Publications by authors named "Fernanda Monedeiro"

15 Publications

  • Page 1 of 1

Metabolic Profiling of VOCs Emitted by Bacteria Isolated from Pressure Ulcers and Treated with Different Concentrations of Bio-AgNPs.

Int J Mol Sci 2021 Apr 29;22(9). Epub 2021 Apr 29.

Interdisciplinary Centre of Modern Technologies, Nicolaus Copernicus University in Toruń, 4 Wileńska St., 87-100 Toruń, Poland.

Considering the advent of antibiotic resistance, the study of bacterial metabolic behavior stimulated by novel antimicrobial agents becomes a relevant tool to elucidate involved adaptive pathways. Profiling of volatile metabolites was performed to monitor alterations of bacterial metabolism induced by biosynthesized silver nanoparticles (bio-AgNPs). , , and were isolated from pressure ulcers, and their cultures were prepared in the presence/absence of bio-AgNPs at 12.5, 25 and 50 µg mL. Headspace solid phase microextraction associated to gas chromatography-mass spectrometry was the employed analytical platform. At the lower concentration level, the agent promoted positive modulation of products of fermentation routes and bioactive volatiles, indicating an attempt of bacteria to adapt to an ongoing suppression of cellular respiration. Augmented response of aldehydes and other possible products of lipid oxidative cleavage was noticed for increasing levels of bio-AgNPs. The greatest concentration of agent caused a reduction of 44 to 80% in the variety of compounds found in the control samples. Pathway analysis indicated overall inhibition of amino acids and fatty acids routes. The present assessment may provide a deeper understanding of molecular mechanisms of bio-AgNPs and how the metabolic response of bacteria is untangled.
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http://dx.doi.org/10.3390/ijms22094696DOI Listing
April 2021

Lipidomics as a Diagnostic Tool for Prostate Cancer.

Cancers (Basel) 2021 Apr 21;13(9). Epub 2021 Apr 21.

Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University, 87-100 Toruń, Poland.

The main goal of this study was to explore the phospholipid alterations associated with the development of prostate cancer (PCa) using two imaging methods: matrix-assisted laser desorption ionization with time-of-flight mass spectrometer (MALDI-TOF/MS), and electrospray ionization with triple quadrupole mass spectrometer (ESI-QqQ/MS). For this purpose, samples of PCa tissue ( = 40) were evaluated in comparison to the controls ( = 40). As a result, few classes of compounds, namely phosphatidylcholines (PCs), lysophosphatidylcholines (LPCs), sphingomyelins (SMs), and phosphatidylethanolamines (PEs), were determined. The obtained results were evaluated by univariate (Mann-Whitney U-test) and multivariate statistical analysis (principal component analysis, correlation analysis, volcano plot, artificial neural network, and random forest algorithm), in order to select the most discriminative features and to search for the relationships between the responses of these groups of substances, also in terms of the used analytical technique. Based on previous literature and our results, it can be assumed that PCa is linked with both the synthesis of fatty acids and lipid oxidation. Among the compounds, phospholipids, namely PC 16:0/16:1, PC 16:0/18:2, PC 18:0/22:5, PC 18:1/18:2, PC 18:1/20:0, PC 18:1/20:4, and SM d18:1/24:0, were assigned as metabolites with the best discriminative power for the tested groups. Based on the results, lipidomics can be found as alternative diagnostic tool for CaP diagnosis.
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http://dx.doi.org/10.3390/cancers13092000DOI Listing
April 2021

Cigarette smoke exposure causes systemic and autonomic cardiocirculatory changes in rats depending on the daily exposure dose.

Life Sci 2021 Apr 20;277:119498. Epub 2021 Apr 20.

Medical School, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil. Electronic address:

Aims: To evaluate the systemic changes and autonomic cardiocirculatory control of awaken rats chronically exposed to the cigarette smoke (CS) of 1 or 2 cigarettes/day.

Main Methods: Rats were exposed to clean air (control) or cigarette smoke of 1 (CS1) or 2 (CS2) cigarettes/animal/day for 30 days. Then, arterial pressure (AP) and heart rate (HR) were recorded in conscious rats to assess spontaneous baroreflex sensitivity and HR and AP variabilities. Evoked baroreflex and cardiac autonomic tone were evaluated by vasoactive drugs and autonomic blockers, respectively. In another group, ventilatory and cardiovascular parameters were recorded under hypoxia and hypercapnia stimulus. At the end of protocols, heart, lung, kidneys and liver were collected for histological analysis.

Key Findings: Rats exposed to CS showed morphological changes, being more evident in the CS2 group. Also, less weight gain and cardiac hypertrophy were prominent in CS2 rats. Basal AP and HR, spontaneous baroreflex sensitivity and cardiovascular variabilities were similar among groups. CS exposure progressively blunted the bradycardia response to phenylephrine (-2.2 ± 0.1 vs. -1.7 ± 0.2 vs. -1.5 ± 0.2) while the tachycardia response to sodium nitroprusside was slightly increased compared to control. Vagal tone was not affected by CS, but CS2 rats exhibited higher sympathetic tone (-25 ± 4 vs. -28 ± 4 vs. -56 ± 9) and lower intrinsic HR (411 ± 4 vs. 420 ± 8 vs. 390 ± 6). Exposure to CS of 2 cigarettes also exacerbated the reflex cardiovascular and ventilatory responses to hypoxia and hypercapnia.

Significance: CS exposure for 30 days promoted systemic changes and autonomic cardiocirculatory dysfunction in rats depending on the daily exposure dose.
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http://dx.doi.org/10.1016/j.lfs.2021.119498DOI Listing
April 2021

Needle Trap Device-GC-MS for Characterization of Lung Diseases Based on Breath VOC Profiles.

Molecules 2021 Mar 22;26(6). Epub 2021 Mar 22.

Interdisciplinary Centre of Modern Technologies, Nicolaus Copernicus University in Toruń, 4 Wileńska St., 87-100 Toruń, Poland.

Volatile organic compounds (VOCs) have been assessed in breath samples as possible indicators of diseases. The present study aimed to quantify 29 VOCs (previously reported as potential biomarkers of lung diseases) in breath samples collected from controls and individuals with lung cancer, chronic obstructive pulmonary disease and asthma. Besides that, global VOC profiles were investigated. A needle trap device (NTD) was used as pre-concentration technique, associated to gas chromatography-mass spectrometry (GC-MS) analysis. Univariate and multivariate approaches were applied to assess VOC distributions according to the studied diseases. Limits of quantitation ranged from 0.003 to 6.21 ppbv and calculated relative standard deviations did not exceed 10%. At least 15 of the quantified targets presented themselves as discriminating features. A random forest (RF) method was performed in order to classify enrolled conditions according to VOCs' latent patterns, considering VOCs responses in global profiles. The developed model was based on 12 discriminating features and provided overall balanced accuracy of 85.7%. Ultimately, multinomial logistic regression (MLR) analysis was conducted using the concentration of the nine most discriminative targets (2-propanol, 3-methylpentane, ()-ocimene, limonene, -cymene, benzonitrile, undecane, terpineol, phenol) as input and provided an average overall accuracy of 95.5% for multiclass prediction.
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http://dx.doi.org/10.3390/molecules26061789DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8004837PMC
March 2021

Evaluation of salivary VOC profile composition directed towards oral cancer and oral lesion assessment.

Clin Oral Investig 2021 Jan 2. Epub 2021 Jan 2.

Interdisciplinary Centre of Modern Technologies, Nicolaus Copernicus University in Toruń, 4 Wileńska St., 87-100, Toruń, Poland.

Objectives: Endogenous substances have been analyzed in biological samples in order to be related with metabolic dysfunctions and diseases. The study aimed to investigate profiles of volatile organic compounds (VOCs) from fresh and incubated saliva donated by healthy controls, individuals with oral tissue lesions and with oral cancer, in order to assess case-specific biomarkers of oxidative stress.

Materials And Methods: VOCs were pre-concentrated using headspace-solid phase microextraction and analyzed using gas chromatography-mass spectrometry. Then, VOCs positively modulated by incubation process were subtracted, yielding profiles with selected features. Principal component analysis and hierarchical cluster analysis were used to inspect data distribution, while univariate statistics was applied to indicate potential markers of oral cancer. Machine learning algorithm was implemented, aiming multiclass prediction.

Results: The removal of bacterial contribution to VOC profiles allowed the obtaining of more specific case-related patterns. Artificial neural network model included 9 most relevant compounds (1-octen-3-ol, hexanoic acid, E-2-octenal, heptanoic acid, octanoic acid, E-2-nonenal, nonanoic acid, 2,4-decadienal and 9-undecenoic acid). Model performance was assessed using 10-fold cross validation and receiver operating characteristic curves. Obtained overall accuracy was 90%. Oral cancer cases were predicted with 100% of sensitivity and specificity.

Conclusions: The selected VOCs were ascribed to lipid oxidation mechanism and presented potential to differentiate oral cancer from other inflammatory conditions.

Clinical Relevance: These results highlight the importance of interpretation of saliva composition and the clinical value of salivary VOCs. Elucidated metabolic alterations have the potential to aid the early detection of oral cancer and the monitoring of oral lesions.
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http://dx.doi.org/10.1007/s00784-020-03754-yDOI Listing
January 2021

Study on Molecular Profiles of Strains: Spectrometric Approach.

Molecules 2020 Oct 22;25(21). Epub 2020 Oct 22.

Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University in Toruń, Wileńska 4 Str., 87-100 Toruń, Poland.

remains a major health problem responsible for many epidemic outbreaks. Therefore, the development of efficient and rapid methods for studying molecular profiles of strains for its further typing is in high demand. Among many techniques, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI TOF MS) represents a timely, cost-effective, and reliable strain typing approach, which is still rarely used due to insufficient knowledge about the impact of sample preparation and analysis conditions on the molecular profiles and strain classification efficiency of . The aim of this study was to evaluate the effect of the culture conditions and matrix type on the differentiation of molecular profiles of various strains via the MALDI TOF MS analysis and different computational methods. The analysis revealed that by changing the culture conditions, matrix type, as well as a statistical method, the differentiation of strains can be significantly improved. Therefore, to accelerate the incorporation of the MALDI-based strain typing in routine laboratories, further studies on the standardization and searching of optimal conditions on a larger number of isolates and bacterial species are of great need.
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http://dx.doi.org/10.3390/molecules25214894DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7660162PMC
October 2020

A Review of GC-Based Analysis of Non-Invasive Biomarkers of Colorectal Cancer and Related Pathways.

J Clin Med 2020 Oct 1;9(10). Epub 2020 Oct 1.

Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University in Toruń, 87-100 Toruń, Poland.

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in the world. In Europe, it is the second most common cause of cancer-related deaths. With the advent of metabolomics approaches, studies regarding the investigation of metabolite profiles related to CRC have been conducted, aiming to serve as a tool for early diagnosis. In order to provide further information about the current status of this field of research, 21 studies were systematically reviewed, regarding their main findings and analytical aspects. A special focus was given to the employment of matrices obtained non-invasively and the use of gas chromatography as the analytical platform. The relationship between the reported volatile and non-volatile biomarkers and CRC-related metabolic alterations was also explored, demonstrating that many of these metabolites are connected with biochemical pathways proven to be involved in carcinogenesis. The most commonly reported CRC indicators were hydrocarbons, aldehydes, amino acids and short-chain fatty acids. These potential biomarkers can be associated with both human and bacterial pathways and the analysis based on such species has the potential to be applied in the clinical practice as a low-cost screening method.
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http://dx.doi.org/10.3390/jcm9103191DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7601558PMC
October 2020

New Methodology for the Identification of Metabolites of Saccharides and Cyclitols by Off-Line EC-MALDI-TOF-MS.

Int J Mol Sci 2020 Jul 24;21(15). Epub 2020 Jul 24.

Centre for Modern Interdisciplinary Technologies Nicolaus Copernicus University in Toruń, Wileńska 4, 87-100 Toruń, Poland.

A combination of electrochemistry (EC) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry ( EC-MALDI-TOF-MS) was applied for determination of the studied biologically active compounds (D-glucose, D-fructose, D-galactose, D-pinitol, L--inositol, and -inositol) and their possible electrochemical metabolites. In this work, boron-doped diamond electrode (BDD) was used as a working electrode. MALDI-TOF-MS experiments were carried out (both in positive and negative ion modes and using two matrices) to identify the structures of electrochemical products. This was one of the first applications of the EC system for the generation of electrochemical products produced from saccharides and cyclitols. Moreover, exploratory data analysis approaches (correlation networks, hierarchical cluster analysis, weighted plots) were used in order to present differences/similarities between the obtained spectra, regarding the class of analyzed compounds, ionization modes, and used matrices. This work presents the investigation and comparison of fragmentation patterns of sugars, cyclitols, and their respective products generated through the electrochemistry (EC) process.
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http://dx.doi.org/10.3390/ijms21155265DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7432413PMC
July 2020

Investigation of Ayahuasca β-Carboline Alkaloids and Tryptamine in Sweat Samples from Religious Community Participants by GC-MS.

J Anal Toxicol 2020 Jul;44(6):601-609

Department of Chemistry, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, 3900 Av. Bandeirantes, SP 14050-140, Ribeirão Preto, Brazil.

Ayahuasca, a hallucinogenic beverage used in religious rituals in South America, has become a global phenomenon. Its main active components are the β-carbolines alkaloids, harmine (HRM) and harmaline (HRL), as well as the potent hallucinogen N,N-dimethyltryptamine (DMT). Despite its rising consumption, information regarding possible clinical applications and toxicological effects of ayahuasca is still limited. This study presents the first investigation of the use of sweat for the determination of DMT, HRM and HRL in ayahuasca users during a religious ritual. Sweat is an alternative matrix with advantages over many conventional biological samples, mainly because the collection procedure is non-invasive, easy and simple and samples can be collected without disturbing the religious ritual. In the study, solid-phase extraction was performed under basic conditions. Linearity was observed ranging from 20 to 1500 ng/patch with coefficients of determination (R2) higher than 0.99 for all analytes. The results indicated high selectivity for all investigated analytes, with extraction efficiency exceeding 70%, accuracy ranging from 87.5 to 102.4%, intra-assay precision of 1.85-9.44% and inter-assay precision between 3.34 and 9.85%. The limits of detection were 15 ng/patch for HRM and HRL and 10 ng/patch for DMT. The sweat proved to be a viable option to monitor ayahuasca use.
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http://dx.doi.org/10.1093/jat/bkz116DOI Listing
July 2020

Evolution and Evaluation of GC Columns.

Crit Rev Anal Chem 2021 10;51(2):150-173. Epub 2019 Dec 10.

Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University, Toruń, Poland.

A chromatographic column is the fundamental element required for gas-chromatographic analysis. The separation of components coming from complex mixtures, prior to their detection was leading to a prominent revolution in different areas of science. Moreover, current advances in gas chromatographic (GC) columns technology and development have been providing almost unlimited possibilities for analysis employing diverse matrices. We aim through this review article to describe the evolution of chromatographic columns, by pointing the most important stages, as well as the new trends and future perspectives predicted for the new generation of GC columns. Furthermore, it was in our scope to present the main fundamentals regarding the theoretical relationships that describe the chromatographic separation, to introduce concepts related to columns selection in accordance with the required application as well as to discuss the available evaluation parameters for columns efficiency. Consequently, the early stages of first columns preparation up to the development of GC capillary columns used nowadays, together with examples of their applications are also reported and described in detail.
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http://dx.doi.org/10.1080/10408347.2019.1699013DOI Listing
December 2019

Investigation of sweat VOC profiles in assessment of cancer biomarkers using HS-GC-MS.

J Breath Res 2020 02 25;14(2):026009. Epub 2020 Feb 25.

Department of Chemistry, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo, Ribeirão Preto, CEP 14040-901, Brazil.

Volatile organic compounds (VOCs) have been studied in biological samples in order to be related to the presence of diseases. Sweat can represent substances existing in blood, has less complex composition (compared with other biological matrices) and can be obtained in a non-invasive way. In this work, sweat patches were collected from healthy controls and volunteers with cancer. Static Headspace was used for VOCs extraction, analysis was performed by gas chromatography coupled with mass spectrometry. Principal Components Analysis was used to investigate data distribution. Random Forest was employed to develop classificatory models. Controls and positive cases could be distinguished with maximum sensitivity and specificity (100% of accuracy) in a model based on the incidence of 2-ethyl-1-hexanol, hexanal and octanal. Discrimination between controls, primary tumors and metastasis was achieved using a panel with 11 VOCs. Balanced accuracy of more than 70% was obtained for the classification of a neoplasm site. Total n-aldehydes presented to be strongly correlated with staging of adenocarcinomas, while phenol and 2,6-dimethyl-7-octen-2-ol were correlated with Gleason score. These findings corroborate with the development of accessible screening tools based on VOC analysis and highlight sweat as a promising matrix to be studied in a clinical context for cancer diagnosis.
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http://dx.doi.org/10.1088/1752-7163/ab5b3cDOI Listing
February 2020

Monitoring of Bactericidal Effects of Silver Nanoparticles Based on Protein Signatures and VOC Emissions from and Selected Salivary Bacteria.

J Clin Med 2019 Nov 19;8(11). Epub 2019 Nov 19.

Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University, 87-100 Toruń, Poland.

and salivary and were subjected to different concentrations of silver nanoparticles (AgNPs), namely: 12.5, 50, and 100 µg mL. Matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) spectra were acquired after specified periods: 0, 1, 4, and 12 h. For study of volatile metabolites, headspace solid-phase microextraction coupled to gas chromatography/mass spectrometry (HS-SPME-GC-MS) was employed-AgNPs were added to bacteria cultures and the headspace was analyzed immediately and after 12 h of incubation. Principal components analysis provided discrimination between clusters of protein profiles belonging to different strains. Canonical correlation, network analysis, and multiple linear regression approach revealed that dimethyl disulfide, dimethyl trisulfide, 2-heptanone, and dodecanal (related to the metabolism of sulfur-containing amino acids and fatty acids synthesis) are exemplary molecular indicators, whose response variation deeply correlated to the interaction with bacteria. Therefore, such species can serve as biomarkers of the agent's effectiveness. The present investigation pointed out that the used approaches can be useful in the monitoring of response to therapeutic treatment based on AgNPs. Furthermore, biochemical mechanisms enrolled in the bactericidal action of nanoparticles can be applied in the development of new agents with enhanced properties.
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http://dx.doi.org/10.3390/jcm8112024DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6912796PMC
November 2019

An Optimistic Vision of Future: Diagnosis of Bacterial Infections by Sensing Their Associated Volatile Organic Compounds.

Crit Rev Anal Chem 2020 12;50(6):501-512. Epub 2019 Sep 12.

Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University, Toruń, Poland.

Simple tests using sniff analysis that have the ability of diagnosing and rapidly distinguishing between infections due to different bacteria are urgently required by medical community worldwide. Professionals interested in this topic wish for these tests to be simultaneously cheap, fast, easily applicable, non-invasive, robust, reliable, and sensitive. Current analytical instrumentation has already the ability for performing real time (minutes or a few dozens of minutes) analysis of volatile bacterial biomarkers (the VOCs emitted by bacteria). Although many articles are available, a review displaying an objective evaluation of the current status in the field is still needed. This review tries to present an overview regarding the bacterial biomarkers released from cultivation of various bacterial strains and also from different biological matrices investigated, over the last 10 years. We have described results of relevant studies, which used modern analytical techniques to evaluate specific biomarker profiles associated with bacterial infections. Our purpose was to present a comprehensive view of available possibilities for detection of emitted bacterial VOCs from different matrices. We intend that this review to be of general interest for both medical doctors and for all researchers preoccupied with bacterial infectious diseases and their rapid diagnosis using analytical instrumentation.
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http://dx.doi.org/10.1080/10408347.2019.1663147DOI Listing
February 2021

VOC Profiles of Saliva in Assessment of Halitosis and Submandibular Abscesses Using HS-SPME-GC/MS Technique.

Molecules 2019 Aug 16;24(16). Epub 2019 Aug 16.

Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University, 7 Gagarina Str., 87-100 Toruń, Poland.

Halitosis and submandibular abscesses are examples of mouth-related diseases with the possible bacterial origin. Salivary volatile organic compounds (VOCs) are potential biomarkers of them, once they can be addressed as metabolites of bacterial activity. Healthy patients (n = 15), subjects with submandibular abscesses located in fascial deep space (n = 10), and subjects with halitosis (n = 5) were enrolled in the study. Saliva samples were subjected to headspace solid-phase microextraction (HS-SPME) and gas chromatography coupled to mass spectrometry (GC/MS) analysis. A total number of 164 VOCs was detected by the developed methodology, 23 specific for halitosis and 41 for abscess. Halitosis' profiles were characterized by a larger number of sulfur compounds, while for abscess they had a higher variety of alcohols, aldehydes, and hydrocarbons-biomarkers of inflammatory processes. Principal components analysis allowed visualization of clusters formed according to the evaluated conditions. Kruskal-Wallis test indicated that 39 VOCs presented differentiated responses between the studied groups, with statistical relevance (p < 0.05). Random forest was applied, and a prediction model based on eight VOCs (2-butanone, methyl thioacetate, 2-methylbutanoic acid, S-methyl pentanethioate, dimethyl tetrasulfide, indolizine, pentadecane, and octadecanal) provided 100% of sensitivity, 82% of specificity, and 91% of balanced accuracy, indicating the specific presence of submandibular abscess.
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http://dx.doi.org/10.3390/molecules24162977DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6720996PMC
August 2019

Profiling of VOCs released from different salivary bacteria treated with non-lethal concentrations of silver nitrate.

Anal Biochem 2019 08 11;578:36-44. Epub 2019 May 11.

Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University, 7 Gagarina Str, 87-100, Toruń, Poland; Interdisciplinary Centre of Modern Technologies, Nicolaus Copernicus University, 4 Wileńska Str, 87-100, Toruń, Poland. Electronic address:

Considering the shortcomings related to antibiotics usage, the introduction of other bacteriostatic and bactericidal agents that present synergetic effects or standalone properties is urgently needed. AgNO is an important bactericidal agent, which imparts various functions on bacteria dependent on its concentration. Therefore, an understanding of its mechanisms of action in infinitesimal concentrations plays an important role which can ultimately lead to AgNO involvement in the pharmaceutical industry. The monitoring of VOC (volatile organic compound) profiles emitted by bacteria is a simple method to assess changes occurring in bacterial metabolism. In this study, VOCs of Hafnia alvei, Pseudomonas luteola and Staphylococcus warneri cultures were analyzed both in the absence and in the presence of three concentrations of AgNO. Headspace solid-phase microextraction gas chromatography/mass spectrometry (HS-SPME-GC/MS) was employed for extraction and analysis. After supplementation with AgNO, changes in the emitted fingerprints were investigated. Odorants associated with mouth-related and systemic diseases, like dimethyl trisulfide, indole (halitosis) and 2-hexanone (celiac disease), were also affected by addition of AgNO. Statistical tests proved discrimination between obtained profiles with more that 90% variability. Moreover, physiological states of bacteria after dosage with various concentration of stressing agent were investigated and explained by the mechanisms of action.
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http://dx.doi.org/10.1016/j.ab.2019.05.007DOI Listing
August 2019