, Carvalho, Carrageenans: Biological properties, chemical modifications and structural analysis-A review, Carbohydr. Polym,
doi:10.1016/j.carbpol.2009.01.020Chahla, Medina Ruiz, Ortega, Morales, Barreiro et al., A Randomized trial-Intensive treatment based in ivermectin and iota-carrageenan as pre-exposure prophylaxis for COVID-19 in healthcare agents, medRxiv
Cherian, Potdar, Jadhav, Yadav, Gupta et al., Convergent evolution of SARS-CoV-2 spike mutations, L452R, E484Q and P681R
Collier, De Marco, Ferreira, Meng, Datir et al., Sensitivity of SARS-CoV-2 B.1.1.7 to mRNA vaccine-elicited antibodies, Nature,
doi:10.1038/s41586-021-03412-7Corman, Landt, Kaiser, Molenkamp, Meijer et al., Detection of 2019 novel coronavirus (2019-nCoV) by real-time RT-PCR, Euro Surveill. Bull. Eur. Sur Les Mal. Transm. Eur. Commun. Dis. Bull,
doi:10.2807/1560-7917.ES.2020.25.3.2000045Davies, Abbott, Barnard, Jarvis, Kucharski et al., Estimated transmissibility and impact of SARS-CoV-2 lineage B.1.1.7 in England, Science
Eccles, Meier, Jawad, Weinmullner, Grassauer et al., Efficacy and safety of an antiviral Iota-Carrageenan nasal spray: A randomized, double-blind, placebo-controlled exploratory study in volunteers with early symptoms of the common cold, Respir. Res,
doi:10.1186/1465-9921-11-108Eccles, Winther, Johnston, Robinson, Trampisch et al., Efficacy and safety of iota-carrageenan nasal spray versus placebo in early treatment of the common cold in adults: The ICICC trial, Respir. Res,
doi:10.1186/s12931-015-0281-8Fazekas, Eickhoff, Pruckner, Vollnhofer, Fischmeister et al., Lessons learned from a double-blind randomised placebo-controlled study with a iota-carrageenan nasal spray as medical device in children with acute symptoms of common cold, BMC Complement. Altern. Med,
doi:10.1186/1472-6882-12-147Figueroa, Lombardo, Dogliotti, Flynn, Giugliano et al., Efficacy of a nasal spray containing iota-carrageenan in the postexposure prophylaxis of COVID-19 in hospital personnel dedicated to patients care with COVID-19 disease, Int. J. Gen. Med,
doi:10.2147/IJGM.S328486Frediansyah, The antiviral activity of iota-, kappa-, and lambda-carrageenan against COVID-19: A critical review, Clin. Epidemiol. Glob. Health,
doi:10.1016/j.cegh.2021.100826Galloway, Paul, Maccannell, Johansson, Brooks et al., Emergence of SARS-CoV-2 B.1.1.7 lineage-United States, 29, MMWR Morb. Mortal. Wkly. Rep,
doi:10.15585/mmwr.mm7003e2Gesellschaft ; Hygiene, Anwendung von Gurgel-Lösungen und Nasensprays-zwei weitere Verbündete in der Abwehr von Viralen Erkältungskrankheitenauch in Covid-19 Zeiten
Girond, Crance, Van Cuyck-Gandre, Renaudet, Deloince, Antiviral activity of carrageenan on hepatitis A virus replication in cell culture, Res. Virol,
doi:10.1016/0923-2516(91)90011-QGraf, Bernkop-Schnürch, Egyed, Koller, Prieschl-Grassauer et al., Development of a nasal spray containing xylometazoline hydrochloride and iota-carrageenan for the symptomatic relief of nasal congestion caused by rhinitis and sinusitis, Int. J. Gen. Med,
doi:10.2147/IJGM.S167123Grassauer, Weinmuellner, Meier, Pretsch, Prieschl-Grassauer et al., Iota-carrageenan is a potent inhibitor of rhinovirus infection, Virol. J,
doi:10.1186/1743-422X-5-107Große, Ruetalo, Layer, Hu, Businger et al., Quinine inhibits infection of human cell lines with SARS-CoV-2, Viruses,
doi:10.3390/v13040647Hebar, Koller, Seifert, Chabicovsky, Bodenteich et al., Non-clinical safety evaluation of intranasal iota-carrageenan, PLoS ONE,
doi:10.1371/journal.pone.0122911Hemilä, Chalker, Carrageenan nasal spray may double the rate of recovery from coronavirus and influenza virus infections: Re-analysis of randomized trial data, Pharmacol. Res. Perspect,
doi:10.1002/prp2.810Hoffmann, Kleine-Weber, Schroeder, Krüger, Herrler et al., SARS-CoV-2 cell entry depends on ACE2 and TMPRSS2 and is blocked by a clinically proven protease inhibitor, Cell,
doi:10.1016/j.cell.2020.02.052Hou, Okuda, Edwards, Martinez, Asakura et al., SARS-CoV-2 reverse genetics reveals a variable infection gradient in the respiratory tract, Cell,
doi:10.1016/j.cell.2020.05.042Jang, Shin, Lee, Kwon, Shin et al., Antiviral activity of lambdacarrageenan against influenza viruses and severe acute respiratory syndrome coronavirus 2, Sci. Rep,
doi:10.1038/s41598-020-80896-9Kemp, Meng, Ferriera, Datir, Harvey et al., Recurrent emergence and transmission of a SARS-CoV-2 spike deletion H69/V70, bioRxiv
Kim, Jang, Soh, Lee, Lee, The Impact on infectivity and neutralization efficiency of SARS-CoV-2 lineage B.1.351 pseudovirus, Viruses,
doi:10.3390/v13040633Koenighofer, Lion, Bodenteich, Prieschl-Grassauer, Grassauer et al., Carrageenan nasal spray in virus confirmed common cold: Individual patient data analysis of two randomized controlled trials, Multidiscip. Respir. Med,
doi:10.1186/2049-6958-9-57Korber, Fischer, Gnanakaran, Yoon, Theiler et al., Tracking changes in SARS-CoV-2 spike: Evidence that D614G increases infectivity of the COVID-19 virus, Cell,
doi:10.1016/j.cell.2020.06.043Leibbrandt, Meier, König-Schuster, Weinmüllner, Kalthoff et al., Iota-carrageenan is a potent inhibitor of influenza A virus infection, PLoS ONE,
doi:10.1371/journal.pone.0014320Levendosky, Mizenina, Martinelli, Jean-Pierre, Kizima et al., griffithsin and carrageenan combination to target herpes simplex virus 2 and human papillomavirus, Antimicrob. Agents Chemother,
doi:10.1128/AAC.01816-15Little, Read, Amlôt, Chadborn, Rice et al., Reducing risks from coronavirus transmission in the home-the role of viral load, BMJ,
doi:10.1136/bmj.m1728Liu, Zhan, Wan, Wang, Wang, Review for carrageenan-based pharmaceutical biomaterials: Favourable physical features versus adverse biological effects, Carbohydr. Polym,
doi:10.1016/j.carbpol.2014.11.063Ludwig, Enzenhofer, Schneider, Rauch, Bodenteich et al., Efficacy of a Carrageenan nasal spray in patients with common cold: A randomized controlled trial, Respir. Res,
doi:10.1186/1465-9921-14-124Luo, Shao, Nie, Wei, Li et al., Antitumor and adjuvant activity of λ-carrageenan by stimulating immune response in cancer immunotherapy, Sci. Rep,
doi:10.1038/srep11062Mani, Johnson, Steel, Broszczak, Neilsen et al., Natural product-derived phytochemicals as potential agents against coronaviruses: A review, Virus Res,
doi:10.1016/j.virusres.2020.197989Mitsuya, Looney, Kuno, Ueno, Wong-Staal et al., Dextran sulfate suppression of viruses in the HIV family: Inhibition of virion binding to CD4+ cells, Science,
doi:10.1126/science.2452480Morokutti-Kurz, Fröba, Graf, Große, Grassauer et al., Iota-carrageenan neutralizes SARS-CoV-2 and inhibits viral replication in vitro, PLoS ONE
Morokutti-Kurz, Graf, Prieschl-Grassauer, Amylmetacresol/2,4-dichlorobenzyl alcohol, hexylresorcinol, or carrageenan lozenges as active treatments for sore throat, Int. J. Gen. Med,
doi:10.2147/IJGM.S120665Morokutti-Kurz, König-Schuster, Koller, Graf, Graf et al., The intranasal application of zanamivir and carrageenan is synergistically active against influenza a virus in the murine model, PLoS ONE,
doi:10.1371/journal.pone.0128794Morokutti-Kurz, Unger-Manhart, Graf, Rauch, Kondar et al., The saliva of probands sucking an iota-carrageenan containing lozenge inhibits viral binding and replication of the most predominant common cold viruses and SARS-CoV-2, Int. J. Gen. Med,
doi:10.2147/IJGM.S325861Moulard, Lortat-Jacob, Mondor, Roca, Wyatt et al., Selective interactions of polyanions with basic surfaces on human immunodeficiency virus type 1 gp120, J. Virol,
doi:10.1128/JVI.74.4.1948-1960.2000Mwenda, Saasa, Sinyange, Busby, Chipimo et al., Detection of B.1.351 SARS-CoV-2 variant strain-Zambia, december 2020, MMWR Morb. Mortal. Wkly. Rep
Nyberg, Ekblad, Bergström, Freeman, Parish et al., The low molecular weight heparan sulfate-mimetic, PI-88, inhibits cell-to-cell spread of herpes simplex virus, Antivir. Res,
doi:10.1016/j.antiviral.2004.01.001Ou, Liu, Lei, Li, Mi et al., Characterization of spike glycoprotein of SARS-CoV-2 on virus entry and its immune cross-reactivity with SARS-CoV, Nat. Commun,
doi:10.1038/s41467-020-15562-9Planas, Veyer, Baidaliuk, Staropoli, Guivel-Benhassine et al., Reduced sensitivity of SARS-CoV-2 variant delta to antibody neutralization, Nature,
doi:10.1038/s41586-021-03777-9Sanda, Morrison, Goldman, N-and O-glycosylation of the SARS-CoV-2 spike protein, Anal. Chem
Schütz, Conzelmann, Fois, Groß, Weil et al., Carrageenan-containing over-the-counter nasal and oral sprays inhibit SARS-CoV-2 infection of airway epithelial cultures, Am. J. Physiol. Lung Cell. Mol. Physiol,
doi:10.1152/ajplung.00552.2020Seyedpour, Khodaei, Loghman, Seyedpour, Kisomi et al., Targeted therapy strategies against SARS-CoV-2 cell entry mechanisms: A systematic review of in vitro and in vivo studies, J. Cell. Physiol,
doi:10.1002/jcp.30032Shrestha, Marco Canosa, Nowacki, Procop, Vogel et al., Distribution of transmission potential during nonsevere COVID-19 illness, Clin. Infect. Dis,
doi:10.1093/cid/ciaa886Talarico, Damonte, Interference in dengue virus adsorption and uncoating by carrageenans, Virology
Tegally, Wilkinson, Giovanetti, Iranzadeh, Fonseca et al., Emergence and rapid spread of a new severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) lineage with multiple spike mutations in South Africa, medRxiv
Uemura, Sasaki, Sanaki, Toba, Takahashi et al., MRC5 cells engineered to express ACE2 serve as a model system for the discovery of antivirals targeting SARS-CoV-2, Sci. Rep,
doi:10.1038/s41598-021-84882-7Usfda, Part 172-Food Additives Permitted for Direct Addition to Food for Human Consumption
Volz, Mishra, Chand, Barrett, Johnson et al., Assessing transmissibility of SARS-CoV-2 lineage B.1.1.7 in England, Nature,
doi:10.1038/s41586-021-03470-xWan, Shang, Graham, Baric, Li, Receptor recognition by the novel coronavirus from Wuhan: An analysis based on decade-long structural studies of SARS coronavirus, J. Virol,
doi:10.1128/JVI.00127-20Wang, Casner, Nair, Wang, Yu et al., Increased resistance of SARS-CoV-2 variant P.1 to antibody neutralization, bioRxiv,
doi:10.1016/j.chom.2021.04.007Wibmer, Ayres, Hermanus, Madzivhandila, Kgagudi et al., SARS-CoV-2 501Y.V2 escapes neutralization by South African COVID-19 donor plasma, Nat. Med,
doi:10.1038/s41591-021-01285-xYermak, Barabanova, Aminin, Davydova, Sokolova et al., Effects of structural peculiarities of carrageenans on their immunomodulatory and anticoagulant activities, Carbohydr. Polym,
doi:10.1016/j.carbpol.2011.08.053Younes, Aggett, Aguilar, Crebelli, Filipič et al., Re-evaluation of carrageenan (E • 407) and processed Eucheuma seaweed (E • 407a) as food additives, EFSA J
Zhao, Zhang, Xu, Huang, Zhong et al., Description and clinical treatment of an early outbreak of severe acute respiratory syndrome (SARS) in Guangzhou, PR China, J. Med. Microbiol,
doi:10.1099/jmm.0.05320-0Zhou, Sheng, Yao, Wang, Effect of low molecular lambda-carrageenan from Chondrus ocellatus on antitumor H-22 activity of 5-Fu, Pharmacol. Res,
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'abstract': '<jats:p>The COVID-19 pandemic continues to spread around the world and remains a major public '
'health threat. Vaccine inefficiency, vaccination breakthroughs and lack of supply, especially '
'in developing countries, as well as the fact that a non-negligible part of the population '
'either refuse vaccination or cannot be vaccinated due to age, pre-existing illness or '
'non-response to existing vaccines intensify this issue. This might also contribute to the '
'emergence of new variants, being more efficiently transmitted, more virulent and more capable '
'of escaping naturally acquired and vaccine-induced immunity. Hence, the need of effective and '
'viable prevention options to reduce viral transmission is of outmost importance. In this '
'study, we investigated the antiviral effect of iota-, lambda- and kappa-carrageenan, sulfated '
'polysaccharides extracted from red seaweed, on SARS-CoV-2 Wuhan type and the spreading '
'variants of concern (VOCs) Alpha, Beta, Gamma and Delta. Carrageenans as part of broadly used '
'nasal and mouth sprays as well as lozenges have the potential of first line defense to '
'inhibit the infection and transmission of SARS-CoV-2. Here, we demonstrate by using a '
'SARS-CoV-2 spike pseudotyped lentivirus particles (SSPL) system and patient-isolated '
'SARS-CoV-2 VOCs to infect transgenic A549ACE2/TMPRSS2 and Calu-3 human lung cells that all '
'three carrageenan types exert antiviral activity. Iota-carrageenan exhibits antiviral '
'activity with comparable IC50 values against the SARS-CoV-2 Wuhan type and the VOCs. '
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'reference': [ { 'key': 'ref1',
'unstructured': 'COVID-19 Dashboard by the Center for Systems Science and Engineering '
'(CSSE) at Johns Hopkins Universityhttps://coronavirus.jhu.edu/map.html'},
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{'key': 'ref4', 'doi-asserted-by': 'publisher', 'DOI': '10.1099/jmm.0.05320-0'},
{'key': 'ref5', 'doi-asserted-by': 'publisher', 'DOI': '10.1128/JVI.00127-20'},
{'key': 'ref6', 'doi-asserted-by': 'publisher', 'DOI': '10.1021/acs.analchem.0c03173'},
{'key': 'ref7', 'doi-asserted-by': 'publisher', 'DOI': '10.1126/science.abb9983'},
{'key': 'ref8', 'doi-asserted-by': 'publisher', 'DOI': '10.1016/j.cell.2020.02.052'},
{'key': 'ref9', 'doi-asserted-by': 'publisher', 'DOI': '10.1002/jcp.30032'},
{'key': 'ref10', 'doi-asserted-by': 'publisher', 'DOI': '10.1038/s41467-020-15562-9'},
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{'key': 'ref13', 'doi-asserted-by': 'publisher', 'DOI': '10.2139/ssrn.3780277'},
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'article-title': 'Emergence and rapid spread of a new severe acute respiratory '
'syndrome-related coronavirus 2 (SARS-CoV-2) lineage with multiple spike '
'mutations in South Africa',
'author': 'Tegally',
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'journal-title': 'medRxiv'},
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'P681R, in the second wave of COVID-19 in Maharashtra, India',
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'Transmission from Newly-Infected Individuals with Documented Previous '
'Infection or '
'Vaccinationhttps://www.ecdc.europa.eu/en/publications-data/sars-cov-2-transmission-newly-infected-individuals-previous-infection#copy-to-clipboard'},
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{'key': 'ref30', 'doi-asserted-by': 'publisher', 'DOI': '10.1093/cid/ciaa886'},
{'key': 'ref31', 'doi-asserted-by': 'publisher', 'DOI': '10.3390/v13040647'},
{'key': 'ref32', 'doi-asserted-by': 'publisher', 'DOI': '10.1016/j.virusres.2020.197989'},
{'key': 'ref33', 'doi-asserted-by': 'publisher', 'DOI': '10.3390/ijms221910205'},
{'key': 'ref34', 'doi-asserted-by': 'publisher', 'DOI': '10.1016/j.carbpol.2014.11.063'},
{'key': 'ref35', 'doi-asserted-by': 'publisher', 'DOI': '10.1186/1743-422X-5-107'},
{'key': 'ref36', 'doi-asserted-by': 'publisher', 'DOI': '10.1371/journal.pone.0014320'},
{'key': 'ref37', 'doi-asserted-by': 'publisher', 'DOI': '10.2147/IJGM.S120665'},
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'author': 'Morokutti-Kurz',
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'journal-title': 'PLoS ONE'},
{'key': 'ref39', 'doi-asserted-by': 'publisher', 'DOI': '10.1152/ajplung.00552.2020'},
{'key': 'ref40', 'doi-asserted-by': 'publisher', 'DOI': '10.1038/s41598-020-80896-9'},
{'key': 'ref41', 'doi-asserted-by': 'publisher', 'DOI': '10.1186/1472-6882-12-147'},
{'key': 'ref42', 'doi-asserted-by': 'publisher', 'DOI': '10.1186/2049-6958-9-57'},
{'key': 'ref43', 'doi-asserted-by': 'publisher', 'DOI': '10.1186/1465-9921-14-124'},
{'key': 'ref44', 'doi-asserted-by': 'publisher', 'DOI': '10.1186/1465-9921-11-108'},
{'key': 'ref45', 'doi-asserted-by': 'publisher', 'DOI': '10.1186/s12931-015-0281-8'},
{'key': 'ref46', 'doi-asserted-by': 'publisher', 'DOI': '10.2147/IJGM.S328486'},
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'article-title': 'A Randomized trial—Intensive treatment based in ivermectin and '
'iota-carrageenan as pre-exposure prophylaxis for COVID-19 in healthcare '
'agents',
'author': 'Chahla',
'year': '2021',
'journal-title': 'medRxiv'},
{'key': 'ref48'}, {'key': 'ref49'}, {'key': 'ref50'},
{'key': 'ref51', 'doi-asserted-by': 'publisher', 'DOI': '10.1016/j.carbpol.2009.01.020'},
{'key': 'ref52', 'doi-asserted-by': 'publisher', 'DOI': '10.1016/j.cegh.2021.100826'},
{'key': 'ref53', 'doi-asserted-by': 'publisher', 'DOI': '10.1183/13993003.01123-2020'},
{'key': 'ref54', 'doi-asserted-by': 'publisher', 'DOI': '10.3390/md19080418'},
{'key': 'ref55', 'doi-asserted-by': 'publisher', 'DOI': '10.1056/NEJMoa2022926'},
{'key': 'ref56', 'doi-asserted-by': 'publisher', 'DOI': '10.1093/advances/nmz042'},
{'key': 'ref57', 'doi-asserted-by': 'publisher', 'DOI': '10.1371/journal.pone.0128794'},
{'key': 'ref58', 'doi-asserted-by': 'publisher', 'DOI': '10.1038/srep11062'},
{'key': 'ref59', 'doi-asserted-by': 'publisher', 'DOI': '10.1128/AAC.01816-15'},
{'key': 'ref60', 'doi-asserted-by': 'publisher', 'DOI': '10.1002/prp2.810'},
{'key': 'ref61', 'doi-asserted-by': 'publisher', 'DOI': '10.2147/IJGM.S325861'},
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'unstructured': 'Deutsche Gesellschaft für Krankenhaushygiene e.V.: Empfehlung der DGKH: '
'Viruzides Gurgeln und Viruzider '
'Nasensprayhttps://www.krankenhaushygiene.de/pdfdata/2020_12_02_Empfehlung-viruzides-gurgeln-nasenspray.pdf'},
{ 'key': 'ref63',
'unstructured': 'Österreichische Gesellschaft für Hygiene, M.u.P. Anwendung von '
'Gurgel-Lösungen und Nasensprays–zwei weitere Verbündete in der Abwehr '
'von Viralen Erkältungskrankheitenauch in Covid-19 '
'Zeitenhttps://www.oeghmp.at/media/anwendung_von_gurgel-loesungen_und_nasensprays.pdf'},
{ 'key': 'ref64',
'unstructured': 'Marinomed Biotech AG: Carragelose® Containing Products '
'Launchedhttps://www.carragelose.com/en/portfolio/launched-products'},
{'key': 'ref65', 'doi-asserted-by': 'publisher', 'DOI': '10.1016/0923-2516(91)90011-Q'},
{'key': 'ref66', 'doi-asserted-by': 'publisher', 'DOI': '10.1038/s41598-021-84882-7'},
{'key': 'ref67', 'doi-asserted-by': 'publisher', 'DOI': '10.1016/j.carbpol.2011.08.053'},
{'key': 'ref68', 'doi-asserted-by': 'publisher', 'DOI': '10.1016/j.jnutbio.2009.07.002'},
{'key': 'ref69', 'doi-asserted-by': 'publisher', 'DOI': '10.1016/j.phrs.2005.09.009'},
{'key': 'ref70', 'doi-asserted-by': 'publisher', 'DOI': '10.1016/j.canlet.2005.11.032'},
{'key': 'ref71', 'doi-asserted-by': 'publisher', 'DOI': '10.1016/j.aquaculture.2008.01.034'},
{ 'key': 'ref72',
'first-page': 'e05238',
'article-title': 'Re-evaluation of carrageenan (E°407) and processed Eucheuma seaweed '
'(E°407a) as food additives',
'volume': '16',
'author': 'Younes',
'year': '2018',
'journal-title': 'EFSA J.'},
{ 'key': 'ref73',
'series-title': 'Title 21 of the Code of Federal Regulation',
'article-title': 'Part 172—Food Additives Permitted for Direct Addition to Food for Human '
'Consumption, Sec. 172.620 Carrageenan',
'volume': 'Volume 3',
'year': '2020'},
{'key': 'ref74', 'doi-asserted-by': 'publisher', 'DOI': '10.1371/journal.pone.0122911'},
{'key': 'ref75', 'doi-asserted-by': 'publisher', 'DOI': '10.1016/j.antiviral.2004.01.001'},
{'key': 'ref76', 'doi-asserted-by': 'publisher', 'DOI': '10.1126/science.2452480'},
{'key': 'ref77', 'doi-asserted-by': 'publisher', 'DOI': '10.1007/BF01967066'},
{'key': 'ref78', 'doi-asserted-by': 'publisher', 'DOI': '10.1371/journal.ppat.0020069'},
{'key': 'ref79', 'doi-asserted-by': 'publisher', 'DOI': '10.1016/j.virol.2007.01.043'},
{'key': 'ref80', 'doi-asserted-by': 'publisher', 'DOI': '10.2174/1874357902014010009'},
{'key': 'ref81', 'doi-asserted-by': 'publisher', 'DOI': '10.1128/JVI.74.4.1948-1960.2000'},
{'key': 'ref82', 'doi-asserted-by': 'publisher', 'DOI': '10.2147/IJGM.S167123'},
{'key': 'ref83', 'doi-asserted-by': 'publisher', 'DOI': '10.1038/s41467-021-23473-6'},
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'DOI': '10.1093/oxfordjournals.aje.a118408'},
{ 'key': 'ref85',
'doi-asserted-by': 'publisher',
'DOI': '10.2807/1560-7917.ES.2020.25.3.2000045'}],
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