Trivalent Copper Ion-Mediated Dual Oxidation in the Copper-Catalyzed Fenton-Like System in the Presence of Histidine.

The Cu(II)/H2O2 system is recognized for its potential to degrade recalcitrant organic contaminants and inactivate microorganisms in wastewater. We investigated its unique dual oxidation strategy involving the selective oxidation of copper-complexing ligands and enhanced oxidation of nonchelated organic compounds. L-Histidine (His) and benzoic acid (BA) served as model compounds for basic biomolecular ligands and recalcitrant organic contaminants, respectively. In the presence of both His and BA, the Cu(II)/H2O2 system rapidly degraded His complexed with copper ions within 30 s; however, BA degraded gradually with a 2.3-fold efficiency compared with that in the absence of His. The primary oxidant responsible was the trivalent copper ion [Cu(III)], not hydroxyl radical (•OH), as evidenced by •OH scavenging, hydroxylated BA isomer comparison with UV/H2O2 (a •OH generating system), electron paramagnetic resonance, and colorimetric Cu(III) detection via periodate complexation. Cu(III) selectively oxidized His owing to its strong chelation with copper ions, even in the presence of excess tert-butyl alcohol. This selectivity extended to other copper-complexing ligands, including L-asparagine and L-aspartic acid. The presence of His facilitated H2O2-mediated Cu(II) reduction and increased Cu(III) production, thereby enhancing the degradation of BA and pharmaceuticals. Thus, the Cu(II)/H2O2 system is a promising option for dual-target oxidation in diverse applications.

Adsorption simulation of 2,4-D pesticide on novel zinc-based 2-amino-4-(1H-1,2,4-triazole-4-yl)benzoic acid coordination complexes using machine learning approach.

The capacity of zinc-based 2-amino-4-(1H-1,2,4-triazole-4-yl)benzoic acid coordination complex (Zn(NH2-TBA)2) and modified Zn(NH-TBA)2COMe complex for removal of 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous solutions was investigated through adsorption modeling and artificial intelligence tools. Analyzing the adsorption characteristics of pesticides helps in studying the groundwater pollution by pesticides in agriculture area.In this study, Zn(NH2-TBA)2 was synthesized using Schiff base and its surface was modified using acetic anhydride group and their physical characteristics were identified using proton NMR, FTIR, and XRD. NMR results showed maximum modification yield obtained was 65% after 5 days. The porous structure and surface area monitored using nitrogen isotherm and BET surface area analysis presented relatively less surface area and porosity after modification. Adsorption modelling indicated that Toth model with a maximum adsorption capacity of 150.8 mg/g and 100.7 mg/g represents the homogenous adsorption systems which satisfy both low- and high-end boundary of adsorbate concentration in all settings according to the optimum point, while the kinetics and rate of 2,4-D adsorption follow the pseudo-first-order kinetic model in all situations. Artificial neural network (ANN), support vector regression, and particle swarm optimized least squares-support vector regression (PSO-LSSVR) were used for the optimization and modelling of adsorbent mass, adsorbate concentration, contact time, and temperature to develop predictive equations for the simulation of the adsorption efficiency of 2,4-D pesticide. The obtained results exhibited the better performance of ANN and PSO-LSSVR for prediction of adsorption results. The mean square error values of ANN (0.001, 0.012) and PSO-LSSVR (0.121, 0.105) were obtained for Zn(NH2-TBA)2 and Zn(NH-TBA)2COMe, respectively, while their respective coefficient of determination (R2) obtained were 0.999 and 0.988 for ANN and 0.980 and 0.825 for PSO-LSSVR. The study specified that machine learning predictive behavior performed better for Zn(NH2-TBA)2 compared to Zn(NH-TBA)2COMe that is also supported by theoretical kinetics and isotherm models. The research concludes that artificial intelligence models are the most efficient tools for studying the predictive behavior of adsorption data.

Preparation and sustained-release of chitosan-alginate bilayer microcapsules containing aromatic compounds with different functional groups.

This study investigated the release of aromatic compounds with distinct functional groups within bilayer microcapsules. Bilayer microcapsules of four distinctive core materials (benzyl alcohol, eugenol, cinnamaldehyde, and benzoic acid) were synthesized via freeze-drying. Chitosan (CS) and sodium alginate (ALG) were used as wall materials. CS concentration, using orthogonal experiments with the loading ratio as a metric. Under optimal conditions, three other types of microcapsules (cinnamic aldehyde, benzoic acid, and benzyl alcohol) were obtained. The four types of microcapsules were characterized using Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscope (TEM), and thermogravimetric analysis (TGA), and their sustained release characteristics were evaluated. The optimal conditions were: CS dosage, 1.2 %; CS-to-eugenol mass ratio, 1:2; and CS-to-ALG mass ratio, 1:1. By comparing the IR spectra of the four types of microcapsules, wall material, and core material, the core materials were revealed to be encapsulated within the wall material. SEM results revealed that the granular protuberances on the surface of the microcapsules were closely aligned and persistent when magnified 2000×. The TEM results indicated that all four microcapsules had a spherical and bilayer structure. The thermal stability and sustained release results showed that the four microcapsules were more resilient and less volatile than the four core materials. The release conformed to first-order kinetics, and the release ratios of the four microcapsules were as follows: benzyl alcohol microcapsules Ëƒ eugenol microcapsules Ëƒ cinnamaldehyde microcapsules Ëƒ benzoic acid microcapsules. The prepared bilayer microcapsules encapsulated four different core materials with good sustained release properties.

Quantification of Free Radicals from Vaping Electronic Cigarettes Containing Nicotine Salt Solutions with Different Organic Acid Types and Concentrations.

Electronic (e-) cigarette formulations containing nicotine salts from a range of organic acid conjugates and pH values have dominated the commercial market. The acids in the nicotine salt formulations may alter the redox environment in e-cigarettes, impacting free radical formation in e-cigarette aerosol. Here, the generation of aerosol mass and free radicals from a fourth-generation e-cigarette device was evaluated at 2 wt % nicotine salts (pH 7, 30:70 mixture propylene glycol to vegetable glycerin) across eight organic acids used in e-liquids: benzoic acid (BA), salicylic acid (SLA), lactic acid (LA), levulinic acid (LVA), succinic acid (SA), malic acid (MA), tartaric acid (TA), and citric acid (CA). Furthermore, 2 wt % BA nicotine salts were studied at the following nicotine to acid ratios: 1:2 (pH 4), 1:1 (pH 7), and 2:1 (pH 8), in comparison with freebase nicotine (pH 10). Radical yields were quantified by spin-trapping and electron paramagnetic resonance (EPR) spectroscopy. The EPR spectra of free radicals in the nicotine salt aerosol matched those generated from the Fenton reaction, which are primarily hydroxyl (OH) radicals and other reactive oxygen species (ROS). Although the aerosol mass formation was not significantly different for most of the tested nicotine salts and acid concentrations, notable ROS yields were observed only from BA, CA, and TA under the study conditions. The e-liquids with SLA, LA, LVA, SA, and MA produced less ROS than the 2 wt % freebase nicotine e-liquid, suggesting that organic acids may play dual roles in the production and scavenging of ROS. For BA nicotine salts, it was found that the ROS yield increased with a higher acid concentration (or a lower nicotine to acid ratio). The observation that BA nicotine salts produce the highest ROS yield in aerosol generated from a fourth-generation vape device, which increases with acid concentration, has important implications for ROS-mediated health outcomes that may be relevant to consumers, manufacturers, and regulatory agencies.

Sorption behavior of three aromatic acids (benzoic acid, 1-naphthoic acid and 9-anthroic acid) on biochar: Cosolvent effect in different liquid phases.

Influence of the cosolvent on the sorption of organic acids on biochar has not been well understood. For this purpose, the sorption (log Km, L kg-1) of three aromatic acids (benzoic acid (BA, pKa = 4.20), 1-naphthoic acid (1-NAPA, pKa = 3.70), and 9-anthroic acid (9-ANTA, pKa = 3.65) was evaluated as a function of methanol volume fraction (fc = 0.0, 0.25, and 0.5), liquid pH (2.5 and 7.0), ionic composition (CaCl2 and KCl) and ionic strength (0.005 M, 0.5 M, and 1 M CaCl2). A giant Miscanthus-derived biochar (ZPC of 2.86) was used as the sorbent. For all solutes, the sorption coefficients (log Km) measured at pH 2.5 (i.e., pH < pKa) tended to decrease with increasing fc, as expected from the cosolvency model, while the result obtained at pH 7.0 was not fully explained by the same model. The log Km of 1-NAPA in the CaCl2 system was always greater than in the KCl system (p < 0.05) and the impact became pronounced at high pH (>pKa) with increasing fc. Increasing the Ca2+ concentration at fc = 0.0 (from 0.005 M to 1 M) enhanced the value by 0.32 log unit of Km. These phenomena indicate a significant role of dissolved Ca2+ in the liquid phase, most likely due to the formation of cation bridges between aromatic carboxylates and the biochar surface (i.e., [R-COO--Ca2+]-{Biochar-}). A decrease in the dielectric constant of the methanol mixture could fortify the formation of this bridge. Regardless of the degree of cosolvency power (σ), as the number of aromatic rings of solutes increases, Km decreases in the order BA > 1-NAPA > 9-ANTA, where fc = 0.0. In conclusion, the sorption potential of biochar can be significantly weakened by increasing pH and fc, and in the absence of a divalent cation.

Removal of BTEX from water system by synergistic flocculation of biosurfactant and iron salt.

The adsorption micelle flocculation (AMF) effect of biosurfactants (rhamnolipids, RL) and polymerized ferric sulfate (PFS) on the removal of low molecular weight benzoic acid (benzoic acid and p-methyl benzoic acid) and phenol (2,4-dichlorophenol and bisphenol A) organics was investigated. The coexistence system of RL and organic matter was constructed, and the effects of pH, Fe concentration, RL concentration and initial concentration of organic matter on the removal effect were discussed. For benzoic acid and p-methyl benzoic acid, the increase of Fe and RL concentrations was beneficial to their removal rates under weak acidic conditions, and the removal rate of the coexistence system was higher for methyl benzoic acid (87.7 %) than for benzoic acid (78.6 %), which might be attributed to the stronger hydrophobicity of the coexistence system for methyl benzoic acid; while for 2,4-dichlorophenol and bisphenol A, pH and Fe concentration changes had less effect on the removal rate, but the increase in RL concentration was favorable to the removal rate, which was 93.1 % and 86.7 % for BPA and 2,4-dichlorophenol, respectively. These findings provide feasible ideas and directions for the removal of organics by AMF using biosurfactants.

Oxyfunctionalization of Benzylic C-H Bonds of Toluene Mediated by Covalently Anchored Co-Schiff Bases.

Oxyfunctionalization of toluene to value-added benzaldehyde, benzyl alcohol and benzoic acid is of great significance. In this work, Co-Schiff bases were immobilized on commercial silica gel by covalent anchoring, and resulting catalysts were used to catalyze the oxidation of toluene in the presence of the cocatalyst N-hydroxyphthalimide (NHPI). The catalysts exhibited excellent textural and structural properties, reliable bonding and a predomination of the cobaltous ions. The catalyst synthesized by diethylamino salicylaldehyde (EASA) possessed a grafting density of 0.14 mmol/g and exhibited a toluene conversion of 37.5%, with predominant selectivities to benzaldehyde, benzyl alcohol and benzoic acid under solvent-free conditions. It is concluded that the effect of ligands on their catalytic performance might be related to their electron-donating or -withdrawing properties.

The Discovery of GSK3640254, a Next-Generation Inhibitor of HIV-1 Maturation.

GSK3640254 is an HIV-1 maturation inhibitor (MI) that exhibits significantly improved antiviral activity toward a range of clinically relevant polymorphic variants with reduced sensitivity toward the second-generation MI GSK3532795 (BMS-955176). The key structural difference between GSK3640254 and its predecessor is the replacement of the para-substituted benzoic acid moiety attached at the C-3 position of the triterpenoid core with a cyclohex-3-ene-1-carboxylic acid substituted with a CH2F moiety at the carbon atom α- to the pharmacophoric carboxylic acid. This structural element provided a new vector with which to explore structure-activity relationships (SARs) and led to compounds with improved polymorphic coverage while preserving pharmacokinetic (PK) properties. The approach to the design of GSK3640254, the development of a synthetic route and its preclinical profile are discussed. GSK3640254 is currently in phase IIb clinical trials after demonstrating a dose-related reduction in HIV-1 viral load over 7-10 days of dosing to HIV-1-infected subjects.

Adsorptive Structure and Mobility on Carbon Nanotube Exteriors Using Benzoic Acid as a Molecular Probe of Amphiphilic Water Contaminants.

Benzoic acid is the simplest aromatic carboxylic acid that is also a common water contaminant. Its structural and amphiphilic properties are shared by many other contaminants of concern. Based on a molecular dynamics study, this work reports the competitive adsorption of benzoic acid with water on the curved exteriors of carbon nanotubes of varying oxygen content. With the help of cylindrically approximated pair correlation functions, carboxyl-carboxyl associations were found to serve as an additional mechanism providing stability to the adsorbed benzoic acid on tube exteriors. These associations are secondary to the main aromatic-aromatic interactions during the adsorption process and therefore were not sufficient to establish the energy hierarchy at the adsorbed state with increase in surface oxygen content. The same mechanism was previously ascribed to the adsorption of the structurally similar but bulkier tannic acid. Both water and benzoic acid were organized into numerous mobility groups and a correspondence was established between species residence time and the average translation time taken to escape the tube vicinity. Vigorous exchange of water molecules among the first adsorption shell, the second adsorption shell, and the immediate vicinity radially outside was estimated to take place within a short time of about 10 ps.

Synthesis, characterization and biocompatibility of guar gum-benzoic acid.

A novel chemical functionalization of guar gum (GG) by benzoic acid (BA) via nucleophilic substitution reaction in aqueous solution has been reported. BA moieties are chosen due to coordination chemistry of carboxylic acid moieties, hydrophobicity and intermolecular interaction of aromatic rings. The presence of conjugated BA on guar gum-benzoic acid (GG-BA) with grafting density of 5.5% is confirmed by 1H NMR. Amorphous GG-BA with irregular morphology has been studied by UV-Vis, FTIR, XRD, SEM, TEM, TGA, computational chemistry and contact angle measurement. GG-BA in a concentration range from 0 to 4000 µg mL-1 has good biocompatibility to mouse embryonic fibroblasts (MEF), human mammary epithelial cells (MCF-10A) after 48 and 72 h of treatment using WST-1 assay. GG-BA shows great potential for the development of biomaterials such as bioadhesives, hydrogels, and coacervates.

Novel diosgenin-amino acid-benzoic acid mustard trihybrids exert antitumor effects via cell cycle arrest and apoptosis.

In discovering new powerful antitumor agents, two series of novel diosgenin-amino acid-benzoic acid mustard trihybrids (7a-7 g and 12a-12 g) were designed and synthesized. The antiproliferative activities were tested against five human tumor cell lines and one normal cell line using CCK-8 assays. Among the trihybrids, 12e was the most promising compound, which inhibited T24 cells with IC50 value of 6.96 µM, and was stronger than its parent compound diosgenin (IC50 = 32.33 µM). In addition, 12e had weak cytotoxicity on the normal GES-1 cell line (IC50 = 213.74 µM). Moreover, 12e could cause G2/M cell cycle arrest, increase the percentage of apoptosis, induce mitochondrial depolarization, and promote reactive oxygen species generation in T24 cells. Further studies on antitumor mechanism demonstrated that 12e triggered the intrinsic (mitochondrial) and extrinsic (death receptor) apoptotic pathways. More importantly, 12e could inhibit T24 cell proliferation in an in vivo zebrafish xenograft model. Therefore, 12e, as a novel trihybrid with potent cytotoxicity, might be applied as a promising skeleton for antitumor agents, which deserved further optimization.

Molecular Transformation Based on an Innovative Catalytic System.

Novel innovative catalytic systems such as hydrogen-bond donors and thiourea hybrid catalysts have been developed for the asymmetric synthesis of biologically important pharmaceuticals and natural products. Benzothiadiazines possess a stronger hydrogen-bond donor ability compared to thioureas and exhibit remarkable catalytic performance for the activation of α,ß-unsaturated amides. Hybrid thioureas (bearing an arylboronic acid and an ammonium salt) efficiently promote the hetero-Michael addition to α,ß-unsaturated carboxylic acids and the O-alkylation of keto enols with 5-chlorofuran-2(5H)-one. These hybrid catalysts enable the first total synthesis of non-racemic avenaol, a noncanonical strigolactone, as well as the asymmetric synthesis of several pharmaceuticals. In addition, this study discovers unique chemical phenomena (i.e., the dual role of benzoic acid as a boron ligand and a proton shuttle, the chirality switch of products by solvent used, and the dynamic kinetic resolution of a racemic electrophile in an SN2-type reaction).

4-Pyridone-3-carboxylic acid as a benzoic acid bioisostere: Design, synthesis, and evaluation of EP300/CBP histone acetyltransferase inhibitors.

Histone acetyltransferases (HATs) play a crucial role in post-translational modification. Among them, overexpression, mutation, or hyperfunction of EP300/CBP has been associated with various cancers. In this study, we identified the novel compound 2-chloro-5-[5-[(E)-[1-(3-chlorophenyl)-3-methyl-5-oxo-pyrazol-4-ylidene]methyl]-2-furyl]benzoic acid (1) as an EP300 HAT inhibitor via virtual screening. Further research has been focused on the design, synthesis, and in vitro biological evaluation of virtual hit derivatives. The studies revealed that 4-pyridone-3-carboxylic acid derivatives exhibited bioisosterism of benzoic acid. Replacement proved effective, providing compounds with similar EP300 HAT-inhibitory activity and improved cell growth-inhibitory activity compared to the benzoic acid analogs. Through these studies, we identified a potent and selective EP300/CBP HAT inhibitor.

Theoretically derived thermodynamic properties can be improved by the refinement of low-frequency modes against X-ray diffraction data.

Herein, a framework for the estimation of the thermodynamic properties of molecular crystals via the refinement of frequencies from density functional theory calculations against X-ray diffraction data is presented. The framework provides an efficient approach to including the contribution of acoustic modes in the thermodynamic properties. The obtained heat capacities for urea, the α- and ß-glycine polymorphs, benzoic acid, and 4'-hydroxyacetophenone are in good agreement with those from adiabatic calorimetry.

Synthesis, In Silico and In Vitro Evaluation of Antimicrobial and Toxicity Features of New 4-[(4-Chlorophenyl)sulfonyl]benzoic Acid Derivatives.

The multi-step synthesis, physico-chemical characterization, and biological activity of novel valine-derived compounds, i.e., N-acyl-α-amino acids, 1,3-oxazol-5(4H)-ones, N-acyl-α-amino ketones, and 1,3-oxazoles derivatives, bearing a 4-[(4-chlorophenyl)sulfonyl]phenyl moiety are reported here. The structures of the newly synthesized compounds were confirmed by spectral (UV-Vis, FT-IR, MS, 1H- and 13C-NMR) data and elemental analysis results, and their purity was determined by RP-HPLC. The new compounds were assessed for their antimicrobial activity and toxicity to aquatic crustacean Daphnia magna. Also, in silico studies regarding their potential mechanism of action and toxicity were performed. The antimicrobial evaluation revealed that the 2-{4-[(4-chlorophenyl)sulfonyl]benzamido}-3-methylbutanoic acid and the corresponding 1,3-oxazol-5(4H)-one exhibited antimicrobial activity against Gram-positive bacterial strains and the new 1,3-oxazole containing a phenyl group at 5-position against the C. albicans strain.

Nonpeptidic, Polo-Box Domain-Targeted Inhibitors of PLK1 Block Kinase Activity, Induce Its Degradation and Target-Resistant Cells.

PLK1, polo-like kinase 1, is a central player regulating mitosis. Inhibition of the subcellular localization and kinase activity of PLK1 through the PBD, polo-box domain, is a viable alternative to ATP-competitive inhibitors, for which the development of resistance and inhibition of related PLK family members are concerns. We describe novel nonpeptidic PBD-binding inhibitors, termed abbapolins, identified through successful application of the REPLACE strategy and demonstrate their potent antiproliferative activity in prostate tumors and other cell lines. Furthermore, abbapolins show PLK1-specific binding and inhibitory activity, as measured by a cellular thermal shift assay and an ability to block phosphorylation of TCTP, a validated target of PLK1-mediated kinase activity. Additional evidence for engagement of PLK1 was obtained through the unique observation that abbapolins induce PLK1 degradation in a manner that closely matches antiproliferative activity. Moreover, abbapolins demonstrate antiproliferative activity in cells that are dramatically resistant to ATP-competitive PLK1 inhibitors.

Antifungal Activity of Chemical Constituents from Piper pesaresanum C. DC. and Derivatives against Phytopathogen Fungi of Cocoa.

In this study, the antifungal potential of chemical constituents from Piper pesaresanum and some synthesized derivatives was determined against three phytopathogenic fungi associated with the cocoa crop. The methodology included the phytochemical study on the aerial part of P. pesaresanum, the synthesis of some derivatives and the evaluation of the antifungal activity against the fungi Moniliophthora roreri, Fusarium solani and Phytophthora sp. The chemical study allowed the isolation of three benzoic acid derivatives (1-3), one dihydrochalcone (4) and a mixture of sterols (5-7). Seven derivatives (8-14) were synthesized from the main constituents, of which compounds 9, 10, 12 and 14 are reported for the first time. Benzoic acid derivatives showed strong antifungal activity against M. roreri, of which 11 (3.0 ± 0.8 µM) was the most active compound with an IC50 lower compared with positive control Mancozeb® (4.9 ± 0.4 µM). Dihydrochalcones and acid derivatives were active against F. solani and Phytophthora sp., of which 3 (32.5 ± 3.3 µM) and 4 (26.7 ± 5.3 µM) were the most active compounds, respectively. The preliminary structure-activity relationship allowed us to establish that prenylated chains and the carboxyl group are important in the antifungal activity of benzoic acid derivatives. Likewise, a positive influence of the carbonyl group on the antifungal activity for dihydrochalcones was deduced.

Inhibition of neuroinflammation by MIF inhibitor 3-({[4-(4-methoxyphenyl)-6-methyl-2-pyrimidinyl]thio}1methyl)benzoic acid (Z-312).

Microglial overactivation-mediated neuroinflammation contributes greatly to the pathogenesis of neurodegenerative diseases, such as Parkinson's disease. Macrophage migration inhibitory factor (MIF) is a pleiotropic proinflammatory cytokine that is involved in the pathophysiology of various inflammatory diseases by inducing various proinflammatory cytokines. Compound 3-({[4-(4-methoxyphenyl)-6-methyl-2-pyrimidinyl]thio}methyl)benzoic acid (Z-312) is a novel small -molecule inhibitor of MIF tautomeric activity. In this study, we investigated the anti-inflammatory effects of Z-312 on liposaccharide (LPS)-induced neuroinflammation in vitro and in vivo. The results showed that Z-312 significantly decreased the production of nitric oxide (NO), interleukin (IL)-1ß, tumor necrosis factor (TNF)-α and IL-6 in LPS-stimulated microglial cells. Mechanistically, nuclear translocation of the p65 subunit of nuclear factor (NF)-κB, degradation and phosphorylation of IκBα, NF-κB transcriptional activity and phosphorylation of p38 mitogen-activated protein kinase (MAPK) and JNK were markedly attenuated by pretreatment with Z-312 in BV-2 microglial cells. In addition, Z-312 suppressed the neurotoxic effects of cell culture medium of LPS-activated BV-2 microglia on cocultured mouse HT22 neuroblastoma cells. An in vivo study demonstrated that Z-312 markedly ameliorated microglial activation and subsequent DA neuron loss in an LPS-induced Parkinson's disease (PD) mouse model. These results suggest that MIF inhibitor Z-312 may be a promising neuroprotective agent for the treatment of neuroinflammation-mediated neurological diseases.

Comprehensive Two-Dimensional Gas Chromatography-Mass Spectrometry Analysis of Exhaled Breath Compounds after Whole Grain Diets.

Exhaled breath is a potential noninvasive matrix to give new information about metabolic effects of diets. In this pilot study, non-targeted analysis of exhaled breath volatile organic compounds (VOCs) was made by comprehensive two-dimensional gas chromatography-mass spectrometry (GCxGC-MS) to explore compounds relating to whole grain (WG) diets. Nine healthy subjects participated in the dietary intervention with parallel crossover design, consisting of two high-fiber diets containing whole grain rye bread (WGR) or whole grain wheat bread (WGW) and 1-week control diets with refined wheat bread (WW) before both diet periods. Large interindividual differences were detected in the VOC composition. About 260 VOCs were detected from exhaled breath samples, in which 40 of the compounds were present in more than half of the samples. Various derivatives of benzoic acid and phenolic compounds, as well as some furanones existed in exhaled breath samples only after the WG diets, making them interesting compounds to study further.