{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,3]],"date-time":"2026-11-03T11:05:11Z","timestamp":1793703911202,"version":"4.5.1"},"reference-count":48,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,8,20]],"date-time":"2023-08-20T00:00:00Z","timestamp":1692489600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Education, Malaysia","award":["MO002-2019"],"award-info":[{"award-number":["MO002-2019"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Dengue has long been a serious health burden to the global community, especially for those living in the tropics. Despite the availability of vaccines, effective treatment for the infection is still needed and currently remains absent. In the present study, the antiviral properties of the Streptomyces sp. KSF 103 methanolic extract (Streptomyces KSF 103 ME), which consists of a number of potential antiviral compounds, were investigated against dengue virus serotype 2 (DENV-2). The effects of this extract against DENV-2 replication were determined using the quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Findings from the study suggested that the Streptomyces KSF 103 ME showed maximum inhibitory properties toward the virus during the virus entry stage at concentrations of more than 12.5 \u00b5g\/mL. Minimal antiviral activities were observed at other virus replication stages; adsorption (42% reduction at 50 \u00b5g\/mL), post-adsorption (67.6% reduction at 50 \u00b5g\/mL), prophylactic treatment (68.4% and 87.7% reductions at 50 \u00b5g\/mL and 25 \u00b5g\/mL, respectively), and direct virucidal assay (48% and 56.8% reductions at 50 \u00b5g\/mL and 25 \u00b5g\/mL, respectively). The Streptomyces KSF 103 ME inhibited dengue virus replication with a 50% inhibitory concentration (IC50) value of 20.3 \u00b5g\/mL and an International System of Units (SI) value of 38.9. The Streptomyces KSF 103 ME showed potent antiviral properties against dengue virus (DENV) during the entry stage. Further studies will be needed to deduce the antiviral mechanisms of the Streptomyces KSF 103 ME against DENV.<\/jats:p>","DOI":"10.3390\/v15081773","type":"journal-article","created":{"date-parts":[[2023,8,21]],"date-time":"2023-08-21T01:38:31Z","timestamp":1692581911000},"page":"1773","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Antiviral Activities of Streptomyces KSF 103 Methanolic Extracts against Dengue Virus Type-2"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3579-7171","authenticated-orcid":false,"given":"Nurfatihah","family":"Zulkifli","sequence":"first","affiliation":[{"name":"Institute of Biological Sciences, Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Wilayah Persekutuan Kuala Lumpur, Malaysia"},{"name":"Tropical Infectious Diseases Research and Education Centre (TIDREC), Universiti Malaya, Level 2, High Impact Research (HIR) Building, Kuala Lumpur 50603, Wilayah Persekutuan Kuala Lumpur, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9419-5731","authenticated-orcid":false,"given":"Jasmine-Elanie","family":"Khairat","sequence":"additional","affiliation":[{"name":"Institute of Biological Sciences, Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Wilayah Persekutuan Kuala Lumpur, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adzzie-Shazleen","family":"Azman","sequence":"additional","affiliation":[{"name":"School of Science, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 47500, Selangor, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nur-Faralyza Mohd","family":"Baharudin","sequence":"additional","affiliation":[{"name":"Institute of Biological Sciences, Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Wilayah Persekutuan Kuala Lumpur, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nurul-Adila","family":"Malek","sequence":"additional","affiliation":[{"name":"Institute of Biological Sciences, Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Wilayah Persekutuan Kuala Lumpur, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Syafiq-Asnawi","family":"Zainal Abidin","sequence":"additional","affiliation":[{"name":"Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 47500, Selangor, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9267-1420","authenticated-orcid":false,"given":"Sazaly","family":"AbuBakar","sequence":"additional","affiliation":[{"name":"Tropical Infectious Diseases Research and Education Centre (TIDREC), Universiti Malaya, Level 2, High Impact Research (HIR) Building, Kuala Lumpur 50603, Wilayah Persekutuan Kuala Lumpur, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0364-5587","authenticated-orcid":false,"given":"Pouya","family":"Hassandarvish","sequence":"additional","affiliation":[{"name":"Tropical Infectious Diseases Research and Education Centre (TIDREC), Universiti Malaya, Level 2, High Impact Research (HIR) Building, Kuala Lumpur 50603, Wilayah Persekutuan Kuala Lumpur, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Zandi, K., Teoh, B.T., Sam, S.S., Wong, P.F., Mustafa, M.R., and AbuBakar, S. 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