{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T17:37:44Z","timestamp":1775151464723,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,1,29]],"date-time":"2025-01-29T00:00:00Z","timestamp":1738108800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Foundation for Science and Technology","doi-asserted-by":"publisher","award":["UIDP\/04923\/2020"],"award-info":[{"award-number":["UIDP\/04923\/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>This study examines the biochemical profile of saliva, focusing on flow rate, total protein concentration, and the enzymatic activities of amylase and catalase. The study aims to explore the correlations between these parameters and their response to physiological stress induced by physical activity, providing insights into saliva\u2019s diagnostic potential. Thirty-one participants were recruited, and saliva samples were collected before and after a structured physical activity session. Biochemical parameters were analyzed using established protocols to assess changes induced by exercise. Significant positive correlations were observed between protein concentration and amylase activity, particularly in post-exercise conditions. No significant correlations were found between the salivary flow and enzyme activities. Catalase activity displayed a weaker association with protein levels. These findings suggest that saliva can be a non-invasive biomarker for systemic health and stress responses. The study highlights the diagnostic utility of saliva and underscores the need for further investigations in younger and healthier populations to broaden the applicability of these results.<\/jats:p>","DOI":"10.3390\/ijms26031164","type":"journal-article","created":{"date-parts":[[2025,1,29]],"date-time":"2025-01-29T09:06:38Z","timestamp":1738141598000},"page":"1164","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Analyzing the Biochemistry of Saliva: Flow, Total Protein, Amylase Enzymatic Activity, and Their Interconnections"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5254-7409","authenticated-orcid":false,"given":"Jose A.","family":"Parraca","sequence":"first","affiliation":[{"name":"Departamento de Desporto e Sa\u00fade, Escola de Sa\u00fade e Desenvolvimento Humano, Universidade de \u00c9vora, 7004-516 \u00c9vora, Portugal"},{"name":"Comprehensive Health Research Centre (CHRC), University of \u00c9vora, 7004-516 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3616-7799","authenticated-orcid":false,"given":"Alejandro","family":"Rubio-Zarapuz","sequence":"additional","affiliation":[{"name":"Faculty of Sports Sciences, Universidad Europea de Madrid, Tajo Street, 28670 Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0747-8133","authenticated-orcid":false,"given":"Jos\u00e9 Francisco","family":"Tornero-Aguilera","sequence":"additional","affiliation":[{"name":"Faculty of Sports Sciences, Universidad Europea de Madrid, Tajo Street, 28670 Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2397-2801","authenticated-orcid":false,"given":"Vicente Javier","family":"Clemente-Su\u00e1rez","sequence":"additional","affiliation":[{"name":"Faculty of Sports Sciences, Universidad Europea de Madrid, Tajo Street, 28670 Madrid, Spain"},{"name":"Grupo de Investigaci\u00f3n en Cultura, Educaci\u00f3n y Sociedad, Universidad de la Costa, Barranquilla 080002, Colombia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7780-3942","authenticated-orcid":false,"given":"Pablo","family":"Tomas-Carus","sequence":"additional","affiliation":[{"name":"Departamento de Desporto e Sa\u00fade, Escola de Sa\u00fade e Desenvolvimento Humano, Universidade de \u00c9vora, 7004-516 \u00c9vora, Portugal"},{"name":"Comprehensive Health Research Centre (CHRC), University of \u00c9vora, 7004-516 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3854-9130","authenticated-orcid":false,"given":"Ana Rodrigues","family":"Costa","sequence":"additional","affiliation":[{"name":"Departamento de Ci\u00eancias M\u00e9dicas e da Sa\u00fade, Escola de Sa\u00fade e Desenvolvimento Humano, Universidade de \u00c9vora, 7004-516 \u00c9vora, Portugal"},{"name":"Center for Sci-Tech Research in Earth System and Energy (CREATE) Universidade de \u00c9vora, 7004-516 \u00c9vora, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,29]]},"reference":[{"key":"ref_1","first-page":"449","article-title":"The R\u00f4le of Saliva in Maintaining Oral Health and as an Aid to Diagnosis","volume":"11","year":"2006","journal-title":"Med. 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