{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T19:51:37Z","timestamp":1789069897560,"version":"build-2803163510"},"reference-count":56,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2025,8,23]],"date-time":"2025-08-23T00:00:00Z","timestamp":1755907200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Science Centre, Poland","award":["2017\/26\/D\/NZ6\/00136"],"award-info":[{"award-number":["2017\/26\/D\/NZ6\/00136"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Current diagnostic methods for bacterial infections in critically ill patients, including ventilator-associated pneumonia (VAP), are time-consuming, while empirical antibiotic therapy contributes to rising resistance. Bacteria-derived volatile organic compounds (VOCs) are being explored as specific biomarkers for pathogen identification and treatment monitoring. This study expands knowledge of Escherichia coli metabolism by identifying VOCs produced by both multidrug-resistant and susceptible strains, characterizing their temporal profiles during growth, and assessing VOC profile changes after imipenem exposure. Reference strains and 21 clinical isolates (derived from BAL samples of VAP patients) were cultured under controlled conditions. Headspace VOCs were preconcentrated using multibed sorption tubes and analyzed by gas chromatography\u2013mass spectrometry (GC-MS), with compound identities confirmed using external standards. Sampling at seven time points over 24 h cultures revealed three VOC emission patterns: continuous release, temporary maximum, and compound uptake. In total, 57 VOCs were identified from the susceptible strain and 41 from the resistant one, with dimethyl disulfide, 2-butenal, ethyl acetate, and furan elevated in the resistant strain. Imipenem addition altered VOC production in the susceptible strain, with levels of six compounds elevated and seven reduced, while resistant profiles remained stable. Clinical isolates produced 71 VOCs, showing greater metabolic diversity and highlighting the relevance of isolate-derived VOCs in future studies.<\/jats:p>","DOI":"10.3390\/ijms26178191","type":"journal-article","created":{"date-parts":[[2025,8,25]],"date-time":"2025-08-25T00:10:36Z","timestamp":1756080636000},"page":"8191","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Profiling of Volatile Metabolites of Escherichia coli Using Gas Chromatography\u2013Mass Spectrometry"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9918-4708","authenticated-orcid":false,"given":"Karolina","family":"\u017buchowska","sequence":"first","affiliation":[{"name":"Department of Pharmacodynamics and Molecular Pharmacology, Faculty of Pharmacy, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toru\u0144, A. Jurasza 2 Str., 85-089 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alicja","family":"Tracewska","sequence":"additional","affiliation":[{"name":"Department of Pharmacodynamics and Molecular Pharmacology, Faculty of Pharmacy, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toru\u0144, A. Jurasza 2 Str., 85-089 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2387-9778","authenticated-orcid":false,"given":"Dagmara","family":"Depka-Radzikowska","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Faculty of Pharmacy, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toru\u0144, Maria Curie-Sk\u0142odowska 9 Str., 85-094 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6787-1378","authenticated-orcid":false,"given":"Tomasz","family":"Bogiel","sequence":"additional","affiliation":[{"name":"Department of Propaedeutics of Medicine and Infection Prevention, Faculty of Pharmacy, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toru\u0144, 9 Maria Curie-Sk\u0142odowska Str., 85-094 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-3633-3014","authenticated-orcid":false,"given":"Robert","family":"W\u0142odarski","sequence":"additional","affiliation":[{"name":"Department of Anaesthesiology and Intensive Care, 10th Military Research Hospital and Polyclinic, Powsta\u0144c\u00f3w Warszawy 5 Str., 85-681 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3971-9816","authenticated-orcid":false,"given":"Barbara","family":"Bojko","sequence":"additional","affiliation":[{"name":"Department of Pharmacodynamics and Molecular Pharmacology, Faculty of Pharmacy, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toru\u0144, A. Jurasza 2 Str., 85-089 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8696-0816","authenticated-orcid":false,"given":"Wojciech","family":"Filipiak","sequence":"additional","affiliation":[{"name":"Department of Pharmacodynamics and Molecular Pharmacology, Faculty of Pharmacy, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toru\u0144, A. Jurasza 2 Str., 85-089 Bydgoszcz, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,23]]},"reference":[{"key":"ref_1","unstructured":"European Centre for Disease Prevention and Control (2024). Antimicrobial Resistance in the EU\/EEA (EARS-Net)\u2014Annual Epidemiological Report 2023."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Elmassry, M.M., and Piechulla, B. (2020). Volatilomes of Bacterial Infections in Humans. Front. Neurosci., 14.","DOI":"10.3389\/fnins.2020.00257"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"027106","DOI":"10.1088\/1752-7155\/8\/2\/027106","article-title":"Identification of Microorganisms Based on Headspace Analysis of Volatile Organic Compounds by Gas Chromatography-Mass Spectrometry","volume":"8","author":"Boots","year":"2014","journal-title":"J. Breath Res."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"228","DOI":"10.1002\/jobm.201600505","article-title":"Characteristics of Volatile Organic Compounds Produced from Five Pathogenic Bacteria by Headspace-Solid Phase Micro-Extraction\/Gas Chromatography-Mass Spectrometry","volume":"57","author":"Chen","year":"2017","journal-title":"J. Basic Microbiol."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Hewett, K., Drabi\u0144ska, N., White, P., Avison, M.B., Persad, R., Ratcliffe, N., and Costello, B.d.L. (2020). Towards the Identification of Antibiotic-Resistant Bacteria Causing Urinary Tract Infections Using Volatile Organic Compounds Analysis\u2014A Pilot Study. Antibiotics, 9.","DOI":"10.3390\/antibiotics9110797"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2603","DOI":"10.1007\/s00253-012-3924-4","article-title":"Ion Mobility Spectrometry for Microbial Volatile Organic Compounds: A New Identification Tool for Human Pathogenic Bacteria","volume":"93","author":"Vautz","year":"2012","journal-title":"Appl. Microbiol. Biotechnol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1415","DOI":"10.12688\/f1000research.12003.2","article-title":"Diagnosis of Three Different Pathogenic Microorganisms by Gas Chromatography-Mass Spectrometry","volume":"6","author":"Karami","year":"2017","journal-title":"F1000Research"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Fitzgerald, S., Holland, L., and Morrin, A. (2021). An Investigation of Stability and Species and Strain-Level Specificity in Bacterial Volatilomes. Front. Microbiol., 12.","DOI":"10.3389\/fmicb.2021.693075"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"6617","DOI":"10.1007\/s00216-014-8111-2","article-title":"Investigation of Volatile Metabolites during Growth of Escherichia coli and Pseudomonas aeruginosa by Needle Trap-GC-MS","volume":"406","author":"Zscheppank","year":"2014","journal-title":"Anal. Bioanal. Chem."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"363","DOI":"10.1093\/chromsci\/bmt042","article-title":"Identification of Volatile Organic Compounds Produced by Bacteria Using HS-SPME-GC-MS","volume":"52","author":"Tait","year":"2014","journal-title":"J. Chromatogr. Sci."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2179","DOI":"10.1128\/AEM.02069-07","article-title":"On-Line Monitoring of Microbial Volatile Metabolites by Proton Transfer Reaction-Mass Spectrometry","volume":"74","author":"Bunge","year":"2008","journal-title":"Appl. Environ. Microbiol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"628","DOI":"10.1016\/j.mimet.2005.09.016","article-title":"The Rapid Evaluation of Bacterial Growth in Blood Cultures by Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS) and Comparison with the BacT\/ALERT Automated Blood Culture System","volume":"65","author":"Scotter","year":"2006","journal-title":"J. Microbiol. Methods"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"3665","DOI":"10.1007\/s00253-013-4762-8","article-title":"Detection and Validation of Volatile Metabolic Patterns over Different Strains of Two Human Pathogenic Bacteria during Their Growth in a Complex Medium Using Multi-Capillary Column-Ion Mobility Spectrometry (MCC-IMS)","volume":"97","author":"Kunze","year":"2013","journal-title":"Appl. Microbiol. Biotechnol."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Fitzgerald, S., Duffy, E., Holland, L., and Morrin, A. (2020). Multi-Strain Volatile Profiling of Pathogenic and Commensal Cutaneous Bacteria. Sci. Rep., 10.","DOI":"10.1038\/s41598-020-74909-w"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1016\/j.mimet.2010.12.001","article-title":"Multivariate Analysis of Bacterial Volatile Compound Profiles for Discrimination between Selected Species and Strains in Vitro","volume":"84","author":"Thorn","year":"2011","journal-title":"J. Microbiol. Methods"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1016\/j.diagmicrobio.2006.01.031","article-title":"The Rapid Evaluation of Bacterial Growth and Antibiotic Susceptibility in Blood Cultures by Selected Ion Flow Tube Mass Spectrometry","volume":"55","author":"Allardyce","year":"2006","journal-title":"Diagn. Microbiol. Infect. Dis."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1059","DOI":"10.1093\/cid\/ciac859","article-title":"Microbial Volatiles as Diagnostic Biomarkers of Bacterial Lung Infection in Mechanically Ventilated Patients","volume":"76","author":"Ahmed","year":"2023","journal-title":"Clin. Infect. Dis."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1097","DOI":"10.1111\/j.1365-2672.2012.05414.x","article-title":"Volatile Compound Profiling for the Identification of Gram-Negative Bacteria by Ion-Molecule Reaction-Mass Spectrometry","volume":"113","author":"Dolch","year":"2012","journal-title":"J. Appl. Microbiol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"4426","DOI":"10.1128\/JCM.00392-10","article-title":"Fast Detection of Volatile Organic Compounds from Bacterial Cultures by Secondary Electrospray Ionization-Mass Spectrometry","volume":"48","author":"Zhu","year":"2010","journal-title":"J. Clin. Microbiol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"100898","DOI":"10.1016\/j.jpha.2023.11.005","article-title":"Modern Approaches for Detection of Volatile Organic Compounds in Metabolic Studies Focusing on Pathogenic Bacteria: Current State of the Art","volume":"14","author":"Filipiak","year":"2024","journal-title":"J. Pharm. Anal."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1186\/2001-1326-2-13","article-title":"Gas Signatures from Escherichia coli and Escherichia coli-inoculated Human Whole Blood","volume":"2","author":"Umber","year":"2013","journal-title":"Clin. Transl. Med."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.advms.2021.09.001","article-title":"Application of a Solid-Phase Microextraction-Gas Chromatography-Mass Spectrometry\/Metal Oxide Sensor System for Detection of Antibiotic Susceptibility in Urinary Tract Infection-Causing Escherichia coli\u2014A Proof of Principle Study","volume":"67","author":"Hewett","year":"2022","journal-title":"Adv. Med. Sci."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"59","DOI":"10.1016\/j.jpba.2019.01.044","article-title":"Sniffing out Resistance\u2014Rapid Identification of Urinary Tract Infection-Causing Bacteria and Their Antibiotic Susceptibility Using Volatile Metabolite Profiles","volume":"167","author":"Smart","year":"2019","journal-title":"J. Pharm. Biomed. Anal."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1186\/s13568-022-01367-0","article-title":"Use of GC-IMS for Detection of Volatile Organic Compounds to Identify Mixed Bacterial Culture Medium","volume":"12","author":"Lu","year":"2022","journal-title":"AMB Express"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"25316","DOI":"10.1039\/D4RA03601H","article-title":"Analysis and Application of Volatile Metabolic Profiles of Escherichia coli: A Preliminary GC-IMS-Based Study","volume":"14","author":"Zheng","year":"2024","journal-title":"RSC Adv."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"9091","DOI":"10.1007\/s00253-019-10181-x","article-title":"GC-IMS Headspace Analyses Allow Early Recognition of Bacterial Growth and Rapid Pathogen Differentiation in Standard Blood Cultures","volume":"103","author":"Drees","year":"2019","journal-title":"Appl. Microbiol. Biotechnol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"026001","DOI":"10.1088\/1752-7163\/aa8f7f","article-title":"Comprehensive Volatile Metabolic Fingerprinting of Bacterial and Fungal Pathogen Groups","volume":"12","author":"Rees","year":"2018","journal-title":"J. Breath Res."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Filipiak, W., W\u0142odarski, R., \u017buchowska, K., Tracewska, A., Winiarek, M., Daszkiewicz, D., Marsza\u0142ek, M., Depka, D., and Bogiel, T. (2024). Analysis of Bacterial Metabolites in Breath Gas of Critically III Patients for Diagnosis of Ventilator-Associated Pneumonia\u2014A Proof of Concept Study. Biomolecules, 14.","DOI":"10.20944\/preprints202410.1676.v1"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"712","DOI":"10.1111\/anae.15999","article-title":"Analysis of Exhaled Breath to Identify Critically III Patients with Ventilator-Associated Pneumonia","volume":"78","author":"Felton","year":"2023","journal-title":"Anaesthesia"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"124069","DOI":"10.1016\/j.talanta.2022.124069","article-title":"Rapid Screen for Ventilator Associated Pneumonia Using Exhaled Volatile Organic Compounds","volume":"253","author":"Xu","year":"2023","journal-title":"Talanta"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"13952","DOI":"10.1039\/C4RA16502K","article-title":"Rapid Recognition of Bacteremia in Humans Using Atmospheric Pressure Chemical Ionization Mass Spectrometry of Volatiles Emitted by Blood Cultures","volume":"5","author":"Chingin","year":"2015","journal-title":"RSC Adv."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"7155772","DOI":"10.1155\/2021\/7155772","article-title":"The Metabolome of Carbapenem-Resistant Klebsiella pneumoniae Infection in Plasma","volume":"2021","author":"Wen","year":"2021","journal-title":"Dis. Markers"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1186\/1465-9921-13-87","article-title":"Detection of Pseudomonas aeruginosa in Sputum Headspace through Volatile Organic Compound Analysis","volume":"13","author":"Goeminne","year":"2012","journal-title":"Respir. Res."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"016005","DOI":"10.1088\/1752-7163\/aae80e","article-title":"Exhaled human breath analysis in active pulmonary tuberculosis diagnostics by comprehensive gas chromatography-mass spectrometry and chemometric techniques","volume":"13","author":"Beccaria","year":"2019","journal-title":"J. Breath Res."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"610","DOI":"10.1111\/j.1472-765X.2011.03049.x","article-title":"Volatile Biomarkers of Pseudomonas aeruginosa in Cystic Fibrosis and Noncystic Fibrosis Bronchiectasis","volume":"52","author":"Savelev","year":"2011","journal-title":"Lett. Appl. Microbiol."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Filipiak, W., Wenzel, M., Ager, C., Mayhew, C.A., Bogiel, T., W\u0142odarski, R., and Nagl, M. (2024). Molecular Analysis of Volatile Metabolites Synthesized by Candida albicans and Staphylococcus aureus in In Vitro Cultures and Bronchoalveolar Lavage Specimens Reflecting Single- or Duo-Factor Pneumonia. Biomolecules, 14.","DOI":"10.20944\/preprints202404.1033.v1"},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Nasir, M., Bean, H.D., Smolinska, A., Rees, C.A., Zemanick, E.T., and Hill, J.E. (2018). Volatile Molecules from Bronchoalveolar Lavage Fluid Can \u201crule-in\u201d Pseudomonas aeruginosa and \u201cRule-out\u201d Staphylococcus aureus Infections in Cystic Fibrosis Patients. Sci. Rep., 8.","DOI":"10.1038\/s41598-017-18491-8"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"100242","DOI":"10.1016\/j.greeac.2025.100242","article-title":"Protocol for the Untargeted Analysis of Volatile Metabolites in the Headspace of Biological Samples Using Thin-Film Microextraction Coupled to GC\u2013MS","volume":"13","author":"Filipiak","year":"2025","journal-title":"Green Anal. Chem."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"e114279","DOI":"10.1371\/journal.pone.0114279","article-title":"Rapid and Accurate Detection of Urinary Pathogens by Mobile IMS-Based Electronic Nose: A Proof-of-Principle Study","volume":"9","author":"Roine","year":"2014","journal-title":"PLoS ONE"},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Bos, L.D.J., Sterk, P.J., and Schultz, M.J. (2013). Volatile Metabolites of Pathogens: A Systematic Review. PLoS Pathog., 9.","DOI":"10.1371\/journal.ppat.1003311"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"016004","DOI":"10.1088\/1752-7155\/9\/1\/016004","article-title":"Breath Analysis for in Vivo Detection of Pathogens Related to Ventilator-Associated Pneumonia in Intensive Care Patients: A Prospective Pilot Study","volume":"9","author":"Filipiak","year":"2015","journal-title":"J. Breath Res."},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Rees, C.A., Nasir, M., Smolinska, A., Lewis, A.E., Kane, K.R., Kossmann, S.E., Sezer, O., Zucchi, P.C., Doi, Y., and Hirsch, E.B. (2018). Detection of High-Risk Carbapenem-Resistant Klebsiella pneumoniae and Enterobacter cloacae Isolates Using Volatile Molecular Profiles. Sci. Rep., 8.","DOI":"10.1038\/s41598-018-31543-x"},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Filipiak, W., \u017buchowska, K., Marsza\u0142ek, M., Depka, D., Bogiel, T., Warmuzi\u0144ska, N., and Bojko, B. (2022). GC-MS Profiling of Volatile Metabolites Produced by Klebsiella pneumoniae. Front. Mol. Biosci., 9.","DOI":"10.3389\/fmolb.2022.1019290"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"027101","DOI":"10.1088\/1752-7155\/10\/2\/027101","article-title":"The Volatile Metabolome of Klebsiella pneumoniae in Human Blood","volume":"10","author":"Rees","year":"2016","journal-title":"J. Breath Res."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1007\/s11306-016-1161-z","article-title":"Volatile Metabolic Diversity of Klebsiella pneumoniae in Nutrient-Replete Conditions","volume":"13","author":"Rees","year":"2017","journal-title":"Metabolomics"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"4133","DOI":"10.1002\/jssc.201800684","article-title":"Profiling of Headspace Volatiles from Escherichia coli Cultures Using Silicone-Based Sorptive Media and Thermal Desorption GC\u2013MS","volume":"41","author":"Devaraj","year":"2018","journal-title":"J. Sep. Sci."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"112","DOI":"10.14715\/cmb\/2017.63.2.18","article-title":"Identification of Bacteria Using Volatile Organic Compounds","volume":"63","author":"Karami","year":"2017","journal-title":"Cell Mol. Biol."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"701","DOI":"10.1111\/j.1365-2672.2012.05370.x","article-title":"Variability in the Concentrations of Volatile Metabolites Emitted by Genotypically Different Strains of Pseudomonas aeruginosa","volume":"113","author":"Shestivska","year":"2012","journal-title":"J. Appl. Microbiol."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"426","DOI":"10.1111\/j.1574-6976.2009.00204.x","article-title":"Indole as an Intercellular Signal in Microbial Communities","volume":"34","author":"Lee","year":"2010","journal-title":"FEMS Microbiol. Rev."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"97","DOI":"10.1007\/BF00294190","article-title":"Bacteria Produce the Volatile Hydrocarbon Isoprene","volume":"30","author":"Kuzma","year":"1995","journal-title":"Curr. Microbiol."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"1011","DOI":"10.1515\/CCLM.2008.181","article-title":"Breath Isoprene\u2014Aspects of Normal Physiology Related to Age, Gender and Cholesterol Profile as Determined in a Proton Transfer Reaction Mass Spectrometry Study","volume":"46","author":"Kushch","year":"2008","journal-title":"Clin. Chem. Lab. Med."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"855","DOI":"10.1080\/10473289.2004.10470953","article-title":"Occurrence and Abatement of Volatile Sulfur Compounds during Biogas Production","volume":"54","author":"Andersson","year":"2004","journal-title":"J. Air Waste Manag. Assoc."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1016\/j.ymben.2017.07.003","article-title":"Isobutanol and 2-Ketoisovalerate Production by Klebsiella pneumoniae via a Native Pathway","volume":"43","author":"Gu","year":"2017","journal-title":"Metab. Eng."},{"key":"ref_54","doi-asserted-by":"crossref","unstructured":"Capelo-Martinez, J.L., and Igrejas, G. (2020). Beta-Lactams. Antibiotic Drug Resistance, John Wiley & Sons, Inc.","DOI":"10.1002\/9781119282549"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"3044","DOI":"10.1099\/mic.0.062687-0","article-title":"Characterization of Volatile Metabolites Taken up by or Released from Streptococcus pneumoniae and Haemophilus influenzae by Using GC-MS","volume":"158","author":"Filipiak","year":"2012","journal-title":"Microbiology"},{"key":"ref_56","unstructured":"(2025, May 31). MetaboAnalyst 6.0. Available online: https:\/\/www.metaboanalyst.ca."}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/26\/17\/8191\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T18:34:39Z","timestamp":1760034879000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/26\/17\/8191"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,8,23]]},"references-count":56,"journal-issue":{"issue":"17","published-online":{"date-parts":[[2025,9]]}},"alternative-id":["ijms26178191"],"URL":"https:\/\/doi.org\/10.3390\/ijms26178191","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,8,23]]}}}