Chromatography-mass Spectrometry Research Articles

Non-Conventional Yeasts from Mozzarella Cheese Whey and Artisanal Sourdoughs: Leavening Capacity and Impact on Bread Sensory Profile

Non-conventional yeasts (NCYs) (i.e., non-Saccharomyces) are used as alternative starters to promote aroma complexity of fermented foods (e.g., bakery products). A total of 66 yeasts isolated from artisanal food matrices (bread and pizza sourdoughs and milk whey) from different geographical areas of the Campania region (Italy) were screened for physiological and technological characteristics such as leavening ability, resistance to NaCl and pH, exopolysaccharide and phytase activity production, and carbohydrate assimilation. Selected and isolated microorganisms were also used to study the leavening kinetics in experimental doughs as mixed inocula of two different strains. Volatile organic compounds (VOCs) of the inoculated doughs were analyzed with solid-phase microextraction/gas chromatography–mass spectrometry (SPME/GC-MS). Most of the strains belonged to non-Saccharomyces species (Pichia kudriavzevii, Kluyveromyces marxianus) and Saccharomyces (S. cerevisiae). Several strains produced exopolysaccharides (EPSs), that are important for dough rheological properties. Moreover, yeasts isolated from whey showed extracellular phytase activity. The mixed starter culture of the S. cerevisiae and NCY strains showed a synergic effect that enhanced the doughs’ aroma complexity. The use of non-conventional yeasts mixed with S. cerevisiae strains can be advantageous in the bakery industry because they improve the bread aroma profiles and nutritional properties by bioactive molecule production.

Efficient dissipation of acetamiprid, metalaxyl, S-metolachlor and terbuthylazine in a full-scale free water surface constructed wetland in Bologna province, Italy: A kinetic modeling study

The study investigated the dissipation ability of a vegetated free water surface (FWS) constructed wetland (CW) in treating pesticides-contaminated agricultural runoff/drainage water in a rural area belonging to Bologna province (Italy). The experiment simulated a 0.1% pesticide agricultural water runoff/drainage event from a 12.5-ha farm by dissolving acetamiprid, metalaxyl, S-metolachlor, and terbuthylazine in 1000 L of water and pumping it into the CW. Water and sediment samples from the CW were collected for 4 months at different time intervals to determine pesticide concentrations by multiresidue extraction and chromatography-mass spectrometry analyses. In parallel, no active compounds were detected in the CW sediments during the experimental period. Pesticides dissipation in the wetland water compartment was modeled according to best data practices by fitting the data to Single First Order (SFO), First Order Multi-Compartment (FOMC) and Double First Order in Parallel (DFOP) kinetic models. SFO (except for metalaxyl), FOMC and DFOP kinetic models adequately predicted the dissipation for the four investigated molecules, with the DFOP kinetic model that better fitted the observed data. The modeled distribution of each pesticide between biomass and water in the CW highly correlated with environmental indexes as Kow and bioconcentration factor. Computed DT50 by DFOP model were 2.169, 8.019, 1.551 and 2.047 days for acetamiprid, metalaxyl, S-metolachlor, and terbuthylazine, respectively. Although the exact degradation mechanisms of each pesticide require further study, the FWS CW was found to be effective in treating pesticides-contaminated agricultural runoff/drainage water within an acceptable time. Therefore, this technology proved to be a valuable tool for mitigating pesticides runoff occurring after intense rain events.

Impact of Argemone mexicana L. on tomato plants infected with Phytophthora infestans.

Fungal diseases can cause significant losses in the tomato crop. Phytophthora infestans causes the late blight disease, which considerably affects tomato production worldwide. Weed-based plant extracts are a promising ecological alternative for disease control. In this study, we analyzed the plant extract of Argemone mexicana L. using chromatography-mass spectrometry analysis (GC-MS). We evaluated its impact on the severity of P. infestans, as well as its effect on the components of the antioxidant defense system in tomato plants. The extract from A. mexicana contains twelve compounds most have antifungal and biostimulant properties. The findings of the study indicate that applying the A. mexicana extract can reduce the severity of P. infestans, increase tomato fruit yield, enhance the levels of photosynthetic pigments, ascorbic acid, phenols, and flavonoids, as well as decrease the biosynthesis of H2O2, malondialdehyde (MDA), and superoxide anion in the leaves of plants infected with this pathogen. These results suggest that using the extract from A. mexicana could be a viable solution to control the disease caused by P. infestans in tomato crop.

Insecticidal and antioxidant potential of volatile compounds and nanoparticles from Tulbaghia violacea Harv. inoculated with endophytic fungus Beauveria bassiana (Bals.-Criv.) Vuill

This study aimed to investigate the effect of the entomopathogenic fungus Beauveria bassiana on the growth and ability of Tulbaghia violacea to synthesise nanoparticles and volatile compounds. Tulbaghia violacea was inoculated by drenching with different concentrations of B. bassiana conidial concentrations (0 mL−1, 1 × 106 mL−1, 1 × 107, and 1 × 108 conidia mL−1) and the colonization of plant tissue in the different fungal treatments was evaluated. A UV–VIS spectrometer (SPECTROstar nano) was used to determine the presence of nanoparticles while volatile constituents in the plants were analysed with chromatography-mass spectrometry. Polyphenols, alkaloids, flavonoids and antioxidant contents were determined using referenced methods. At least 57 % of plants were successfully colonized at the highest concentration (1 × 108 conidia mL−1). The results showed that treating B. bassiana with T. violacea had no significant effect (P>0.05) on the growth parameters (height, number of leaves, aerial part fresh weight, aerial part dry weight, root fresh weight, and root dry weight) of T. violacea after four weeks post-treatment. The aqueous extracts of T. violacea from both control and B. bassiana-treated plants successfully synthesized gold nanoparticles. Furthermore, the aqueous extracts of plants and gold nanoparticles from both fungus and control treatments were equally toxic to mealybug and induced high mortality. The Gas chromatography–mass spectrometry (GC–MS) results revealed that the number of compounds detected in plants subjected to the different concentrations of fungal inoculum and control did not vary significantly (P>0.05) in leaves and roots. The polyphenol contents in the leaves were not significantly different (P>0.05) among treatments. Similarly, the antioxidant activities were not significantly influenced (P>0.05) by fungal treatment on both leaves and roots. However, T. violacea extracts reduced aqueous gold to gold nanoparticles in both control and fungus-treated plants.

Predictive value of bile acids as metabolite biomarkers for gallstone disease: A systematic review and meta-analysis.

The profiles of bile acids (BAs) in patients with gallstone disease (GSD) have been found to be altered markedly though in an inconsistent pattern. This study aims to characterize the variation of the BA profiles in GSD patients, thereby to discover the potential metabolite biomarkers for earlier detection of GSD. Literature search of eight electronic database in both English and Chinese was completed on May 11, 2023. The qualitative and quantitative reviews were performed to summarize the changes of BA profiles in GSD patients compared with healthy subjects. The concentrations of BAs were adopted as the primary outcomes and the weighted mean differences (WMDs) and 95% confidence interval (CI) were generated by random-effects meta-analysis models. A total of 30 studies were enrolled which included 2313 participants and reported the 39 BAs or their ratios. Qualitative review demonstrated serum Taurocholic Acid (TCA), Glycochenodeoxycholic acid (GCDCA), Glycocholic acid (GCA), Taurochenodeoxycholic acid (TCDCA), Glycodeoxycholic acid (GDCA) and Deoxycholic acid (DCA) were significantly increased in GSD patients compared with healthy subjects. Meta analysis was performed in 16 studies and showed that serum Total BAs (TBA) (WMD = 1.36μmol/L, 95%CI = 0.33; 2.4) was elevated however bile TBA (WMD = -36.96mmol/L, 95%CI = -52.32; -21.6) was declined in GSD patients. GCA (WMD = 0.83μmol/L, 95%CI = 0.06; 1.6) and TCA (WMD = 0.51μmol/L; 95%CI = 0.18; 0.85) were both increased in serum sample; TCDCA (WMD = 2.64mmol/L, 95%CI = 0.16; 5.12) was rising, however GCDCA (WMD = -13.82mmol/L, 95%CI = -21.86; -5.78) was falling in bile sample of GSD patients. The level of serum DCA in the GSD patients was found to be increased by using chromatography, yet decreased by chromatography mass spectrometry. The profiles of BAs demonstrated distinctive changes in GSD patients compared with healthy control subjects. Serum GCA, TCA and GCDCA, as the typically variant BAs, presented as a potential marker for earlier diagnosis of GSD, which could facilitate early prophylactic intervention. Yet, further validation of these biomarkers by longitudinal studies is still warranted in the future. PROSPERO registration number CRD42022339649.

Синтез новых S-производных 4-амино-1,3,5-триазин-2-тиона и их исследование методами ЯМР 1Н, 13С и хромато-масс-спектрометрии

4-Amino-1,3,5-triazine-2-thione 1 interacts with allyl bromide, 2-methyl-3-chloro-1-propene, 2,3-dibromopropene-1, prenyl bromide in DMFA/K2CO3 and with cinnamyl chloride, butenyl bromide in DMFA/NaOH to form 4-allylsulfanyl- 2, 4-(2-methylpropene-2-yl)sulfanyl- 3, 4-(2-bromopropene-2-yl)sulfanyl- 4, 4-(2-methylbutene-2-yl)sulfanyl- 5, 4-cinnamylsulfanyl- 6 and 4-(butene-1-yl)sulfanyl-1,3,5-triazine-2-amines 7, respectively. The structure of compounds 2–7 was studied by 1H NMR, as well as of compounds 5 and 7, in their case including 13C NMR; allyl sulfide 2, prenyl sulfide 5 and butenyl sulfide 7 were also studied using chromatography mass spectrometry. In the 1H NMR spectra of compounds 2–7, the weakest field signal in the range of 8.22–8.30 p.p.m. is the signal of the aromatic proton of the triazine cycle, manifested as a singlet. The signals of protons of the S-CH2 group are observed in a strong field – at 3.10–4.19 p.p.m. – depending on the presence of electron donor or electron acceptor groups in the alkenyl fragment. The protons of the =CH2 group are present only in the structure of sulfides 2–4 and 7; they form two signals in the 1H NMR spectra: one signal at 4.85–5.58 p.p.m., the second at 5.03–6.10 p.p.m. In the 13C NMR spectra of prenyl sulfide 5 and butenyl sulfide 7, the carbon atoms of the S-alkenyl groups resonate in the region of strong fields. In the region of weak fields, the signals of aromatic carbon atoms of the 1,3,5-triazine cycle are observed: 182.32–157.95 p.p.m. In the mass spectra of compounds 2, 5 and 7, the characteristic peaks are [M 15]+ and [M-33]+ peaks, the formation of which is associated with the fragmentation of molecular ions undergoing cleavage of the methyl radical and the •SH radical, respectively. The haloalkyl derivative of the heterocyclic series – 2-chloro-1-(2,2,4-trimethyl-4-phenyl-3,4-dihydroquinoline-1(2H)-yl) ethanoate – in reaction with compound 1 has led to the introduction of a new pharmacophore fragment into the simm-triazine molecule, which contributes to the expansion of the spectrum of potential biological activity of its derivatives.

Finding the best predictive model for hypertensive depression in older adults based on machine learning and metabolomics research.

Depression is a common comorbidity in hypertensive older adults, yet depression is more difficult to diagnose correctly. Our goal is to find predictive models of depression in hypertensive patients using a combination of various machine learning (ML) methods and metabolomics. Methods We recruited 379 elderly people aged ≥65 years from the Chinese community. Plasma samples were collected and assayed by gas chromatography/liquid chromatography-mass spectrometry (GC/LC-MS). Orthogonal partial least squares discriminant analysis (OPLS-DA), volcano diagrams and thermograms were used to distinguish metabolites. The attribute discriminators CfsSubsetEval combined with search method BestFirst in WEKA software was used to find the best predicted metabolite combinations, and then 24 classification methods with 10-fold cross-validation were used for prediction. 34 individuals were considered hypertensive combined with depression according to our criteria, and 34 subjects with hypertension only were matched according to age and sex. 19 metabolites by GC-MS and 65 metabolites by LC-MS contributed significantly to the differentiation between the depressed and non-depressed cohorts, with a VIP value of more than 1 and a P value of less than 0.05. There were multiple metabolic pathway alterations. The metabolite combinations screened with WEKA for optimal diagnostic value included 12 metabolites. The machine learning methods with AUC values greater than 0.9 were bayesNet and random forests, and their other evaluation measures are also better. Altered metabolites and metabolic pathways are present in older adults with hypertension combined with depression. Methods using metabolomics and machine learning performed quite well in predicting depression in hypertensive older adults, contributing to further clinical research.

Influence of sex, age, ethnicity/race, and body mass index on the cerumen volatilome using two data analysis approaches: binary and semiquantitative.

Human cerumen analysis is an innovative and non-invasive trend in diagnosing diseases. Recently, new cerumen volatile-based methods using binary (volatile presence/absence) and semiquantitative (volatile intensity) data approaches have shown great potential in detecting biomarkers for cancer, chronic and rare diseases, and xenobiotic exposures. However, to date, the impacts of demographic factors such as body mass index (BMI), sex, age, and ethnicity/race in cerumen data have not been widely described, which can hamper interpretation in biomarker discovery investigations. This study examined the effects of such factors in cerumen, defining the baseline volatile organic metabolites (VOMs) across different physiological groups. Cerumen samples from seventy volunteers were analyzed using headspace/gas chromatography-mass spectrometry (HS/GC-MS) and multivariate statistical analysis using binary and semiquantitative data approaches. In the binary data approach, several VOMs exhibited patterns of high occurrence in some specific demographic groups. However, no pattern of discrimination that could be attributed to demographic factors was observed. In the semiquantitative approach, the relative abundance of cerumen VOMs was more impacted by sex and BMI than age and ethnicity/race. In summary, we describe how cerumen VOM occurrence and abundance are affected by patient phenotype, which can pave the way for more personalized medicine in future cerumen volatile-based methods.

The effect of fires on the composition of aliphatic compounds in the steppe soils of Khakassia

The aim of the study was to assess the composition of aliphatic compounds in soils of post-pyrogenic territories of the steppe zone. Location and time of the study. Soil samples were collected from a depth of 0-1 cm (litter – steppe felt) and from a depth of 1-10 cm. three months after the fires at the undisturbed (control) and post-pyrogenic study sites in the Shirinsky district in the vicinity of the village (southern chernozem) and in the Ust-Abakan district near Ust-Abakan (southern chernozem) and Chernogorsk (chestnut soil). Methods. Organic compounds were isolated from dried and crushed soils by extraction with 7% methanol solution in chloroform. The composition of organic aliphatic compounds was determined by chromatography-mass spectrometry. Results. Hydrocarbons (n-alkanes), saturated and unsaturated fatty acids, ketones (n-alkane-2-ones, 10-nonacosanone, 16-gentriacontanone), n-aldehydes, alcohol 1-hexacosanol were found in the composition of soil aliphatic compounds. The total content of biomolecules in the upper soil layer of the control site was on average reduced by 82% compared to the litter. Under the influence of fire, there was a sharp decrease in the amount of n-aldehydes, fatty acids, and long-chain ketones in the litter, as compared with the undisturbed sites. The distribution of n-alkanes in soils was bimodal in nature: the first mode was represented by low–molecular even homologues C14–C22, common in microorganisms (mainly aerobic bacteria and fungi); the second mode was represented by the high–molecular odd structures C23-C35, indicating the contribution of terrestrial plants in soil organic matter. In the distribution of n-alkanes of soil felts after fires, an increase in the proportion of even low molecular mass homologues was found. In comparison with the control sites, a higher content of low molecular mass homologues was also characteristic of the n-aldehydes of the most litter samples of the of burnt areas. The fire affected the steppe felt and the topsoil itself to varying degrees. The initially low soil content of biomolecules and the distribution nature of the individual homologous series in burnt areas practically did not change as compared with the control sites. Thus, under the influence of fire, certain classes of biomolecules were destroyed, primarily those containing long paraffin chains. Later on, as a result of soil microbial activity, such compounds as low-molecular even n-alkanes are additionally formed. Conclusion. Analysis of aliphatic compounds composition in Khakassia steppe soils in the undisturbed and post-pyrogenic sites showed that biomarkers such as n-alkanes and n-aldehydes are environmental indicators of their sources, degradation processes, pyrogenic destruction and soil organic matter transformation.

Impact of complementary feeding on infant gut microbiome, metabolites and early development.

Introducing complementary foods is critical for promoting infant health and development. During the weaning period, the dietary patterns provide essential nutrients and facilitate the development of a diverse gut microbiome, which plays significant roles in the regulation of immune, metabolic, and neurological functions. This study enrolled 200 families to assess the impact of complementary feeding on infant growth and health outcomes. Data included detailed records of feeding practices, infant growth measurements, health assessments, and fecal samples and breast milk collected between weeks 12 and 32 postpartum. The gut microbiome was analyzed using 16S rRNA sequencing, while metabolites such as human milk oligosaccharides (HMOs), monosaccharides, and short-chain fatty acids (SCFAs) were measured using chromatography-mass spectrometry. Results revealed a high prevalence of breastfeeding, with complementary food introduced at around 16 weeks. Significant alterations in the infant gut microbiome were observed, particularly in the genera Lactobacillus, Akkermansia, and Staphylococcus. Additionally, the levels of HMOs, monosaccharides, and SCFAs were found to be influenced by the introduction of complementary foods. Significant correlations emerged between complementary feeding practices, gut microbiome diversity, specific bacterial genera (e.g., Streptococcus, Lactobacillus, Bifidobacterium, and Clostridioides), and key metabolites (such as lacto-N-tetraose, lacto-N-neotetraose, mannose, and butyric acid). This study offers valuable insights into the complex interactions between complementary feeding, gut microbiome development, and metabolite profiles during early infant growth. Future research with larger cohorts and targeted dietary interventions is recommended to further elucidate the underlying mechanisms.

Dietary liposomal complexes change the fatty acid composition of hepatic bioactive phospholipids in F1(C57blxDBA2\6) mice, as shown by a lipidomic approach.

Essential polyunsaturated fatty acids (PUFAs) of the n-3 and n-6 classes are crucial for maintaining many physiological functions of the human body. It has previously been suggested that the beneficial effects of n-3 PUFAs are mediated by the action of bioactive lipid components, although it remains unclear which specific lipids are metabolically active. The aim of this study was to assess the impact of various liposomal diets on the content and ratio of liver phospholipids, containing n-3 and n-6 PUFAs, in F1 (C57blxDBA2\6) mice. Lipidomic analysis using chromatography-mass spectrometry was employed to investigate changes in the fatty acid profile of liver phospholipids in six groups of mice. These mice were fed liposomal complexes of different compositions in drinks replacing water for a long-term diet (3 months). Two additional groups of mice, aged 2 and 5 months, were used as control groups. The six liposomal complexes included different combinations of phosphatidylcholine (PC), a natural antioxidant (clove bud essential oil (CEO)), fish oil (FO), and sodium caseinate (SC). The consumption of the PC-CEO-FO-SC liposomal complex significantly increased the amount of liver phospholipids containing n-3 docosahexaenoic acid, including phosphatidylcholines, phosphatidylethanolamines (PE), phosphatidylserines (PS), and lysophosphatidylcholine (LPC). This increase was accompanied by a marked decrease in the amount of phospholipids containing n-6 arachidonic acid. As a result, the weight ratio of phospholipids containing n-6 PUFAs to those containing n-3 PUFAs decreased significantly, especially for PC and PE subclasses. Therefore, the PC-CEO-FO-SC liposomal complex has the potential to enhance resistance to inflammation and reduce the risk of non-communicable diseases.

Содержание полициклических ароматических углеводородов в уличной пыли угледобывающего региона Южного Кузбасса

The relevance of the research is caused by the need to evaluate the content of polycyclic aromatic hydrocarbons (PAHs) formed during coal combustion. The object of the study is street dust of Mezhdurechensk (Kemerovo region). The purpose of the work is to assess the level of accumulation of the polyarenes. The subject is the determination of the 14 polyarenes content. Methodology and methods are as follows: the samples are selected according to the standard methodology of the areal network. The analysis has been carried out by chromatography-mass spectrometry. The following results are obtained: The average total PAH content is 2 148±364 mkg/kg, a maximum value is 4 011 mkg/kg and a minimum – 401 mkg/kg. The content of heavy PAHs (1 432±163 mkg/kg) is twice as high as the content of light PAHs (716±202 mkg/kg) and the percentage of benz(a)pyrene is 17,0–33,8 %, which is typical for territories where fuel is burned. The distribution of PAHs by granulometric fractions has showed the fairly uniform accumulation of PAHs in small (50–20 microns) and medium (100–50 microns) fractions and their predominance compared with large (1 000–100 microns) fractions: 43,5, 37,22, 19,63 % accordingly. The amount of PAHs expressed in equivalents of the most dangerous carcinogen benz(a)pyrene is 570±140 mkg/kg, and exceeded the MPC (20 mkg/kg) by an average of 28,5 times. The contribution of benz(a)pyrene to the total toxicity is 91 %. The authors conclude that the main sources of PAHs are their emission during coal combustion, their direct presence in coals, and to a lesser extent – the loss of petroleum products during transport.

Cancer evaluation in dogs using cerumen as a source for volatile biomarker prospection.

Cancer is one of the deadliest diseases in humans and dogs. Nevertheless, most tumor types spread faster in canines, and early cancer detection methods are necessary to enhance animal survival. Here, cerumen (earwax) was tested as a source of potential biomarkers for cancer evaluation in dogs. Earwax samples from dogs were collected from tumor-bearing and clinically healthy dogs, followed by Headspace/Gas Chromatography-Mass Spectrometry (HS/GC-MS) analyses and multivariate statistical workflow. An evolutionary-based multivariate algorithm selected 18 out of 128 volatile metabolites as a potential cancer biomarker panel in dogs. The candidate biomarkers showed a full discrimination pattern between tumor-bearing dogs and cancer-free canines with high accuracy in the test dataset: an accuracy of 95.0% (75.1-99.9), and sensitivity and specificity of 100.0% and 92.9%, respectively. In summary, this work raises a new perspective on cancer diagnosis in dogs, being carried out painlessly and non-invasive, facilitating sample collection and periodic application in a veterinary routine.

Study of Therapeutic Mechanisms of Bupi Yichang Formula against Colon Cancer Based on Network Pharmacology, Machine Learning, and Experimental Verification.

Bupi Yichang formula (BPYCF) has shown the anti-cancer potential; however, its effects on colon cancer and the mechanisms remain unknown. This study intended to explore the effects of BPYC on colon cancer and its underlying mechanisms. BPYCF-related and colon cancer-related targets were acquired from public databases, followed by differentially expressed genes (DEG) identification. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed using clusterProfiler. A protein-protein interaction (PPI) network was constructed using STRING database. CytoHubba and MCODE to screen the hub targets. A diagnostic model was built using random forest algorithm. Molecular docking was conducted using PyMOL and AutoDock. High-performance liquid chromatograph-mass spectrometry (HPLC-MS) analysis and in vitro validation were performed. Forty-six overlapping targets of BPYCF-related, colon cancer-related targets, and DEGs were obtained. GO and KEGG analyses showed that the targets were mainly enriched in response to lipopolysaccharide, neuronal cell body, protein serine/threonine/tyrosine, as well as C-type lectin receptor, NOD-like receptor, and TNF signaling pathways. Five targets were identified as the pivotal targets, among which, NOS3, CASP8, RIPK3, and TNFRSF10B were stably docked with the core active component, naringenin. Naringenin was also identified from the BPYCF sample through HPLC-MS analysis. In vitro experiments showed that BPYCF inhibited cell viability, reduced NOS3 expression, and elevated CASP8, RIPK3, and TNFRSF10B expression in colon cancer cells. BPYCF might treat colon cancer mainly by regulating NOS3, CASP8, RIPK3, and TN-FRSF10B. This study first revealed the therapeutic effects and mechanisms of BPYCF against colon cancer, paving the path for the development of targeted therapeutic strategies for this cancer in the clinic.

Detection of gluten peptides in human duodenal fluids with immuno-liquid chromatography-mass spectrometry.

Gluten proteins are storage proteins in wheat that exhibit a certain resistance to gastrointestinal digestion. To explore solutions to cope with accidental ingestion of gluten in individuals suffering from gluten-related disorders, it is essential to monitor the fate of gluten peptides in biological samples, i.e., gastrointestinal juices, blood plasma or urine. In this work, we aimed at developing a mass spectrometry (MS)-based method for measuring gluten peptides in human duodenal fluids. Seven gluten peptides, including the well-documented 33-mer gluten peptide (LQLQPFPQPQLPYPQPQLPYPQPQLPYPQPQPF), were selected after a literature review and characterization of a gluten-containing product. Isotopically labelled peptides were used as references and a targeted liquid chromatography (LC) MS assay based on high resolution parallel reaction monitoring (PRM) was designed. Despite iterative and fine tuning of the LC-PRM-MS method, the low level of endogenous gluten peptides in human duodenal fluid samples precluded their direct detection. Thus, an initial immunoprecipitation (IP) step was included. Several antibodies were tested, and one proved reliable for the enrichment of the 33-mer gluten peptide as well as a few additional gluten peptides. Figures-of-merits of the immuno-LC-PRM-MS assay were assessed with a focus on quantification trueness and precision. We have developed an MS-based method for measuring the 33-mer gluten peptide in human duodenal fluids. Based on isotopic dilution, the method relies on the combination of IP and LC-PRM-MS analysis. Measurements were shown to be sensitive, quantitative, and reproducible.

Depth distribution of nano- and microplastics and their contribution to carbon storage in Chinese agricultural soils

The extensive and prolonged utilization of plastic materials in agriculture has primarily led to the accumulation of nano- and microplastics (NMPs, ≤5 mm) in farmland soils. The spatial-vertical distribution of NMPs mass concentrations and their impact on the national agricultural soil carbon reservoir remain unexamined. In this study, we quantified the residual mass concentrations of six prevalent plastic types in farmland soils around China using the double-shot model of thermal desorption/pyrolysis-gas chromatography–mass spectrometry (TD/Py-GC–MS). The results showed that median NMPs concentrations were 79.81 μg/g in the topsoil layer (0–15 cm), 57.17 μg/g in the middle soil layer (15–30 cm), and 32.90 μg/g in the bottom soil layer (30–45 cm). Overall, agricultural soil NMPs levels declined from the surface to deeper soil layers; however, some regions exhibit an opposite trend. Furthermore, our estimations indicate that carbon sourced from NMPs contributes to the agricultural soil carbon pool within a range from 0.004 % to 5.606 %, depending on the soil depth. As a hallmark of sustainable agricultural soil management, it is noteworthy that the concealed and continuously expanding carbon contribution of NMPs has an impact on soil carbon storage, albeit at a relatively low level. Our data serves as a foundational reference point and enables a precise evaluation of future contributions of NMPs to the storage of carbon in agricultural soils within China.

Нові підходи до лікування отруєнь синтетичними опіоїдами: застосування великих доз Налоксону та перспективи створення альтернативних антидотів

Introduction. In the conditions of the spread of powerful synthetic opioids, the traditionally recommended doses of Naloxone may be insufficient; instead, a significant increase in the dose of Naloxone leads to side effects, which in turn creates a threat to life. Aim. Analysis of the results of own research and scientific information regarding the use of Naloxone in the treatment of synthetic opioids poisoning and the development of alternative antidotes. Materials and Methods. The medical data of 174 patients treated with the diagnosis: "Acute narcotic poisoning" (ICD-10:Т40.0-Т40.3) were studied. Laboratory studies were carried out by the method of immunochromatographic analysis and chromatographymass spectrometry. Statistical data processing was performed using the IBM SPSS Statistics 29.0.0.0 program, using Spearman's rank correlation analysis (r), with p ≤ 0.05. Results. Among patients who received Naloxone, the best dynamics according to the Glasgow coma scale at the 4th and 6th hours of observation were those who received 2-6 mg of Naloxone. A significant part of patients (76 cases, 43.68 %) required repeated administration of Naloxone due to the renarcotization, in such cases a direct correlation was established with the occurrence of undesirable clinical effects (r = 0.864, p = 0.05). A direct relationship between an increase in the dose of Naloxone and the development of arterial hypertension (r = 0.945, p = 0.01), convulsions (r = 0.887, p = 0.01), withdrawal and pain syndrome (r = 0.881, p = 0.01). In general, the occurrence of clinical effects was correlated with an increase in the dose of Naloxone (R2 = 0.92), however, the rank correlation analysis did not confirm the relationship between the dose of Naloxone and the development of pulmonary edema (r = 0.938, p > 0.05), cardiac arrhythmia (r= 0.598, p > 0.05), cardiac arrest (r= -0.146, p > 0.05). Conclusions. The use of high doses of Naloxone does not solve the problem of prevention of opioid overdoses and their effective treatment. The development of new models of antidotes to opioids using сovalent Naloxone nanoparticles, serotonin 5-HT1A agonists, Fentanyl-binding Cyclodextrin scaffolds, specific vaccines, etc. is considered promising. Keywords: opioids, antidotes, Naloxone, Fentanyl.

Method Development for Aminopyralid Residues Determination by Ultra-High-Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry in Straw

Straw is an important by-product of crop production. It has been widely used as a feed as well as in fruit–vegetable production due to exerting a positive impact on soil and crop health and quality in the operated areas. On the other hand, applied crop-specific herbicides throughout the production stage, like aminopyralid (AP), may lead to significant plant injuries in sensitive vegetable plantations, even in very low concentrations. This study aims to optimize a short time, minimal consumables needed, and sensitive extraction and analytical method for AP residues in straw material using LC-MS/MS. For this purpose, standard AP signal response in acetonitrile (MeCN) and 1% of formic acid (FA) in methanol (MeOH) were tested; several chromatographic separation and mass spectroscopy (MS) parameters were improved and optimized. Subsequently, two different extraction methods were performed in AP spiked straw samples, and extraction efficacies were compared. Salting-out assisted liquid–liquid extraction (SALLE) by acidified MeCN combined with final dissolution in MeOH with 1% of FA prior to the analysis was chosen as the most appropriate method for the straw matrix. This method was then used for validation and real sample test analysis. The limit of quantification (LOQ) of AP in this optimized extraction method achieved 10 ng/g straw with a recovery rate of 71% and 13% RSD. The method was also tested on field straw mulch samples and 22.54 ± 0.8 ng/g of AP was detected.

Berberine Mediates the Production of Butyrate to Ameliorate Cerebral Ischemia via the Gut Microbiota in Mice.

Ischemic stroke (IS) is a vascular disease group concomitant with high morbidity and mortality. Berberine is a bioactive substance and it has been known to improve stroke, but its mechanism is yet to be proven. Mice were fed with BBR for 14 days. Then, the mice were made into MCAO/R models. Neurological score, infarct volume, neuronal damage and markers associated with inflammation were detected. We tested the changes in intestinal flora in model mice after BBR administration using 16SrRNA sequencing. Chromatography-mass spectrometry was used to detect butyrate chemically. Tissue immunofluorescence was used to detect the changes in the microglia and astroglia in the mice brains. Our findings suggest that berberine improves stroke outcomes by modulating the gut microbiota. Specifically, after MCAO/R mice were given berberine, the beneficial bacteria producing butyric acid increased significantly, and the mice also had significantly higher levels of butyric acid. The administration of butyric acid and an inhibitor of butyric acid synthesis, heptanoyl-CoA, showed that butyric acid improved the stroke outcomes in the model mice. In addition, butyric acid could inhibit the activation of the microglia and astrocytes in the brains of model mice, thereby inhibiting the generation of pro-inflammatory factors IL-6, IL-1β and TNF-α as well as improving stroke outcomes. Our results suggest that berberine may improve stroke outcomes by modulating the gut flora to increase the abundance of butyric acid. These findings elucidate the mechanisms by which berberine improves stroke outcomes and provide some basis for clinical treatment.

An Automated Centrifugal Microfluidic Platform for Efficient Multistep Blood Sample Preparation and Clean-Up towards Small Ion-Molecule Analysis.

Sample preparation for mass spectroscopy typically involves several liquid and solid phase clean-ups, extractions, and other unit operations, which are labour-intensive and error-prone. We demonstrate a centrifugal microfluidic platform that automates the whole blood sample's preparation and clean-up by combining traditional liquid-phase and multiple solid-phase extractions for applications in mass spectroscopy (MS)-based small molecule detection. Liquid phase extraction was performed using methanol to precipitate proteins in plasma separated from a blood sample under centrifugal force. The preloaded solid phase composed of C18 beads then removed lipids with a combination of silica particles, which further cleaned up any remaining proteins. We further integrated the application of this sample prep disc with matrix-assisted laser desorption/ionization (MALDI) MS by using glancing angle deposition films, which further cleaned up the processed sample by segregating the electrolyte background from the sample salts. Additionally, hydrophilic interaction liquid chromatography (HILIC) MS was employed for detecting targeted free amino acids. Therefore, several representative ionic metabolites, including several amino acids and organic acids from blood samples, were analysed by both MALDI-MS and HILIC-MS to demonstrate the performance of this sample preparation disc. The fully automated blood sample preparation procedure only took 35 mins, with a throughput of three parallel units.