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Garlic (Allium sativum L.) is an important vegetable crop throughout the world. In Greece there are many areas which have specialized in garlic cultivation through the last decades, considered the main production areas. However, despite the significance of garlic as a food product and the high annual income of this crop, there is a decreasing trend in total cultivated area in Greece, and the local landraces are gradually neglected in favor of new imported genotypes. In the present study, garlic genotypes (local landraces/varieties, imported genotypes, commercial cultivars) from the main production regions of Greece were assessed for their chemical composition and quality (total soluble solids, dry matter content, nutritional value, mineral composition, organic acids, fatty acids content and free sugars content), and bulb morphology. The results of the present study showed significant diversity in quality features and bulb morphology, not only between the genotypes from different growing regions, but also between those of the same region. This result is interesting since it could be implemented for further improvement and valorization of this important vegetable crop through extensive breeding programs within the framework of sustainability and genetic, material conservation.

Fruit from rosaceous species collectively display a great variety of flavors and textures as well as a generally high content of nutritionally beneficial metabolites. However, relatively little analysis of metabolic networks in rosaceous fruit has been reported. Among rosaceous species, peach (Prunus persica) has stone fruits composed of a juicy mesocarp and lignified endocarp. Here, peach mesocarp metabolic networks were studied across development using metabolomics and analysis of key regulatory enzymes. Principal component analysis of peach metabolic composition revealed clear metabolic shifts from early through late development stages and subsequently during postharvest ripening. Early developmental stages were characterized by a substantial decrease in protein abundance and high levels of bioactive polyphenols and amino acids, which are substrates for the phenylpropanoid and lignin pathways during stone hardening. Sucrose levels showed a large increase during development, reflecting translocation from the leaf, while the importance of galactinol and raffinose is also inferred. Our study further suggests that posttranscriptional mechanisms are key for metabolic regulation at early stages. In contrast to early developmental stages, a decrease in amino acid levels is coupled to an induction of transcripts encoding amino acid and organic acid catabolic enzymes during ripening. These data are consistent with the mobilization of amino acids to support respiration. In addition, sucrose cycling, suggested by the parallel increase of transcripts encoding sucrose degradative and synthetic enzymes, appears to operate during postharvest ripening. When taken together, these data highlight singular metabolic programs for peach development and may allow the identification of key factors related to agronomic traits of this important crop species.

Enantiomeric excess of chiral compounds is a key parameter that determines their activity or therapeutic action. The current paradigm for rapid measurement of enantiomeric excess using NMR is based on the formation of diastereomeric complexes between the chiral analyte and a chiral resolving agent, leading to (at least) two species with no symmetry relationship. Here we report an effective method of enantiomeric excess determination using a symmetrical achiral molecule as the resolving agent, which is based on the complexation with analyte (in the fast exchange regime) without the formation of diastereomers. The use of N,N′-disubstituted oxoporphyrinogen as the resolving agent makes this novel method extremely versatile, and appropriate for various chiral analytes including carboxylic acids, esters, alcohols and protected amino acids using the same achiral molecule. The model of sensing mechanism exhibits a fundamental linear response between enantiomeric excess and the observed magnitude of induced chemical shift non-equivalence in the 1 H NMR spectra. The enantiopurity of chiral compounds is key in determining their activity or therapeutic action. Here, the authors present a versatile NMR method of enantiomeric excess determination using a symmetrical achiral molecule as resolving agent, based on complexation with analyte, without formation of diastereomers.

The benzene polycarboxylic acid (BPCA) method is a technique to characterise the aromaticity and aromatic condensation of pyrogenic carbon (PyC) in charred residues. As a molecular marker for polycondensed aromatic moieties, the analysis of BPCAs in archaeological contexts has great potential as a means of detecting and characterising charred residues where past fire traces are not evident. Despite the increased frequency of applications and significant developments since the method's inception, no central database of BPCA results for modern charcoal pyrolysed under controlled laboratory conditions exists. Limited sample sizes in previous research have restricted the ability to precisely quantify the effects of combustion temperature, precursor feedstocks, pyrolysis parameters (e.g., oxygen availability), and methodological aspects (e.g., chromatography) on resultant BPCA profiles. To remedy this, we present the BPChAr database, which contains a total of 236 BPCA results on modern lab-produced charcoal. Through statistical analyses of the gathered data, we quantify the relationship between combustion temperature and resultant BPCA profiles, and construct random forest models to predict combustion temperature in unknown samples. Our findings show that additional variables hypothesised to play a role in shaping BPCA results - such as precursor feedstock type, oxygen availability during pyrolysis, and chromatographic separation method - have statistically significant implications for resultant BPCA profiles. Our analysis nuances these observations, highlighting at what charring temperatures and for what variables these concomitant parameters should be factored into the interpretation of BPCA results. Random forest models are also developed to predict precursor feedstock (hardwoods, softwoods, and grasses) in unknown samples, though further work is required to refine the accuracy of this model. The BPChAr database constitutes a fundamental tool for modern PyC research, and provides a baseline for future work aimed at employing the BPCA method in palaeoenvironmental and archaeological research.

A simple and robust analytical method for the determination of perfluorinated carboxylic acids (PFCAs) with C 2 to C 8 chains, based on solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), was developed, validated and applied to tap water, groundwater and surface water. Two stationary phases for LC (Obelisc N and Kinetex C 18 ) and two materials with weak anion-exchange properties for SPE (Strata X-AW and Oasis WAX) were evaluated. Robust separation and retention was achieved with the reversed phase column and an acidic eluent. Quantitative extraction recoveries were generally achieved for PFCAs with C > 3, but extraction efficiencies were different for the two shortest chained analytes: 36 to 114% of perfluoropropanoate (PFPrA) and 14 to 99% of trifluoroacetate (TFA) were recovered with Strata X-AW, while 93 to 103% of PFPrA and 40 to 103% of TFA were recovered with Oasis WAX. The sample pH was identified as a key parameter in the extraction process. One-step elution-filtration was introduced in the workflow, in order to remove sorbent particles and minimise sample preparation steps. Validation resulted in limits of quantification for all PFCAs between 0.6 and 26 ng/L. Precision was between 0.7 and 15% and mean recoveries ranged from 83 to 107%. In groundwater samples from sites impacted by per- and polyfluoroalkyl substances (PFASs), PFCA concentrations ranged from 0.056 to 2.2 μg/L. TFA and perfluorooctanoate were the predominant analytes. TFA, however, revealed a more ubiquitous occurrence and was found in concentrations between 0.045 and 17 μg/L in drinking water, groundwater and surface water, which were not impacted by PFASs.

BackgroundRecently, problems associated with proton pump inhibitor (PPI) use have begun to surface. PPIs influence the gut microbiota; therefore, PPI use may increase the risk of enteric infections and cause bacterial translocation. In this study, we investigated fecal microbiota composition, fecal organic acid concentrations and pH, and gut bacteria in the blood of the same patients before and after PPI use.MethodsTwenty patients with reflux esophagitis based on endoscopic examination received 8 weeks of treatment with PPIs. To analyze fecal microbiota composition and gut bacteria in blood and organic acid concentrations, 16S and 23S rRNA-targeted quantitative RT-PCR and high-performance liquid chromatography were conducted.ResultsLactobacillus species were significantly increased at both 4 and 8 weeks after PPI treatment compared with bacterial counts before treatment (P = 0.011 and P = 0.002, respectively). Among Lactobacillus spp., counts of the L. gasseri subgroup, L. fermentum, the L. reuteri subgroup, and the L. ruminis subgroup were significantly increased at 4 and 8 weeks after treatment compared with counts before treatment. Streptococcus species were also significantly increased at 4 and 8 weeks after PPI treatment compared with counts before treatment (P < 0.01 and P < 0.001, respectively). There was no significant difference in the total organic acid concentrations before and after PPI treatment. Detection rates of bacteria in blood before and after PPI treatment were 22 and 28%, respectively, with no significant differences.ConclusionsOur quantitative RT-PCR results showed that gut dysbiosis was caused by PPI use, corroborating previous results obtained by metagenomic analysis.

The quality attributes of jujube fruit can be directly and indirectly affected by abiotic stresses associated with climate change. Increased temperature and drought are among the most important factors challenging sustainable jujube production in the temperate semi-arid region in northwest China. The main objective of the present study was to understand the effects of elevated air temperature and drought stress on sugar and acid accumulation and coloration of jujube fruits. The content of soluble sugar, organic acid and pigments of traditional jujube \"Linwuchangzao\" under different atmospheric temperatures and drought stresses were analyzed during three different fruit ripening stages. The elevated temperature (1.5–2.5° C than normal temperature) significantly increased the fruit sugar content, sugar-acid ratio, anthocyanins, flavonoids and carotenoids content. Under the drought stress where the soil moisture was 30% -50% of the field capacity, sugar content, anthocyanin, flavonoid and carotenoid content of the fruit were significantly reduced at the same temperature, but the chlorophyll and organic acid content increased. No significant interaction of Temperature x Drought was observed for all the analyzed quality parameters. The current results showed that the fruit quality of jujube variety \"Lingwuchangzao\" could be improved when the atmospheric temperature increases by 2° C in this region. However, drought stress had a negative impact on the fruit's sugar-acid ratio and pigment content. The present results also showed that the synthesis and accumulation of anthocyanins in jujube fruit were positively correlated with sugar content and related enzyme activities, especially Phenylalanine Ammonia-lyase (PAL) activity. This study, therefore, provides novel information for understanding the influence of growth environment on the quality properties of jujube fruits. This knowledge will help develop appropriate crop management practices for jujube production in arid and semi-arid areas in northwest China.

Carboxyl-bearing low-molecular-weight compounds such as keto acids, fatty acids, and other organic acids are involved in a myriad of metabolic pathways owing to their high polarity and solubility in biological fluids. Various disease areas such as cancer, myeloid leukemia, heart disease, liver disease, and lifestyle diseases (obesity and diabetes) were found to be related to certain metabolic pathways and changes in the concentrations of the compounds involved in those pathways. Therefore, the quantification of such compounds provides useful information pertaining to diagnosis, pathological conditions, and disease mechanisms, spurring the development of numerous analytical methods for this purpose. This review article addresses analytical methods for the quantification of carboxylic acids, which were classified into fatty acids, tricarboxylic acid cycle and glycolysis-related compounds, amino acid metabolites, perfluorinated carboxylic acids, α-keto acids and their metabolites, thiazole-containing carboxylic acids, and miscellaneous, in biological samples from 2000 to date. Methods involving liquid chromatography coupled with ultraviolet, fluorescence, mass spectrometry, and electrochemical detection were summarized.

Background Exposure to perfluorinated-alkyl-acids (PFAAs) is ubiquitous. PFAAs are hormone-disrupting compounds that are strongly suspected to affect mother-child-health such as fetal growth. Thyroid disruption is a plausible mechanism of action. We aim to summarize the epidemiological evidence for the relation between prenatal and postnatal exposure to PFAAs and disruption of thyroid homeostasis in mothers and/or infants. Method Fifteen original publications on PFAAs concentrations and thyroid hormones (TH) in pregnant women and/or infants were found upon a literature search in the PubMed database. Information on exposure to seven PFAAs congeners [Perfluorooctane sulfonate (PFOS), Perfluorooctanoate (PFOA), Perfluorohexane sulfonate (PFHxS), Perfluorononanoic acid (PFNA), Perfluorodecanoic acid (PFDA), Perfluoroundecanoic acid (PFUnA), and Perfluorododecanoic acid (PFDoA)] and thyroid stimulating hormone (TSH), free and total thyroxine (FT4 and TT4), free and total triiodothyronine (FT3 and TT3), T3RU (Free triiodothyronine resin uptake) and FT4-index (FT4I) levels were recorded. We evaluated sampling of maternal TH by trimester, and infant TH by sex stratification. Reported associations between mother or infant PFAAs and TH were not uniformly assessed in the selected studies. Results Ten out of the fifteen studies examined maternal PFAAs concentration and TSH level. Seven studies showed significant associations between TSH and exposure to six PFAAs congeners, most of them were positive. Maternal T4 and T3 were investigated in nine studies and five studies found inverse associations between exposure to six PFAAs congeners and TH (TT3, TT4, FT3, FT4 and FT4I) levels. Eight of the fifteen studies investigated PFAAs concentrations and infant TSH. Infant TSH level was significantly affected in four studies, positively in three studies. Nine studies investigated infant T4 and T3 and seven studies found significant associations with PFAAs exposure. However, both inverse and positive significant associations with infant TH were found eliciting no clear direction. Conclusion Results indicate a mainly positive relationship between maternal PFAAs concentrations and TSH levels, and suggestion of an inverse association with T4 and/or T3 levels. Associations of infant TH with PFAAs concentration were less consistent.

Summary Staphylococcus aureus is a Gram‐positive human pathogen that is readily internalized by professional phagocytes such as macrophages and neutrophils but also by non‐professional phagocytes such as epithelial or endothelial cells. Intracellular bacteria have been proposed to play a role in evasion of the innate immune system and may also lead to dissemination within migrating phagocytes. Further, S. aureus efficiently lyses host cells with a battery of cytolytic toxins. Recently, phenol‐soluble modulins (PSM) have been identified to comprise a genus‐specific family of cytolytic peptides. Of these the PSMα peptides have been implicated in killing polymorphonuclear leucocytes after phagocytosis. We questioned if the peptides were active in destroying endosomal membranes to avoid lysosomal killing of the pathogen and monitored integrity of infected host cell endosomes by measuring the acidity of the intracellular bacterial microenvironment via flow cytometry and by a reporter recruitment technique. Isogenic mutants of the methicillin‐resistant S. aureus (MRSA) strains USA300 LAC, USA400 MW2 as well as the strongly cytolytic methicillin‐sensitive strain 6850 were compared with their respective wild type strains. In all three genetic backgrounds, PSMα mutants were unable to escape from phagosomes in non‐professional (293, HeLa, EAhy.926) and professional phagocytes (THP‐1), whereas mutants in PSMβ and δ‐toxin as well as β‐toxin, phosphatidyl inositol‐dependent phospholipase C and Panton Valentine leucotoxin escaped with efficiencies of the parental strains. S. aureus replicated intracellularly only in presence of a functional PSMα operon thereby illustrating that bacteria grow in the host cell cytoplasm upon phagosomal escape. Staphylococcus aureus is efficiently taken up by mammalian cells but escapes the phagosome in an agr quorum sensing‐controlled process. Clinical strains of S. aureus use PSMα, small amphiphilic peptides, to escape the phagosome and subsequently switch off quorum sensing‐dependent transcription. S. aureus further replicates within the cytoplasm but not in the phagosome of its host cells. Phagosomal escape of S. aureus therefore marks a decisive phase in intracellular staphylococcal infections, which may constitute the basis for host cell death.