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In addition, Toombak samples were examined for viable microorganisms, tested for antibacterial activity against selected reference strains, and the results were statistically analyzed using the Wilcoxon rank-sum test (\u03b1\u2009=\u20090.05).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      The overall bacterial counts, diversity, and species distribution showed no statistically significant differences between users and non-users, with the exception of\n                      <jats:italic>Schaalia odontolytica<\/jats:italic>\n                      (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.0306) and the proportion of Gram-positive rods (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.0137) expressed as percentages, which were more frequent in the control group. Toombak itself harbored mainly\n                      <jats:italic>Bacillus<\/jats:italic>\n                      spp., and no inhibitory activity against the tested bacteria was observed. While a non-significant trend toward lower bacterial counts was observed in Toombak users (1.83\u2009\u00d7\u200910\u2078 vs. 3.31\u2009\u00d7\u200910\u2078 CFU\/ml), this finding should be interpreted cautiously given the exploratory design and substantial interindividual variability.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Further studies using larger cohorts and culture-independent methods are warranted to better clarify its microbial impact.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s00784-026-07094-1","type":"journal-article","created":{"date-parts":[[2026,8,22]],"date-time":"2026-08-22T08:04:35Z","timestamp":1787385875000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Impact of sudanese chewing tobacco toombak on oral bacteria \u2013 a culture-based pilot study"],"prefix":"10.1007","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-8688-2886","authenticated-orcid":false,"given":"David L.","family":"Auer","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fadil","family":"Elamin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Konstantin J.","family":"Scholz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Duc","family":"Pham","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Annette","family":"Wittmer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elmar","family":"Hellwig","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fabian","family":"Cieplik","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ali","family":"Al-Ahmad","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,8,22]]},"reference":[{"key":"7094_CR1","unstructured":"World Health Organisation (2025) WHO report on the global tobacco epidemic, 2025. 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