{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,9]],"date-time":"2026-03-09T14:28:35Z","timestamp":1773066515750,"version":"3.50.1"},"reference-count":39,"publisher":"Oxford University Press (OUP)","issue":"7","license":[{"start":{"date-parts":[[2020,3,19]],"date-time":"2020-03-19T00:00:00Z","timestamp":1584576000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"funder":[{"DOI":"10.13039\/100000199","name":"U.S. Department of Agriculture","doi-asserted-by":"publisher","award":["3020\u201343440-001\u201300D"],"award-info":[{"award-number":["3020\u201343440-001\u201300D"]}],"id":[{"id":"10.13039\/100000199","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100007765","name":"Kansas State University","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100007765","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2020,4,1]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>Polyphenols derived from a variety of plants have demonstrated antimicrobial activity against diverse microbial pathogens. Legionella pneumophila is an intracellular bacterial pathogen that opportunistically causes a severe inflammatory pneumonia in humans, called Legionnaires\u2019 Disease, via replication within macrophages. Previous studies demonstrated that tea polyphenols attenuate L. pneumophila intracellular replication within mouse macrophages via increased tumor necrosis factor (TNF) production. Sorghum bicolor is a sustainable cereal crop that thrives in arid environments and is well-suited to continued production in warming climates. Sorghum polyphenols have anticancer and antioxidant properties, but their antimicrobial activity has not been evaluated. Here, we investigated the impact of sorghum polyphenols on L. pneumophila intracellular replication within RAW 264.7 mouse macrophages. Sorghum high-polyphenol extract (HPE) attenuated L. pneumophila intracellular replication in a dose-dependent manner but did not impair either bacterial replication in rich media or macrophage viability. Moreover, HPE treatment enhanced both TNF and IL-6 secretion from L. pneumophila infected macrophages. Thus, polyphenols derived from sorghum enhance macrophage restriction of L. pneumophila, likely via increased pro-inflammatory cytokine production. This work reveals commonalities between plant polyphenol-mediated antimicrobial activity and provides a foundation for future evaluation of sorghum as an antimicrobial agent.<\/jats:p>","DOI":"10.1093\/femsle\/fnaa053","type":"journal-article","created":{"date-parts":[[2020,3,18]],"date-time":"2020-03-18T00:38:30Z","timestamp":1584491910000},"source":"Crossref","is-referenced-by-count":10,"title":["High-polyphenol extracts from\n                    <i>Sorghum bicolor<\/i>\n                    attenuate replication of\n                    <i>Legionella pneumophila<\/i>\n                    within RAW 264.7 macrophages"],"prefix":"10.1093","volume":"367","author":[{"given":"Aubrey K","family":"Gilchrist","sequence":"first","affiliation":[{"name":"Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, Kansas, 66506 USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dmitriy","family":"Smolensky","sequence":"additional","affiliation":[{"name":"Grain Quality and Structure Research Unit, Agricultural Research Service, U.S. Department of Agriculture, 1515 College Avenue, Manhattan, Kansas, 66506 USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tshegofatso","family":"Ngwaga","sequence":"additional","affiliation":[{"name":"Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, Kansas, 66506 USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Deepika","family":"Chauhan","sequence":"additional","affiliation":[{"name":"Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, Kansas, 66506 USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sarah","family":"Cox","sequence":"additional","affiliation":[{"name":"Grain Quality and Structure Research Unit, Agricultural Research Service, U.S. Department of Agriculture, 1515 College Avenue, Manhattan, Kansas, 66506 USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ramasamy","family":"Perumal","sequence":"additional","affiliation":[{"name":"Kansas State University Agricultural Research Center, 1232 240th Avenue, Hays, Kansas, 67601 USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Leela E","family":"Noronha","sequence":"additional","affiliation":[{"name":"Arthropod-borne Animal Disease Research Unit, Agricultural Research Service, U. 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