{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T21:30:35Z","timestamp":1773869435877,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,6,7]],"date-time":"2025-06-07T00:00:00Z","timestamp":1749254400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Background\/Objectives: This investigation evaluated 2,6-Dichlorophenolindophenol (DCIP), a redox dye, as a colorimetric reagent for rapid quantification of oral bacteria and examined the antimicrobial effects of oral hygiene formulations. Methods\/Results: Viable microbial cells reduce DCIP, resulting in a loss of its blue color which can be measured spectrophotometrically. Strains of Actinomyces viscosus, Veillonella atypica, Aggregatibacter actinomycetemcomitans, Streptococcus mutans and Candida albicans grown in the laboratory reduced DCIP. Significant correlations between increasing viable plate counts and DCIP reduction were noted for strains of oral organisms. Intact microbial cells reduced DCIP, with insignificant reductions observed by spent microbial media or bacteria free culture media. Organisms inactivated by either heat or cold demonstrated significantly lower DCIP reduction in comparison to metabolically intact organisms grown under optimal conditions. Conclusions: DCIP reduction provided a rapid and accurate method to evaluate antimicrobial effects of clinical proven mouthwashes formulated with cetylpyridinium chloride or chlorhexidine and toothpastes for a range of oral bacteria. Together, these results identify a rapid, low-cost method using common laboratory equipment to enumerate oral organisms with a visual outcome.<\/jats:p>","DOI":"10.3390\/antibiotics14060590","type":"journal-article","created":{"date-parts":[[2025,6,9]],"date-time":"2025-06-09T06:46:01Z","timestamp":1749451561000},"page":"590","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Assessment of Oral Microbial Viability by 2,6-Dichlorophenolindophenol a Redox Agent"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3902-1135","authenticated-orcid":false,"given":"Prem K.","family":"Sreenivasan","sequence":"first","affiliation":[{"name":"HITLAB, 3960 Broadway, New York, NY 10032, USA"},{"name":"Adjunct Faculty, JSS Academy of Higher Education and Research, Mysuru 570 015, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0297-3474","authenticated-orcid":false,"given":"Violet I.","family":"Haraszthy","sequence":"additional","affiliation":[{"name":"Department of Restorative Dentistry, University at Buffalo, Buffalo, NY 14214, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1111\/prd.12330","article-title":"The prevention of periodontal disease\u2014An overview","volume":"84","author":"Scannapieco","year":"2020","journal-title":"Periodontol. 2000"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1111\/prd.12125","article-title":"Improving periodontal outcomes: Merging clinical and behavioral science","volume":"71","author":"Wilder","year":"2016","journal-title":"Periodontol. 2000"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"77","DOI":"10.1034\/j.1600-0757.2001.22250106.x","article-title":"Nonsurgical periodontal therapy","volume":"25","author":"Drisko","year":"2001","journal-title":"Periodontol. 2000"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1111\/j.1600-0757.1995.tb00047.x","article-title":"Chemical agents to prevent and regulate plaque development","volume":"8","author":"Fine","year":"1995","journal-title":"Periodontol. 2000"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"2240","DOI":"10.1208\/s12249-016-0706-9","article-title":"Development of a Sustained Antiplaque and Antimicrobial Chewing Gum of a Decapeptide","volume":"18","author":"Leung","year":"2017","journal-title":"AAPS PharmSciTech"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"145","DOI":"10.2174\/1872211314666200820142509","article-title":"Formulation, Development, and Evaluation of Herbal Effervescent Mouthwash Tablet Containing Azadirachta Indica (Neem) and Curcumin for the Maintenance of Oral Hygiene","volume":"14","author":"Singh","year":"2020","journal-title":"Recent. 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