{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T12:02:19Z","timestamp":1780401739803,"version":"3.54.1"},"reference-count":38,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2022,11,4]],"date-time":"2022-11-04T00:00:00Z","timestamp":1667520000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"PT national funds (FCT\/MCTES, Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia and Minist\u00e9rio da Ci\u00eancia, Tecnologia e Ensino Superior)","doi-asserted-by":"publisher","award":["UIDB\/50006\/2020|UIDP\/50006\/2020"],"award-info":[{"award-number":["UIDB\/50006\/2020|UIDP\/50006\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"PT national funds (FCT\/MCTES, Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia and Minist\u00e9rio da Ci\u00eancia, Tecnologia e Ensino Superior)","doi-asserted-by":"publisher","award":["UIDB\/00102\/2020"],"award-info":[{"award-number":["UIDB\/00102\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Overexpression of melanin contributes to darkening of plant and fruit tissues and skin hyperpigmentation, leading to melasma or age spots. Although melanin biosynthesis is complex and involves several steps, a single enzyme known as tyrosinase is key to regulating this process. The melanogenesis pathway is initiated by oxidation of the starting material l-tyrosine (or l-DOPA) to dopaquinone by tyrosinase; the resulting quinone then serves as a substrate for subsequent steps that eventually lead to production of melanin. Medicinal plants are considered a good source of tyrosinase inhibitors. This study investigated the tyrosinase inhibitory activity of A. mollis leaf extracts and their phytochemicals. Significant activity was verified in the ethanol extract \u2013EEt (IC50 = 1.21 \u00b5g\/mL). Additionally, a kinetic study showed that this tyrosinase inhibition occurs by DIBOA (2,4-dihydroxy-1,4-benzoxazin-3-one) and verbascoside contribution through a non-competitive reaction mechanism. A synergistic effect on tyrosinase inhibition was observed in the binary combination of the compounds. In conclusion, both EEt and a mixture of two of its phytochemicals can be effective tyrosinase inhibitors and can be used as a bleaching agent for cosmetic formulations in the future.<\/jats:p>","DOI":"10.3390\/ijms232113536","type":"journal-article","created":{"date-parts":[[2022,11,8]],"date-time":"2022-11-08T11:56:36Z","timestamp":1667908596000},"page":"13536","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Synergistic Effect of DIBOA and Verbascoside from Acanthus mollis Leaf on Tyrosinase Inhibition"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2047-648X","authenticated-orcid":false,"given":"Patr\u00edcia","family":"Matos","sequence":"first","affiliation":[{"name":"Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal"},{"name":"LAQV, REQUIMTE, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal"},{"name":"CIEPQPF, FCTUC, Department of Chemical Engineering, University of Coimbra, 3000-213 Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ant\u00f3nio","family":"Paranhos","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal"},{"name":"Center for Pharmaceutical Studies, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4183-6202","authenticated-orcid":false,"given":"Maria Teresa","family":"Batista","sequence":"additional","affiliation":[{"name":"CIEPQPF, FCTUC, Department of Chemical Engineering, University of Coimbra, 3000-213 Coimbra, Portugal"},{"name":"Center for Pharmaceutical Studies, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3064-5718","authenticated-orcid":false,"given":"Artur","family":"Figueirinha","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal"},{"name":"LAQV, REQUIMTE, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"D\u2019Mello, S., Finlay, G., Baguley, B., and Askarian-Amiri, M. 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