{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T12:07:48Z","timestamp":1789992468234,"version":"4.0.1"},"reference-count":38,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T00:00:00Z","timestamp":1789948800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100007061","name":"Secretar\u00eda Nacional de Ciencia, Tecnolog\u00eda e Innovaci\u00f3n","doi-asserted-by":"publisher","award":["CIU-2025-017"],"award-info":[{"award-number":["CIU-2025-017"]}],"id":[{"id":"10.13039\/501100007061","id-type":"DOI","asserted-by":"publisher"}]},{"award":["CIU-2025-017"],"award-info":[{"award-number":["CIU-2025-017"]}],"id":[{"id":"https:\/\/ror.org\/03gat5t60","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>The accumulation of polyethylene (PE) in the environment represents a persistent ecological challenge, and the search for biological agents capable of degrading it without relying on prior abiotic pretreatment remains an active area of research. In this study, three bacterial strains\u2014Pseudomonas aeruginosa, Enterobacter hormaechei, and Acinetobacter pittii\u2014were isolated from the gut of Galleria mellonella larvae dietarily induced with native low-density polyethylene (LDPE), without prior UV, thermal, or chemical treatment. Molecular identification was confirmed by 16S rRNA gene sequencing and maximum-likelihood phylogenetic analysis. Degradative activity was assessed using a multi-method approach: a colorimetric DCPIP assay, gravimetric mass loss at 45 days, FTIR-ATR spectroscopy, SDS-PAGE, and scanning electron microscopy. All three strains showed metabolic activity toward LDPE, with A. pittii producing the greatest mass loss. FTIR analysis revealed the appearance of hydroxyl and C\u2013O-containing functionalities without detectable carbonyl accumulation, a pattern consistent with the hypothesized activation of an oxidative pathway mediated by the alkane hydroxylase (AlkB) system, pending direct molecular\/biochemical confirmation. These results expand the still-limited number of reports on native-PE-degrading activity documented individually for E. hormaechei and A. pittii and reinforce the value of the G. mellonella gut microbiome as a reservoir of bacteria with biotechnological potential for plastic waste management.<\/jats:p>","DOI":"10.3390\/polym18182309","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T11:05:53Z","timestamp":1789988753000},"page":"2309","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Native Polyethylene Biodegradation by Gut-Associated Bacteria from Galleria mellonella Larvae: Multi-Method Evidence Without Abiotic Pretreatment"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-0720-8678","authenticated-orcid":false,"given":"\u00d3scar","family":"Mart\u00ednez Gonz\u00e1lez","sequence":"first","affiliation":[{"name":"Department of Biology, 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Sci. Technol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1016\/j.ibiod.2013.12.014","article-title":"Microbial Degradation and Deterioration of Polyethylene\u2014A Review","volume":"88","author":"Bassi","year":"2014","journal-title":"Int. Biodeterior. Biodegrad."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"143736","DOI":"10.1016\/j.chemosphere.2024.143736","article-title":"Teabag-derived micro\/nanoplastics (true-to-life MNPLs) as a surrogate for real-life exposure scenarios","volume":"368","author":"Banaei","year":"2024","journal-title":"Chemosphere"},{"key":"ref_4","first-page":"145","article-title":"Biodegradation of Polyethylene by a Soil Bacterium and AlkB Cloned Recombinant Cell","volume":"3","author":"Yoon","year":"2012","journal-title":"J. Bioremediat. Biodegrad."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"13776","DOI":"10.1021\/es504038a","article-title":"Evidence of Polyethylene Biodegradation by Bacterial Strains from the Guts of Plastic-Eating Waxworms","volume":"48","author":"Yang","year":"2014","journal-title":"Environ. Sci. Technol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"136822","DOI":"10.1016\/j.jhazmat.2024.136822","article-title":"Enhanced Biodegradation of High-Density Polyethylene Microplastics: Study of Bacterial Efficiency and Process Parameters","volume":"485","author":"Newrick","year":"2025","journal-title":"J. Hazard. Mater."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"18509","DOI":"10.1007\/s11356-019-05038-9","article-title":"Efficient Biodegradation of Polyethylene (HDPE) Waste by the Plastic-Eating Lesser Waxmoth (Achroia grisella)","volume":"26","author":"Kundungal","year":"2019","journal-title":"Environ. Sci. Pollut. Res."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"19","DOI":"10.33333\/rp.vol56n2.02","article-title":"Oxidaci\u00f3n de Polietileno de Baja Densidad, Polies-tireno Expandido y Pl\u00e1sticos Oxo-Biodegradables por Galleria mellonella","volume":"56","author":"Jaramillo","year":"2025","journal-title":"Rev. Polit\u00e9c."},{"key":"ref_9","unstructured":"MacFaddin, J.F. (2000). Biochemical Tests for Identification of Medical Bacteria, Lippincott Williams & Wilkins. [3rd ed.]."},{"key":"ref_10","unstructured":"Koneman, E.W., Allen, S., Janda, W., Procop, G., Schreckenberger, P., and Woods, G. (2006). Color Atlas and Textbook of Diagnostic Microbiology, Lippincott Williams & Wilkins. [6th ed.]."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"13","DOI":"10.54987\/bstr.v5i2.358","article-title":"Screening of Hydrocarbon-degrading Bacterial Isolates Using the Redox Application of 2,6-DCPIP","volume":"5","author":"Habib","year":"2017","journal-title":"Bioremediation Sci. Technol. Res."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Campanale, C., Savino, I., Massarelli, C., and Uricchio, V.F. (2023). Fourier Transform Infrared Spectroscopy to Assess the Degree of Alteration of Artificially Aged and Environmentally Weathered Microplastics. Polymers, 15.","DOI":"10.3390\/polym15040911"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"2681","DOI":"10.1080\/10643389.2020.1807450","article-title":"Contributions of Fourier Transform Infrared Spectroscopy in Microplastic Pollution Research: A Review","volume":"51","author":"Veerasingam","year":"2021","journal-title":"Crit. Rev. Environ. Sci. Technol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"141","DOI":"10.1016\/j.ibiod.2015.04.024","article-title":"Functional analysis of alkane hydroxylase system derived from Pseudomonas aeruginosa E7 for low molecular weight polyethylene biodegradation","volume":"103","author":"Jeon","year":"2015","journal-title":"Int. Biodeterior. Biodegrad."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"e15731","DOI":"10.1016\/j.heliyon.2023.e15731","article-title":"Isolation of a polyethylene-degrading bacterium, Acinetobacter guillouiae, using a novel screening method based on a redox indicator","volume":"9","author":"Kim","year":"2023","journal-title":"Heliyon"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Ren, L., Men, L., Zhang, Z., Guan, F., Tian, J., Wang, B., Wang, J., Zhang, Y., and Zhang, W. (2019). Biodegradation of Polyethylene by Enterobacter sp. D1 from the Guts of Wax Moth Galleria mellonella. Int. J. Environ. Res. Public Health, 16.","DOI":"10.3390\/ijerph16111941"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"118074","DOI":"10.1016\/j.ecoenv.2025.118074","article-title":"Low and high-density polyethylene and expanded polystyrene biodegradation by the greater wax moth Galleria mellonella L. reveals a key role of the gut microbiome","volume":"294","author":"Kehkashan","year":"2025","journal-title":"Ecotoxicol. Environ. Saf."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"224","DOI":"10.1139\/cjm-2018-0335","article-title":"Microbial degradation of low-density polyethylene and synthesis of polyhy-droxyalkanoate polymers","volume":"65","author":"Montazer","year":"2019","journal-title":"Can. J. Microbiol."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Montazer, Z., Mohanan, N., Sharma, P.K., and Levin, D.B. (2020). Microbial and Enzymatic Degradation of Synthetic Plastics. Front. Microbiol., 11.","DOI":"10.3389\/fmicb.2020.580709"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"167708","DOI":"10.1016\/j.scitotenv.2023.167708","article-title":"Exploitation of Enterobacter hormaechei for biodegradation of multiple plastics","volume":"907","author":"Sun","year":"2024","journal-title":"Sci. Total Environ."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1016\/0923-2508(89)90046-6","article-title":"Purification and peptidase activity of a bacte-riolytic extracellular enzyme from Pseudomonas aeruginosa","volume":"140","author":"Brito","year":"1989","journal-title":"Res. Microbiol."},{"key":"ref_22","first-page":"92","article-title":"Isolation and Identification of a Novel, Lipase-Producing Bacterium, Pseudomonas aeruginosa KM110","volume":"3","year":"2011","journal-title":"Iran. J. Microbiol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1186\/s44316-024-00011-0","article-title":"Recent trends in microbial and enzymatic plastic degradation: A solution for plastic pollution predicaments","volume":"1","author":"Dhali","year":"2024","journal-title":"Biotechnol. Sustain. Mater."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"107991","DOI":"10.1016\/j.biotechadv.2022.107991","article-title":"Biodegradation of polyethylene and polystyrene: From microbial deterioration to enzyme discovery","volume":"60","author":"Zhang","year":"2022","journal-title":"Biotechnol. Adv."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"115180","DOI":"10.1016\/j.wasman.2025.115180","article-title":"Potential role of Galleria mellonella larval microbiota in polyethylene biodegradation","volume":"209","author":"Pivato","year":"2026","journal-title":"Waste Manag."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1495","DOI":"10.1016\/j.polymdegradstab.2005.10.007","article-title":"Acquired Biodegradability of Polyethylenes Con-taining Pro-Oxidant Additives","volume":"91","author":"Koutny","year":"2006","journal-title":"Polym. Degrad. Stab."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"e01151-20","DOI":"10.1128\/mSphere.01151-20","article-title":"Environmental Con-sortium Containing Pseudomonas and Bacillus Species Synergistically Degrades Polyethylene Terephthalate Plastic","volume":"5","author":"Roberts","year":"2020","journal-title":"mSphere"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Mattelin, V., Verfaille, L., Kundu, K., De Wildeman, S., and Boon, N. (2023). A New Colorimetric Test for Accurate Determination of Plastic Biodegradation. Polymers, 15.","DOI":"10.3390\/polym15102311"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"5568","DOI":"10.1038\/s41467-022-33127-w","article-title":"Wax Worm Saliva and the Enzymes Therein Are the Key to Polyethylene Degradation","volume":"13","author":"Castroviejo","year":"2022","journal-title":"Nat. Commun."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"129656","DOI":"10.1016\/j.jhazmat.2022.129656","article-title":"Characteristics and polyethylene biodegradation function of a novel cold-adapted bacterial laccase from Psychrobacter sp. NJ228","volume":"439","author":"Zhang","year":"2022","journal-title":"J. Hazard. Mater."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Zhang, Y., Lin, Y., Gou, H., Feng, X., Zhang, X., and Yang, L. (2022). Screening of polyethylene-degrading bacteria from Rhyzopertha dominica and evaluation of its key enzymes degrading polyethylene. Polymers, 14.","DOI":"10.3390\/polym14235127"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"e70005","DOI":"10.1002\/aic.70005","article-title":"Discovery of a polyethylene biodegradable laccase from Acinetobacter dijkshoorniae","volume":"71","author":"Wu","year":"2025","journal-title":"AIChE J."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"102206","DOI":"10.1016\/j.bcab.2021.102206","article-title":"Enterobacter sp. AI1 Produced a Thermo-Acidic-Tolerant Laccase with a High Potential for Textile Dyes Degradation","volume":"38","author":"Chiedu","year":"2021","journal-title":"Biocatal. Agric. Biotechnol."},{"key":"ref_34","first-page":"789","article-title":"Enterobacter cloacae-mediated polymer biodegradation: In-silico analysis predicts broad spectrum degradation potential by alkane monooxygenase","volume":"35","author":"Shafana","year":"2024","journal-title":"Biodegradation"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"117628","DOI":"10.1016\/j.lwt.2025.117628","article-title":"Multiplex qPCR for Simultaneous Quantification of the Main Psychrotrophic Bacteria and Their Enzymes in Raw Milk","volume":"222","author":"Wu","year":"2025","journal-title":"LWT-Food Sci. Technol."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Magalh\u00e3es, S., Alves, L., Romano, A., Medronho, B., and Rasteiro, M.G. (2022). Extraction and Characterization of Microplastics from Portuguese Industrial Effluents. Polymers, 14.","DOI":"10.3390\/polym14142902"},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Castelvetro, V., Corti, A., La Nasa, J., Modugno, F., Ceccarini, A., Giannarelli, S., Vinciguerra, V., and Bertoldo, M. (2021). Polymer Identification and Specific Analysis (PISA) of Microplastic Total Mass in Sediments of the Protected Marine Area of the Meloria Shoals. Polymers, 13.","DOI":"10.20944\/preprints202102.0211.v1"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Anuar, S.T., Altarawnah, R.S., Mohd Ali, A.A., Lee, B.Q., Khalik, W.M.A.W.M., Yusof, K.M.K.K., and Ibrahim, Y.S. (2022). Utilizing Pyrolysis\u2013Gas Chromatography\/Mass Spectrometry for Monitoring and Analytical Characterization of Microplastics in Polychaete Worms. Polymers, 14.","DOI":"10.3390\/polym14153054"}],"container-title":["Polymers"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4360\/18\/18\/2309\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T11:17:15Z","timestamp":1789989435000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4360\/18\/18\/2309"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,21]]},"references-count":38,"journal-issue":{"issue":"18","published-online":{"date-parts":[[2026,9]]}},"alternative-id":["polym18182309"],"URL":"https:\/\/doi.org\/10.3390\/polym18182309","relation":{},"ISSN":["2073-4360"],"issn-type":[{"value":"2073-4360","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,21]]}}}