{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T03:00:39Z","timestamp":1776740439376,"version":"3.51.2"},"reference-count":57,"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":[{"name":"Amyris Bio Products Portugal Unipessoal Lda","award":["POCI-01-0247-FEDER-027578"],"award-info":[{"award-number":["POCI-01-0247-FEDER-027578"]}]},{"name":"Escola Superior de Biotecnologia - Universidade Catolica Portuguesa, Porto","award":["POCI-01-0247-FEDER-027578"],"award-info":[{"award-number":["POCI-01-0247-FEDER-027578"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Fermentation"],"abstract":"<jats:p>The use of fecal inoculums for in vitro fermentation models requires a viable gut microbiota, capable of fermenting the unabsorbed nutrients. Fresh samples from human donors are used; however, the availability of fresh fecal inoculum and its inherent variability is often a problem. This study aimed to optimize a method of preserving pooled human fecal samples for in vitro fermentation studies. Different conditions and times of storage at \u221220 \u00b0C were tested. In vitro fermentation experiments were carried out for both fresh and frozen inoculums, and the metabolic profile compared. In comparison with the fresh, the inoculum frozen in a PBS and 30% glycerol solution, had a significantly lower (p &lt; 0.05) bacterial count (&lt;1 log CFU\/mL). However, no significant differences (p &lt; 0.05) were found between the metabolic profiles after 48 h. Hence, a PBS and 30% glycerol solution can be used to maintain the gut microbiota viability during storage at \u221220 \u00b0C for at least 3 months, without interfering with the normal course of colonic fermentation.<\/jats:p>","DOI":"10.3390\/fermentation7010014","type":"journal-article","created":{"date-parts":[[2021,1,21]],"date-time":"2021-01-21T02:36:05Z","timestamp":1611196565000},"page":"14","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":39,"title":["Preservation of Human Gut Microbiota Inoculums for In Vitro Fermentations Studies"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8691-8255","authenticated-orcid":false,"given":"Nelson Mota","family":"de Carvalho","sequence":"first","affiliation":[{"name":"CBQF-Centro de Biotecnologia e Qu\u00edmica Fina-Laborat\u00f3rio Associado, Escola Superior de Biotecnologia, Universidade Cat\u00f3lica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1412-0655","authenticated-orcid":false,"given":"Diana Luazi","family":"Oliveira","sequence":"additional","affiliation":[{"name":"CBQF-Centro de Biotecnologia e Qu\u00edmica Fina-Laborat\u00f3rio Associado, Escola Superior de Biotecnologia, Universidade Cat\u00f3lica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal"},{"name":"Amyris Bio Products Portugal, Unipessoal Lda, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal"}]},{"given":"Mayra Anton","family":"Dib Saleh","sequence":"additional","affiliation":[{"name":"CBQF-Centro de Biotecnologia e Qu\u00edmica Fina-Laborat\u00f3rio Associado, Escola Superior de Biotecnologia, Universidade Cat\u00f3lica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal"}]},{"given":"Manuela","family":"Pintado","sequence":"additional","affiliation":[{"name":"CBQF-Centro de Biotecnologia e Qu\u00edmica Fina-Laborat\u00f3rio Associado, Escola Superior de Biotecnologia, Universidade Cat\u00f3lica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal"}]},{"given":"Ana Raquel","family":"Madureira","sequence":"additional","affiliation":[{"name":"CBQF-Centro de Biotecnologia e Qu\u00edmica Fina-Laborat\u00f3rio Associado, Escola Superior de Biotecnologia, Universidade Cat\u00f3lica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Maki, J.J., Klima, C.L., Sylte, M.J., and Looft, T. 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