{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T13:36:30Z","timestamp":1785418590281,"version":"3.56.0"},"reference-count":43,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,5,27]],"date-time":"2026-05-27T00:00:00Z","timestamp":1779840000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002644","name":"Pukyong National University","doi-asserted-by":"publisher","award":["202506290001"],"award-info":[{"award-number":["202506290001"]}],"id":[{"id":"10.13039\/501100002644","id-type":"DOI","asserted-by":"publisher"}]},{"award":["202506290001"],"award-info":[{"award-number":["202506290001"]}],"id":[{"id":"https:\/\/ror.org\/0433kqc49","id-type":"ROR","asserted-by":"publisher"}]},{"name":"project titled \u2018Global bluefood leadership project","award":["RS-2025-02373103"],"award-info":[{"award-number":["RS-2025-02373103"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Marine natural products, including seaweeds, sponges, and marine microorganisms, have emerged as promising sources of bioactive compounds with diverse pharmacological properties. We investigated the antibacterial and antioxidant potential of ethanol extracts (30%, 60%, and 90%) from Saccharina japonica collected from two Korean coastal regions, Gijang and Wando, and evaluated their bioactive metabolites through integrated in vitro and in silico approaches. Among the extracts, the 60% ethanol fraction exhibited the highest total phenolic content and strongest 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity, indicating superior antioxidant capacity. Antibacterial assays revealed selective concentration-dependent inhibition against Staphylococcus aureus, while limited effects were observed against Escherichia coli. Kinetic analysis further demonstrated growth suppression of S. aureus at higher concentrations. Molecular docking was performed against multiple bacterial proteins, including DNA gyrase, topoisomerase IV, and tyrosyl-tRNA synthetase. Sterol compounds, particularly fucosterol and 24-methylene cholesterol, showed strong binding affinities across key targets, suggesting their potential role as multitarget antibacterial agents. ADMET predictions indicated favorable pharmacokinetic properties, although high lipophilicity and potential hERG II inhibition were noted. Overall, while the antibacterial effects observed were moderate, these findings suggest that marine-derived sterols from S. japonica may represent compounds of interest for further mechanistic investigation and optimization in complementary antibacterial strategies.<\/jats:p>","DOI":"10.3390\/pathogens15060576","type":"journal-article","created":{"date-parts":[[2026,5,27]],"date-time":"2026-05-27T12:31:56Z","timestamp":1779885116000},"page":"576","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Marine-Derived Sterols from Saccharina japonica: Potential Antibacterial Activity and Target Prediction Against Bacterial Pathogens Through Integrated In Vitro and In Silico Approaches"],"prefix":"10.3390","volume":"15","author":[{"given":"Eun-Seop","family":"Lee","sequence":"first","affiliation":[{"name":"Department of Aquatic Life Medicine, Pukyong National University, Busan 48513, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chae-Min","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Aquatic Life Medicine, Pukyong National University, Busan 48513, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Si-Heon","family":"Song","sequence":"additional","affiliation":[{"name":"Department of Aquatic Life Medicine, Pukyong National University, Busan 48513, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Su-Bin","family":"Jeon","sequence":"additional","affiliation":[{"name":"Department of Aquatic Life Medicine, Pukyong National University, Busan 48513, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Byeong-Su","family":"Kang","sequence":"additional","affiliation":[{"name":"Department of Aquatic Life Medicine, Pukyong National University, Busan 48513, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Md Sekendar","family":"Ali","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, International Islamic University Chittagong, Kumira, Chittagong 4318, Bangladesh"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8668-4508","authenticated-orcid":false,"given":"Eon-Bee","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Aquatic Life Medicine, Pukyong National University, Busan 48513, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"50","DOI":"10.56782\/pps.341","article-title":"Curbing Anti-Microbial Resistance of Synthetic Medicinal Agents Using Herbal Drug Alternatives: Current Trends and Future Insights","volume":"23","author":"Bushra","year":"2025","journal-title":"Prospect. Pharm. Sci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.56782\/pps.336","article-title":"Antimicrobial Efficacy and Time-Kill Kinetics of Phoenix dactylifera L. Seed Oil Against Multidrug Resistant Pathogens from Cancer Patients","volume":"23","author":"Oluyele","year":"2025","journal-title":"Prospect. Pharm. Sci."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Lomartire, S., and Gon\u00e7alves, A.M.M. (2022). An Overview of Potential Seaweed-Derived Bioactive Compounds for Pharmaceutical Applications. Mar. Drugs, 20.","DOI":"10.3390\/md20020141"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Lu, W.-J., Lin, H.-J., Hsu, P.-H., Lai, M., Chiu, J.-Y., and Lin, H.-T.V. (2019). Brown and Red Seaweeds Serve as Potential Efflux Pump Inhibitors for Drug-Resistant Escherichia coli. Evid. Based. Complement. Altern. Med., 2019.","DOI":"10.1155\/2019\/1836982"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Wan, H., Zhang, Y.-X., Gao, Z.-C., Shan, G.-Y., Liu, F., and Li, H.-J. (2025). Exploring the Potential of Fucoidan from Laminaria japonica: A Comprehensive Review of Its Biological Activities and Benefits for Human. Int. J. Biol. Macromol., 307.","DOI":"10.1016\/j.ijbiomac.2025.142297"},{"key":"ref_6","unstructured":"Liu, X. (2020). Extraction and Anti-Bacterial Effects of Edible Brown Algae Extracts, North Carolina State University."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Generali\u0107 Mekini\u0107, I., Skroza, D., \u0160imat, V., Hamed, I., \u010cagalj, M., and Popovi\u0107 Perkovi\u0107, Z. (2019). Phenolic Content of Brown Algae (Pheophyceae) Species: Extraction, Identification, and Quantification. Biomolecules, 9.","DOI":"10.3390\/biom9060244"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"12093","DOI":"10.3390\/molecules200712093","article-title":"Chemical Composition and Antioxidant and Antibacterial Activities of an Essential Oil Extracted from an Edible Seaweed, Laminaria japonica L.","volume":"20","author":"Patra","year":"2015","journal-title":"Molecules"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Cai, J., Feng, J., Xie, S., Wang, F., and Xu, Q. (2014). Laminaria japonica Extract, an Inhibitor of Clavibater michiganense subsp. Sepedonicum. PLoS ONE, 9.","DOI":"10.1371\/journal.pone.0094329"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"573","DOI":"10.3136\/fstr.14.573","article-title":"Commercial-Scale Preparation of Biofunctional Fucoxanthin from Waste Parts of Brown Sea Algae Laminalia japonica","volume":"14","author":"Kanazawa","year":"2008","journal-title":"Food Sci. Technol. Res."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"6","DOI":"10.1016\/j.ijbiomac.2009.10.015","article-title":"Potential Antioxidant and Anticoagulant Capacity of Low Molecular Weight Fucoidan Fractions Extracted from Laminaria japonica","volume":"46","author":"Wang","year":"2010","journal-title":"Int. J. Biol. Macromol."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Castej\u00f3n, N., Parailloux, M., Izdebska, A., Lobinski, R., and Fernandes, S.C.M. (2021). Valorization of the Red Algae Gelidium Sesquipedale by Extracting a Broad Spectrum of Minor Compounds Using Green Approaches. Mar. Drugs, 19.","DOI":"10.3390\/md19100574"},{"key":"ref_13","unstructured":"(2023). Performance Standards for Antimicrobial Disk and Dilution Susceptibility Tests for Bacteria Isolated from Animals (Standard No. CLSI M07). Available online: https:\/\/clsi.org\/shop\/standards\/m07\/."},{"key":"ref_14","first-page":"116","article-title":"In Silico and in Vitro Study on the Inhibition of FtsZ Protein of Staphylococcus aureus by Active Compounds from Andrographis paniculata","volume":"11","author":"Selvaraj","year":"2021","journal-title":"J. Biol. Act. Prod. Nat."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1007\/978-1-4939-2269-7_19","article-title":"Small-Molecule Library Screening by Docking with PyRx","volume":"1263","author":"Dallakyan","year":"2015","journal-title":"Methods Mol. Biol."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Teodosio, J.J.R., Dizon, K.A.H., Bruna, J.R., Sollesta, J.V.N., Villorente, Z.M., Saludes, J.P., and Dalisay, D.S. (2026). Biochanin A, a Plant Isoflavone, Disrupts Peptidoglycan Biosynthesis by Downregulating FemA and FemB, and Impairs Cell Wall Integrity in Multidrug-Resistant Staphylococcus Aureus. Antibiotics, 15.","DOI":"10.3390\/antibiotics15020195"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1385","DOI":"10.4049\/jimmunol.171.3.1385","article-title":"Functional Analysis of the TCR Binding Domain of Toxic Shock Syndrome Toxin-1 Predicts Further Diversity in MHC Class II\/Superantigen\/TCR Ternary Complexes","volume":"171","author":"McCormick","year":"2003","journal-title":"J. Immunol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1080\/07391102.2010.10507353","article-title":"Molecular Docking Studies to Map the Binding Site of Squalene Synthase Inhibitors on Dehydrosqualene Synthase of Staphylococcus Aureus","volume":"28","author":"Kahlon","year":"2010","journal-title":"J. Biomol. Struct. Dyn."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Daina, A., Michielin, O., and Zoete, V. (2017). SwissADME: A Free Web Tool to Evaluate Pharmacokinetics, Drug-Likeness and Medicinal Chemistry Friendliness of Small Molecules. Sci. Rep., 7.","DOI":"10.1038\/srep42717"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"4066","DOI":"10.1021\/acs.jmedchem.5b00104","article-title":"PkCSM: Predicting Small-Molecule Pharmacokinetic and Toxicity Properties Using Graph-Based Signatures","volume":"58","author":"Pires","year":"2015","journal-title":"J. Med. Chem."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Jang, E.J., Kim, S.C., Lee, J.-H., Lee, J.R., Kim, I.K., Baek, S.Y., and Kim, Y.W. (2018). Fucoxanthin, the Constituent of Laminaria japonica, Triggers AMPK-Mediated Cytoprotection and Autophagy in Hepatocytes under Oxidative Stress. BMC Complement. Altern. Med., 18.","DOI":"10.1186\/s12906-018-2164-2"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Karpi\u0144ski, T.M., and Adamczak, A. (2019). Fucoxanthin\u2014An Antibacterial Carotenoid. Antioxidants, 8.","DOI":"10.3390\/antiox8080239"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"152","DOI":"10.1016\/S0076-6879(99)99017-1","article-title":"[14] Analysis of Total Phenols and Other Oxidation Substrates and Antioxidants by Means of Folin-Ciocalteu Reagent","volume":"299","author":"Singleton","year":"1999","journal-title":"Methods Enzymol."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Fu, C.W.F., Ho, C.W., Yong, W.T.L., Abas, F., Tan, T.B., and Tan, C.P. (2016). Extraction of Phenolic Antioxidants from Four Selected Seaweeds Obtained from Sabah. Int. Food Res. J., 23.","DOI":"10.7287\/peerj.preprints.1249v1"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1515\/bmc-2022-0003","article-title":"Seaweeds\u2019 Pigments and Phenolic Compounds with Antimicrobial Potential","volume":"13","author":"Gomes","year":"2022","journal-title":"Biomol. Concepts"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Saxena, D., Maitra, R., Bormon, R., Czekanska, M., Meiers, J., Titz, A., Verma, S., and Chopra, S. (2023). Tackling the Outer Membrane: Facilitating Compound Entry into Gram-Negative Bacterial Pathogens. npj Antimicrob. Resist., 1.","DOI":"10.1038\/s44259-023-00016-1"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1111\/nyas.14134","article-title":"Permeability Barriers of Gram-negative Pathogens","volume":"1459","author":"Zgurskaya","year":"2019","journal-title":"Ann. N. Y. Acad. Sci."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"\u010cmikov\u00e1, N., Galovi\u010dov\u00e1, L., Mi\u0161keje, M., Borotov\u00e1, P., Kluz, M., and Ka\u010d\u00e1niov\u00e1, M. (2022). Determination of Antioxidant, Antimicrobial Activity, Heavy Metals and Elements Content of Seaweed Extracts. Plants, 11.","DOI":"10.3390\/plants11111493"},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"da Silva, F.E.F., \u00c1vila, F.d.N., Pereira, N.M.O., de Freitas, M.D., Pessoa, O.D.L., da Fonseca, A.M., da Costa, J.G.M., and Santiago, G.M.P. (2023). Semisynthesis, in Silico Study and in Vitro Antibacterial Evaluation of Fucosterol Derivatives. Steroids, 189.","DOI":"10.1016\/j.steroids.2022.109137"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Touhtouh, J., Laghmari, M., Benali, T., Aanniz, T., Akhazzane, M., Goh, K.W., Al Abdulmonem, W., Bouyahya, A., Zengin, G., and Hammani, K. (2024). Evaluation of Antioxidant, Antimicrobial, Antidiabetic, Anti-Tyrosinase, and Neuroprotective Effects of \u03b2-Ionone: In Vitro and in Silico Analysis. Results Chem., 12.","DOI":"10.1016\/j.rechem.2024.101874"},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Kubiak, J., Szyk, P., Czarczynska-Goslinska, B., and Goslinski, T. (2025). Flavonoids, Chalcones, and Their Fluorinated Derivatives\u2014Recent Advances in Synthesis and Potential Medical Applications. Molecules, 30.","DOI":"10.3390\/molecules30112395"},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Govender, N., Zulkifli, N.S., Badrul Hisham, N.F., Ab Ghani, N.S., and Mohamed-Hussein, Z.-A. (2022). Pea Eggplant (Solanum torvum Swartz) Is a Source of Plant Food Polyphenols with SARS-CoV Inhibiting Potential. PeerJ, 10.","DOI":"10.7717\/peerj.14168"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"3867","DOI":"10.1021\/jm000292e","article-title":"Prediction of Drug Absorption Using Multivariate Statistics","volume":"43","author":"Egan","year":"2000","journal-title":"J. Med. Chem."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1021\/cc9800071","article-title":"A Knowledge-Based Approach in Designing Combinatorial or Medicinal Chemistry Libraries for Drug Discovery. 1. A Qualitative and Quantitative Characterization of Known Drug Databases","volume":"1","author":"Ghose","year":"1998","journal-title":"J. Comb. Chem."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1016\/j.addr.2012.09.019","article-title":"Experimental and Computational Approaches to Estimate Solubility and Permeability in Drug Discovery and Development Settings","volume":"64","author":"Lipinski","year":"2012","journal-title":"Adv. Drug Deliv. Rev."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1841","DOI":"10.1021\/jm015507e","article-title":"Simple Selection Criteria for Drug-like Chemical Matter","volume":"44","author":"Muegge","year":"2001","journal-title":"J. Med. Chem."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"2615","DOI":"10.1021\/jm020017n","article-title":"Molecular Properties That Influence the Oral Bioavailability of Drug Candidates","volume":"45","author":"Veber","year":"2002","journal-title":"J. Med. Chem."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"6","DOI":"10.1046\/j.1365-2362.33.s2.4.x","article-title":"Importance of P-glycoprotein for Drug Disposition in Humans","volume":"33","author":"Fromm","year":"2003","journal-title":"Eur. J. Clin. Investig."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"1","DOI":"10.9734\/ijpr\/2021\/v6i230156","article-title":"Oleanolic Acid, Ursolic Acid and Apigenin from Ocimum Basilicum as Potential Inhibitors of the SARS-CoV-2 Main Protease: A Molecular Docking Study","volume":"6","author":"Matondo","year":"2021","journal-title":"Int. J. Pathog. Res."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1","DOI":"10.9734\/ijtdh\/2021\/v42i1130492","article-title":"In Silico ADME\/T Properties of Quinine Derivatives Using SwissADME and PkCSM Webservers","volume":"42","author":"Mvondo","year":"2021","journal-title":"Int. J. Trop. Dis. Health"},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Yeni, Y., and Rachmania, R.A. (2022). The Prediction of Pharmacokinetic Properties of Compounds in Hemigraphis alternata (Burm.F.) T. Ander Leaves Using PkCSM. Indones. J. Chem., 22.","DOI":"10.22146\/ijc.73117"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"382","DOI":"10.1248\/bpb.b21-00916","article-title":"Clinical Aspects of Drug\u2013Drug Interaction and Drug Nephrotoxicity at Renal Organic Cation Transporters 2 (OCT2) and Multidrug and Toxin Exclusion 1, and 2-K (MATE1\/MATE2-K)","volume":"45","author":"Saad","year":"2022","journal-title":"Biol. Pharm. Bull."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"5531","DOI":"10.1111\/bph.12996","article-title":"The Virtual Heart as a Platform for Screening Drug Cardiotoxicity","volume":"172","author":"Yuan","year":"2015","journal-title":"Br. J. Pharmacol."}],"container-title":["Pathogens"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-0817\/15\/6\/576\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,27]],"date-time":"2026-05-27T13:07:22Z","timestamp":1779887242000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-0817\/15\/6\/576"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,5,27]]},"references-count":43,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["pathogens15060576"],"URL":"https:\/\/doi.org\/10.3390\/pathogens15060576","relation":{},"ISSN":["2076-0817"],"issn-type":[{"value":"2076-0817","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,27]]}}}