{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,11]],"date-time":"2026-03-11T23:17:44Z","timestamp":1773271064799,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,12,16]],"date-time":"2020-12-16T00:00:00Z","timestamp":1608076800000},"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>The present study aimed to screen plants for bioactive compounds with potential antibacterial activities. In our efforts to evaluate plants from Borneo, we isolated and elucidated the structures of four natural products from the bioactive fraction of a chloroform extract of Goniothalamus longistipetes using various chromatographic and spectroscopic techniques. The bioactive compounds were identified as a known styryllactone, (+)-altholactone ((2S,3R,3aS,7aS)-3-hydroxy-2-phenyl-2,3,3a,7a-tetrahydrobenzo-5(4H)-5-one) (1), a new styryllactone, (2S,3R,3aS,7aS)-3-hydroxy-2-phenyl-2,3,3a,7a-tetrahydrobenzo-5(4H)-5-one) (2) as well as a new alkaloid, 2,6-dimethoxyisonicotinaldehyde (3) and a new alkenyl-5-hydroxyl-phenyl benzoic acid (4). 1 and 4 showed broad-spectrum anti-bacterial activities against Gram-positive and Gram-negative bacteria as well as acid-fast model selected for this study. Compound 2 only demonstrated activities against Gram-positive bacteria whilst 3 displayed selective inhibitory activities against Gram-positive bacterial strains. Additionally, their mechanisms of anti-bacterial action were also investigated. Using Mycobacterium smegmatis as a fast-growing model of tubercle bacilli, compounds 1, 2 and 4 demonstrated inhibitory activities against whole-cell drug efflux and biofilm formation; two key intrinsic mechanisms of antibiotic resistance. Interestingly, the amphiphilic compound 4 exhibited inhibitory activity against the conjugation of plasmid pKM101 in Escherichia coli using a plate conjugation assay. Plasmid conjugation is a mechanism by which Gram-positive and Gram-negative-bacteria acquire drug resistance and virulence. These results indicated that bioactive compounds isolated from Goniothalamus longistipetes can be potential candidates as \u2018hits\u2019 for further optimisation.<\/jats:p>","DOI":"10.3390\/antibiotics9120913","type":"journal-article","created":{"date-parts":[[2020,12,16]],"date-time":"2020-12-16T09:21:15Z","timestamp":1608110475000},"page":"913","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Bioactive Compounds from the Bornean Endemic Plant Goniothalamus longistipetes"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9824-5561","authenticated-orcid":false,"given":"Stephen P.","family":"Teo","sequence":"first","affiliation":[{"name":"Research Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK"},{"name":"Department of Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK"},{"name":"Forest Department Sarawak, Wisma Sumber Alam, Petra Jaya, Kuching 93600, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1165-9295","authenticated-orcid":false,"given":"Sanjib","family":"Bhakta","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, Institute of Structural and Molecular Biology, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paul","family":"Stapleton","sequence":"additional","affiliation":[{"name":"Research Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Simon","family":"Gibbons","sequence":"additional","affiliation":[{"name":"Research Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK"},{"name":"School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"629","DOI":"10.1021\/acs.jnatprod.5b01055","article-title":"Natural products as sources of new drugs from 1981\u20132014","volume":"79","author":"Newman","year":"2016","journal-title":"J. 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