Identifying Putative Biomarkers of Foodborne Pathogens Using a Metabolomic Approach.

Metabolomics is the study of low molecular weight biochemical molecules (typically <1500 Da) in a defined biological organism or system. In case of food systems, the term "food metabolomics" is often used. Food metabolomics has been widely explored and applied in various fields including food analysis, food intake, food traceability, and food safety. Food safety applications focusing on the identification of pathogen-specific biomarkers have been promising. This chapter describes a nontargeted metabolite profiling workflow using gas chromatography coupled with mass spectrometry (GC-MS) for characterizing three globally important foodborne pathogens, Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella enterica, from selective enrichment liquid culture media. The workflow involves a detailed description of food spiking experiments followed by procedures for the extraction of polar metabolites from media, the analysis of the extracts using GC-MS, and finally chemometric data analysis using univariate and multivariate statistical tools to identify potential pathogen-specific biomarkers.

[Determination of 8 N-nitrosamines in the workplace air by GC-MS/MS method].

Objective: To establish a method for the determination of eight N-nitrosamines (N-nitrosodimethylamine, N-nitrosodimethylamine, N-nitrosomethylmethylamine, N-nitrosodibutylamine, N-nitrosopropylamine, N-nitrosomorpholine, N-nitrosodianiline and N-nitrosopiperidine) in the air of workplace by gas chromatography-tandem mass spectrometry (GC-MS/MS) . Methods: From January to August 2023, eight N-nitrosamines in the air of workplace were collected by ThermoSorb/N column, eluted with 4 ml methanol-dichloromethane (1∶1 volume ratio), separated by VF-624 ms capillary column, detected by multiple reaction monitoring mode and quantified by external standard method. The detection limit and precision of the method were also analyzed. Results: The linear range of the method for the determination of eight N-nitrosamines was 1.0-20.0 µg/L, the correlation coefficient was 0.9993-0.9999, the detection limit was 0.051-0.132 µg/L, and the minimum quantitative concentration was 0.030-0.078 µg/m(3) (calculated by collecting 22.5 L of air sample and eluting with 4.0 ml stripping liquid). The within-run precisions were 2.05%-6.89% and the between-run precisions were 2.41%-8.26%. The desorption rates were 67.20%-102.60%. The sample can be kept at least 7 days at 4 ℃. Conclusion: GC-MS/MS method for the determination of eight N-nitrosamines in workplace air has high sensitivity and good precision, and can accurately determine the content of eight N-nitrosamines in workplace air.

Ethion food poisoning outbreak in Pereira, Colombia, 2022.

INTRODUCTION: Ethion is an organophosphate used as an acaricide and insecticide, that is restricted worldwide. In Colombia, pesticide poisoning is the third most common cause of chemical intoxication. On 9 October 2022, an outbreak of ethion poisoning occurred in Pereira. The aim of this study was to describe the clinical and epidemiological characteristics of the outbreak. METHODS: This is a descriptive study of an outbreak of organophosphate poisoning. The onset of symptoms occurred on 9 October 2022, following the consumption of empanadas. Information was collected on sociodemographic characteristics and clinical manifestations, as well as from paraclinical examinations. Data were obtained from clinical histories, field epidemiological investigations, and inspection visits. Food samples were collected for analysis by gas chromatography-mass spectrometry. Attack rates, proportions, and measures of central tendency, dispersion, and position were calculated. RESULTS: The case definition was met by 37 individuals with a median age of 30 years; all presented with muscarinic symptoms, 29 patients presented with nicotinic symptoms, and 20 patients presented with neurological symptoms. Males were the most affected (57%), and the most common time of symptom onset was 10:00 am. Twenty-three patients (62%) required intensive care unit admission, of whom 14 (38%) required mechanical ventilation. No deaths were reported. Erythrocyte acetylcholinesterase activity was reduced in all patients. Ethion was detected in mass-prepared maize and empanadas at concentrations greater than 0.1 mg/kg. The consumption of empanadas was identified as the common source. DISCUSSION: In Colombia, pesticide poisonings are the third most common type of poisoning caused by chemical substances reported to the National Health Institute through the National Public Health Surveillance System. In the present outbreak, ethion was in empanadas, likely due to contamination of cooking oil. CONCLUSIONS: We describe a large ethion-contaminated food poisoning outbreak reported in Colombia. The main symptoms were muscarinic, and the main treatment measures employed were atropine and respiratory support. Increased awareness of pesticide poisoning and training for food handlers are needed.

Novel sampling and gas-phase derivatization strategy: Proof-of-concept by profiling ionic polar metabolites using gas chromatography-mass spectrometry.

Metabolomic research involves the comprehensive analysis of metabolites in biological samples and has many applications. Gas chromatography-mass spectrometry (GC-MS) is an established and widely used approach for metabolic profiling. However, sample preparation and metabolite derivatization are time-consuming, and derivatization options are limited. We propose gas-solid phase derivatization (GSPD) as a novel sampling and derivatization method that uses a silica monolith substrate and gaseous derivatization reagents for metabolomics using GC-MS. We developed a method to measure the organic acids and sugar phosphates responsible for glycolysis and the tricarboxylic acid (TCA) cycle. GSPD simplifies the sample preparation and can be applied to derivatization reactions that are difficult to perform in solution owing to solvent limitations. The developed method was applied to human plasma and tomato pulp and was shown to have a higher detection performance than the conventional method. This study provides a strategy to simplify sample preparation and expand derivatization options for GC-MS-based metabolomics.

Methyltrimethoxysilane modified tin dioxide microspheres with hydrophobic networks and abundant adsorbed oxygen for efficient solid-phase microextraction of polychlorinated biphenyls.

Methyltrimethoxysilane (MTMS) modified tin dioxide microspheres (MTMS/SnO2) were prepared by a facile hydrothermal method and heated reflux reaction strategy. The characterization results indicate that the modification of MTMS induced the formation of a hydrophobic network within the composites, while maintaining abundant adsorbed oxygen species. Subsequently, the MTMS/SnO2 microspheres were used as a solid-phase microextraction (SPME) coating for the efficient extraction and sensitive determination of trace polychlorinated biphenyls (PCBs) in aqueous solutions coupled to gas chromatography-mass spectrometry. MTMS/SnO2 coating exhibited superior extraction performances for PCBs compared with commercial SPME and pure SnO2 microspheres coatings, owing to the hydrophobic crosslinking and adsorbed oxygen-enhanced hydrogen bonding. The proposed analytical method presented respectable linearity in the concentration range 0.25-1000 ng L-1, with low limits of detection varying from 0.036 to 0.14 ng L-1 for seven PCBs and excellent precision, with relative standard deviations of 5.7-9.8% for a single fiber and 8.2-13.1% for five fibers. Finally, the proposed method was successfully used for determination of PCBs in real water with recoveries ranging from 75.8 to 115.6%. This study proposed a new type SPME coating of MTMS/SnO2 microspheres, which extended the potential of SnO2 in capturing and determining organic pollutants.

[Rapid determination of polycyclic aromatic hydrocarbons and phthalates in tap water by SBSE combined with GC-MS].

OBJECTIVE: To develop a method which is used for rapid determination of 16 kinds of polycyclic aromatic hydrocarbons(PAHs) and 16 kinds of phthalates(PAEs) in tap water by stirring rod adsorption extraction(SBSE) combined with gas chromatography-mass spectrometry(GC-MS). METHODS: The twister mixing rod coated with polydimethylsiloxane(PDMS) and ethylene glycol-polydimethylsiloxane(EG-silicone) was used to enrich analyte from 50 mL tap water. The twister mixing rod coated with EG-silicone was directly placed into the sample bottle containing 50 mL of tap water, while fixing the PDMS stir bar on the inner wall of the sample bottle and immersing it in the liquid. Add 5%(W/V) sodium chloride to the sample bottle, followed by adding 5% methanol. Stir at room temperature for 2 hours for extraction. Next, remove the mixing stick and dry its surface. The pre-prepared SBSE was analyzed by TD-GC/MS, with the optimized thermal desorption conditions: desorption temperature 275 ℃, desorption time 15 min, cryofocusing temperature-40 ℃. RESULTS: Regression equations revealed acceptable linearity(correlation coefficients >0.986) across the working-standard range from 200-2000 ng/L for the 32 analytes. The limits of detection(LODs)were further evaluated were from 1.13-121 ng/L. With the optimized pretreatment method, the spiked recoveries of tap samples(200 and 2000 ng/L)were in the range of 62.5%-98.4% with the relative standard deviations(RSDs) of 3.5%-25.3%. CONCLUSION: The established method can realize the rapid detection of high throughput in the laboratory, it is simple, convenient to operate, and the extraction and analysis time is short.

Fish Fillet Analogue Using Formulation Based on Mushroom (Pleurotus ostreatus) and Enzymatic Treatment: Texture, Sensory, Aromatic Profile and Physicochemical Characterization.

The growing demand for alternative sources of non-animal proteins has stimulated research in this area. Mushrooms show potential in the innovation of plant-based food products. In this study, the aim was to develop prototype fish fillets analogues from Pleurotus ostreatus mushrooms applying enzymatic treatment (ß-glucanase and transglutaminase-TG). A Plackett-Burman 20 experimental design was used to optimize forty variables. Oat flour (OF) exerted a positive effect on the hardness and gumminess texture parameters but a negative effect on cohesiveness and resilience. Soy protein isolate (SPI) exhibited a positive effect on elasticity, gumminess and chewiness, while acacia gum had a negative effect on elasticity, cohesiveness and resilience. After sensory analysis the assay with 1% cassava starch, 5% OF, 5% SPI, 0.1% transglutaminase (240 min/5 °C), 1% coconut oil, 1% soybean oil, 0.2% sodium tripolyphosphate, 0.6% ß-glucanase (80 °C/10 min) and without ß-glucanase inactivation was found to exhibit greater similarity to fish fillet. The classes hydrocarbons, alcohols and aldehydes are the predominant ones in aromatic profile analysis by chromatography and electronic nose. It is concluded that a mushroom-based analogue of fish fillet can be prepared using enzymatic treatment with TG.

The Influence of Planting Sites On the Chemical Compositions of Chrysanthemum morifolium Flowers (Chuju) as Revealed by Py-GC/MS Combined with Multivariate Statistical Analysis.

Chuju, a cultivar of Chrysanthemum morifolium, has been traditionally cultivated for over 2000 years in China for both ornamental and medicinal purposes. To date, investigations into the chemical composition of this plant have indicated that it contains compounds with extensive biological activities, although detailed information on the chemical composition of Chuju remains scarce. In the present study, the chemical compositions of Chuju flowers were investigated across five sites in the core Chuju planting area in Anhui province, China. Analytical pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) was used to explore variations in flower chemical fingerprints from different Chuju planting sites. The study identified approximately 200 components in Chuju flowers and stems, including high levels of fatty acids, lipids, polysaccharides and terpenoids. Multivariate statistical analysis indicated that 16 chemical compounds were influential determinants of the chemical fingerprint and could be used to distinguish two clusters in the five core planting areas. The established Py-GC/MS analytical workflow could provide a basis for determining the chemical fingerprints of Chuju and help elucidate that products contain a reproducible content of bioactive compounds and overall quality for potential development of health and medicinal purposes.

Characterization of the flavor profile and dynamic changes in Chinese traditional fish sauce (Yu-lu) based on electronic nose, SPME-GC-MS and HS-GC-IMS.

In this study, flavor characteristics and dynamic change of Chinese traditional fermented fish sauce (Yu-lu) with different fermentation time (2, 4, 6, 8, and 12 months) were analyzed. The electronic nose analyses confirmed a notable flavor change in fish sauce samples from different stages. During the 12-months fermentation, the total volatile compounds in fish sauce increased from 3.9 mg/L to 13.53 mg/L. Acids, aldehydes, esters and phenols were the main aroma substances and their contents gradually increased during the fermentation process. The PCA of GC-MS and GC-IMS showed that fish sauce samples from different fermentation periods can be well distinguished. A total of 110 volatile compounds identified by GC-MS, and 102 volatile compounds were detected by GC-IMS. Among them, 13 compounds were identified by both GC-MS and GC-IMS. The most varieties (49) of volatiles appeared after 8 months of fermentation. The odor activity value (OAV) analysis showed that 10 volatile compounds were considered as characteristic flavor in traditional fish sauce. The variable influence on projections (VIPs) in PLS-DA models constructed by GC-MS and GC-IMS identified 5 and 10 volatile compounds as biomarkers, respectively. Our results revealed the dynamic changes of characteristic flavor in fish sauce in combination of GC-MS and GC-IMS, which provides theoretical basis for the production and flavor regulation of fish sauce.

Identification of odor-active compounds in Nile tilapia (Oreochromis niloticus) from recirculated aquaculture systems: A case study with different depuration procedures.

Off-flavors are a major challenge for companies using recirculated aquaculture systems (RAS). In the presented work, we comprehensively characterize the odorant composition of Nile tilapia (Oreochromis niloticus) raised in RAS and compare the impact of two depuration processes on the odorant composition and aroma profile of the fish. Fish collected from the production tank and after two different tank pre-disinfection approaches in the depuration process (high pH versus H2O2) were investigated. A combined sensory-instrumental investigation revealed the presence of 115 odorants, of which 83 were successfully identified. The compounds decanal, tridecanal, (Z)-1,5-octadien-3-one, octane-2,3-dione, benzophenone, non-3-yn-1-ol, γ-dodecalactone, (Z)-geranylacetone, 2,3-diethyl-5-methylpyrazine, 1-methylpyrrolidin-2-one, 2-acetyl-2-thiazoline, benzothiazole, skatole, and 5α-androst-16-en-3-one were detected with the highest flavor dilution factors and are described for the first time as odor-active compounds in fish from RAS. The results indicate that depuration decreased the levels of 78 different odorants from the fish, including the potent earthy smelling odorants geosmin, isoborneol and 2,3-diethyl-5-methylpyrazine.

Innovative insights into the roasting-driven transformation of volatile compounds and quality markers in flaxseed (Linum usitatissimum L.) oil.

Roasting is essential for developing the characteristic aroma of flaxseed oil (FSO), yet its impact on oil quality remains underexplored. This study employed headspace-gas chromatography-mass spectrometry coupled with multivariate analysis to elucidate the dynamic changes in volatile compounds and quality characteristics of FSO subjected to varying roasting temperatures. Our findings revealed that seven key aroma compounds, identified through the variable importance in the projection scores of partial least square-discrimination analysis models and relative aroma activity value, served as molecular markers indicative of distinct roasting temperatures. These compounds included 2,5-dimethylpyrazine, 2-pentylfuran, (E)-2-pentenal, 2-ethyl-3,6-dimethylpyrazine, heptanal, octanal, and 2-hexenal. Notably, roasting at 200°C was found to enhance oil stability and antioxidant capacity, with phenolic compounds and Maillard reaction products playing synergistic roles in bolstering these qualities. Network analysis further uncovered significant correlations between these key aroma compounds and quality characteristics, offering novel perspectives for assessing FSO quality under diverse roasting conditions. This research not only enriched our understanding of the roasting process's impact on FSO but also provided valuable guidance for the optimization of industrial roasting practices. This study would provide important practical applications in aroma regulation and process optimization of flaxseed oil. .

The morphology of the pygidial glands and the chemical composition of their secretions of four sphodrine ground beetle species (Carabidae: Platyninae).

Ground beetles possess a pair of pygidial glands that produce and release secretions that play an important role in defense against predators. The morphology of these glands and the chemical composition of their products were studied in four species of the tribe Sphodrini: Calathus (Calathus) fuscipes (Goeze, 1777), C. (Neocalathus) cinctus Motschulsky, 1850, C. (N.) melanocephalus (Linnaeus, 1758) and Laemostenus (Antisphodrus) elongatus (Dejean, 1828). The morphological analyzes of the glands of the four taxa mentioned were carried out for the first time using bright-field and nonlinear microscopy. All morphological structures were precisely measured and photographed. The pygidial gland secretions of C. (C.) fuscipes and L. (A.) elongatus were analyzed for the first time using gas chromatography-mass spectrometry. A total of 30 compounds were detected from the extracts of pygidial gland secretions of the four Sphodrini species studied. The simplest chemical mixture was found in L. (A.) elongatus, while the most complex secretion was that of C. (C.) fuscipes. 1-Undecanol, which we were able to detect in all taxa examined here, and dodecyl butyrate, which was detected in the three Calathus species, have never before been detected in the secretions of ground beetles.

Passive sampling of high production volume chemicals and polycyclic aromatic hydrocarbons in urban atmospheres near petrochemical sites: Uptake rate determination and application.

This study describes the use of passive sampling followed by pressurised liquid extraction and gas chromatography-mass spectrometry for monitoring high production volume chemicals (HPVCs), such as benzothiazoles, benzesulfonamides, phthalate esters (PAEs), organophosphate esters, ultraviolet stabilizers, and phenolic antioxidants and polycyclic aromatic hydrocarbons (PAHs) in urban atmospheres close to a petrochemical area. To obtain accurate results when applying passive sampling, the uptake rates of each target compound for the sampling time applied must be known. Firstly, passive sampling was calibrated for two months and uptake rates of HPVCs and PAHs in an urban atmosphere determined using active sampling as the reference method. The obtained results showed experimental diffusive uptake rates between 1.6 m3 day-1 and 27 m3 day-1 for 32 of the target compounds that will allow enable cost-effective long-term monitoring campaigns of HPVCs to be performed. Secondly, the experimentally obtained uptake rates were used to monitor the concentrations of HPVCs and PAHs at six urban sampling sites close to the two petrochemicals parks in Tarragona (Spain) during a period the two months. Regardless of the sampling campaign, PAEs and PAHs were the families of compounds found at the highest concentration levels, with a sum of their mean values of 23 ng m-3 and 20 ng m-3, respectively.

Presence, behaviour, and risk assessment of volatile methylsiloxanes in wastewater: A year-long comprehensive study within a wastewater treatment plant.

The awareness of possible environmental hazards caused by the widespread global use of volatile methylsiloxanes (VMSs) in personal care products (PCPs) and industrial processes has been increasing. Sewage containing these compounds may reach wastewater treatment plants (WWTPs), which are hotspots of their release into the environment. The levels, distribution, and potential risks of VMSs were studied in an unprecedently comprehensive sampling strategy (four seasonal campaigns) along the water line of a WWTP: the main influent entrance (SA1), after the preliminary treatment (SA2), after the primary treatment (SA3) and after the secondary treatment (the treated effluent; SA4). This WWTP was selected as a representative of the conventional set up based on a secondary treatment, allowing a similar approach in numerous facilities worldwide. Seven VMSs (L3, L4, L5, D3, D4, D5, D6) were analysed in wastewater samples by a small-scale liquid-liquid extraction (LLE) protocol, followed by gas chromatography-mass spectrometry (GC-MS), and the cyclic VMSs were dominant at all sampling sites and in all seasons. Considering the whole year, the total VMSs ranged from 0.4 to 22.5 µg L-1 for SA1, 0.03 to 33.7 µg L-1 for SA2, below method detection limit (MDL) to 13.2 µg L-1 for SA3 and 98 %). According to the risk quotients (RQ), only 18 SA4 samples (32 %) presented a minimal risk to the receiving media (0.01 ≤ RQ < 0.1). However, considering the absence of a secondary treatment or a direct discharge without treatment, there may be a risk to the environment.

Determination of amphetamines in hair samples using microextraction by packed sorbent and gas chromatography-mass spectrometry.

Several protocols for the analysis of amphetamine-type stimulants (ATS) in hair have been developed over the years, with microextraction by packed sorbent (MEPS) being used for drugs like opiates, cocaine and ketamine. However, concerning ATS determination in hair samples, this approach has only been applied so far to amphetamine (AMP) and methamphetamine (MAMP). This study aimed at developing and validating a MEPS-based procedure for the determination in hair of not only AMP and MAMP but also of 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), 1-(1,3-benzodioxol-5-yl)propan-2-yl (ethyl)amine (MDE) and N-methyl-1-(1,3-benzodioxol-5-yl)-2-aminobutane (MBDB) as well. Hair, 50 mg, was incubated with 1 M sodium hydroxide (NaOH) at 45°C overnight, neutralization with 10 M hydrochloric acid (HCl) and centrifugation followed. The design of experiments approach was used for MEPS optimization, with the final optimized conditions including conditioning (250 µL methanol and deionized water), loading (18 × 100 µL) and elution (7 × 100 µL 2% NH4OH in acetonitrile). The eluted extract was evaporated to dryness and underwent microwave-assisted derivatization with N-methyl-bis(trifluoroacetamide) (MBTFA), and it was afterwards injected onto the gas chromatography-mass spectrometer (GC-MS). The obtained recoveries ranged between 8% and 14% for AMP, 14% and 20% for MAMP, 10% and 15% for MDA, 18% and 28% for MDMA, 25% and 43% for MDE and 34% and 52% for MBDB, and the method was linear from 0.2 to 5.0 ng/mg. Precision and accuracy were in accordance with international method validation guidelines. This novel method involving MEPS coupled to GC-MS offers a swift, eco-friendly and cost-effective alternative to traditional procedures for detecting these AMPs in hair samples.

Determination of Anthropogenic Pollutants in Adipose Tissue of the Caspian Seal Pusa caspica Gmelin, 1788 by High-Resolution Accurate Mass Spectrometry.

Tissue contamination with persistent organic pollutants (POPs) in organisms proved possible to comprehensively characterize in a single test by combining gas chromatography and high-resolution accurate mass spectrometry. Adipose tissue samples were collected from two Caspian seals (Pusa caspica Gmelin, 1788) found dead on the Caspian Sea shore in 2020. Organochlorine pesticides, primarily DDT and HCH, and polychlorinated biphenyls (PCBs) were major pollutants found in the Caspian seals. The distribution of metabolites indicated the absence of recent pesticide use. The PCB content was relatively high, but still at the lower limit of the range of values determined previously, as was also the case with pesticides. Chlordanes, polychlorinated naphthalenes, and polybrominated diphenyl ethers were detected in minor quantities and were therefore not considered to be major pollutants of the Caspian seal. The pollutant levels were below a threshold at which a distinct effect on seal health can be expected. High-resolution accurate mass (HRAM) spectrometry was found to provide a convenient tool for both targeted and nontargeted analyses of a wide range of organic pollutants in a single experiment.

Evaluation of polycyclic aromatic hydrocarbon contents in marine products in South Korea and risk assessment using the total diet study.

This study investigated levels of eight polycyclic aromatic hydrocarbons (PAH8) compounds in both raw and processed marine products in South Korea. Katsuobushi exhibited the highest concentration of benzo[a]pyrene, at 14.22 µg/kg, exceeding the European Commission's regulation level of 5.0 µg/kg. The total PAH8 concentration in katsuobushi was 220.5 µg/kg. Among the product categories, shellfish had the highest detection rate (70%), followed by fish (19%) and crustacea (8%), with chrysene being the most prominent PAH8 congener in all marine products. Grilled fish predominantly contained pyrogenic PAHs from combustion byproducts, while shellfish primarily contained petrogenic ones from the aquatic environment. Grilling, smoking, and drying processes significantly contributed to the formation of PAH8 in these food products. Based on the results of a risk assessment using a margin of exposure approach through a total diet study, exposure to PAH8 from marine products is considered to pose low concern to the South Korean population. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01491-y.

Microplastics are associated with elevated atherosclerotic risk and increased vascular complexity in acute coronary syndrome patients.

BACKGROUND: Microplastics, widely present in the environment, are implicated in disease pathogenesis through oxidative stress and immune modulation. Prevailing research, primarily based on animal and cell studies, falls short in elucidating microplastics' impact on human cardiovascular health. This cross-sectional study detected blood microplastic concentrations in patients presenting with chest pain using pyrolysis-gas chromatography/mass spectrometry and evaluating inflammatory and immune markers through flow cytometry, to explore the potential effects of microplastic on acute coronary syndrome. RESULTS: The study included 101 participants, comprising 19 controls and 82 acute coronary syndrome cases. Notably, acute coronary syndrome patients exhibited elevated microplastic concentrations, with those suffering from acute myocardial infarction presenting higher loads compared to those with unstable angina. Furthermore, patients at intermediate to high risk of coronary artery disease displayed significantly higher microplastic accumulations than their low-risk counterparts. A significant relationship was observed between increased microplastic levels and enhanced IL-6 and IL-12p70 contents, alongside elevated B lymphocyte and natural killer cell counts. CONCLUSION: These results suggest an association between microplastics and both vascular pathology complexity and immunoinflammatory response in acute coronary syndrome, underscoring the critical need for targeted research to delineate the mechanisms of this association. HIGHLIGHTS: 1 Blood microplastic levels escalate from angiographic patency, to angina patients, peaking in myocardial infarction patients. 2 Microplastics in acute coronary syndrome patients are predominantly PE, followed by PVC, PS, and PP. 3 Microplastics may induce immune cell-associated inflammatory responses in acute coronary syndrome patients.

Kairomonal Effect of Hexane Extracts of Corcyra cephalonica and Spodoptera frugiperda on the Parasitizing Activity of Trichogramma pretiosum.

Egg parasitoids, particularly Trichogrammatidae, play a crucial role in global biocontrol efforts. Their behavior is influenced by chemicals emitted by their hosts, such as kairomones. Among them, Trichogramma pretiosum (Riley) (Hym.; Trichogrammatidae) shows promise as a biocontrol agent on destructive Fall Armyworm (FAW), Spodoptera frugiperda (J.E. Smith) (Lep.; Noctuidae). Given the invasiveness and widespread impact of FAW, early-stage prevention in the field is imperative. This study aimed to assess the potential of host insects viz.,Corcyra cephalonica (Stainton) (Lep.; Pyralidae) and S. frugiperda kairomones in optimizing the performance of T. pretiosum while parasitizing S. frugiperda. The top two hexane extracts from each host insect were also sent to JNU, AIRF in New Delhi for detailed GC-MS analysis. A four-armed olfactometer was developed to track the movements of T. pretiosum and validated with olfactory cues. Laboratory bioassays revealed that extracts from C. cephalonica and S. frugiperda eggs and moths effectively enhanced the performance of T. pretiosum. Optimal concentrations were determined through Petri dish bioassays, with C1 (10%) concentration of C. cephalonica eggs extract showing the highest Parasitoid Activity Index (PAI), percent parasitization, and adult emergence. Meanwhile, C2 (1%) concentration of S. frugiperda female extract exhibited the highest parasitization percentage and adult emergence. Further assessments in a polyhouse setting demonstrated that treated egg cards positioned 1 m from the release point achieved the highest mean percentage parasitization. Chemical composition analysis via GC-MS revealed that distinctive hydrocarbon and alcohol profiles in the extracts, suggesting their potential for manipulating parasitoid activity in biocontrol efforts. In the S. frugiperda female extract, 12 hydrocarbons and 3 alcohol groups were identified, with tetracontane as the predominant hydrocarbon compound followed by octane, heneicosane, and others. Meanwhile, the C. cephalonica egg extract displayed 9 hydrocarbons and 1 alcohol group, with dodecane leading in area percentage among the hydrocarbons followed by decane, nonane and others. The outputs of current study highlighted that T. pretiosum's utilization of kairomones from C. cephalonica and S. frugiperda, enhancing its search behavior for host eggs. The identification and synthesis of these kairomonal compounds have the potential to revolutionize pest management, emphasizing the role of kairomones in empowering natural predators and parasitoids for sustainable agriculture.

Tert-butylhydroquinone and tert-butylcatechol positivity as warning lights of skin sensitization to tert-butylphenol derivatives in adhesives and diabetes devices.

INTRODUCTION: Tert-butylphenol (TBP) derivatives, antioxidants in adhesives and diabetes devices, may provoke allergic contact dermatitis (ACD). OBJECTIVES: The objective of this study is to report sensitization to TBP derivatives in medical devices and to highlight that tert-butylhydroquinone (BHQ) and tert-butylcatechol (TBC) are potential screeners in this regard. METHODS: Fifteen patients with ACD from adhesives and diabetes devices were patch tested to different TBPs: BHQ 1% pet., TBC 0.25% pet., BHA 2% pet., BHT 2% pet., 4-tert-butylphenol (TBP) 1% pet. and 2,4-di-tert-butylphenol (di TBP) 1% pet. The culprit devices (medical adhesives, sanitary pads, diabetes devices) and TBP patch preparations were analysed using gas chromatography-mass spectrometry (GC-MS). RESULTS: BHQ (9/13), TBC (7/13), and to a lesser extent BHT (3/15), BHA (2/15) and TBP (2/13) gave positive reactions. Seven patients had developed ACD from adhesives and diabetes devices, respectively, and one patient from sanitary pads. GC-MS analyses of the medical devices and patch test materials confirmed the presence of the patch-test positive TBPs, or chemically related derivatives, or, interestingly, tert-butylbenzoquinones (BBQ) were found, that is, spontaneously formed, highly reactive TBP metabolites, likely (pseudo-) cross reacting with the patch tested TBPs. CONCLUSION: TBPs might be overlooked sensitizers in medical devices, and BHQ and TBC are potential screeners in this regard.