{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T03:38:01Z","timestamp":1791430681063,"version":"4.3.3"},"reference-count":49,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,3,19]],"date-time":"2023-03-19T00:00:00Z","timestamp":1679184000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fundo de Incentivo \u00e0 Pesquisa e Eventos","award":["20190413"],"award-info":[{"award-number":["20190413"]}]},{"name":"Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior (CAPES)","award":["20190413"],"award-info":[{"award-number":["20190413"]}]},{"name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico (CNPq)","award":["20190413"],"award-info":[{"award-number":["20190413"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>The composition of the gut microbiota oscillates according to the light\u2013dark cycle. However, the existing literature demonstrates these oscillations only by molecular methods. Microbial cultures are an interesting method for studying metabolically active microorganisms. In this work, we aimed to understand the diurnal oscillation of the intestinal microbiota in Wistar male rats through microbial culture analysis. Over a 24 h period, three animals were euthanized every 6 h. Intestinal segments were dissected immediately after euthanasia and diluted in phosphate-buffered saline (PBS) for plating in different culture media. The CFU\/mL counts in feces samples cultured in the Brucella medium were significantly higher at ZT0, followed by ZT6, ZT18, and ZT12 (p = 0.0156), which demonstrated the diurnal oscillation of metabolically active anaerobic bacteria every 6 h using microbial culture. In addition, quantitative differences were demonstrated in anaerobic bacteria and fungi in different gastrointestinal tract tissues.<\/jats:p>","DOI":"10.3390\/life13030831","type":"journal-article","created":{"date-parts":[[2023,3,20]],"date-time":"2023-03-20T06:48:35Z","timestamp":1679294915000},"page":"831","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Understanding the Diurnal Oscillation of the Gut Microbiota Using Microbial Culture"],"prefix":"10.3390","volume":"13","author":[{"given":"Guilherme","family":"Amando","sequence":"first","affiliation":[{"name":"Chronobiology and Sleep Laboratory, Hospital de Cl\u00ednicas de Porto Alegre (HCPA), Porto Alegre 90410-000, Brazil"},{"name":"Graduate Program in Psychiatry and Behavioral Sciences, Faculty of Medical Sciences, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre 90410-000, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andr\u00e9","family":"Tonon","sequence":"additional","affiliation":[{"name":"Chronobiology and Sleep Laboratory, Hospital de Cl\u00ednicas de Porto Alegre (HCPA), Porto Alegre 90410-000, Brazil"},{"name":"Graduate Program in Psychiatry and Behavioral Sciences, Faculty of Medical Sciences, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre 90410-000, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D\u00e9bora","family":"Constantino","sequence":"additional","affiliation":[{"name":"Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Paz","family":"Hidalgo","sequence":"additional","affiliation":[{"name":"Chronobiology and Sleep Laboratory, Hospital de Cl\u00ednicas de Porto Alegre (HCPA), Porto Alegre 90410-000, Brazil"},{"name":"Graduate Program in Psychiatry and Behavioral Sciences, Faculty of Medical Sciences, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre 90410-000, Brazil"},{"name":"Department of Psychiatry and Legal Medicine, Faculty of Medical Sciences, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre 90410-000, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8992-9697","authenticated-orcid":false,"given":"Pabulo Henrique","family":"Rampelotto","sequence":"additional","affiliation":[{"name":"Graduate Program in Pharmacology and Therapeutics, Institute of Health Sciences, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre 90410-000, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francisco","family":"Montagner","sequence":"additional","affiliation":[{"name":"Graduate Program in Psychiatry and Behavioral Sciences, Faculty of Medical Sciences, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre 90410-000, Brazil"},{"name":"Graduate Program in Dentistry, Faculty of Dental Sciences, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre 90410-000, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1101\/SQB.1960.025.01.004","article-title":"Exogenous and Endogenous Components in Circadian Rhythms","volume":"25","author":"Aschoff","year":"1960","journal-title":"Cold Spring Harb. 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