{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T06:06:57Z","timestamp":1784095617375,"version":"3.55.0"},"reference-count":60,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T00:00:00Z","timestamp":1783641600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>This study investigated the antiviral potential of silver nanoparticles (AgNPs) synthesized from Senna italica and Vepris reflexa plant extracts, rich in saponins and flavonoids. The aim was to explore the synthesis of AgNPs through green chemistry, followed by assessing their inhibitory activity against SARS-CoV-2 papain-like protease (PLpro) and evaluating cytotoxicity. The synthesized AgNPs were predominantly spherical in shape, with an average particle size in the nanoscale range (12\u201355 nm), as conformed by the transmission electron microscopy (TEM) and dynamic light scattering (DLS) analyses. A dose-dependent inhibition of SARS-CoV-2 PLpro was observed, with IC50 values ranging from 0.12 to 0.48 mg\/mL for different formulations. Cytotoxicity tests on Vero-76 cells revealed a high viability (&gt;75%) at concentrations below 0.5 mg\/mL for all AgNP samples. The findings suggest that the plant-derived AgNPs exhibit significant antiviral activity and minimal cytotoxicity, supporting their potential for further development as therapeutic agents.<\/jats:p>","DOI":"10.3390\/molecules31142428","type":"journal-article","created":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T15:13:36Z","timestamp":1783696416000},"page":"2428","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Green Synthesis Characterization and Evaluation of Senna italica and Vepris reflexa Extracts and Silver Nanoparticles Against SARS-CoV-2 PLpro Enzyme"],"prefix":"10.3390","volume":"31","author":[{"given":"Rebotile M.","family":"Machika","sequence":"first","affiliation":[{"name":"Department of Pharmaceutical Sciences, School of Pharmacy, Sefako Makgatho Health Sciences University, P.O. Box 218, Pretoria 0208, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joshua O.","family":"Olowoyo","sequence":"additional","affiliation":[{"name":"Department of Health Sciences, Marieb College of Health and Human Services, Florida Gulf Coast University, 10501 FGCU Blvd, Fort Myers, FL 33965, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9960-5565","authenticated-orcid":false,"given":"Malohle D.","family":"Tswaledi","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Biotechnology, School of Science and Technology, Sefako Makgatho Health Sciences University, P.O. Box 218, Pretoria 0208, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8178-1221","authenticated-orcid":false,"given":"Kokoette","family":"Bassey","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, School of Pharmacy, Sefako Makgatho Health Sciences University, P.O. Box 218, Pretoria 0208, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Andronova, I.V., Digilina, O.B., and Andronov, K.A. (2020). The Economic Impact of COVID-19 on the Global Community. 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