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Highlights • Comprehensive multiresidue analysis of pesticides in grapevine leaf matrix. • The scope of the method also covers plant growth regulators. • A high throughput QuEChERS-based workflow is optimized for sample preparation. • The GC–MS/MS and LC–MS/MS method performance are demonstrated at ≥0.01 mg/kg. • The method performance complied with the SANTE/11813/2017 guidelines and EU-MRLs. Abstract Grape leaf, which is known for its nutritional and medicinal properties, is finding increased applications for cuisine and remedial purposes. This article reports a comprehensive analytical method for the identification and quantification of a broad range of pesticides and plant growth regulators (PGRs) in the grape leaf matrix. The sample preparation method for pesticides involved an optimized QuEChERS-based extraction protocol, with subsequent clean-up by the dispersive solid phase extraction (dSPE) using a mixture of sorbents (25 mg PSA + 5 mg GCB + 150 mg MgSO 4). The PGRs were extracted with methanol. The performance of the method was investigated and validated for a mixture of 363 pesticides (148 in GC–MS/MS and 203 in LC–MS/MS) and 12 PGRs (LC–MS/MS) in compliance with the analytical quality control criteria of the SANTE/11813/2017 guidelines. The matrix effects were comparatively higher against grape berries. The findings indicated satisfactory recoveries at 10 ng/g and higher levels with precision RSDs less than 20%. This method has potential applications in commercial residue testing laboratories and also for the regulatory compliance check purposes for its lower LOQs compared to the corresponding EU-MRLs. [ABSTRACT FROM AUTHOR]

Tuber crops substantially contribute to the food security in the developing countries. Often, their cultivation involves unregulated applications of pesticides, leading to MRL non-compliances. Despite their rising currency in international trade, there exist scarcely any methods for pesticide residue analysis in these matrices. Therefore, we developed a multi-residue method for simultaneous analysis of a diverse range of pesticides in tuber crops, based on pressurized liquid extraction by ethyl acetate, followed by selective identification and quantification of the residues using GC–MS selected reaction monitoring. The method was evaluated for 150 pesticides. Results showed that their limits of quantification were 0.1–10 ng/g, with recoveries of 70–120%. When compared to the conventional analytical techniques, such as QuEChERS and buffered ethyl acetate extraction, this method provided superior performance in terms of precision, and recovery of the spiked and incurred residues with similar productivity. The method holds promise for commercial and regulatory residue analysis. [ABSTRACT FROM AUTHOR]

A novel screening and quantitation method is reported for non-target multiresidue analysis of pesticides using ultra-HPLC-quadrupole-Orbitrap mass spectrometry in spice matrices, including black pepper, cardamom, chili, coriander, cumin, and turmeric. The method involved sequential full-scan (resolution = 70,000), and variable data independent acquisition (vDIA) with nine consecutive fragmentation events (resolution = 17,500). Samples were extracted by the QuEChERS method. The introduction of an SPE-based clean-up step through hydrophilic-lipophilic-balance (HLB) cartridges proved advantageous in minimizing the false negatives. For coriander, cumin, chili, and cardamom, the screening detection limit was largely at 2 ng/g, while it was 5 ng/g for black pepper, and turmeric. When the method was quantitatively validated for 199 pesticides, the limit of quantification (LOQ) was mostly at 10 ng/g (excluding black pepper, and turmeric with LOQ = 20 ng/g) with recoveries within 70–120%, and precision-RSDs <20%. Furthermore, the method allowed the identification of suspected non-target analytes through retrospective search of the accurate mass of the compound-specific precursor and product ions. Compared to LC–MS/MS, the quantitative performance of this Orbitrap-MS method had agreements in residue values between 78–100%. [ABSTRACT FROM AUTHOR]

Public exposure to pesticide residues through the main/side-stream smoke of tobacco ( Nicotiana tabacum L.) is an international concern. This article reports optimization and validation of large-scale multiresidue analysis methods involving low pressure and traditional gas chromatography tandem mass spectrometry in compliance with the guidance residue levels (GRLs) of Cooperative Centre for Scientific Research Relative to Tobacco (CORESTA). Analysis by low pressure GC–MS/MS offered three times rapid turn around time over the traditional GC–MS/MS with limits of quantifications (LOQs) less than 2 μg/L for all the 259 test compounds and the recoveries in the range of 70–118% (±20%) at 10 and 20 μg/kg levels of fortification. [ABSTRACT FROM AUTHOR]

Highlights: [•] An effective multiresidue analysis method reported for 47 pesticides in tobacco. [•] Resolved analytes from co-eluted matrix by multi-dimensional GC heart-cut. [•] Analysis by GC-MS/SIM with an output of 27 samples/person/day. [Copyright &y& Elsevier]

Highlights: [•] Determination of 341 pesticides in fruits and vegetables using USRM. [•] Reduction in matrix effect and improvement in accuracy at higher resolutions. [•] Quantitation enhanced data dependent scan for confirmation of trace residues. [Copyright &y& Elsevier]

Abstract: The waste disposal practices on land frequently lead to the deposition of hazardous waste at geologically/hydrogeologically unsuitable locations, resulting in surface and groundwater contamination. The movement of chemicals through soil is not only dependent on the physical, chemical and biological properties of the waste but also on the characteristics of the soil of the disposal site. In this paper the authors report their results on the influence of soil components on adsorption–desorption of certain industrially widely used hazardous organics like phenol, p-nitrophenol, 4-chloro-2-nitrophenol and 2,4-dichlorophenol on typical soils of Patancheru industrial area (Hyderabad, AP, India). The data on nature of organics, soil organic matters, clay, free iron and aluminum oxides of soils are known to influence the adsorption–desorption process are presented. There was reduction up to 67.5% (organic matter removed), 53.8% (clay removed) and 24.2% (iron and aluminum oxides removed) in the adsorption capacity of the soils when compared to untreated soils indicating the role played by these soil components in adsorption process. Desorption isotherms of soil adsorbed hazardous organics exhibited hysteresis at higher initial concentration indicating the degree of irreversibility of adsorption–desorption process. Mixed microbial cultures were developed which can degrade the hazardous organics to complete mineralisation by utilizing them as sole source of carbon and their corresponding biokinetic constants were evaluated. Preparation of dumpsites with suitable soil surface having high holding capacity for organics and their in situ biodegradation by mixing with specific microbial cultures can be exploited as a cost effective technology for reclamation of hazardous waste dumpsites. [Copyright &y& Elsevier]

• First comprehensive screening & quantitation study on pesticide residues in tobacco matrix. • Non-target screening of pesticide residues by HPLC-quadrupole-orbitrap mass spectrometry. • Variable data independent acquisition offered accurate mass based screening & quantitation. • Isomeric & isobaric compounds differentiated based on LC separation & unique product ions. • Screening Detection Limits & LOQs in line with the current Guidance Residue Levels. Public exposure to pesticides through tobacco has attracted serious attention. Here we report a simultaneous screening and quantitation method for the non-target multiresidue analysis of pesticides in different tobacco types. The method involved extraction of a homogenate (20 g, containing 2 g tobacco) in ethyl acetate (10 mL), cleanup of 2 mL extract by dispersive solid phase extraction with PSA (50 mg)+C 18 (50 mg)+GCB (25 mg)+MgSO 4 (100 mg), followed by reconstitution in 1 mL acetonitrile:water (3:7) and analysis using HPLC with Quadrupole-Orbitrap mass spectrometry. The high resolution accurate mass analysis was performed through sequential full-scan (resolution=35000) and variable data independent acquisition (resolution=17500) events. When the method was evaluated in a mixture of 181 pesticides, it effectively minimised matrix interferences and false negatives. The target compounds included 5 pairs of isomers and 27 pairs of isobars, which were distinguished based on chromatographic separation, mass resolving power and/or unique product ions. The screening detection limit (SDL) for 86.4% of the test pesticides was set at 5 ng/g, while the remainder had the SDLs at 10 ng/g (9.3%) and 40 ng/g (4.3%). Nearly, 75% of the compounds showed recoveries of 70–120% at 10 ng/g. The rest of the compounds showed satisfactory recoveries at 40 and 100 ng/g. In all cases, precision-RSDs were < 20%. The established method demonstrated a successful performance in four different types of tobacco matrices while aligning with the guidelines of SANTE and US-FDA. Owing to its efficiency, the method is recommended for screening and quantitation of multiclass pesticides in tobacco. [ABSTRACT FROM AUTHOR]

• For the first time, an LC-ESI-MS/MS method is reported for captan, captafol, folpet & iprodione. • The scope of the method also includes degradation products of captan and folpet. • Samples were cryogenically comminuted & extracted with acidified ethyl acetate or acetonitrile. • Limits of quantification were ≤0.01 mg/kg for all these pesticides in fruits and vegetables. • This method provides a viable alternative to conventional GC–MS/MS methods with improved precision & accuracy. An improved liquid chromatography tandem mass spectrometry method is reported for the determination of residues of captan (+tetrahydrophthalimide), captafol, folpet (+phthalimide), and iprodione in fruits and vegetables. The optimized electrospray ionization parameters (high cone gas flow, and a low desolvation temperature) did not result in degradation of target compounds, rather they provided a significant advantage over the conventional GC–MS/MS methods, which lack sensitivity and repeatability. Strategies for minimizing losses in recovery of these compounds during sample preparation included cryogenic comminution, extraction with acidified ethyl acetate or acetonitrile, and dilution of the final extract with acidified water prior to LC-MS/MS analysis. The method performance complied with the SANTE/11813/2017 guidelines, with recoveries in the range of 70–120% at the LOQ of 0.01 mg/kg across the tested matrices at various pHs. The efficiency of the method was reflected in its precision (RSDs < 10%) for incurred residues. [ABSTRACT FROM AUTHOR]

Tinospora cordifolia herbal supplements have recently gained prominence due to their promising immunomodulatory and anti-viral effects against SARS-CoV-2. Mislabelling or diluting Tinospora supplements for profit may harm public health. Thus, validating the label claim of these supplements in markets is critical. This study investigated how high resolution mass spectrometry-based metabolomics and chemometrics can be used to distinguish Tinospora cordifolia from two other closely related species (T. crispa and T. sinensis). The Orthogonal Partial Least Square Discriminant Analysis (OPLS-DA) and PLS-DA based chemometric models predicted the species identity of Tinospora with 94.44% accuracy. These classification models were trained using 54 T. cordifolia , 21 T. crispa , and 21 T. sinensis samples. We identified 7 biomarkers, including corydine, malabarolide, ecdysterone, and reticuline, which discriminated Tinospora cordifolia from the two other species. The label claim of 25 commercial Tinospora samples collected from different parts of India was verified based on the relative abundance of the biomarker compounds, of which 20 were found authentic. The relative abundance of biomarkers significantly varied in the 5 suspicious market samples. This pilot study demonstrates a robust metabolomic approach for authenticating Tinospora species, which can further be used in other herbal matrices for product authentication and securing quality. [Display omitted] • HRMS-based metabolomic fingerprinting for species authentication in herbal supplements of Tinospora cordifolia. • Metabolites were identified using comprehensive custom curated accurate mass library. • Chemometric models were developed as proof of concept for authenticating Tinospora cordifolia herbal supplements. • Biomarkers were identified and their relative abundance were compared in authentic and adulterated samples. • This study could help in developing a rugged method for regulatory control of quality and authenticity of herbal supplements. [ABSTRACT FROM AUTHOR]

Abstract: The feasibility of a pinhole camera system for online dosimetry in boron neutron capture therapy (BNCT) was studied. A prototype system was designed and built. Prompt γ-rays from the 10B(n,α)7Li reaction from a phantom irradiated with neutrons were detected with the prototype system. An image was reconstructed from the experimental data. The reconstructed image showed a good separation of the two borated regions in the phantom. The counting rates and signal-to-noise ratio when using the system in actual BNCT applications are also discussed. [Copyright &y& Elsevier]

• The terpene cyclase gene responsible for the biosynthesis of heptelidic acid in Trichoderma virens has been identified. • Heptelidic acid biosynthesis involves a terpene cyclase and three cytochrome P450s located in two different clusters. • Heptelidic acid biosynthesis is regulated by a GAPDH which is tolerant to this metabolite. • Biosynthesis of other non-volatile metabolites like viridin and gliovirin is regulated by heptelidic acid. Trichoderma virens produces viridin/viridiol, heptelidic (koningic) acid, several volatile sesquiterpenes and gliotoxin (Q strains) or gliovirin (P strains). We earlier reported that deletion of the terpene cyclase vir4 and a glyceraldehyde-3-phosphate dehydrogenase (GAPDH, designated as vGPD) associated with the " vir " cluster abrogated the biosynthesis of several volatile sesquiterpene metabolites. Here we show that, the deletion of this GAPDH also impairs the biosynthesis of heptelidic acid (a non-volatile sesquiterpene), viridin (steroid) and gliovirin (non-ribosomal peptide), indicating regulation of non-volatile metabolite biosynthesis by this GAPDH that is associated with a secondary metabolism gene cluster. To gain further insights into the details of this novel form of regulation, we identified the terpene cyclase gene responsible for heptelidic acid biosynthesis (hereafter designated as has1) and prove that the expression of this gene is regulated by vGPD. Interestingly, deletion of has1 impaired biosynthesis of heptelidic acid (HA), viridin and gliovirin, but not of volatile sesquiterpenes. Deletion of the vir cluster associated terpene cyclase gene (vir4), located next to the vGPD gene, did not impair biosynthesis of HA, viridin or gliovirin. We thus unveil a novel circuitry of regulation of secondary metabolism where an HA-tolerant GAPDH isoform (vGPD) regulates HA biosynthesis through the transcriptional regulation of the HA-synthase gene (which is not part of the " vir " cluster). Interestingly, impairment of HA biosynthesis leads to the down-regulation of biosynthesis of other non-volatile secondary metabolites, but not of volatile secondary metabolites. We thus provide evidence that the " vir " cluster associated, HA-tolerant GAPDH in T. virens participates in the biosynthesis of volatile sesquiterpenes as a biosynthetic enzyme, and regulates the production of non-volatile metabolites via regulation of HA biosynthesis. The orthologue of the " vir " cluster in Aspergillus oryzae was earlier reported to synthesize HA by another group. Our study thus proves that the same gene cluster can code for unrelated metabolites in different species. [ABSTRACT FROM AUTHOR]

For the first time, jute activated carbon (JAC), a byproduct of the jute industry, was characterised and evaluated for its cleanup efficiency in a mixture of 181 multiclass pesticide residue testing using gas chromatography tandem mass spectrometry (GC-MS/MS). Four commercially-important food matrices including okra, spinach, pomegranate and tea were chosen. Various physico-chemical techniques were used to characterise the material. The cleanup method involved dispersive solid phase extraction (dSPE) using a combination of JAC (5 mg) with 25 mg of primary secondary amine per mL of the sample extract (in ethyl acetate). The findings demonstrated a lower matrix effect and higher signal-to-noise ratio were recorded for JAC. Overall, the method offered satisfactory recoveries for most of the pesticides in all the tested matrices. The cleanup effectiveness of JAC showed superiority over the commercially available, non-renewable dSPE sorbent viz. graphitised carbon black (GCB). With a production cost of only US Dollar ~10/kg, JAC is a low-cost alternative to commercial GCB (cost = US Dollar 11–12/g). The study valorises the potential of JAC and anticipates its large-scale application in food testing laboratories. • Jute activated carbon (JAC) as a cleanup agent in pesticide residue analysis. • JAC provided efficient cleanup in okra, spinach, pomegranate and tea. • The GC-MS/MS method performance was satisfactory for multiclass pesticides. • JAC is a cost-effective alternative of commercially available carbon sorbents. [ABSTRACT FROM AUTHOR]