{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,27]],"date-time":"2026-05-27T22:11:48Z","timestamp":1779919908693,"version":"3.53.1"},"reference-count":37,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,19]],"date-time":"2021-01-19T00:00:00Z","timestamp":1611014400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100009888","name":"Regione Toscana","doi-asserted-by":"publisher","award":["\u2018Erbi Boni\u2019 project, funded by FEASR Reg. UE 1305\/2013 \u2013 PSR 2014\/2020 - Regione Toscana Mis. 19 \u2013 GAL MontagnAppennino Mis. 16.2"],"award-info":[{"award-number":["\u2018Erbi Boni\u2019 project, funded by FEASR Reg. UE 1305\/2013 \u2013 PSR 2014\/2020 - Regione Toscana Mis. 19 \u2013 GAL MontagnAppennino Mis. 16.2"]}],"id":[{"id":"10.13039\/501100009888","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Horticulturae"],"abstract":"<jats:p>Stinging nettle (Urtica dioica) is a plant well known in traditional medicine for its many beneficial properties, but the lack of standardization regarding the product to offer to consumers limits its diffusion. To this end, drying appears to be a useful technique to offer a low-cost product that can be stored for long time, but the different drying procedures may give rise to end-products of very different quality as nutraceutical and antioxidant compounds. Nettle leaves have been dehydrated employing freeze-drying (FD), oven-drying (OD) or heat pump drying (HPD) and compared with fresh leaves following water extraction to emulate the use by final consumers. Results indicate that the best dehydration technique is HPD, which apparently gives rise to more than a doubling of total phenols and antioxidant activity in the extract compared to the water extract obtained from fresh leaves but a reduction in the level of ascorbic acid of about 39%. In addition, the content of some phenolic compounds is 10 to over a hundred times higher in the extract after HPD than that obtained from fresh samples. This confirms that the dehydration technique should be tuned in relation to the compounds of greatest interest or value.<\/jats:p>","DOI":"10.3390\/horticulturae7010010","type":"journal-article","created":{"date-parts":[[2021,1,19]],"date-time":"2021-01-19T04:55:31Z","timestamp":1611032131000},"page":"10","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":66,"title":["Effect of Drying Methods on Phenolic Compounds and Antioxidant Activity of Urtica dioica L. Leaves"],"prefix":"10.3390","volume":"7","author":[{"given":"Leani Mart\u00ecnez","family":"Garc\u00eca","sequence":"first","affiliation":[{"name":"Grupo Tecnico Nacional de Plantas Medicinales de la Asociacion Cubana de Tecnicos Agricolas Agroforestales (ACTAF), Calle 98, Esquina 7ma, Playa, La Habana 11300, Cuba"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2553-8221","authenticated-orcid":false,"given":"Costanza","family":"Ceccanti","sequence":"additional","affiliation":[{"name":"Department of Agriculture, Food and Environment, University of Pisa, 56124 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6981-2216","authenticated-orcid":false,"given":"Carmine","family":"Negro","sequence":"additional","affiliation":[{"name":"Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6047-3526","authenticated-orcid":false,"given":"Luigi","family":"De Bellis","sequence":"additional","affiliation":[{"name":"Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9994-763X","authenticated-orcid":false,"given":"Luca","family":"Incrocci","sequence":"additional","affiliation":[{"name":"Department of Agriculture, Food and Environment, University of Pisa, 56124 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9927-4017","authenticated-orcid":false,"given":"Alberto","family":"Pardossi","sequence":"additional","affiliation":[{"name":"Department of Agriculture, Food and Environment, University of Pisa, 56124 Pisa, Italy"},{"name":"Interdepartmental Research Center Nutrafood \u201cNutraceuticals and Food for Health\u201d, University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2472-720X","authenticated-orcid":false,"given":"Lucia","family":"Guidi","sequence":"additional","affiliation":[{"name":"Department of Agriculture, Food and Environment, University of Pisa, 56124 Pisa, Italy"},{"name":"Interdepartmental Research Center Nutrafood \u201cNutraceuticals and Food for Health\u201d, University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1016\/j.pbiomolbio.2019.05.008","article-title":"Screening of pharmacological uses of Urtica dioica and others benefits","volume":"150","author":"Dhouibi","year":"2020","journal-title":"Prog. 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