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After several chromatographic steps, triterpene saponins of the lupane and oleanane types were identified as the bioactive principles. In total, eight new triterpene saponins (1\u20138) with four so far undescribed aglycone structures were isolated and characterized via HRESIMS, GC-MS, and 1D and 2D NMR spectroscopy. Their anti-influenza virus activity on HK\/68 and the 2009 pandemic H1N1 strain A\/Jena\/8178\/09 revealed the most potent effects by compounds 7 and 8, with IC50 values between 0.05 and 0.27 \u03bcM. This is the first time triterpene saponins have been reported as constituents of the investigated plant material.<\/jats:p>","DOI":"10.1021\/acs.jnatprod.7b00774","type":"journal-article","created":{"date-parts":[[2018,2,2]],"date-time":"2018-02-02T12:18:20Z","timestamp":1517573900000},"page":"515-523","source":"Crossref","is-referenced-by-count":50,"title":["Anti-Influenza Triterpene Saponins from the Bark of\n                    <i>Burkea africana<\/i>"],"prefix":"10.1021","volume":"81","author":[{"given":"Christina E.","family":"Mair","sequence":"first","affiliation":[{"name":"University of Vienna , , Althanstra\u00dfe 14 , ,","place":["Vienna, Austria, 1090"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0305-9270","authenticated-orcid":true,"given":"Ulrike","family":"Grienke","sequence":"additional","affiliation":[{"name":"University of Vienna , , Althanstra\u00dfe 14 , ,","place":["Vienna, Austria, 1090"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4561-5589","authenticated-orcid":true,"given":"Anke","family":"Wilhelm","sequence":"additional","affiliation":[{"name":"University of the Free State , , PO Box 339, ,","place":["Bloemfontein, South Africa, 9300"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ernst","family":"Urban","sequence":"additional","affiliation":[{"name":"University of Vienna , , Althanstra\u00dfe 14 , ,","place":["Vienna, Austria, 1090"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9685-0373","authenticated-orcid":true,"given":"Martin","family":"Zehl","sequence":"additional","affiliation":[{"name":"University of Vienna , , Althanstra\u00dfe 14 , ,","place":["Vienna, Austria, 1090"]},{"name":"University of Vienna , , Althanstra\u00dfe 14 , ,","place":["Vienna, Austria, 1090"]},{"name":"University of Vienna , , Wa\u0308hringer Stra\u00dfe 38 , ,","place":["Vienna, Austria, 1090"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michaela","family":"Schmidtke","sequence":"additional","affiliation":[{"name":"Institute of Medical Microbiology, Section Experimental Virology, Jena University Hospital , Hans-Kno\u0308ll-Stra\u00dfe 2 , ,","place":["Jena, Germany, 07745"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6581-0774","authenticated-orcid":true,"given":"Judith M.","family":"Rollinger","sequence":"additional","affiliation":[{"name":"University of Vienna , , Althanstra\u00dfe 14 , ,","place":["Vienna, Austria, 1090"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2018,2,2]]},"reference":[{"key":"2026090222392178000_cit1","unstructured":"Houe\u0301rou, L.\n          \n          http:\/\/www.fao.org\/ag\/agp\/agpc\/doc\/GBASE\/data\/pf000374.htm,\naccessed on 10\/07\/17."},{"key":"2026090222392178000_cit2","first-page":"182","volume-title":"People\u2019s Plants.\nA Guide to Useful Plants of Southern Africa","author":"van Wyk","year":"2007"},{"key":"2026090222392178000_cit3","first-page":"122","volume":"3","author":"Tanko","year":"2011","journal-title":"Arch. 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