{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T10:48:08Z","timestamp":1782902888529,"version":"3.54.5"},"reference-count":43,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T00:00:00Z","timestamp":1782864000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Plants"],"abstract":"<jats:p>Purple carrot peels are an abundant agro-industrial by-product rich in phytochemicals and have potential applications such as natural colorants and antioxidants. In the context of increasing interest in the valorization of vegetable processing residues, the recovery of bioactive compounds from such materials has become an important scientific and industrial objective. This study aimed to optimize the parameters of a solvent extraction process to maximize total anthocyanin content (TAC), total polyphenol content (TPC), and antioxidant activity (AA) from purple carrot peels. A Central Composite Design, combined with response surface methodology, was used to evaluate the effects of temperature, extraction time, ethanol concentration, and pH across 30 experimental runs. The optimal extraction conditions were identified as pH 4, an ethanol concentration of 50%, a temperature of 80 \u00b0C, and an extraction time of 35.88 min. Under the optimized extraction conditions, the experimental values obtained for TAC, TPC, and AA were 2.10 mg C3G\/g D.W., 20.60 mg GAE\/g D.W, and 19.02 mMol Trolox\/g D.W, respectively, which were in close agreement with the predicted values of 2.10 mg C3G\/g D.W., 20.30 mg GAE\/g D.W, and 19.05 mMol Trolox\/g D.W. The good agreement between predicted and experimental values confirmed the adequacy and predictive capability of the developed response surface models. A total of 32 phenolic compounds were characterized by UHPLC\u2013MS\/MS, with shikimic acid identified as the dominant compound, highlighting the chemical diversity and abundance of bioactive phenolics in purple carrot peels. The results demonstrate that optimization of extraction parameters significantly enhances the efficiency of conventional solid\u2013liquid extraction, enabling the effective recovery of antioxidant compounds. The proposed approach supports the sustainable valorization of purple carrot by-products as cost-effective sources of natural pigments for food industry applications.<\/jats:p>","DOI":"10.3390\/plants15132036","type":"journal-article","created":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T08:19:02Z","timestamp":1782893942000},"page":"2036","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Phytochemical Recovery from Purple Carrot Peels: Optimization and Characterization"],"prefix":"10.3390","volume":"15","author":[{"given":"Alexandra Teodora","family":"Gheorghe (M\u0103rtin)","sequence":"first","affiliation":[{"name":"Department of Food Science, Engineering and Applied Biotechnology, Faculty of Food Science and Engineering, Dunarea de Jos University of Galati, 111 Domneasc\u0103 Street, 800201 Galati, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6702-3424","authenticated-orcid":false,"given":"Oana Emilia","family":"Constantin","sequence":"additional","affiliation":[{"name":"Department of Food Science, Engineering and Applied Biotechnology, Faculty of Food Science and Engineering, Dunarea de Jos University of Galati, 111 Domneasc\u0103 Street, 800201 Galati, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4909-8574","authenticated-orcid":false,"given":"Elisabeta-Irina","family":"Gean\u0103","sequence":"additional","affiliation":[{"name":"National R&D Institute for Cryogenics and Isotopic Technologies-ICSI R\u00e2mnicu V\u00e2lcea, 4th Uzinei Street, 240050 R\u00e2mnicu V\u00e2lcea, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4549-5399","authenticated-orcid":false,"given":"Doina Georgeta","family":"Andronoiu","sequence":"additional","affiliation":[{"name":"Department of Food Science, Engineering and Applied Biotechnology, Faculty of Food Science and Engineering, Dunarea de Jos University of Galati, 111 Domneasc\u0103 Street, 800201 Galati, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicoleta","family":"St\u0103nciuc","sequence":"additional","affiliation":[{"name":"Department of Food Science, Engineering and Applied Biotechnology, Faculty of Food Science and Engineering, Dunarea de Jos University of Galati, 111 Domneasc\u0103 Street, 800201 Galati, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2215-6826","authenticated-orcid":false,"given":"Iuliana","family":"Aprodu","sequence":"additional","affiliation":[{"name":"Department of Food Science, Engineering and Applied Biotechnology, Faculty of Food Science and Engineering, Dunarea de Jos University of Galati, 111 Domneasc\u0103 Street, 800201 Galati, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7512-2422","authenticated-orcid":false,"given":"Claudia","family":"Mure\u0219an","sequence":"additional","affiliation":[{"name":"Faculty of Food Engineering, Tourism and Environmental Protection, Aurel Vlaicu University of Arad, 2 Elena, Dragoi Street, 310330 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Constantin","family":"Croitoru","sequence":"additional","affiliation":[{"name":"Department of Food Science, Engineering and Applied Biotechnology, Faculty of Food Science and Engineering, Dunarea de Jos University of Galati, 111 Domneasc\u0103 Street, 800201 Galati, Romania"},{"name":"Academy of Agricultural and Forestry Sciences, 61 M\u0103ra\u0219ti Blvd, 011464 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5804-2786","authenticated-orcid":false,"given":"Gabriela","family":"R\u00e2peanu","sequence":"additional","affiliation":[{"name":"Department of Food Science, Engineering and Applied Biotechnology, Faculty of Food Science and Engineering, Dunarea de Jos University of Galati, 111 Domneasc\u0103 Street, 800201 Galati, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"223","DOI":"10.1111\/j.1541-4337.2009.00103.x","article-title":"Carrots of Many Colors Provide Basic Nutrition and Bioavailable Phytochemicals Acting as a Functional Food","volume":"9","author":"Arscott","year":"2010","journal-title":"Compr. 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