{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T13:05:13Z","timestamp":1774011913806,"version":"3.50.1"},"reference-count":96,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,6,19]],"date-time":"2023-06-19T00:00:00Z","timestamp":1687132800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Regional Development Fund (FEDER)","award":["NORTE-01-0247-FEDER-113540"],"award-info":[{"award-number":["NORTE-01-0247-FEDER-113540"]}]},{"name":"European Regional Development Fund (FEDER)","award":["PORTUGAl2020"],"award-info":[{"award-number":["PORTUGAl2020"]}]},{"name":"Competitiveness and Internationalisation Operational Programme","award":["NORTE-01-0247-FEDER-113540"],"award-info":[{"award-number":["NORTE-01-0247-FEDER-113540"]}]},{"name":"Competitiveness and Internationalisation Operational Programme","award":["PORTUGAl2020"],"award-info":[{"award-number":["PORTUGAl2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Propolis is a natural product produced by bees that contains a complex mixture of compounds, including phenolic compounds and flavonoids. These compounds contribute to its biological activities, such as antioxidant capacity. This study analysed the pollen profile, total phenolic content (TPC), antioxidant properties, and phenolic compound profile of four propolis samples from Portugal. The total phenolic compounds in the samples were determined by six different techniques: four different Folin\u2013Ciocalteu (F-C) methods, spectrophotometry (SPECT), and voltammetry (SWV). Of the six methods, SPECT allowed the highest quantification, while SWV achieved the lowest. The mean TPC values for these methods were 422 \u00b1 98 and 47 \u00b1 11 mg GAE\/g sample, respectively. Antioxidant capacity was determined by four different methods: DPPH, FRAP, original ferrocyanide (OFec), and modified ferrocyanide (MFec). The MFec method gave the highest antioxidant capacity for all samples, followed by the DPPH method. The study also investigated the correlation between TPC and antioxidant capacity with the presence of hydroxybenzoic acid (HBA), hydroxycinnamic acid (HCA), and flavonoids (FLAV) in propolis samples. The results showed that the concentrations of specific compounds in propolis samples can significantly impact their antioxidant capacity and TPC quantification. Analysis of the profile of phenolic compounds by the UHPLC-DAD-ESI-MS technique identified chrysin, caffeic acid isoprenyl ester, pinocembrin, galangin, pinobanksin-3-O-acetate, and caffeic acid phenyl ester as the major compounds in the four propolis samples. In conclusion, this study shows the importance of the choice of method for determining TPC and antioxidant activity in samples and the contribution of HBA and HCA content to their quantification.<\/jats:p>","DOI":"10.3390\/molecules28124847","type":"journal-article","created":{"date-parts":[[2023,6,19]],"date-time":"2023-06-19T03:04:40Z","timestamp":1687143880000},"page":"4847","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Comparative Methods to Evaluate the Antioxidant Capacity of Propolis: An Attempt to Explain the Differences"],"prefix":"10.3390","volume":"28","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7281-8598","authenticated-orcid":false,"given":"Vanessa B.","family":"Paula","sequence":"first","affiliation":[{"name":"Doctoral School, University of Le\u00f3n (ULE), Campus de Vegazana, 24007 Le\u00f3n, Spain"},{"name":"Centro de Investiga\u00e7\u00e3o de Montanha (CIMO), Instituto Polit\u00e9cnico de Bragan\u00e7a, 5300-252 Bragan\u00e7a, Portugal"}]},{"given":"Let\u00edcia M.","family":"Estevinho","sequence":"additional","affiliation":[{"name":"Centro de Investiga\u00e7\u00e3o de Montanha (CIMO), Instituto Polit\u00e9cnico de Bragan\u00e7a, 5300-252 Bragan\u00e7a, Portugal"},{"name":"Laborat\u00f3rio Associado para a Sustentabilidade e Tecnologia em Regi\u00f5es de Montanha (SusTEC), Instituto Polit\u00e9cnico de Bragan\u00e7a, Campus de Santa Apol\u00f3nia, 5300-253 Bragan\u00e7a, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7882-737X","authenticated-orcid":false,"given":"Susana M.","family":"Cardoso","sequence":"additional","affiliation":[{"name":"Associated Laboratory for Green Chemistry of the Network of Chemistry and Technology LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1210-4259","authenticated-orcid":false,"given":"Lu\u00eds G.","family":"Dias","sequence":"additional","affiliation":[{"name":"Centro de Investiga\u00e7\u00e3o de Montanha (CIMO), Instituto Polit\u00e9cnico de Bragan\u00e7a, 5300-252 Bragan\u00e7a, Portugal"},{"name":"Laborat\u00f3rio Associado para a Sustentabilidade e Tecnologia em Regi\u00f5es de Montanha (SusTEC), Instituto Polit\u00e9cnico de Bragan\u00e7a, Campus de Santa Apol\u00f3nia, 5300-253 Bragan\u00e7a, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"9641","DOI":"10.1016\/S1452-3981(23)11207-7","article-title":"Evaluation of Antioxidant Capacity of Propolis Collected in Various Areas of Algeria Using Electrochemical TechniquesInt","volume":"10","author":"Belfar","year":"2015","journal-title":"J. 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