MetaboLightsapplication/xmlftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14209/m_MTBLS14209_LC-MS_alternating_reverse-phase_v2_maf.tsvftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14209/s_MTBLS14209.txtftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14209/i_Investigation.txtftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14209/a_MTBLS14209_LC-MS_alternating_reverse-phase.txtftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14209/FILES/DERIVED_FILES/LP3.mzMLftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14209/FILES/DERIVED_FILES/MRS2.mzMLftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14209/FILES/DERIVED_FILES/LP4.mzMLftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14209/FILES/DERIVED_FILES/MRS3.mzMLftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14209/FILES/DERIVED_FILES/LP1.mzMLftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14209/FILES/DERIVED_FILES/MRS1.mzMLftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14209/FILES/DERIVED_FILES/LP5.mzMLftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14209/FILES/DERIVED_FILES/LP2.mzMLprimaryOK200ftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14209<p>Substitute the integrated peak areas of all detected samples into the linear equation of the standard curve for calculation. Subsequently, apply the results to the calculation formula to ultimately determine the content of the substance in the actual samples.</p>MetaboLightsPublicLiquid Chromatography MS - alternating - reverse-phase<p>The sample extracts were analyzed using an LC-ESI-MS/MS system (UPLC, ExionLC AD https://</p><p>sciex.com.cn /; MS, QTRAP6500+System,https://sciex.com /). The analytical conditions were as follows,</p><p>HPLC:column,WatersACQUITYUPLCHSST3C18(100mm×2.1mmi.d. 1.8µm);solventsystem,water</p><p>with 0.1% formic acid (A), acetonitrile with 0.1% formic acid (B); The gradient was started at 10% B (0-1</p><p>min), increased to 95% B (1-6 min), 95% B (6-7 min), finaly ramped back to 10% B (7.1-10 min); flow rate,0.35 mL/min; temperature, 40°C; injection volume: 2 μL</p>Detection of metabolites in the supernatant of Lacticaseibacillus paracasei NCU-21.Peking UniversityDuo KeaiBacterial supernatantMRS mediummass spectrometry assay<p>After the sampleis thawed, 50μLsamplewasextractedwith250μLofmethanol. 10μL internal standard mixed solution (250 ng/mL) was added into the extract as internal standards (IS) for the quantication. Then the extract was vortexed for 3 min, then kept in a refrigerator at-20 °C for 30 min, centrifuge at 12000 r/min for 10 min at 4 °C, 150 μL of the supernatant was collected. The supernatant was again centrifuged at 12000 r/min for 5 min at 4 °C, 100 μL of the supernatant was transferred for further LC-MS analysis</p>Bacterial supernatantMRS mediumhttps://www.ebi.ac.uk/metabolights/MTBLS14209Tingtao Chen. Nanchang University. chentingtao1984@163.com.Kong Leilei. Nanchang University. heykong1999@163.com.<p>Based on a database constructed from standard compounds, qualitative analysis of the data obtained from mass spectrometry detection was performed.</p><p>Quantification was accomplished using the Multiple Reaction Monitoring (MRM) mode on a triple quadrupole mass spectrometer. In MRM mode, the first quadrupole filters the precursor ions (parent ions) of the target substance, excluding ions corresponding to compounds of other molecular weights to preliminarily eliminate interference. The precursor ions are then ionized and fragmented in the collision cell, producing multiple fragment ions. These fragment ions are subsequently filtered by the triple quadrupole to select the required characteristic fragment ions, thereby excluding non-target ion interference and ensuring more accurate and reproducible quantification.</p><p>After obtaining the mass spectrometry data from different samples, the chromatographic peaks of all target compounds were integrated, and quantitative analysis was performed using standard curves.</p>Groupkeaiduoduo998@126.com<p>Upon reaching the target growth phase, a defined volume of bacterial culture was rapidly transferred to pre-cooled centrifuge tubes. The cells were pelleted by centrifugation at 10,000 × g for 10 minutes at 4°C. The supernatant was then carefully aspirated and subjected to a two-step clarification process: it was first passed through a 0.22 µm sterile syringe filter to ensure complete removal of bacterial cells, followed by a second filtration through a 3 kDa molecular weight cut-off (MWCO) filter to remove proteins and other macromolecules. The resulting filtrate was immediately aliquoted, snap-frozen in liquid nitrogen, and stored at -80°C to prevent metabolite degradation prior to LC-MS analysis.</p>MetabolomicsBacterial supernatantMetabolomicscurtaingas (CUR) wasset at 35 psi, respectively. Tryptophan and its metabolites were analyzed using scheduled multiple reaction monitoring (MRM). Data acquisitions were performed using Analyst 1.6.3 software (Sciex).targeted analysis4400-5500Tryptophanion spray voltage (IS) 5500V Positive, -4500V (Negative)MRS mediumLacticaseibacillus paracaseiAB SCIEX QTRAP 6500+SCIEX ExionLC ADIndole-3-lactic acidLinear ion trap (LIT) and triple quadrupole (QQQ) scans were acquired on a triple quadrupole-linear ion trap mass spectrometer (QTRAP), QTRAP 6500+ LC-MS/MS System, equipped with an ESI Turbo Ion Spray interface, operating in both positive and negative ion mode and controlled by Analyst 1.6.3 software (Sciex). The ESI source operation parameters were as followssourcetemperature550CBacterial supernatantMetabolomicscurtaingas (CUR) wasset at 35 psi, respectively. Tryptophan and its metabolites were analyzed using scheduled multiple reaction monitoring (MRM). Data acquisitions were performed using Analyst 1.6.3 software (Sciex).targeted analysis4400-5500Tryptophanion spray voltage (IS) 5500V Positive, -4500V (Negative)MRS mediumLacticaseibacillus paracaseiAB SCIEX QTRAP 6500+SCIEX ExionLC ADIndole-3-lactic acidLinear ion trap (LIT) and triple quadrupole (QQQ) scans were acquired on a triple quadrupole-linear ion trap mass spectrometer (QTRAP), QTRAP 6500+ LC-MS/MS System, equipped with an ESI Turbo Ion Spray interface, operating in both positive and negative ion mode and controlled by Analyst 1.6.3 software (Sciex). The ESI source operation parameters were as followssourcetemperature550C<p>Linear ion trap (LIT) and triple quadrupole (QQQ) scans were acquired on a triple quadrupole-linear ion trap mass spectrometer (QTRAP), QTRAP 6500+ LC-MS/MS System, equipped with an ESI Turbo Ion Spray interface, operating in both positive and negative ion mode and controlled by Analyst 1.6.3 software (Sciex). The ESI source operation parameters were as follows: ion source, ESI+/-; sourcetemperature550C; ion spray voltage (IS) 5500V Positive, -4500V (Negative); curtaingas (CUR) wasset at 35 psi, respectively. Tryptophan and its metabolites were analyzed using scheduled multiple reaction monitoring (MRM). Data acquisitions were performed using Analyst 1.6.3 software (Sciex). Multiquant 3.0.3 software (Sciex) was 27 used to quantify all metabolites. Mass spectrometer parameters including the declustering potentials (DP) and collision energies (CE) for individual MRM transitions were done with further DP and CE optimization. Aspecific set of MRM transitions were monitored for each period according to the metabolites eluted within this period.</p>falseDetection of metabolites in the supernatant of Lacticaseibacillus paracasei NCU-21To investigate the important metabolites responsible for the antitumor activity of L. paracasei NCU-21, LC-MS/MS were employed for metabolomic analysis of the culture supernatant from L. paracasei NCU-21.2026-04-022026-04-02MTBLS14209