High-resolution Mass Spectrometry Analysis Research Articles

Anti-breast cancer potential activity of Phaleria macrocarpa (Scheff.) Boerl. leaf extract through in silico studies

Context: The development of apoptotic agent from natural plant products may have a beneficial effect as a promising candidate for cancer therapy. The study about the efficacy of Phaleria macrocarpa leaves on breast cancer is still limited. Aims: To elucidate the molecular mechanisms underlying the anti-breast cancer activity of P. macrocarpa leaves extract by in silico analysis. Methods: The compounds of the ethanol extract of P. macrocarpa were identified by Liquid Chromatography–High Resolution Mass Spectrometry (LC-HRMS) analysis. Fourteen bioactive compounds of P. macrocarpa leaf were analyzed to determine the biological activity using Prediction of Activity Spectra for Substances (PASS) server. The network analysis was analyzed using STRING (https://string-db.org/). Twelve selected compounds were docked with several protein targets, including caspase 3, Bax and Bcl-2. Molecular docking was done by Pyrx 0.8 software and visualized by Discovery Studio software. The pharmacological properties of investigated bioactive compounds were analyzed using the SwissADME web server. Results: The twelve from fourteen bioactive compounds of P. macrocarpa leaf have anticancer properties and might be expected to involve in p53 and PI3K/Akt signaling pathways related to cancer. The molecular docking result showed that sesamin from the lignans group has the best binding affinity to caspase-3 and Bax. Meanwhile, corymboside from the flavonoid group has the best binding affinity to Bcl-2. Conclusions: The bioactive compounds of P. macrocarpa leaves extract might potentially modulate apoptosis and cell growth. Further research should be performed to validate the activity of P. macrocarpa bioactive compounds for target cancer development.

High-Resolution Mass Spectrometry and Nontraditional Mass Defect Analysis of Brominated Historical Pigments.

The implementation of high-resolution mass spectrometry systems offers new possibilities for the analysis of complex art samples such as historical oil paintings. However, these multicomponent systems generate large and complex data sets that require advanced visualization tools to aid interpretation, especially when no chromatographic separation is performed. In the context of this research, it was crucial to propose a data analysis tool to identify the products generated during the synthesis, drying, and aging of historical pigments. This study reports for the first time a nontraditional mass defect analysis of oil paint samples containing a fugitive brominated-organic pigment, eosin or geranium lake, by using direct infusion electrospray ionization in combination with a high-resolution Orbitrap mass spectrometer. The use of nontraditional Kendrick mass defect plots is presented in this study as a processing and visualization tool to recognize brominated species based on their specific mass defect and isotope pattern. The results demonstrate that this approach could provide valuable molecular compositional information on the degradation pathways of this pigment. We anticipate that mass defect analysis will become highly relevant in future degradation studies of many more historical organic pigments.

Multispectroscopic and molecular modeling strategy to explore the interaction of cholest-5-en-7-one with human serum albumin: DFT and Hirshfeld surface analysis

The present study accounts for cholest-5-en-7-one (steroid) synthesis using selenium dioxide and silica as well as its identification using high-resolution mass spectrometry (HRMS), FT-IR, NMR, and elemental analysis. Density functional theory (DFT) calculations were used to optimize the steroid's geometry, which was then compared to single-crystal X-ray diffraction data, indicating that the computational and experimental results were in good agreement. UV–vis absorption titration, fluorescence spectral methods, circular dichroism (CD), and dynamic light scattering (DLS)were used to investigate the well-identified steroid's in vitro molecular interaction with human serum albumin (HSA).The results and binding parameter indicate that the steroid has significant binding affinity for HSA. Molecular docking was performed and found that the steroid can interact with the hydrophobic cavity of HSA through hydrogen and hydrophobic contacts. Molecular dynamics simulation was used to confirm the stability of the HSA-steroid complex. Combined quantum mechanics-molecular mechanics (QM-MM) methods were applied to know binding energy of system and individual components for atomic level interactions indicating a significant interaction between the steroid and the biomacromolecules. The findings presented here contribute to a better understanding of steroid pharmacodynamics.

Aqueous photodegradation of the benzophenone fungicide metrafenone: Carbon-bromine bond cleavage mechanism

Metrafenone (MF), as a new type of benzophenone fungicide, has been widely used in agriculture and is persistent in the environment. Understanding its photochemical fate is essential for the comprehensive evaluation of its ecological risk. In the present work, we reported a detailed study on the photochemical transformation of MF in aqueous solution under irradiation (at λ > 290 nm using a high pressure mercury lamp). MF was relatively photo-reactive showing a low polychromatic quantum yield of photolysis (1.06 × 10−4, 20 µM) counterbalanced by a significant light absorption above 290 nm. A series of photoproducts were identified by high resolution mass spectrometry (HR-MS) analysis, and three different pathways, including oxidation of the methyl group, debromination and replacement of bromine by hydroxyl group were proposed. Among them, debromination was identified as the dominating process that could be achieved via homolytic C-Br bond cleavage from singlet and triplet MF, as confirmed by laser flash photolysis (LFP) experiments and density functional theory (DFT) calculations. Toxicity assessment revealed that photochemical degradation reduced the ecotoxicity of MF efficiently. Nitrate ions and humic acid promoted the MF photolysis, while bicarbonate exhibited no effect. Results obtained in this work would increase our understanding on the environmental fate of MF in sunlit surface waters.

Non-thermal plasma coupled with MOx/γ-Al2O3 (M: Fe, Co, Mn, Ce) for chlorobenzene degradation: Analysis of byproducts and the reaction mechanism

Chlorinated volatile organic compounds (VOCs) such as chlorobenzene pose serious human health and environmental risks, but are resistant to elimination techniques that are traditionally applied to Cl-free VOCs. Non-thermal plasma (NTP) offers a promising technique to decompose chlorobenzene, but its application remains limited owing to low COx selectivity and the generation of toxic byproducts. To address these problems, this study investigated chlorobenzene degradation in NTP coupled with MOx/γ-Al2O3 (M: Fe, Co, Mn, Ce) catalysts. The combination of NTP with MOx/γ-Al2O3 remarkably improved the removal efficiency (RE), mineralization rate (MR), Cl selectivity (SCl) and energy yield (EY) of chlorobenzene abatement, and decreased the production of residual O3. CoOx/γ-Al2O3 exhibited the best performance among these tested catalysts with higher RE, MR, SCl and EY by 26.06%, 25.52%, 33.03% and 2.41 g/kWh, respectively, at 510 J/L, compared with those of the NTP alone system. Several catalyst characterizations were applied to explore the relation between the catalyst characteristics and chlorobenzene abatement efficacy in NTP. The results indicate that the NTP catalytic oxidation of chlorobenzene strongly depends on the reducibility and acidity of the MOx/γ-Al2O3 samples, whereas the textural properties of the catalysts exert a limited influence on chlorobenzene degradation. High-resolution gas chromatography and high-resolution mass spectrometry analyses verified for the first time that PCDD/Fs were generated during chlorobenzene degradation in NTP catalytic reactions. A plausible decomposition mechanism of chlorobenzene in the NTP catalytic system is speculated according to the organic intermediates generated during chlorobenzene decomposition.

Fatty acids and their derivatives from Chlorella vulgaris extracts exhibit in vitro antimicrobial activity against the honey bee pathogen Paenibacillus larvae

The green microalga Chlorella vulgaris Beijerinck (Chlorellaceae) is widely used as a food supplement for humans and animals. In beekeeping practice, Chlorella vulgaris has potential as a pollen supplement. We studied whether Chlorella extracts display antimicrobial properties against Paenibacillus larvae, the causative agent of the honey bee bacterial disease American foulbrood. We identified components responsible for antimicrobial activity and evaluated the added values of Chlorella as a food supplement for honey bees. Different extracts (water, acetone, methanol) were prepared from Chlorella biomass (phototrophically and heterotrophically cultivated) and screened for antimicrobial activity against ERIC I and ERIC II genotypes of P. larvae. Active acetone extracts of phototrophically cultivated Chlorella vulgaris biomass were fractioned via preparative reverse-phase chromatography. Antimicrobial activity was detected for 9 of the resulting 33 fractions. Further analysis revealed the chemical composition of the active fractions. C. vulgaris extracts showed a significant antimicrobial effect against vegetative cells and spores of P. larvae strains of ERIC I and ERIC II genotypes. The lowest MIC of the most active acetone extract was 6.3 µg/mL for both tested genotypes. In the majority of the active fractions, monolinolenin, fatty acid linoleic acid, and methyl esters of linoleic and/or palmitic acid were identified via high-performance liquid chromatography coupled with high-resolution mass spectrometry analysis. Based on our results, we concluded that algal C. vulgaris food supplements not only contain nutritional but also potential prophylactic properties for honey bee health.

Biotransformation of Flavonoids Improves Antimicrobial and Anti-Breast Cancer Activities In Vitro.

Coarse cereals are rich in flavonoids, which are bioactive substances with a wide range of functions. Biotransformation is considered an emerging approach to methylate flavonoids, displaying prominent regio- and stereoselectivity. In the current study, liquiritigenin, naringenin, and hesperidin flavonoids were biotransformed using O-methyltransferases that were heterologously expressed in Saccharomyces cerevisiae BJ5464-NpgA. Nuclear magnetic resonance (NMR) spectroscopy was used together with high-resolution mass spectroscopy analysis to determine the structures of the resulting methylated transformants, and their antimicrobial and antiproliferation activities were also characterized. Among the five methylated flavonoids obtained, 7-methoxy-liquiritigenin had the strongest inhibitory effect on Candida albicans SC5314 (C. albicans SC5314), Staphylococcus aureus ATCC6538 (S. aureus ATCC6538), and Escherichia coli ATCC25922 (E. coli ATCC25922), which increased 7.65-, 1.49-, and 0.54-fold in comparison to the values of their unmethylated counterparts at 200, 250, and 400 μM, respectively. The results suggest that 3′-methoxyhesperetin showed the best antiproliferative activity against MCF-7 cells with IC50 values of 10.45 ± 0.45 µM, which was an increase of more than 14.35-fold compared to that of hesperetin. These results indicate that methylation enhances the antimicrobial activities and antiproliferative effects of flavonoids. The current study provides an experimental basis for further research on flavonoids as well as flavonoid-containing crops in the development of antimicrobial and anti-breast cancer drugs in addition to supplementary and health foods. The biotransformation method is ideal, as it represents a means for the sustainable production of bioactive flavonoids.

UV and (V)UV irradiation of sitagliptin in ultrapure water and WWTP effluent: Kinetics, transformation products and degradation pathway

Sitagliptin (SITA) is an antidiabetic drug consumed worldwide in high quantities. Because of the low removal rate of this compound in conventional wastewater treatment plants (WWTPs), it enters receiving surface waters with the discharged WWTP effluents. SITA can be detected up to μg/L concentration in rivers. In this study, UV (254 nm) and (V)UV (185 nm + 254 nm) irradiation was applied in laboratory scale to degrade SITA. The effect of three parameters was evaluated on the degradation rate, namely i) the efficiency in UV and (V)UV irradiation, ii) the presence or absence of dissolved oxygen, iii) the matrix effect of WWTP effluent. Degradation rate of SITA was largely increased by (V)UV irradiation, and decreased in WWTP effluent as expected. The presence of dissolved oxygen increased the degradation rate only in UV experiments and did not have a considerable effect in (V)UV experiments. In total, 14 transformation products (TPs) were identified (twelve new); their structures were proposed based on high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy analyses. The most characteristic reaction steps of the degradation of SITA involved nucleophilic aromatic photosubstitution whereas hydroxide ions acted as attacking nucleophiles and replaced F atoms of the phenyl moiety by hydroxide groups, in agreement with the increase in photolysis rate with increasing pH. The photochemical degradation pathway of SITA was also interpreted. Kinetic profiles revealed TP 421, TP 208 and TP 192 to be the most recalcitrant TPs.

A scalable workflow to characterize the human exposome

Complementing the genome with an understanding of the human exposome is an important challenge for contemporary science and technology. Tens of thousands of chemicals are used in commerce, yet cost for targeted environmental chemical analysis limits surveillance to a few hundred known hazards. To overcome limitations which prevent scaling to thousands of chemicals, we develop a single-step express liquid extraction and gas chromatography high-resolution mass spectrometry analysis to operationalize the human exposome. We show that the workflow supports quantification of environmental chemicals in human plasma (200 µL) and tissue (≤100 mg) samples. The method also provides high resolution, sensitivity and selectivity for exposome epidemiology of mass spectral features without a priori knowledge of chemical identity. The simplicity of the method can facilitate harmonization of environmental biomonitoring between laboratories and enable population level human exposome research with limited sample volume.

Diversity of Carbonyl Compounds in Biogas and Natural Gas Revealed Using High-Resolution Mass Spectrometry and Nontarget Analysis

Airborne carbonyl compounds such as formaldehyde, acrolein, and methyl ethyl ketone have long been chemicals-of-concern in the environment due to their reactivity and their potential for negative health effects. Standard methods for determining carbonyls in air, which focus on a set of 15 or fewer compounds, involve derivatization to form nonvolatile hydrazones, which can readily be analyzed via liquid chromatography (LC) with ultraviolet detectors. Here, we apply a new LC-high-resolution mass spectrometry (HRMS) method to natural gas and a variety of upgraded biofuels to better assess their total carbonyl profile using the inherent selectivity of the standard sampling methodology and the selectivity and sensitivity of HRMS. The standard method accounted for only 64% of the total carbonyl content in natural gas and between 26 and 45% of the total carbonyl content in biogas sources, with the balance detected by the new LC/HRMS method. An additional 540 compounds with molecular formulas consistent with carbonyl compounds were detected compared to only 14 target compounds using the standard method. These results demonstrate that the established method dramatically under-reports both the total carbonyl load and the diversity of carbonyl species in natural gas and biogas samples.

A Fully Integrated Online Platform For Real Time Monitoring Of Multiple Product Quality Attributes In Biopharmaceutical Processes For Monoclonal Antibody Therapeutics

In response to FDA's call for Quality by Design (QbD) in biopharmaceutical product development, the biopharmaceutical industry has been developing highly sensitive and specific technologies in the monitoring and controlling of product quality attributes for bioprocesses. We previously published the successful application of an off-line multi-attribute method (MAM) to monitor more than 20 critical quality attributes (CQA) with superior sensitivity for the upstream process. To further remove the hurdles of laborious process sampling and sample preparation associated with the offline method, we present here a fully integrated MAM based online platform for automated real time online process monitoring. This integrated system includes Modular Automated Sampling Technology (MAST) based aseptic sampling, multi-function Sequential Injection Analysis (SIA) sample preparation, UHPLC separation and high-resolution mass spectrometry (HRMS) analysis. Continuous automated daily monitoring of a 17-day cell culture process was successfully demonstrated for a model monoclonal antibody (mAb) molecule with similar specificity and sensitivity as we reported earlier. To the best of our knowledge, this is the first report of an end-to-end automated online MAM system, which would allow the MAM to be applied to routine bioprocess monitoring, potentially replacing multiple conventional low resolution and low sensitivity off-line methods. The online HPLC or HPLC/MS platform could be easily adapted to support other processing steps such as downstream purification with minimal software re-configuration.

Isolation and characterization of new phenolic siderophores with antimicrobial properties from Pseudomonas sp. UIAU-6B.

Five new phenolic siderophores 1–5 were isolated from the organic extract of a culture broth in a modified SGG medium of Pseudomonas sp. UIAU-6B, obtained from sediments collected from the Oyun river in North Central Nigeria. The structure of the new compounds, pseudomonin A–C (1–3) and pseudomobactin A and B (4 and 5) isolated alongside two known compounds, pseudomonine (6) and salicylic acid (7), were elucidated based on high-resolution mass spectrometry, 1D and 2D NMR analyses. The absolute configuration of the threonine residue in compounds 1–5 was determined by Marfey analysis. The antimicrobial evaluation of compound 4 exhibited the most potent activity against vancomycin-sensitive Enterococcus faecium VS144754, followed by 3 and 5, with MIC values ranging from 8 to 32 µg/mL. Compounds 2 and 3 exhibited moderate activity against Mycobacterium tuberculosis H37Rv, with MIC values of 7.8 and 15.6 µg/mL, respectively. Plausible biosynthetic hypotheses toward the new compounds 1–5 were proposed.

α-glucosidase inhibitors from Syzygium polyanthum (Wight) Walp leaves as revealed by metabolomics and in silico approaches

Ethnopharmacological relevanceSyzygium polyanthum (Wight) Walp leaves are traditionally used to cure diabetes in many regions of Indonesia. Traditional use involves boiling the leaves until the water is reduced to half volume, and then the decoction is taken 1–2 times daily. Despite several studies reporting the antidiabetic activity of this plant, bioactive compounds have not been well identified. Aim of the studyIndonesia is one of the countries with the highest diabetes cases, particularly type 2 diabetes mellitus (T2DM). Few people have access to modern medicinal treatment; thus, the role of antidiabetic traditional medicine has become increasingly important. This research aimed to identify α-glucosidase inhibitors from S. polyathum leaves using a metabolomics approach. When the active compounds of S. polyathum are properly identified, the quality of the herb can be more easily controlled. Materials and methodsThe dried leaves of S. polyanthum were extracted by a comprehensive extraction method using a solvent combination of n-hexane, acetone, and water in a gradient, resulting in a total of 42 fractions. All fractions were subjected to an in vitro α-glucosidase inhibition test and chemical profile analysis using Nuclear Magnetic Resonance (NMR) and high performance liquid chromatography (HPLC). Orthogonal projection least square (OPLS) analysis was used to correlate the two data to identify NMR signals, and HPLC chromatogram peaks correlated to the activity. 2D NMR and ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS) analyses were also used to give more precise compound identification. The activity of the identified active compounds was confirmed by an in silico technique. Results and discussionThe results of the α-glucosidase activity test showed that the most active fractions were obtained from solvents with medium polarity: Fractions 9 and 10 (F9 and F10), obtained from gradient acetone-water 4:1 and 3:2, respectively. The IC50 values of F9 and F10 were 24.8 and 31.8 μg/mL, respectively. NMR data showed that F9 had more intense and diverse signals in the aromatic region than F10. OPLS analysis results showed that some typical flavonoid signals abundant in F9 positively correlated with α-glucosidase activity. 2D NMR and UHPLC-HRMS analysis of F9 led to the conclusion that these signals could be attributed to myricetin-3-O-rhamnoside (myricitrin) and epigallocatechin-3-gallate (EGCG). In silico analysis confirmed these results, as myricitrin and EGCG had binding energies resembling acarbose as a positive control (-8.47, -8.19, and -10.13, respectively). ConclusionsNMR and HPLC-metabolomics successfully identified myricitrin and EGCG as α-glucosidase inhibitors from S. polyanthum leaves, and docking analysis validated their inhibitory activity. The results of this study justified the traditional use of S. polyanthum as an antidiabetes herbal.

Advanced Analytical Study of Process Streams for a Rational Optimization of Hydrothermal Gasification

Hydrothermal processes are promising technologies for an efficient valorization of wet biomass feedstocks or wastes. Their performance strongly depends on the composition of the feedstock, and methods to analyze such complex mixtures along with the produced effluents are in constant progress. Herein, catalytic hydrothermal gasification (cHTG) was used to valorize process water produced from the hydrothermal liquefaction of pine wood. A detailed analysis of the effluents and streams at various points of the process was performed. About 54% of the feed’s chemical energy could be transferred to synthetic natural gas while an excellent extraction of minerals (98%) into a concentrated brine (27 wt % dry matter) could be achieved. The low gasification efficiency observed and the origin of the 41% and 44% loss of chemical energy and carbon in the brine, respectively, were investigated by high-pressure liquid chromatography–high-resolution mass spectrometry (HPLC–HRMS) analysis of the feed and the effluents from the salt separator. This allowed for identifying mono- and polycarboxylates accounting for 71% of the carbon in the brine. Increasing temperature in the salt separator to favor decarboxylation reaction was identified as pivotal to improve synthetic natural gas yields, with a 20-fold decrease of carboxylate concentration being reached with a temperature rise from 723 to 768 K. The use of two new approaches to estimate the high heating value (HHV) of this feed rich in volatile organic compounds is also reported.

Phytochemical Screening and Potential Antibacterial Activity of Defatted and Nondefatted Methanolic Extracts of Xao Tam Phan (Paramignya trimera (Oliv.) Guillaum) Peels against Multidrug-Resistant Bacteria.

Xao tam phan (Paramignya trimera (Oliv.) Guillaum) is a traditional herbal medicine in Vietnam. Previous investigations reported mainly compounds and bioactivities of roots, stems, and leaves while there is limited information about those of fruits. This study aims to reveal the difference in the chemical profile of defatted peel (DP) and nondefatted peel (NDP) methanolic extracts of P. trimera using colorimetric reactions and liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS) analysis. We also showed the potential antibacterial activity of two extracts against clinically isolated bacteria strains including P. aeruginosa, Salmonella sp., and S. aureus with the MIC values < 100 μg/mL. This preliminary result proves the traditional usage of this herbal medicine and can be helpful for further investigation on the isolation and identification of the new compounds in P. trimera peels.

Altered Proteomic Profile of Adipose Tissue-Derived Mesenchymal Stem Cell Exosomes from Cats with Severe Chronic Gingivostomatitis

Simple SummaryFeline chronic gingivostomatitis (FCGS) is a common pathology in cats, related to an aberrant immune response. The cause of FCGS remains elusive, despite extensive investigations. A multitude of conditions and infectious agents have been related, without proof of causation, as follows: virus, bacteria, environmental stress, hypersensitivity, etc. In recent years, therapies based on feline adipose-derived mesenchymal stem cells (fAd-MSC) have become an interesting alternative for the treatment of different complex pathologies in cats. Mesenchymal stem cells secrete a wide variety of therapeutic elements, such as bioactive molecules and extracellular vesicles, such as exosomes. It is essential to characterize these elements, to better understand their mechanisms of action. In this study, we show, for the first time, that the proteomic profile of fAd-MSC-derived exosomes, from calicivirus-positive patients with severe FCGS, is altered. Using bioinformatic tools, we have demonstrated the existence of different proteins in the exosomes from diseased patients, responsible for an altered biological effect. In addition, the exosomes do not only experience changes in their cargo, but are also produced in larger quantities. This study might contribute to the better prediction of the clinical outcomes of mesenchymal stem cell treatments in veterinary patients with immune-mediated diseases, such as FCGS.Feline chronic gingivostomatitis (FCGS) is a pathology with a complicated therapeutic approach and with a prevalence between 0.7 and 12%. Although the etiology of the disease is diverse, feline calicivirus infection is known to be a predisposing factor. To date, the available treatment helps in controlling the disease, but cannot always provide a cure, which leads to a high percentage of refractory animals. Mesenchymal stem cells (MSCs) play a pivotal role in the homeostasis and reparation of different tissues and have the ability to modulate the immune system responses. This ability is, in part, due to the capacity of exosomes to play a part in intercellular cell communication. However, the precise role of MSC-derived exosomes and their alterations in immunocompromised pathologies remains unknown, especially in veterinary patients. The goal of this work was to analyze the proteomic profile of feline adipose tissue-derived MSCs (fAd-MSCs) from calicivirus-positive FCGS patients, and to detect possible modifications of the exosomal cargo, to gain better knowledge of the disease’s etiopathogenesis. Using high-resolution mass spectrometry and functional enrichment analysis with Gene Ontology, exosomes isolated from the fAd-MSCs of five healthy cats and five calicivirus-positive FCGS patients, were pooled and compared. The results showed that the fAd-MSCs from cats suffering from FCGS not only had a higher exosome production, but also their exosomes showed significant alterations in their proteomic profile. Eight proteins were exclusively found in the exosomes from the FCGS group, and five proteins could only be found in the exosomes from the healthy cats. When comparing the exosomal cargo between the two groups, significant upregulation of 17 and downregulation of 13 proteins were detected in the FCGS group compared to the control group. These findings shed light on new perspectives on the roles of MSCs and their relation to this disease, which may help in identifying new therapeutic targets and selecting specific biomarkers.

An Aggregation-Induced Emission Optical Highlighter for the Studies of Endoplasmic Reticulum-Lipid Droplet Content Dynamics

An Aggregation-Induced Emission Optical Highlighter for the Studies of Endoplasmic Reticulum-Lipid Droplet Content Dynamics

In Vitro Bioaccessibility and Antioxidant Activity of Polyphenolic Compounds from Spent Coffee Grounds-Enriched Cookies.

Spent coffee ground (SCG) is a significant by-product generated by the coffee industry. It is considered a great source of bioactive molecules well-recognized for exerting biological properties. This study aimed to implement SCG in a baked foods, such as cookies (SCGc), to increase their bioactive potential. A comprehensive study of the polyphenolic fraction of the SCG and SCGc using a high-resolution mass spectrometry analysis was performed. Moreover, the polyphenol bioaccessibility and change in antioxidant activity during simulated gastrointestinal digestion (GiD) were assessed. Data showed that SCGc provided 780 mg of melanoidins, 16.2 mg of chlorogenic acid (CGA), 6.5 mg of caffeine, and 0.08 mg of phenolic acids per 100 g of sample. Moreover, the 5-caffeoylquinic acid was the most relevant CGA found in SCG (116.4 mg/100 g) and SCGc (8.2 mg/100 g) samples. The antioxidant activity evaluated through three spectrophotometric tests, and the total phenolic compounds of SCGc samples exhibited significantly higher values than the control samples. Furthermore, during simulated GiD, the highest bioaccessibility of SCGc polyphenols was observed after the colonic stage, suggesting their potential advantages for human health. Therefore, SCG with high content in bioactive molecules could represent an innovative ingredient intended to fortify baked food formulations.

Bacterial Enrichment Cultures Biotransform the Mycotoxin Deoxynivalenol into a Novel Metabolite Toxic to Plant and Porcine Cells.

The mycotoxin deoxynivalenol (DON), produced in wheat, barley and maize by Fusarium graminearum and Fusarium culmorum, is threatening the health of humans and animals. With its worldwide high incidence in food and feed, mitigation strategies are needed to detoxify DON, maintaining the nutritional value and palatability of decontaminated commodities. A promising technique is biological degradation, where microorganisms are used to biotransform mycotoxins into less toxic metabolites. In this study, bacterial enrichment cultures were screened for their DON detoxification potential, where DON and its potential derivatives were monitored. The residual phytotoxicity was determined through a bioassay using the aquatic plant Lemna minor L. Two bacterial enrichment cultures were found to biotransform DON into a still highly toxic metabolite for plants. Furthermore, a cytotoxic effect was observed on the cellular viability of intestinal porcine epithelial cells. Through liquid chromatography high-resolution mass spectrometry analysis, an unknown compound was detected, and tentatively characterized with a molecular weight of 30.0 Da (i.e., CH2O) higher than DON. Metabarcoding of the subsequently enriched bacterial communities revealed a shift towards the genera Sphingopyxis, Pseudoxanthomonas, Ochrobactrum and Pseudarthrobacter. This work describes the discovery of a novel bacterial DON-derived metabolite, toxic to plant and porcine cells.

Anaerobic biotransformation mechanism of marine toxin domoic acid

Domoic acid (DA) is a major marine neurotoxin, occurs frequently in most of the world’s coastlines and seriously threatens ecosystem and public health. However, information on its biotransformation process in coastal anaerobic environments remains unclear. In this study, the underlying mechanism of anaerobic biotransformation of DA by marine consortium GLY was investigated using the combination of liquid chromatography–high-resolution Orbitrap mass spectrometry and comparative metatranscriptomics analysis. The results demonstrated that DA could be cometabolically biotransformed under anaerobic conditions with pseudo-first-order reaction. Anaerobic biotransformation pathway of DA was clarified, including decarboxylation, dehydrogenation, carboxylation activation with CoA and multiple β-oxidation steps occurring at aliphatic side chain, which facilitated DA detoxification. Furthermore, anaerobic cometabolic biotransformation mechanism of glycine-DA by consortium GLY was established for the first time, a number of genes related to the metabolic pathways of glycine fermentation, fatty acid synthesis and β-oxidation were responded in the consortium GLY transcriptome and involved in the anaerobic biotransformation of DA. This study could deepen understanding of interaction mechanism between toxin DA and marine microorganisms, which provides a new insight into the DA fate and its effects on benthic microbial community in marine environments.