{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T14:47:42Z","timestamp":1787064462130,"version":"build-2736575974"},"reference-count":53,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2022,6,20]],"date-time":"2022-06-20T00:00:00Z","timestamp":1655683200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100009687","name":"Wroclaw Medical University","doi-asserted-by":"publisher","award":["SUB.D110.21.101"],"award-info":[{"award-number":["SUB.D110.21.101"]}],"id":[{"id":"10.13039\/501100009687","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Poplar bark and leaves can be an attractive source of salicylates and other biologically active compounds used in medicine. However, the biochemical variability of poplar material requires a standardization prior to processing. The official analytical protocols used in the pharmaceutical industry rely on the extraction of active compounds, which makes their determination long and costly. An analysis of plant materials in their native state can be performed using vibrational spectroscopy. This paper presents for the first time a comparison of diffuse reflectance in the near- and mid-infrared regions, attenuated total reflection, and Raman spectroscopy used for the simultaneous determination of salicylates and flavonoids in poplar bark and leaves. Based on 185 spectra of various poplar species and hybrid powdered samples, partial least squares regression models, characterized by the relative standard errors of prediction in the 4.5\u20139.9% range for both calibration and validation sets, were developed. These models allow for fast and precise quantification of the studied active compounds in poplar bark and leaves without any chemical sample treatment.<\/jats:p>","DOI":"10.3390\/molecules27123954","type":"journal-article","created":{"date-parts":[[2022,6,21]],"date-time":"2022-06-21T04:39:55Z","timestamp":1655786395000},"page":"3954","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Quantification of Salicylates and Flavonoids in Poplar Bark and Leaves Based on IR, NIR, and Raman Spectra"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8096-5229","authenticated-orcid":false,"given":"Sylwester","family":"Mazurek","sequence":"first","affiliation":[{"name":"Department of Chemistry, University of Wroc\u0142aw, 14 F. Joliot-Curie, 50-383 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8437-2711","authenticated-orcid":false,"given":"Maciej","family":"W\u0142odarczyk","sequence":"additional","affiliation":[{"name":"Department of Pharmacognosy and Herbal Medicines, Faculty of Pharmacy, Wroclaw Medical University, 211a Borowska, 50-556 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sonia","family":"Pielorz","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Wroc\u0142aw, 14 F. Joliot-Curie, 50-383 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5795-8605","authenticated-orcid":false,"given":"Piotr","family":"Oki\u0144czyc","sequence":"additional","affiliation":[{"name":"Department of Pharmacognosy and Herbal Medicines, Faculty of Pharmacy, Wroclaw Medical University, 211a Borowska, 50-556 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7368-1076","authenticated-orcid":false,"given":"Piotr M.","family":"Ku\u015b","sequence":"additional","affiliation":[{"name":"Department of Pharmacognosy and Herbal Medicines, Faculty of Pharmacy, Wroclaw Medical University, 211a Borowska, 50-556 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriela","family":"D\u0142ugosz","sequence":"additional","affiliation":[{"name":"Department of Pharmacognosy and Herbal Medicines, Faculty of Pharmacy, Wroclaw Medical University, 211a Borowska, 50-556 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diana","family":"Vidal-Ya\u00f1ez","sequence":"additional","affiliation":[{"name":"Department of Pharmacognosy and Herbal Medicines, Faculty of Pharmacy, Wroclaw Medical University, 211a Borowska, 50-556 Wroc\u0142aw, Poland"},{"name":"Faculty of Pharmacy, University of Barcelona, Joan XXIII, 27-31, 08014 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5436-7284","authenticated-orcid":false,"given":"Roman","family":"Szostak","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Wroc\u0142aw, 14 F. Joliot-Curie, 50-383 Wroc\u0142aw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1497","DOI":"10.1016\/j.phytochem.2011.01.038","article-title":"Phenolic glycosides of the Salicaceae and their role as anti-herbivore defenses","volume":"72","author":"Boeckler","year":"2011","journal-title":"Phytochemistry"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1083","DOI":"10.1023\/A:1023821304656","article-title":"In vitro degradation of willow salicylates","volume":"29","author":"Ruuhola","year":"2003","journal-title":"J. Chem. Ecol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"348","DOI":"10.1007\/s10354-007-0437-3","article-title":"Willow bark extract: The contribution of polyphenols to the overall effect","volume":"157","author":"Nahrstedt","year":"2007","journal-title":"Wien Med. 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