High resolution mass spectrometry targeted analysis and suspect screening of pesticide residues in fruit samples and assessment of dietary exposure.

Fruits consistently hold a prominent position in healthy dietary habits. Pesticides are used to manage plant diseases, achieve sustainable production, and maintain high food standards. This study utilized a comprehensive analytical technique that involved both targeted analysis and suspect screening. Analysis was conducted using Ultra-high-performance liquid chromatography coupled with hybrid Linear Trap Quadrupole (LTQ)/Orbitrap High Resolution Mass Spectrometry (HRMS) to examine pesticide levels in fruits. The matrices chosen comprised fruit commodities that are commonly consumed in Greece, including table grapes, apples, pears, citrus fruits, and strawberries. The QuEChERS approach was effectively validated for 30 specific pesticides. According to the method acceptance criteria established by SANTE, the QuEChERS method have shown exceptional efficiency in extracting the chosen pesticides, with recovery rates ranging from 70% to 120% in three concentration levels (10, 50, 100 µg kg-1). It also exhibited outstanding linearity, with an R2 more than 0.99. The method exhibited exceptional precision, with relative standard deviations (RSDs) below 20%. Additionally, the combined measurement uncertainty (MU%) was found to be acceptable, remaining below 50% The quantification limits were below 10 µg kg-1 for the majority of the analytes, satisfying the Maximum Residue Levels (MRLs) established by the European Commission. Following targeted analysis, a dietary risk assessment was performed, revealing that both acute and chronic hazard quotients (aHQ and cHQ), along with chronic hazard index (cHI) were below 1, which indicated that the studied commodities are safe for human consumption. In addition, a suspect screening workflow was developed based on an in-house database comprising 355 pesticides commonly applied to the relevant commodities and related transformation products (TPs). Overall, through suspect screening, twenty-two additional pesticides and TPs not included in the target list were identified. Hence, this approach is anticipated to function as proactive alert system guaranteeing the long-term viability of agricultural production.

Enrichment of Olive Oils with Natural Bioactive Compounds from Aromatic and Medicinal Herbs: Phytochemical Analysis and Antioxidant Potential.

Olive oil and herbs, two key components of the Mediterranean diet, are known for their beneficial effects on humans. In our study, we incorporated aromatic and medicinal herbs into local monovarietal olive oils via maceration procedures for enrichment. We identified the herbal-derived ingredients that migrate to olive oils and contribute positively to their total phenolic content and functional properties, such as radical scavenging activity. Thus, we characterized the essential oil composition of the aromatic herbs (GC-MS), and we determined the phenolic content and antioxidant capacity of the additives and the virgin olive oils before and after enrichment. The herbal phenolic compounds were analyzed by LC-LTQ/Orbitrap HRMS. We found that olive oils infused with Origanum vulgare ssp. hirtum, Rosmarinus officinalis and Salvia triloba obtained an increased phenolic content, by approximately 1.3 to 3.4 times, in comparison with the untreated ones. Infusion with S. triloba led to a significantly higher antioxidant capacity. Rosmarinic acid, as well as phenolic glucosides, identified in the aromatic herbs, were not incorporated into olive oils due to their high polarity. In contrast, phenolic aglycones and diterpenes from R. officinalis and S. triloba migrated to the enriched olive oils, leading to a significant increase in their phenolic content and to an improvement in their free radical scavenging capacity.

Target and suspect screening approaches for the identification of emerging and other contaminants in fish feeds using high resolution mass spectrometry.

Fish feed is essential in aquaculture fish production because, along with beneficial nutrients and components, many suspected compounds can be transferred to fish and ultimately to humans. In this context, a comprehensive analysis was conducted to monitor various pesticides and pharmaceutical compounds in aquaculture fish feed through target analysis and many other groups of chemicals via suspect screening approaches. In this study, the QuEChERS extraction method was optimized, validated, and applied to fifty-four fish feed samples collected from different production batches. This was followed by liquid chromatography-high-resolution linear ion trap/Orbitrap mass spectrometry (LC-HR-IT/Orbitrap-MS) for targeted and suspect screening purposes. In general, pesticides provided satisfactory recoveries (70-105.5 %), with quantification limits lower than 5 ng g-1, whereas pharmaceuticals displayed recoveries ranging from 70.5 to 120.2 %, with quantification limits below 25 ng g-1. In addition, the matrix effects and measurement uncertainty were assessed to provide more accurate and high-confidence results. Pirimiphos-methyl was detected and quantified in 20 of 54 fish feed samples (37 %) at concentrations <77 ng g-1. Finally, suspect screening revealed the occurrence of 10 mycotoxins (e.g., citrinin, aflatoxin G2, zearalenone, and alternariol), two pesticides excluding the target pesticides (tebuconazole and fenazaquin), perfluorooctane sulfonic acid (PFOS) in almost 2 % of the samples, and ethoxyquin (antioxidant), with 12 of its Transformation Products (TPs). Finally, suspect analysis incorporated in routine analyses have proven to have great potential for complete monitoring.

Aqueous fate of furaltadone: Kinetics, high-resolution mass spectrometry - based elucidation and toxicity assessment of photoproducts.

Furaltadone (FTD) is an antibiotic belonging to the nitrofurans group. It has been broadly used in livestock and aquaculture for therapeutic purposes, as well as for stimulating promotion. Although the European Union has imposed restrictions on the use of FTD since 1995 due to concerns regarding its toxicity, in many cases FTD has been excessively and/or illegally applied in productive animals in developing countries, because of its high efficacy and low-cost. Unlike other nitrofuran compounds, the hydrolytic and photolytic behavior of FTD in natural aquatic systems has not been thoroughly investigated. To this end, hydrolysis in different pH values and photolysis in aquatic environment, including lake, river and sea water have been both examined. Hydrolysis was found to have an insignificant impact on degradation of FTD in the aquatic environment relevant pH values, whereas indirect photolysis proved to be the main route of its elimination. The identification of tentative photoproducts (PPs) was performed using ultra high performance liquid chromatography coupled to hybrid LTQ/Orbitrap high resolution mass spectrometry. A possible pathway for photolytic transformation of FTD was proposed. Additionally, in silico simulations were used to evaluate the toxicity such as the mutagenicity of FTD and PPs. Complementary to the low-cost and time-limited simulations, an in vitro method (Vibrio Fischeri bioluminescence) was also used to assess ecotoxicity.

Integration of LC-LTQ-Orbitrap-MS and Network Pharmacology to Analyze the Active Components of Sijunzi Decoction and their Mechanism of Action Against Cytotoxicity-associated Premature Ovarian Insufficiency.

INTRODUCTION: Sijunzi Decoction (SJZD) is a classical prescription in traditional Chinese medicine that enhances neuroimmune endocrine function to alleviate inflammatory aging, a key pathogenic mechanism underlying premature ovarian insufficiency (POI). However, the mechanism through which SJZD alleviates POI remains unknown. Hence, we aimed to identify the active components of SJZD and its mechanism of therapeutic action against POI. METHODS: We identified compounds in SJZD using liquid chromatography-linear trap quadrupole- Orbitrap-mass spectrometry (LC-LTQ-Orbitrap-MS). Traditional Chinese Medicine Systems (TCMSP) and HERB databases were used to identify the ingredients and potential targets of SJZD. We analyzed Gene Ontology (GO) terms and enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways using RStudio and constructed a visual network using Cytoscape3.9.1. RESULTS: We identified 98 compounds using LC-LTQ-Orbitrap-MS, among which 29 were bioactive. The screen outputted yielded 151 predicted targets of these compounds that were associated with POI. The results of the GO and KEGG analyses showed that these compounds play key roles in cell growth, division, migration, and survival signaling pathways. Therefore, phosphatidylinositol 3-kinase (PI3K)/AKT, mitogen-activated protein kinase (MAPK), and epidermal growth factor receptor (EGFR) pathways might be closely associated with the pharmacological effects of SJZD on the pathological processes of POI. CONCLUSION: Our findings provide a scientific basis for rapidly analyzing bioactive compounds in SJZD and their pharmacological mechanisms.

A Targeted Approach by High Resolution Mass Spectrometry to Reveal New Compounds in Raisins.

Raisins are dried grapes mostly obtained from cultivars of Vitis vinifera L. and are extensively consumed worldwide. They are rich in bioactive compounds such as polyphenols, which are associated with a broad range of health benefits. The aim of the present study was to compare the phenolic profiles of three different raisin varieties (Thompson seedless, Muscat, and sultanas). Total polyphenols (TPs) were evaluated by the Folin-Ciocalteu (F-C) assay and significant differences were observed among all raisin varieties. Furthermore, liquid chromatography coupled with electrospray ionization hybrid linear ion trap quadrupole-Orbitrap-mass spectrometry (LC/ESI-LTQ-Orbitrap-MS) was employed for the comprehensive identification of phenolic constituents. A total of 45 compounds were identified, including hydroxybenzoic and hydroxycinnamic acids, flavanoids, flavonoids, flavonols, flavones, and stilbenoids. The three varieties of raisins showed a similar phenolic profile, although the highest number of phenolic compounds was identified in Muscat raisins owing to the proanthocyanidins extracted from their seeds, while stilbenoids were not detected in the Thompson variety.

Phenolic Profile of Grape Canes: Novel Compounds Identified by LC-ESI-LTQ-Orbitrap-MS.

Grape canes (Vitis vinifera L.) are a viticulture industry by-product with an important content of secondary metabolites, mainly polyphenols with a broad spectrum of demonstrated health benefits. Grape canes, therefore, have considerable economic potential as a source of high-value phytochemicals. In this work, liquid chromatography coupled with electrospray ionization hybrid linear trap quadrupole-Orbitrap mass spectrometry (LC-LTQ-Orbitrap) was used for the comprehensive identification of polyphenolic compounds in grape canes. Identification of polyphenols was performed by comparing their retention times, accurate mass measured, and mass fragmentation patterns with those of reference substances or available data in the literature. A total of 75 compounds were identified, including phenolic acids, flavanols, flavonols, flavanonols, flavanones, and stilbenoids. The most abundant polyphenols were proanthocyanidins and stilbenoids and their oligomers. Moreover, the high-resolution mass spectrometry analysis revealed the occurrence of 17 polyphenols never described before in grape canes, thereby providing a more complete polyphenolic profile of this potentially valuable by-product.

Novel Neuroprotective Lead Compound Ligustrazine Derivative Mass Spectrometry Fragmentation Rule and Metabolites in Rats by LC/LTQ-Orbitrap MS.

The neuroprotective evaluation of ligustrazine derivatives has become a research focus all over the world. A novel ligustrazine derivative, (3,5,6-Trimethylpyrazin-2-yl)methyl(E)-3-(4-((3,5,6-trimethylpyrazin-2-l)methoxy)phenyl)acrylate (T-CA), has shown protective effects against CoCl2-induced neurotoxicity in a differentiated PC12 cell model and middle cerebral artery occlusion (MCAO) model in our previous studies. However, nearly none of the parent drugs existed after rapid metabolism due to uncertain reasons. Thus, the fragmentation regularities of mass spectra, and metabolites, of T-CA in rats were examined using liquid chromatography-electrospray ionizationion trap mass spectrometry (LC/LTQ-Orbitrap MS) in this research. The main fragment ion, mass spectrum characteristics, and the structural information were elucidated. When compared with a blank sample, we identified five kinds of T-CA metabolites, including three phase I metabolites and two phase II metabolites. The results showed that the metabolic pathways of T-CA in rats via oral administration were hydrolysis (ether bond rupture, ester bond rupture), oxidation, reduction, glucose aldehyde acidification, etc. In addition, three main metabolites were synthesized and their structures were identified by superconducting high-resolution NMR and high-resolution mass spectroscopy (HR-MS). The neuroprotective activity of these metabolites was validated in a PC12 cell model. One of the metabolites (M2) showed significant activity (EC50 = 9.67 µM), which was comparable to the prototype drug T-CA (EC50 = 7.97 µM). The current study provides important information for ligustrazine derivatives, pertaining to the biological conversion process in vivo.

[Identification of alkaloids and flavonoids in all parts of Fritillaria thunbergii using LC-LTQ-Orbitrap MSn].

Alkaloids and flavonoids in flowers, flower buds, stems, leaves, and bulbs of Fritillaria thunbergii were identified by LC-LTQ-Orbitrap MSn.Alkaloids were identified by ACQUITY UPLC BEH C18（2.1 mm×50 mm, 1.7 µm ) chromatographic column with a mobile phase of 10 mmol•L⁻¹ ammonium formate-acetonitrile and gradient elution in positive MS scan mode.Meanwhile, flavonoids were analyzed by Agilent-Zorbax SB C18 (4.6 mm×250 mm, 5 µm) chromatographic column with a mobile phase of 0.2% acetic acid-acetonitrile and gradient elution in negative MS scan mode.Combined with literature reports, chemical constituents were identified and determined by accurate molecular weights and fragment ion peaks in the ESI-MS/MS spectra based on high resolution mass spectrometer.In all parts of F.thunbergii, 37 alkaloids including 7 alkaloids (zhebeininoside, peimisine, peimine, peiminine, ebeiedinone/puqiedinone, ebeiedine/ puqiedine, peimisine-N-oxide) were simultaneously analyzed.Moreover, 16 flavonoids including quercetin, kaempferol and their glycosides were identified.The results indicated that the aerial parts had the similar alkaloids as the bulbs on the whole.Meanwhile, it had a series of flavonoids undetected in the bulbs.Our results provided the scientific basis for the development and utilization of aerial parts of F.thunbergii.

[LC-LTQ-Orbitrap analysis on chemical constituents in Scrophulariae Radix extract and their metabolites in rat plasma].

Chemical constituents in extract of Scrophulariae Radix and their metabolites in rat plasma after oral administration were identified by HPLC-LTQ-Orbitrap. Samples were separated by a Venusil MP C18 column using a binary gradient elution. The information on the total ion chromatogram, the extraction chromatogram and the mass spectrogram in a negative mode were synthetically analyzed by comparing the retention time, MS and MS/MS spectra with literature data and some of reference standards to conduct a qualitative study on constituents of Radix Scrophulariae extract in vivo and in vitro. Totally 37 compounds from Scrophularia ningpoensis extract were detected including 12 iridoid glycosides, 20 phenylpropanoids and 5 unknown compounds. In vivo, harpagide, harpagoside and angoroside C were confirmed to enter into the blood in prototype forms. Besides, another 2 prototype compounds and 2 metabolites were detected in rat plasma after oral administration of S. ningpoensis extract. The results are beneficial for the determination of bioactive substances of S. ningpoensis and significant for further studies on S. ningpoensis.

Identification of alkaloids and flavonoids in all parts of Fritillaria thunbergii using LC-LTQ-Orbitrap MSn / 中国中药杂志

Alkaloids and flavonoids in flowers, flower buds, stems, leaves, and bulbs of Fritillaria thunbergii were identified by LC-LTQ-Orbitrap MSn.Alkaloids were identified by ACQUITY UPLC BEH C₁₈（2.1 mm×50 mm, 1.7 μm ) chromatographic column with a mobile phase of 10 mmol•L⁻¹ ammonium formate-acetonitrile and gradient elution in positive MS scan mode.Meanwhile, flavonoids were analyzed by Agilent-Zorbax SB C₁₈ (4.6 mm×250 mm, 5 μm) chromatographic column with a mobile phase of 0.2% acetic acid-acetonitrile and gradient elution in negative MS scan mode.Combined with literature reports, chemical constituents were identified and determined by accurate molecular weights and fragment ion peaks in the ESI-MS/MS spectra based on high resolution mass spectrometer.In all parts of F.thunbergii, 37 alkaloids including 7 alkaloids (zhebeininoside, peimisine, peimine, peiminine, ebeiedinone/puqiedinone, ebeiedine/ puqiedine, peimisine-N-oxide) were simultaneously analyzed.Moreover, 16 flavonoids including quercetin, kaempferol and their glycosides were identified.The results indicated that the aerial parts had the similar alkaloids as the bulbs on the whole.Meanwhile, it had a series of flavonoids undetected in the bulbs.Our results provided the scientific basis for the development and utilization of aerial parts of F.thunbergii.

LC-LTQ-Orbitrap analysis on chemical constituents in Scrophulariae Radix extract and their metabolites in rat plasma / 中国中药杂志

Chemical constituents in extract of Scrophulariae Radix and their metabolites in rat plasma after oral administration were identified by HPLC-LTQ-Orbitrap. Samples were separated by a Venusil MP C₁₈ column using a binary gradient elution. The information on the total ion chromatogram, the extraction chromatogram and the mass spectrogram in a negative mode were synthetically analyzed by comparing the retention time, MS and MS/MS spectra with literature data and some of reference standards to conduct a qualitative study on constituents of Radix Scrophulariae extract in vivo and in vitro. Totally 37 compounds from Scrophularia ningpoensis extract were detected including 12 iridoid glycosides, 20 phenylpropanoids and 5 unknown compounds. In vivo, harpagide, harpagoside and angoroside C were confirmed to enter into the blood in prototype forms. Besides, another 2 prototype compounds and 2 metabolites were detected in rat plasma after oral administration of S. ningpoensis extract. The results are beneficial for the determination of bioactive substances of S. ningpoensis and significant for further studies on S. ningpoensis.

In vitro and in vivo identification of metabolites of magnoflorine by LC LTQ-Orbitrap MS and its potential pharmacokinetic interaction in Coptidis Rhizoma decoction in rat.

Magnoflorine, an important aporphine alkaloid in Coptidis Rhizoma, is increasingly attracting research attention because of its pharmacological activities. The in vivo and in vitro metabolism of magnoflorine was investigated by LC LTQ-Orbitrap MS. In vivo samples including rat urine, feces, plasma and bile were collected separately after both oral (50 mg kg(-1) ) and intravenous administration (10 mg kg(-1) ) of magnoflorine, along with in vitro samples prepared by incubating magnoflorine with rat intestinal flora and liver microsome. As a result, 12 metabolites were found in biological samples. Phase I metabolites were identified in all biological samples, while phase II metabolites were mainly detected in urine, plasma and bile. In a pharmacokinetic study, rats were not only dosed with magnoflorine via oral (15, 30 and 60 mg kg(-1) ) and intravenous administration (10 mg kg(-1) ) but also dosed with Coptidis Rhizoma decoction (equivalent to 30 mg kg(-1) of magnoflorine) by intragastric administration to investigate the interaction of magnoflorine with the rest of compounds in Coptidis Rhizoma. Studies showed that magnoflorine possessed lower bioavailability and faster absorption and elimination. However, pharmacokinetic parameters altered significantly (p < 0.05) when magnoflorine was administered in Coptidis Rhizoma decoction. Oral gavage of Coptidis Rhizoma decoction decreased the absorption and elimination rates of magnoflorine, which revealed that there existed pharmacokinetic interactions between magnoflorine and the rest of ingredients in Coptidis Rhizoma.

High resolution mass spectrometry in the identification of transformation products and metabolites from ß-lactam antibiotics in thermally treated milk.

Antibiotics such as ß-lactam derivatives (penicillins and cephalosporins) are frequently used in veterinary medicine. The presence of these antibiotics together with their metabolites and/or products produced in subsequent treatments at which milk is submitted (sterilization, pasteurization), may be responsible for bacterial resistance, allergy and/or toxicity on sensitive individuals. In this study, liquid chromatography coupled with high resolution mass spectrometry (LC-HRMS) is used to identify transformation products (TPs) from four ß-lactam antibiotics (amoxicillin (AMOX), cephapirin (PIR), ceftiofur (TIO) and penicillin G (PENG)) in thermally treated cow milk. In addition, milk from cows medicated with PENG has also been analogously treated and studied. The detected TPs come mainly from hydrolysis and decarboxylation reactions. Products more strongly degraded respect to parent compounds (of lower molecular weight) were obtained after treating milk at higher temperatures. Products identified in milk from cows medicated with PENG have been classified as TPs when coming from chemical/thermal degradation, and metabolites when resulting from the biological drug metabolism. While TPs are the result of hydrolysis and decarboxylation processes, as already indicated, an enzymatic conjugation with amino acids is suggested to be involved in the formation of metabolites.

High-performance liquid chromatography LTQ-Orbitrap mass spectrometry method for tomatidine and non-target metabolites quantification in organic and normal tomatoes.

Tomatoes, members of the Solanaceae plant family, produce biologically active secondary metabolites, including glycoalkaloids and aglycons, which may have both adverse and beneficial biological effects. A new liquid chromatography method that utilized LTQ-Orbitrap MS was developed for the analysis of tomatidine, the main aglycon in tomatoes. Recoveries of tomatidine were >98.3% with the relative standard deviations (RSDs) below 6.1%. The limit of detection (LODs) was 0.0003 mg kg(-1). The limit of quantitation (LOQs) is 0.001 mg kg(-1). The linear range was between with 0.0025 and 1 mg kg(-1) with an excellent correlation coefficient (R(2)) equal to 0.9990. Various tomato samples were analyzed and the level of tomatidine in the 11 samples analysed was higher in normal respect to organic tomatoes. The capability of the set-up Full Scan LTQ-Orbitrap MS method allowed us to quantified two non-target analytes. The m/z 1032 was identified as dehydrotomatine, confirmed through accurate mass studies (mass error in ppm equal to 1.5017) meanwhile m/z 902 as (Glc)2-Gal-Tomatidine (ß1-Tomatine) (mass error in ppm equal to 2.0719).

Identification and elucidation of the structure of in vivo metabolites of diaveridine in chicken.

Diaveridine (DVD) is a popular antibacterial synergist that is widely used in combination with sulfonamide. It has been reported to be genotoxic to mammalian cells, but more studies are required to clarify this. Moreover, there is very little information on its pharmacokinetics, metabolic elimination and mechanism of toxicity. Therefore, in order to gain a better understanding of the metabolism of DVD, we performed high-performance liquid chromatography linear ion trapped orbitrap mass spectrometer (LC-LTQ-Orbitrap). With this approach, we identified 15 metabolites of DVD in chicken after a single oral administration of DVD; 10 of these metabolites have been identified in vivo for the first time. Nine phase I and five phase II metabolites were detected in the plasma, and eight phase I and six phase II metabolites were found in feces. The major phase I metabolites were formed via the O-demethylation and N-oxidation pathways, and the major phase II metabolites were glucuronide conjugates. These results are essential for understanding this compound more clearly and lay the basis for further studies about the metabolism of DVD. Therefore, using this approach, we were able to identify and characterize metabolites of DVD with high sensitivity and resolution. We were able to detect a broad range of metabolites, even some trace ones and some so far unknown metabolites.

Screening of synthetic PDE-5 inhibitors and their analogues as adulterants: analytical techniques and challenges.

The popularity of phosphodiesterase type 5 (PDE-5) enzyme inhibitors for the treatment of erectile dysfunction has led to the increase in prevalence of illicit sexual performance enhancement products. PDE-5 inhibitors, namely sildenafil, tadalafil and vardenafil, and their unapproved designer analogues are being increasingly used as adulterants in the herbal products and health supplements marketed for sexual performance enhancement. To date, more than 50 unapproved analogues of prescription PDE-5 inhibitors were found as adulterants in the literature. To avoid detection of such adulteration by standard screening protocols, the perpetrators of such illegal products are investing time and resources to synthesize exotic analogues and devise novel means for adulteration. A comprehensive review of conventional and advance analytical techniques to detect and characterize the adulterants is presented. The rapid identification and structural elucidation of unknown analogues as adulterants is greatly enhanced by the wide myriad of analytical techniques employed, including high performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), liquid chromatography mass-spectrometry (LC-MS), nuclear magnetic resonance (NMR) spectroscopy, vibrational spectroscopy, liquid chromatography-Fourier transform ion cyclotron resonance-mass spectrometry (LC-FT-ICR-MS), liquid chromatograph-hybrid triple quadrupole linear ion trap mass spectrometer with information dependent acquisition, ultra high performance liquid chromatography-time of flight-mass spectrometry (UHPLC-TOF-MS), ion mobility spectroscopy (IMS) and immunoassay methods. The many challenges in detecting and characterizing such adulterants, and the need for concerted effort to curb adulteration in order to safe guard public safety and interest are discussed.