{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T23:36:21Z","timestamp":1790811381052,"version":"4.1.0"},"reference-count":49,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2022,4,29]],"date-time":"2022-04-29T00:00:00Z","timestamp":1651190400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Quaris Srl to E.V.","award":["LIB_VT17EVERD_01"],"award-info":[{"award-number":["LIB_VT17EVERD_01"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Glycomacropeptide (GMP) represents a good alternative protein source in Phenylketonuria (PKU). In a mouse model, it has been suggested to exert a prebiotic role on beneficial gut bacteria. In this study, we performed the 16S rRNA sequencing to evaluate the effect of 6 months of GMP supplementation on the gut microbiota of nine PKU patients, comparing their bacterial composition and clinical parameters before and after the intervention. GMP seems to be safe from both the microbiological and the clinical point of view. Indeed, we did not observe dramatic changes in the gut microbiota but a specific prebiotic effect on the butyrate-producer Agathobacter spp. and, to a lesser extent, of Subdoligranulum. Clinically, GMP intake did not show a significant impact on both metabolic control, as phenylalanine values were kept below the age target and nutritional parameters. On the other hand, an amelioration of calcium phosphate homeostasis was observed, with an increase in plasmatic vitamin D and a decrease in alkaline phosphatase. Our results suggest GMP as a safe alternative in the PKU diet and its possible prebiotic role on specific taxa without causing dramatic changes in the commensal microbiota.<\/jats:p>","DOI":"10.3390\/nu14091883","type":"journal-article","created":{"date-parts":[[2022,5,2]],"date-time":"2022-05-02T07:08:58Z","timestamp":1651475338000},"page":"1883","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":46,"title":["Glycomacropeptide Safety and Its Effect on Gut Microbiota in Patients with Phenylketonuria: A Pilot Study"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4875-6179","authenticated-orcid":false,"given":"Chiara","family":"Montanari","sequence":"first","affiliation":[{"name":"Department of Pediatrics, Vittore Buzzi Children\u2019s Hospital, University of Milan, 20154 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3824-7239","authenticated-orcid":false,"given":"Camilla","family":"Ceccarani","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Technologies, National Research Council, 20090 Segrate, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4578-0066","authenticated-orcid":false,"given":"Antonio","family":"Corsello","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Vittore Buzzi Children\u2019s Hospital, University of Milan, 20154 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juri","family":"Zuvadelli","sequence":"additional","affiliation":[{"name":"Clinical Department of Pediatrics, ASST Santi Paolo e Carlo, San Paolo Hospital, University of Milan, 20142 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3839-2698","authenticated-orcid":false,"given":"Emerenziana","family":"Ottaviano","sequence":"additional","affiliation":[{"name":"Department of Health Science, University of Milan, 20142 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7359-8558","authenticated-orcid":false,"given":"Michele","family":"Dei Cas","sequence":"additional","affiliation":[{"name":"Department of Health Science, University of Milan, 20142 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giuseppe","family":"Banderali","sequence":"additional","affiliation":[{"name":"Clinical Department of Pediatrics, ASST Santi Paolo e Carlo, San Paolo Hospital, University of Milan, 20142 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2795-9874","authenticated-orcid":false,"given":"Gianvincenzo","family":"Zuccotti","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Vittore Buzzi Children\u2019s Hospital, University of Milan, 20154 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1893-0455","authenticated-orcid":false,"given":"Elisa","family":"Borghi","sequence":"additional","affiliation":[{"name":"Department of Health Science, University of Milan, 20142 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2111-3111","authenticated-orcid":false,"given":"Elvira","family":"Verduci","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Vittore Buzzi Children\u2019s Hospital, University of Milan, 20154 Milan, Italy"},{"name":"Department of Health Science, University of Milan, 20142 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1038\/gim.2013.179","article-title":"Recommendations for the Nutrition Management of Phenylalanine Hydroxylase Deficiency","volume":"16","author":"Singh","year":"2014","journal-title":"Genet. 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