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To further develop Liupao tea products and enhance their flavor, this study investigated the effects of different fermentation methods on the aroma quality of Liupao tea. The aroma quality of Liupao tea was comprehensively analyzed using HS-SPME in combination with GC-Q-TOF-MS, electronic nose, and sensory evaluations. Electronic nose detection showed that the aroma fingerprints of Liupao tea samples with different fermentation methods were different. Sulfides, alcohols, ketones, and methyls were the main aroma categories affecting the aroma of the four groups of Liupao tea samples. GC-Q-TOF-MS analysis revealed significant differences in the composition of aroma components among the four fermentation methods of Liupao tea (p < 0.05). Furthermore, the total amount of aroma compounds was found to be highest in the group subjected to hot fermentation combined with the inoculation of Monascus purpureus (DMl group). Based on the OPLS-DA model, candidate differential aroma components with VIP > 1 were identified, and characteristic aroma compounds were selected based on OAV > 10. The key characteristic aroma compounds shared by the four groups of samples were 1,2,3-Trimethoxybenzene with a stale aroma and nonanal with floral and fruity aromas. The best sensory evaluation results were obtained for the DMl group, and its key characteristic aroma compounds mainly included 1,2,3-Trimethoxybenzene, nonanal, and cedrol. The results of this study can guide the development of Liupao tea products and process optimization.

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Organophosphorus flame retardants (OPFRs) have emerged as good alternatives to brominated flame retardants, the use of which is globally restricted. In this study, a screening method based on QuEChERS-gas chromatography-quadrupole time-of-flight mass spectrometry (GC-Q-TOF/MS) was established for the determination of 21 OPFRs in rice. First, full scan (scanning range, m/z 50-450) was performed with a mixed standard solution of the 21 OPFRs (0.1 µg/g) by GC-Q-TOF/MS. The fragmentation pathways of these OPFRs were then investigated to explore their cleavage fragments, the interrelationships among fragments, and the possible cleavage modes of alkylated, chlorinated, and aromatic OPFRs. The retention times, isotopic abundance ratios, and molecular formulas of the characteristic fragments as well as the exact mass of the compounds were obtained to establish a mass spectral library of the OPFRs. Rice samples were extracted and purified by the QuEChERS method, and 0.5% formate acetonitrile solution was used as the extraction solvent; 4 g of magnesium sulfate, 1 g of sodium chloride, 0.5 g of disodium hydrogen citrate, and 1 g of sodium citrate as the extraction-salt combination; and 50 mg of primary secondary amine (PSA), 50 mg of octadecylsilane (C18), and 150 mg of magnesium sulfate as the purification materials. The chromatographic separation of the 21 OPFRs was completed within 16 min under optimized temperature program conditions on the DB-5MS UI column. The screening parameters were optimized, and a full scan of the samples was performed under the following conditions: number of characteristic fragment ions ≥2; accurate mass window=±2×10-5 (±20 ppm); retention time deviation=±0.2 min, and ion abundance deviation<20%. The developed method was applied to the screening 21 OPFRs in the samples. The results indicated that the matrix interference was greatly reduced by decreasing the extraction accurate mass window, thereby improving the signal-to-noise ratio of the analytes. The targets were extracted from the matrix interference and background noise using deconvolution software, which improved the match between the target compounds and the mass spectral library. The detection rates of alkyl and aromatic OPFRs increased by 22% and 25%, respectively, when the spiking level was increased from 2 to 10 ng/g. Among the chlorinated OPFRs, only tris(2-chloroisopropyl) phosphate (TCIPP) was not detected at a spiking level of 2 ng/g, indicating that chlorinated OPFRs could be identified even at low concentrations. The characteristic ions of the detected compounds matched those of the home-made mass spectral library well, indicating that the practical application of the home-made mass spectral library. The established screening method was applied in the determination of OPFRs in rice samples from different regions in China. A total of 11 OPFRs were detected, among which trimethyl phosphate (TMP), tri-iso-butyl phosphate (TiBP), and tris(3,5-dimethylphenyl) phosphate (T35DMPP) had the highest detection rates. These results indicate that these three OPFRs are widely used and can easily come into contact with rice samples through various routes. Differences in the types of OPFRs detected in the actual samples may be related to the types of OPFRs produced in local factories. OPFRs can be detected in rice samples by the developed GC-Q-TOF/MS screening method, which is helpful for the identification of OPFRs in complex matrix samples.

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Restrictions on the use of phthalates have led to the wide use of alternative plasticizers (APs) such as organophosphate, adipate, citrate, and sebacate. However, because plasticizers combine with polymers in plastic products via unstable noncovalent bonds, they can easily migrate out of these products, causing environmental pollution. In particular, their migration out of food packaging, containers, and other food-contact materials and into food has raised great concerns. Toxicological studies have shown that APs contain potentially toxic substances that can affect endocrine functions and cause neurotoxicity, genotoxicity, and other adverse effects. Thus, their potential risks to food should not be underestimated. Sesame oil is a necessity in daily cooking. The results of risk monitoring in recent years have indicated that sesame oil often contains phthalates in excess of the standard limits. However, the potential risks of APs in sesame oil have not yet been reported. Some common detection methods for APs include gas chromatography-mass spectrometry, gas chromatography-triple quadrupole mass spectrometry, and liquid chromatography-triple quadrupole mass spectrometry. Unfortunately, these methods use low-resolution mass spectrometry and are limited by the resolution, scan rate, and analysis mode. Gas chromatography-quadrupole time-of-flight mass spectrometry (GC-Q-TOF/MS) has the advantages of high resolution, sensitivity, and analysis speed. In full-scan mode, GC-Q-TOF/MS can accurately collect the full-spectrum mass number of target compounds with low content levels in complex substrates, thereby realizing efficient screening and quantitative analysis. It shows outstanding advantages in the trace analysis of pesticide residues and pollutants. Furthermore, it features strong qualitative and high screening abilities. Establishment of a personal compound database and library (PCDL) addresses limitations in the number of compounds that can be measured and enables the rapid identification of targets without the use of standard products. In addition, increasing the number of targets for synchronous screening enables the retrospective analysis of new targets. In this study, a method based on GC-Q-TOF/MS was developed for the determination of 54 APs in sesame oil. The samples were extracted with acetonitrile and purified using a PSA/silica solid-phase extraction column. The mass-spectral information of the samples was then collected by GC-Q-TOF/MS in full-scan mode, and the 54 APs were searched using an established high-resolution mass-spectrum database to simultaneously achieve the broad-spectrum screening, qualitative identification, and quantitative analysis of multiple targets. The effects of different extraction solvents and purification methods on sample extraction and purification were compared. The accuracy of the screening results was improved by optimizing the GC-separation conditions, quality-extraction window, retention-time deviation, and other screening parameters. The screening detection limits (SDLs) of the 54 APs ranged from 0.01 to 0.02 mg/kg; specifically, the SDL of 41 compounds was 0.01 mg/kg and that of 13 compounds were 0.02 mg/kg. The limits of quantification were in the range of 0.02-0.04 mg/kg. A total of 80 sesame-oil samples were rapidly screened using this method under optimal conditions. Five APs were identified from the 80 sesame-oil samples and quantitatively analyzed using the matrix-matched external-standard method. The results of this quantitative methodology showed that the five APs had good linear relationships in the range of 0.01-0.2 mg/L, with all correlation coefficients greater than 0.99. The accuracy and precision of the method were verified using a standard recovery test with blank sesame-oil samples. Under the three standard levels of 0.04, 0.08, and 0.2 mg/kg, the recoveries of the five APs ranged from 71.3% to 97.8%, and the relative standard deviations (RSDs) ranged from 0.4% to 6.1%(n=6). The developed method is fast, accurate, sensitive, and has high throughput. Thus, it can realize the efficient screening, qualitative identification, and quantitative analysis of the 54 APs in sesame oil and provides a potential solution for the monitoring of other contaminants in food.

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Carum carvi L. belongs to the Apiaceae family and is widely used as a vegetable, food spice, preservative, and herbal medicine. This study investigated the impact of essential oil extracted from Carum carvi L. seeds (CEO) on methicillin-resistant Staphylococcus aureus (MRSA) and its possible action mechanism. The dominant chemical components of CEO determined by GC-MS were carvone and limonene. It was observed that CEO had a considerable inhibitory effect against the growth of planktonic bacteria and biofilm in MRSA cells. Untargeted metabolomics based on GC-Q-TOF-MS was used to analyze the possible mechanism of the interaction of MRSA with CEO. It was determined that there were 63 different metabolites based on fold change values greater than 1.5 or less than 1.5, p < 0.05, VIP > 1, which demonstrated amino acid metabolism in MRSA was significantly affected by CEO. In conclusion, CEO has a potent antimicrobial property and has promising potential for use in food and drugs.

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Tegoprazan is a novel orally active potassium-competitive acid blocker (P-CAB), capable of binding to the K+ binding site of H+/K+-ATPase in a reversible way to inhibit gastric acid secretion. Tegoprazan has been approved for treating acid-related diseases. In this study, stress testings of tegoprazan were performed under various conditions, including hydrolysis (acidic, alkaline, and neutral), oxidation, photolysis, and thermal stress. Tegoprazan showed instability in acidic, alkaline, and oxidative conditions. Eight degradation products (DPs) were identified. The DPs were characterized by LC-HRMS, LC-MSn, or GC-Q-TOF-MS. Meanwhile, DP-1, DP-2 and DP-3 were successfully synthesized and confirmed by NMR. The degradation pathway of tegoprazan was summarized. To the best of our knowledge, this is the first study on the forced degradation of tegoprazan.

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Sample preparation remains both a challenging and time-consuming process in the field of bioanalytical chemistry. Many traditional techniques often require multi-step processes, which can introduce additional errors to the analytical method. Given the complexity of many biological matrices, thorough analyte extraction presents a major challenge to researchers. In the present study, a headspace solid-phase microextraction (HS-SPME) coupled with a GC/Q-ToF-MS method, was developed to quantify in vitro metabolism of ß-caryophyllene by both human liver microsome (HLM) and S9 liver fractions. Validation of the method was demonstrated both in terms of linearity (R2 = 0.9948) and sensitivity with a limit of detection of 3 ng/mL and a limit of quantitation of 10 ng/mL. In addition, the method also demonstrated both inter- and intra-day precision with the relative standard deviation (RSD) being less than 10% with four concentrations ranging from 50-500 ng/mL. Since this method requires no solvents and minimal sample preparation, it provides a rapid and economical alternative to traditional extraction techniques. The method also eliminates the need to remove salts or buffers, which are commonly present in biological matrices. Although this method was developed to quantify in vitro metabolism of one analyte, it could easily be adapted to detect or quantify numerous volatiles and/or semi-volatiles found in biological matrices.

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Sweet pickled mango named Ma-Muang Bao Chae-Im (MBC), a delicacy from the Southern part of Thailand, has a unique aroma and taste. The employed immersion processes (brining 1, brining 2, and immersion in a hypertonic sugar solution, sequentially) in the MBC production process bring changes to the unripe mango, which indicate the occurrence of metabolic profiles alteration during the production process. This occurrence was never been explored. Thus, this study investigated metabolic profile alteration during the MBC production process. The untargeted metabolomics profiling method was used to reveal the changes in volatile and non-volatile metabolites. Headspace solid-phase micro-extraction tandem with gas chromatography quadrupole time of flight (GC/QTOF) was employed for the volatile analysis, while metabolites derivatization for non-volatile analysis. In conclusion, a total of 82 volatile and 41 non-volatile metabolites were identified during the production process. Terpenes, terpenoids, several non-volatile organic acids, and sugars were the major mango metabolites that presented throughout the process. Gamma-aminobutyric acid (GABA) was only observed during the brining processes, which suggested the microorganism's stress response mechanism to an acidic environment and high chloride ions in brine. Esters and alcohols were abundant during the last immersion process, which had an important role in MBC flavor characteristics. The knowledge of metabolites development during the MBC production process would be beneficial for product development and optimization.

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Members of the genus Salvia are used as culinary herbs and are prized for their purported medicinal attributes. Since physiological effects can vary widely between species of Salvia, it is of great importance to accurately identify botanical material to ensure safety for consumers. In the present study, an in-depth chemical investigation is performed utilizing GC/Q-ToF combined with chemometrics. Twenty-four authentic plant samples representing five commonly used Salvia species, viz. S. apiana, S. divinorum, S. mellifera, S. miltiorrhiza, and S. officinalis, are analyzed using a GC/Q-ToF technique. High-resolution spectral data are employed to construct a sample class prediction (SCP) model followed by principal component analysis (PCA) and partial least square discriminant analysis (PLS-DA). This model demonstrates 100% accuracy for both prediction and recognition abilities. Additionally, the marker compounds present in each species are identified. Furthermore, to reduce the time required and increase the confidence level for compound identification and the classification of different Salvia species, a personal compound database and library (PCDL) containing marker and characteristic compounds is constructed. By combining GC/Q-ToF, chemometrics, and PCDL, the unambiguous identification of Salvia botanicals is achieved. This high-throughput method can be utilized for species specificity and to probe the overall quality of various Salvia-based products.

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Pressurized liquid extraction (PLE) conditions were optimized to improve the recovery of orange (Citrus sinensis) by-products terpenoids. The neuroprotective potential of the PLE extracts were tested against a set of in-vitro assay (antioxidant (ABTS), reactive oxygen/nitrogen species (ROS/RNS)) as well as enzymatic tests (acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and lipoxygenase (LOX)). Gas chromatography coupled to high-resolution mass spectrometry (GC-q-TOF-MS) analysis revealed a higher enrichment in mono- and sesquiterpenoids of the PLE extracts with the highest neuroprotection capacity. In-silico molecular docking analysis showed the specific interaction of representative terpenoids with enzymes active sites. The results demonstrate that the selected extract at 100 °C and 30 minutes possesses high antioxidant (ABTSIC50 = 13.5 µg mL-1; ROSIC50 = 4.4 µg mL-1), anti-cholinesterase (AChEIC50 = 137.1 vg  L-1; BChEIC50 = 147.0 µg mL-1) and anti-inflammatory properties (against IL-6 and LOXIC50 = 76.1 µg mL-1), with low cytotoxicity and protection against L-glutamic acid in cell models.

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Emissions from the incineration of solid waste are a global public health concern, but little attention has been paid to previously unrecognized chemical compounds that are generated by waste incineration and released into the atmosphere. We conducted nontarget analysis of organic chemicals formed during waste incineration by Fourier-transform ion cyclotron resonance mass spectrometry and gas chromatography-quadrupole time-of-flight mass spectrometry. Using toxicity data in the ToxCast library and predicted toxicity data for traditional priority polycyclic aromatic hydrocarbons and 2,3,7,8-tetrachlorodibenzo-p-dioxin, we prioritized 13 compounds including hexachloro-1,3-butadiene, 9 of which are reported here for the first time as constituents of emissions from the incineration of solid waste and hexachloro-1,3-butadiene was included in the Stockholm Convention in 2017. The predicted activity of these pollutants to androgen receptors and to the aryl hydrocarbon receptor were comparable to, or higher than, the 2,3,7,8-tetrachlorodibenzo-p-dioxin and benzo[a]pyrene. In addition, some alkylated polycyclic aromatic hydrocarbons and heteroatom polycyclic aromatic hydrocarbons were also identified in solid waste incineration processes, peak areas of which were 1-2 orders of magnitude higher than dioxins and 1-3 orders of magnitude lower than their parent polycyclic aromatic hydrocarbons. Our study can provide information for better recognizing and regulating the emissions of organic pollutants formed by the incineration of solid waste.

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Agrifood by-products and microalgae represent a low-cost and valuable source of bioactive compounds with neuroprotective properties. However, the neuroprotective effectiveness of therapeutic molecules can be limited by their capacity to cross the blood-brain barrier (BBB) and reach the brain. In this research, various green extracts from Robinia pseudoacacia (ASFE), Cyphomandra betacea (T33), Coffea arabica (PPC1), Olea europaea L., (OL-SS), Citrus sinensis (PLE100) by-products and from the microalgae Dunaliella salina (DS) that have demonstrated in vitro neuroprotective potential were submitted to an in vitro BBB permeability and transport assay based on an immortalized human brain microvascular endothelial cells (HBMEC) model. Toxicity and BBB integrity tests were performed, and the transport of target bioactive molecules across the BBB were evaluated after 2 and 4 h of incubation using gas and liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (GC/LC-Q-TOF-MS). The HBMEC-BBB transport assay revealed a high permeability of representative neuroprotective compounds, such as mono- and sesquiterpenoids, phytosterols and some phenolic compounds. The obtained results from the proposed in vitro BBB cellular model provide further evidence of the neuroprotective potential of the target natural extracts, which represent a promising source of functional ingredients to be transferred into food supplements, food additives, or nutraceuticals with scientifically supported neuroprotective claims.

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QuEChERS pretreatment combined with gas chromatography-quadrupole time-of-flight mass spectrometry (GC-Q-TOF/MS) has been investigated for application in screening 244 pesticide residues in chilli. Fresh chilli samples were extracted with acetonitrile, and dried chilli samples were extracted using an acetonitrile/acetic acid (99∶1, v/v) mixture. The two extraction solvents were stored at -20 ℃. After salting out and cleaning by dispersive solid phase extraction (dSPE), heptachlor epoxide B was added as an internal standard, and the resulting residues were dissolved in 1.00 mL acetone. The dissolved sample solution was loaded onto an HP-5MS UI column (30 m×0.25 mm, 0.25 µm) and eluted by GC-Q-TOF/MS with a programmable temperature vaporizer and splitless injection in the full-scan mode. The compensation effects of the analytical protectant (AP) and matrix-matched calibration method on the matrix effect were established. AP could be used in the fresh chilli matrix to compensate for matrix effects, but it was not effective in the dried chilli matrix. The matrix-matched calibration method was effective in both matrices, which was selected for the quantification of pesticide residues in the samples. Because of the existence of the isomers of one compound and the same characteristic ions of different compounds, analyte detection was based on a flexible retention time deviation of ±0.25 min and accurate mass deviation of ±20×10 -6. Screening was performed by the software in the automatic matching mode. Compound identification and quantitation were based on a database and calibration curve established with reference materials. Suspicious samples were subjected to manual analysis. Quantitative analysis of 244 pesticide residues in fresh chilli and 222 pesticide residues in dried chilli was performed. The results showed that the developed database and method can provide a reference for the high-throughput screening and quantitation of fresh and dried chilli. Different levels of pesticides were added to the blank chilli samples, and the addition level corresponding to a signal-to-noise ratio (S/N) of 10 was used as the limit of quantification (LOQ). The LOQs of 44 pesticides with a maximum residue limit (MRL) ≤0.05 mg/kg in fresh chilli did not exceed 0.010 mg/kg. The linear ranges of these 44 pesticides were 0.01-1.00 mg/L. At spiked levels of the LOQ and 2.5 times the LOQ, the ratios of the 44 pesticides with recoveries of 60% to 120% were 88.64% and 100%, respectively. The LOQs of 200 pesticides with MRLs ≥0.05 mg/kg or without MRLs in fresh chilli did not exceed 0.025 mg/kg. The linear ranges of these 200 pesticides were 0.05-1.00. At spiked levels of the LOQ, twice the LOQ, and 10 times the LOQ, the ratios of the 200 pesticides with recoveries of 60% to 120% were 49.50%, 87.00%, and 89.50%, respectively. The linear correlation coefficients (r 2) of the 244 pesticides in fresh chilli were greater than 0.99. The LOQs of 222 pesticides in dried chilli were less than 0.15 mg/kg, and the linear ranges were 0.04-1.00 mg/L. The ratios of these 222 pesticides with r 2 greater than 0.99 was 95.46%. At spiked levels of the LOQ, twice the LOQ and 10 times the LOQ in dried chilli, the ratio of the 222 pesticides with recoveries of 60% to 120% were 72.52%, 73.42%, and 81.53%, respectively. The established screening and confirmation method was used to analyze 12 fresh chilli samples and 14 dried chilli samples. Eight pesticides were found in nine fresh chilli samples and three dried chilli samples, all of which were confirmed to be positive after manual identification. The concentrations of these pesticides were lower than the MRLs required by GB 2763-2019: National Food Safety Standard Maximum Residue Limits for Pesticides in Food. The results demonstrate that the established method is rapid, easy to execute, efficient, and reliable. It can be used for the high-throughput screening and quantitation of pesticide residues in fresh and dried chilli.

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Emissions of numerous targeted and non-targeted organic pollutants from industrial activities are one of the major contributors to the global air pollution. However, comprehensive recognition of their molecular characterization and real industrial scale mechanisms have never been achieved. Herein, by using high resolution mass spectrometry, we firstly give an insight into the molecular characterization and mechanisms of organic pollutants formed on fly ashes from secondary smelting of Al, Cu, Pb, and Zn and electric arc furnace steel-making. We found that lipid-like, unsaturated hydrocarbon and carboxyl-rich alicyclic molecule-like structures were the major chemical classes. Methylation- and oxidation-related reactions were suggested to be the major formation mechanisms. The predominance of carboxyl-rich structures in the fly ash further proved the contribution of metallurgical industrial emissions to air pollution. Findings in this study could be significant for further understanding the contribution of industrial emissions to air pollutions and conducting their source emission control.

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Volatile compounds (VCs) and triglycerides (TGs) are the primary groups of constituents in the fruits of five well-known species used in traditional Chinese medicine (TCM), viz. Alpinia oxyphylla Miq. (AO), Alpinia katsumadai Hayata (AK), Amomum villosum Lour. (FAL), Amomum villosum Lour. var. xanthioides T. L. Wu et Senjen (FALX), and Amomum longiligulare T. L. Wu (FALO). The fruits of these species are morphologically similar and commonly used in both foods and TCM. Each species is purportedly endowed with different medicinal properties. Efficient and environmentally friendly methods are desirable for the quality control of these species. The current study attempted to establish both comprehensive profiles and quality standards for the five TCM species. External morphology characters were provided to distinguish 18 fruit samples belonging to the five species, which were collected from different geographical regions of China. The VCs of each sample were analyzed by SPME GC/Q-ToF. The identification of marker compounds from each species allowed for the differentiation of the fruits from the five plants. Characterization and quantification of 21 TGs were achieved using SFC/MS with an analysis time of less than 15 min. The complex TGs were unambiguously identified using the MS detection with correct attribution of the acyl group to the sn-2 position. Moreover, the quantification of TGs was improved by using reference standards whenever possible or a single standard strategy to determine multiple TGs. The validity of the proposed SFC/MS method was assessed by analyzing fatty acids from the hydrolysis and transesterification products of the same sample set using GC/MS. The quantification results from both TGs and fatty acids were consistent, and were further substantiated by chemometric analysis. To our knowledge, this is the first comprehensive study utilizing the morphology, VCs, and TGs for quality evaluation purpose of these five TCM species.

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There is an urge for traditional herbal remedies as an alternative to modern medicine in treating several ailments. Alangium salviifolium is one such plant, used traditionally to treat several diseases. In several reports, there are findings related to the use of this plant extract that demonstrate its therapeutic value. However, very few attempts have been made to identify the extensive metabolite composition of this plant. Here, we performed metabolite profiling and identification from the bark of A. salviifolium by extracting the sample in organic and aqueous solvents. The organic and aqueous extracts were fraction-collected using the Agilent 1260 Analytical Scale Fraction Collection System. Each of the fractions was analyzed on Liquid Chromatogaphy/Quadrupole Time-of-Flight LC/Q-TOF and Gas Chromatography/Quadrupole Time-of-Flight GC/instruments. The Liquid Chromatography/Mass Spectrometry (LC/MS) analyses were performed using Hydrophilic Ineraction Liquid Chromatography (HILIC), as well as reversed-phase chromatography using three separate, orthogonal reverse phase columns. Samples were analyzed using an Agilent Jet Stream (AJS) source in both positive and negative ionization modes. The compounds found were flavonoids, fatty acids, sugars, and terpenes. Eighty-one secondary metabolites were identified as having therapeutic potential. The data produced was against the METLIN database using accurate mass and/or MS/MS library matching. Compounds from Alangium that could not be identified by database or library matching were subsequently searched against the ChemSpider) database of over 30 million structures using MSMS data and Agilent MSC software.In order to identify compounds generated by GC/MS, the data were searched against the AgilentFiehn GCMS Metabolomics Library as well as the Wiley/NIST libraries.

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A novel valorization strategy is proposed in this work for the sustainable utilization of a major mango processing waste (i.e. mango seed kernel, MSK), integrating green pressurized-liquid extraction (PLE), bioactive assays and comprehensive HRMS-based phytochemical characterization to obtain bioactive-rich fractions with high antioxidant capacity and antiproliferative activity against human colon cancer cells. Thus, a two steps PLE procedure was proposed to recover first the non-polar fraction (fatty acids and lipids) and second the polar fraction (polyphenols). Efficient selection of the most suitable solvent for the second PLE step (ethanol/ethyl acetate mixture) was based on the Hansen solubility parameters (HSP) approach. A comprehensive GC- and LC-Q-TOF-MS/MS profiling analysis allowed the complete characterization of the lipidic and phenolic fractions obtained under optimal condition (100% EtOH at 150 °C), demonstrating the abundance of oleic and stearic acids, as well as bioactive xanthones, phenolic acids, flavonoids, gallate derivatives and gallotannins. The obtained MSK-extract exhibited higher antiproliferative activity against human colon adenocarcinoma cell line HT-29 compared to traditional extraction procedures described in literature for MSK utilization (e.g. Soxhlet), demonstrating the great potential of the proposed valorization strategy as a valuable opportunity for mango processing industry to deliver a value-added product to the market with health promoting properties.

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An integrated analytical methodology based on pressurized-liquid extraction (PLE) in two steps, followed by in vitro assays and liquid chromatography/gas chromatography coupled to high-resolution mass spectrometry (HRMS), was developed and applied for the isolation and characterization of potential bioactive metabolites from Passiflora mollissima seeds. PLE was proposed in two sequential steps: 1) recovery of the lipidic fraction using nonpolar solvents, and 2) recovery of the phenolic fraction from the defatted seeds' residue using polar solvents. Cyclohexane was selected as the most suitable extraction solvent for the seeds defatting process (20 min, 100 °C and 100 bar). PLE optimization by response surface methodology was carried out to obtain phenolics-rich extracts with the highest antioxidant activity. Optimal extraction yield (6.58%), total phenolic content (29.99 mg g-1), total flavonoids content (0.94 mg g-1) and antioxidant activity (6.94 mM trolox g-1 and EC50 of 2.66 µg mL-1) were obtained operating at 150 °C with EtOH (100%) as solvent. Untargeted and semi-targeted MS and MS/MS data-mining strategies were successfully implemented for the rapid and comprehensive profiling of the polar and lipidic PLE fractions analysed by UHPLC and GC, respectively, coupled to quadrupole time-of-flight mass spectrometry (q-TOF-MS/MS). Polyphenols-rich extracts from P. mollisima seeds were characterized for the first time applying this approach, showing a broad variety of flavonoids, genuine flavanols (e.g. (epi)fisetinidol) and abundant proanthocyanidins. This application can be considered a successful demonstration of the great potential of the proposed methodology to effectively obtain and characterize complex natural extracts with potential bioactivity, by making use of powerful integrated identification strategies to facilitate the challenging post-acquisition data processing of huge datasets generated by HRMS analysis.

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In this work, a multi-analytical platform that allows obtaining and characterizing high-added value compounds from natural sources is presented, with a huge potential in traditional medicine, natural products characterization, functional foods, etc. Namely, the proposed multi-analytical platform is based on the combination of pressurized liquid extraction (PLE), liquid chromatography (LC) and gas chromatography quadrupole time-of-flight mass spectrometry GC-q-TOF-MS(/MS), in vitro assays and modelling tools for guiding extraction optimization. As case study, goldenberry or cape gooseberry fruit (Physalys peruviana L.) was selected. In particular, the potential of P. peruviana calyces, an important by-product of goldenberry processing, as promising source of bioactive compounds was evaluated. Selection of the most suitable solvent for PLE was based on the Hansen solubility parameters (HSP) approach using 4ß-hydroxywithanolide E (4ßHWE) and withanolide E (WE) as target compounds due to their bioactive potential. A surface response methodology was further applied for the optimization of the PLE parameters: temperature (50, 100 and 150 °C) and solvent composition (% EtOH in the mixture EtOH/EtOAc). The effects of the independent variables on extraction yield, withanolides content (4ßHWE and WE), total phenolic content (TPC), total flavonoids content (TFC) and antioxidant activity (EC50 and TEAC) were evaluated in order to obtain withanolide-rich extracts from P. peruviana calyces. The extract obtained under optimal conditions (at 125 °C and 75% EtOH v/v) exhibited satisfactory extraction yield (14.7%) and moderate antioxidant activity (with an EC50 value of 77.18 µg mL-1 and 1.08 mM trolox g-1), with 4ßHWE and WE concentrations of 8.8 and 2.3 mg g-1, respectively. LC-q-TOF-MS/MS analysis of the extract allowed the quantitation of 4ßHWE and WE and the tentative identification of several other withanolides structures. The obtained results demonstrate the great potential of this multi-analytical approach for developing valorisation strategies of food by-products under sustainable conditions, to obtain bioactive-enriched extracts with potential medicinal or health-promoting properties.

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A multi-analytical strategy for the valorisation of goldenberry calyx, a promising source of health-promoting compounds, is presented in this work. A comprehensive characterization of P. peruviana calyx extracts, obtained by an optimized pressurized liquid extraction (PLE) procedure, is developed applying first an ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight tandem mass spectrometry (UPLC-ESI-q-TOF-MS/MS) method in positive and negative electrospray ionization (ESI) mode. A total of fifty-six phytochemicals, including major phenolic components, several withanolides (C28-isoprenoids) with a variety of biological activities, and a large family of anti-inflammatory sucrose esters were tentatively identified using this methodology. An integrated identification strategy based on accurate mass data obtained by high resolution mass spectrometry (HRMS), ion source fragmentation, MS/MS fragmentation patterns, generated molecular formulae and subsequent unsaturation degree calculation, along with database and bibliographic search is proposed. Isobaric withanolides-type compounds were tentatively identified or classified according to their different hydroxy and epoxy positions, on the basis of the complementary information provided by MS/MS product ion spectra obtained in both ESI+ and ESI- mode. The proposed structural elucidation approach provides a valuable contribution to the limited information available regarding the MS/MS structural analysis of withanolides in ESI(-) mode. Moreover, an alternative elucidation strategy based on deconvolution and database search was successfully applied for the phytochemical profiling analysis of the volatile fraction of P. peruviana calyx extracts by gas chromatography quadrupole time-of-flight mass spectrometry (GC-q-TOF-MS), which reveals the presence of relevant terpenoids, including phytosterols and tocopherols (Vitamin E). The results of the phytochemical characterization obtained herein demonstrates the great potential of applying integrated identification strategies to HRMS data obtained from complementary LC- and GC-q-TOF-MS(/MS) platforms, as powerful identification tools for improving our understanding on the phytochemical composition of natural extracts intended to be used in functional foods or in traditional medicine preparations.

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This work presents a strategy for elucidation of unknown migrants from plastic food contact materials (baby bottles) using a combination of analytical techniques in an untargeted approach. First, gas chromatography (GC) coupled to mass spectrometry (MS) in electron ionisation mode was used to identify migrants through spectral library matching. When no acceptable match was obtained, a second analysis by GC-(electron ionisation) high resolution mass spectrometry time of flight (TOF) was applied to obtain accurate mass fragmentation spectra and isotopic patterns. Databases were then searched to find a possible elemental composition for the unknown compounds. Finally, a GC hybrid quadrupole-TOF-MS with an atmospheric pressure chemical ionisation source was used to obtain the molecular ion or the protonated molecule. Accurate mass data also provided additional information on the fragmentation behaviour as two acquisition functions with different collision energies were available (MS(E) approach). In the low-energy function, limited fragmentation took place, whereas for the high-energy function, fragmentation was enhanced. For less volatile unknowns, ultra-high pressure liquid chromatography-quadrupole-TOF-MS was additionally applied. Using a home-made database containing common migrating compounds and plastic additives, tentative identification was made for several positive findings based on accurate mass of the (de)protonated molecule, product ion fragments and characteristic isotopic ions. Six illustrative examples are shown to demonstrate the modus operandi and the difficulties encountered during identification. The combination of these techniques was proven to be a powerful tool for the elucidation of unknown migrating compounds from plastic baby bottles.

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