{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T10:09:24Z","timestamp":1788775764726,"version":"build-2803163510"},"reference-count":41,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T00:00:00Z","timestamp":1788739200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Indonesian Endowment Fund for Education (LPDP) on behalf of the Indonesian Ministry of Higher Education, Science and Technology of the Republic Indonesia","award":["4297\/B3\/DT.03.08\/2025"],"award-info":[{"award-number":["4297\/B3\/DT.03.08\/2025"]}]},{"name":"Indonesian Endowment Fund for Education (LPDP) on behalf of the Indonesian Ministry of Higher Education, Science and Technology of the Republic Indonesia","award":["42011\/IT3\/HK.07.00-4\/P\/B\/2025"],"award-info":[{"award-number":["42011\/IT3\/HK.07.00-4\/P\/B\/2025"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Mar. Drugs","Marine Drugs"],"abstract":"<jats:p>Manzamine alkaloids are a structurally diverse class of marine-derived alkaloids that have attracted considerable interest because of their complex polycyclic architectures, diverse biological activities, and distinctive biosynthetic features. The Indonesian marine sponge Acanthostrongylophora ingens is a particularly rich source of these alkaloids, providing an opportunity to further explore their chemical diversity, biosynthetic relationships, and biological properties. Detailed analyses of LC-HR-ESI-MS\/MS and molecular networking were performed on EtOAc layers obtained from H2O\/EtOAc partitioning of methanolic extracts of the marine sponge, Acanthostrongylophora ingens, collected from Raja Ampat (Southwest Papua), the Thousand Islands reef complex (Jakarta Special Region), Spermonde Archipelago (South Sulawesi), and Sangiang Island (Banten). This approach revealed the presence of both known and new manzamine alkaloids, along with their possible precursors and structural modifications, thereby supporting the proposed biosynthetic origin of these alkaloids. In addition, three flexible cytotoxic manzamine alkaloids, namely (+)-manzamine A hydrochloride (1), (+)-manzamine B (2), and (+)-32,33-dihydro-31-hydroxymanzamine A (3), were purified and their relative configurations determined using quantum mechanic NMR-based calculations and validated by X-ray analysis. (+)-Manzamine A hydrochloride (1) displayed the most potent cytotoxic activities against Artemia salina larvae (LC50 value of 0.041 \u00b1 0.012 \u00b5M) and HEK293T cells (IC50 value of 0.599 \u00b1 0.057 \u00b5M). The potent cytotoxic activity suggested the importance of azocine ring (Z-olefin at C32\u2013C33) in 1. Molecular mechanisms of 1\u20133 were subsequently revealed through computational approaches identifying GSK-3\u03b2 as a potential target. Docking results indicated that 3 possessed better binding affinity to GSK-3\u03b2, compared with other ligands. All isolated manzamines (1\u20133) were found to be stable in the binding site. A molecular mechanism is also proposed to provide insights into how manzamines interrupt cancer cells by targeting specifically with GSK-3\u03b2.<\/jats:p>","DOI":"10.3390\/md24090313","type":"journal-article","created":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T09:23:37Z","timestamp":1788773017000},"page":"313","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Proposed Biosynthesis and Molecular Targets of Manzamine Alkaloids from Acanthostrongylophora ingens (Phylum Porifera: Class Demospongiae)"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9570-3750","authenticated-orcid":false,"given":"Novriyandi","family":"Hanif","sequence":"first","affiliation":[{"name":"Department of Chemistry, Faculty of Mathematics and Natural Sciences, IPB University, Bogor 16680, Indonesia"},{"name":"Tropical Biopharmaca Research Center, IPB University, Bogor 16128, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"}]},{"given":"Ritha Lusian","family":"Karuwal","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Faculty of Mathematics and Natural Sciences, IPB University, Bogor 16680, Indonesia"},{"name":"Tropical Biopharmaca Research Center, IPB University, Bogor 16128, Indonesia"},{"name":"Biology Education Program, Faculty of Teaching and Education, University of Pattimura, Ambon 97233, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"}]},{"given":"Muhammad Naufal Khotmi Ramadhan Ashari Jaya","family":"Sudrajat","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Faculty of Mathematics and Natural Sciences, IPB University, Bogor 16680, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1555-9507","authenticated-orcid":false,"given":"Didik Huswo","family":"Utomo","sequence":"additional","affiliation":[{"name":"Bioinformatics Research Center, Indonesian Institute of Bioinformatics (INBIO Indonesia), Malang 65145, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"}]},{"given":"Gibral Abdul","family":"Khalik","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Faculty of Mathematics and Natural Sciences, IPB University, Bogor 16680, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"}]},{"given":"Heri","family":"Yanti","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Faculty of Mathematics and Natural Sciences, IPB University, Bogor 16680, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0138-4539","authenticated-orcid":false,"given":"Lik Tong","family":"Tan","sequence":"additional","affiliation":[{"name":"Natural Sciences and Science Education, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore 637616, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Nicole J.","family":"de Voogd","sequence":"additional","affiliation":[{"name":"Institute of Biology Leiden (IBL), Leiden University, 2300 RA Leiden, The Netherlands"},{"name":"Naturalis Biodiversity Center, 2333 BE Leiden, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anggia","family":"Murni","sequence":"additional","affiliation":[{"name":"Tropical Biopharmaca Research Center, IPB University, Bogor 16128, 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Am. Chem. Soc."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Tan, L.T., and Hanif, N. (2025). Chemical evolution of Indonesian marine natural products. Marine Natural Products Research in South-East Asia, Springer Nature.","DOI":"10.1007\/978-3-032-01098-8"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"964","DOI":"10.1039\/D2NP00082B","article-title":"Revisiting the manzamine biosynthetic hypothesis","volume":"40","author":"Piwko","year":"2023","journal-title":"Nat. Prod. Rep."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Waters, A.L., Peraud, O., Kasanah, N., Sims, J.W., Kothalawala, N., Anderson, M.A., Abbas, S.H., Rao, K.V., Jupally, V.R., and Kelly, M. (2014). An analysis of the sponge Acanthostrongylophora ingens microbiome yields an actinomycete that produces the natural product manzamine A. Front. Mar. Sci., 1.","DOI":"10.3389\/fmars.2014.00054"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"286","DOI":"10.1021\/acs.jnatprod.9b00577","article-title":"The marine natural product manzamine A inhibits cervical cancer by targeting the SIX1 protein","volume":"83","author":"Karan","year":"2020","journal-title":"J. Nat. Prod."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Tan, L.T., Widyantoro, C., and Hanif, N. (2026). Tides of promise: Sponge-derived marine natural products in Southeast Asia. Molecules, 31.","DOI":"10.3390\/molecules31050914"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"177295","DOI":"10.1016\/j.ejphar.2025.177295","article-title":"Manzamine A: A promising marine-derived cancer therapeutic for multi-targeted interactions with E2F8, SIX1, AR, GSK-3\u03b2, and V-ATPase\u2014A systematic review","volume":"990","author":"Mishan","year":"2025","journal-title":"Eur. J. Pharm."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Mayer, A.M.S., Hall, M.L., Lach, J., Canton, C., Kontoyianni, M., Choo, Y., Clifford, J., Chandrasena, K., Karan, D., and Hamann, M.T. (2021). RSK1 vs. RSK2 inhibitory activity of the marine \u03b2-carboline alkaloid manzamine a: A biochemical, cervical cancer protein expression, and computational study. Mar. Drugs., 19.","DOI":"10.3390\/md19090506"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"780","DOI":"10.1016\/j.copbio.2010.09.013","article-title":"The expanding role of marine microbes in pharmaceutical development","volume":"21","author":"Waters","year":"2010","journal-title":"Curr. Opin. Biotechnol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"2076","DOI":"10.1158\/0008-5472.CAN-04-3642","article-title":"Glycogen synthase kinase-3\u03b2 participates in nuclear factor \u03ba\u03b2-mediated gene transcription and cell survival in pancreatic cancer cells","volume":"65","author":"Ougolkov","year":"2005","journal-title":"Cancer Res."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Yadav, A.K., Vashishta, V., Joshi, N., and Taneja, P. (2014). AR-A 014418 used against GSK3beta downregulates expression of hnRNPA1 and SF2\/ASF splicing factors. J. Oncol., 695325.","DOI":"10.1155\/2014\/695325"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1397","DOI":"10.1021\/np060092r","article-title":"Glycogen synthase kinase-3 (GSK-3) inhibitory activity and structure\u2013activity relationship (SAR) studies of the manzamine alkaloids. potential for Alzheimer\u2019s disease","volume":"70","author":"Hamann","year":"2007","journal-title":"J. Nat. Prod."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Kn\u00f6lker, H.-J. (2020). The manzamine alkaloids. The Alkaloid, Elsevier. Chapter 1.","DOI":"10.1016\/bs.alkal.2020.03.001"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1761","DOI":"10.1038\/s41417-022-00489-8","article-title":"Circ-GSK3B up-regulates GSK3B to suppress the progression of lung adenocarcinoma","volume":"29","author":"Zhu","year":"2022","journal-title":"Cancer Gene Ther."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"476","DOI":"10.1039\/C8NP00053K","article-title":"Challenges in the configurational assignment of natural products. A case-selective perspective","volume":"36","author":"Menna","year":"2019","journal-title":"Nat. Prod. Rep."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Huo, Z.-Q., Zhu, F., Zhang, X.-W., Zhang, X., Liang, H.-B., Yao, J.-C., Liu, Z., Zhang, G.-M., Yao, Q.-Q., and Qin, G.-F. (2022). Approaches to configuration determination of flexible marine natural products: Advances and prospects. Mar. Drugs, 20.","DOI":"10.3390\/md20050333"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2299","DOI":"10.1021\/acs.jnatprod.9b00603","article-title":"Efficient protocol for accurately calculating 13C chemical shifts of conformationally flexible natural products: Scope, assessment, and limitations","volume":"82","author":"Hehre","year":"2019","journal-title":"J. Nat. Prod."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"3170","DOI":"10.1080\/14786419.2022.2147171","article-title":"Stereochemical determination of NMR chemical shifts in marine terpenoids, antheliol and sangiangol B using DFT calculations","volume":"37","author":"Hanif","year":"2023","journal-title":"Nat. Prod. Res."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Hanif, N., Tyas, T.A., Hidayati, L., Dinelsa, F.F., Provita, D., Kinnary, N.R., Prasetiawan, F.M., Khalik, G.A., Mubarok, Z., and Tohir, D. (2021). Oxy-polybrominated diphenyl ethers from the Indonesian marine sponge, Lamellodysidea herbacea: X-ray, SAR, and computational studies. Molecules, 26.","DOI":"10.3390\/molecules26216328"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"eadj9075","DOI":"10.1126\/sciadv.adj9075","article-title":"A bacterial spermidine biosynthetic pathway via carboxyaminopropylagmatine","volume":"9","author":"Xi","year":"2023","journal-title":"Sci. Adv."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"525","DOI":"10.1039\/D2NP00087C","article-title":"Polyamine-containing natural products: Structure, bioactivity, and biosynthesis","volume":"41","author":"Long","year":"2024","journal-title":"Nat. Prod. Rep."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"e202209651","DOI":"10.1002\/anie.202209651","article-title":"Total synthesis of the tetracyclic pyridinium alkaloid epi-tetradehydrohalicyclamine B","volume":"61","author":"Dalling","year":"2022","journal-title":"Angew. Chem. Int. Ed."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"2059","DOI":"10.1016\/0040-4039(92)88141-Q","article-title":"On the biosynthesis of manzamines","volume":"33","author":"Baldwin","year":"1992","journal-title":"Tetrahedron Lett."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"3154","DOI":"10.1002\/(SICI)1521-3765(19991105)5:11<3154::AID-CHEM3154>3.0.CO;2-7","article-title":"Studies on the biomimetic synthesis of the manzamine alkaloids","volume":"5","author":"Baldwin","year":"1999","journal-title":"Chem. Eur. J."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"823","DOI":"10.1021\/np020592u","article-title":"New manzamine alkaloids with the activity against infectious and tropical parasitic disease from an Indonesian sponge","volume":"66","author":"Rao","year":"2003","journal-title":"J. Nat. Prod."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"116560","DOI":"10.1016\/j.bmc.2021.116560","article-title":"Isolation and biological activity of azocine and azocane alkaloids","volume":"54","author":"Lee","year":"2022","journal-title":"Bioorg. Med. Chem."},{"key":"ref_27","first-page":"185","article-title":"Bioactive (+)-manzamine A and (+)-8-hydroxymanzamine A tertiary bases and salts from Acanthostrongylophora ingens and their preparations","volume":"4","author":"Samoylenko","year":"2009","journal-title":"Nat. Prod. Commun."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1575","DOI":"10.1021\/acs.jnatprod.7b00121","article-title":"Manzamine alkaloids from an Acanthostrongylophora sp. sponge","volume":"80","author":"Kim","year":"2017","journal-title":"J. Nat. Prod."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"22027","DOI":"10.1038\/s41598-024-72577-8","article-title":"Investigating the binding affinity, molecular dynamics, and ADMET properties of curcumin-IONPs as a mucoadhesive bioavailable oral treatment for iron deficiency anemia","volume":"14","author":"Alsedfy","year":"2024","journal-title":"Sci. Rep."},{"key":"ref_30","first-page":"381029","article-title":"Small-molecule inhibitors of GSK-3: Structural insights and their application to Alzheimer\u2032s disease models","volume":"32","author":"Kramer","year":"2012","journal-title":"Int. J. Alzheimer\u2019s Dis."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"571","DOI":"10.7150\/thno.14334","article-title":"Glycogen synthase kinase-3 (GSK-3)-targeted therapy and imaging","volume":"6","author":"Pandey","year":"2016","journal-title":"Theranostics"},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Sayas, C.L., and Avila, J. (2021). GSK-3 and tau: A key duet in Alzheimer\u2019s disease. Cells, 10.","DOI":"10.3390\/cells10040721"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"688","DOI":"10.34172\/apb.2023.071","article-title":"Role of GSK-3\u03b2 inhibitors: New promises and opportunities for Alzheimer\u2019s disease","volume":"13","author":"Shri","year":"2023","journal-title":"Adv. Pharm. Bull."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Hanif, N., Miftah, J.A., Yanti, H.D., Oluwabusola, E.T., Zahra, V.A., Salleh, N.F., Kundukad, B., Tan, L.T., de Voogd, N.J., and Rachmania, N. (2025). Integrated biological and chemical investigation of Indonesia marine organisms targeting anti-quorum sensing, anti-biofilm, and anti-biocorrosion activities. Molecules, 30.","DOI":"10.3390\/molecules30061202"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"5493","DOI":"10.1016\/S0040-4039(00)96762-5","article-title":"Manzamine B and C, two novel alkaloids from the sponge Halichlona sp","volume":"28","author":"Sakai","year":"1987","journal-title":"Tetrahedron Lett."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"339","DOI":"10.1107\/S0021889808042726","article-title":"OLEX2: A complete structure solution, refinement and analysis program","volume":"42","author":"Dolomanov","year":"2009","journal-title":"J. Appl. Crystallogr."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1107\/S2053273314026370","article-title":"SHELXT-integrated space-group and crystal-structure determination","volume":"A71","author":"Sheldrick","year":"2015","journal-title":"Found. Crystallogr."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1107\/S2053229614024218","article-title":"Crystal structure refinement with SHELXL","volume":"C71","author":"Sheldrick","year":"2015","journal-title":"Cryst. Struct. Commun."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"4668","DOI":"10.1080\/14786419.2025.2559778","article-title":"Integrated biological and chemical investigation of Papuan marine organisms for the discovery of potential cytotoxic marine natural products","volume":"40","author":"Hanif","year":"2026","journal-title":"Nat. Prod. Res."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"8","DOI":"10.3844\/ajptsp.2009.8.11","article-title":"Chaenomeles Sinensis: A potent \u03b1-and \u03b2-glucosidase inhibitor","volume":"4","author":"Sancheti","year":"2009","journal-title":"Am. J. Pharmacol. Toxicol."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"783","DOI":"10.1080\/1062936X.2015.1078407","article-title":"PASS Targets: Ligand-based multi-target computational system based on public data and na\u00efve Bayes approach","volume":"26","author":"Pogodin","year":"2015","journal-title":"SAR QSAR Environ. Res."}],"container-title":["Marine Drugs"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1660-3397\/24\/9\/313\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T09:28:38Z","timestamp":1788773318000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1660-3397\/24\/9\/313"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,7]]},"references-count":41,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2026,9]]}},"alternative-id":["md24090313"],"URL":"https:\/\/doi.org\/10.3390\/md24090313","relation":{},"ISSN":["1660-3397"],"issn-type":[{"value":"1660-3397","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,7]]}}}