Identification Of Metabolites Research Articles

Non-targeted discovery of high-value bio-products in Nicotiana glauca L: a potential renewable plant feedstock

The evaluation of plant-based feedstocks is an important aspect of biorefining. Nicotiana glauca is a solanaceous, non-food crop that produces large amounts of biomass and is well adapted to grow in suboptimal conditions. In the present article, compatible sequential solvent extractions were applied to N. glauca leaves to enable the generation of enriched extracts containing higher metabolite content comparing to direct leaf extracts. Typically, between 60 to 100 metabolite components were identified within the fractions. The occurrence of plant fatty acids, fatty acid alcohols, alkanes, sterols and terpenoids was detected by gas liquid chromatography–mass spectrometry (GC–MS) and metabolite identification was confirmed by comparison of physico-chemical properties displayed by available authentic standards. Collectively, co-products such waxes, oils, fermentable sugars, and terpenoids were all identified and quantified. The enriched fractions of N. glauca revealed a high level of readily extractable hydrocarbons, oils and high value co-products. In addition, the saccharification yield and cell wall composition analyses in the stems revealed the potential of the residue material as a promising lignocellulosic substrate for the production of fermentable sugars. In conclusion a multifractional cascade for valuable compounds/commodities has been development, that uses N. glauca biomass. These data have enabled the evaluation of N. glauca material as a potential feedstock for biorefining.Graphical

Structural Identification of Ginsenoside Based on UPLC-QTOF-MS of Black Ginseng (Panax Ginseng C.A. Mayer).

Black ginseng (BG) is processed ginseng traditionally made in Korea via the steaming and drying of ginseng root through three or more cycles, leading to changes in its appearance due to the Maillard reaction on its surface, resulting in a dark coloration. In this study, we explored markers for differentiating processed ginseng by analyzing the chemical characteristics of BG. We elucidated a new method for the structural identification of ginsenoside metabolites and described the features of processed ginseng using UPLC-QTOF-MS in the positive ion mode. We confirmed that maltose, glucose, and fructose, along with L-arginine, L-histidine, and L-lysine, were the key compounds responsible for the changes in the external quality of BG. These compounds can serve as important metabolic markers for distinguishing BG from conventionally processed ginseng. The major characteristics of white ginseng, red ginseng, and BG can be distinguished based on their high-polarity and low-polarity ginsenosides, and a precise method for the structural elucidation of ginsenosides in the positive ion mode is presented.

Screening of Secondary Metabolites Produced by Nigrospora sphaerica Associated with the Invasive Weed Cenchrus ciliaris Reveals Two New Structurally Related Compounds.

In the search for new alternative biocontrol strategies, phytopathogenic fungi could represent a new frontier for weed management. In this respect, as part of our ongoing work aiming at using fungal pathogens as an alternative to common herbicides, the foliar pathogen Nigrospora sphaerica has been evaluated to control buffelgrass (Cenchrus ciliaris). In particular, in this work, the isolation and structural elucidation of two new biosynthetically related metabolites, named nigrosphaeritriol (3-(hydroxymethyl)-2-methylpentane-1,4-diol) and nigrosphaerilactol (3-(1-hydroxyethyl)-4-methyltetrahydrofuran-2-ol), from the phytotoxic culture filtrate extract were described, along with the identification of several known metabolites. Moreover, the absolute stereochemistry of (3R,4S,5S)-nigrosphaerilactone, previously reported as (3S,4R,5R)-4-hydroxymethyl-3,5-dimethyldihydro-2-furanone, was determined for the first time by X-ray diffraction analysis. Considering their structural relationship, the determination of the absolute stereochemistry of nigrosphaerilactone allowed us to hypothesize the absolute stereochemistry of nigrosphaeritriol and nigrosphaerilactol.

Pharmacokinetic study of osilodrostat and identification of mono-hydroxylated metabolite in equine plasma for the purpose of doping control.

Osilodrostat is an inhibitor of 11-beta-hydroxylase (CYP11B) and is used for the treatment of Cushing's disease but also categorized as an anabolic agent. The use of osilodrostat is prohibited in horseracing and equestrian sports. To the best of our knowledge, this is the first metabolic study of osilodrostat in equine plasma. Potential metabolites of osilodrostat were identified by differential analysis using data acquired from pre- and post-administration plasma samples after protein precipitation with liquid chromatography electrospray ionization high-resolution mass spectrometry (LC/ESI-HRMS). [Correction added on 27 January 2023, after first online publication: In the preceding sentence, "C-HRMS" was changed to "LC/ESI-HRMS" in this version.] For quantification of osilodrostat, a strong cation exchange solid-phase extraction was employed, and the extracts were analyzed using LC/ESI-triple quadrupole tandem mass spectrometry (LC/ESI-QqQ-MS/MS)to establish its elimination profile. Such extracts were further analyzed using LC/ESI-HRMS to investigate the detectability of osilodrostat and its identified mono-hydroxylated metabolite over a 2-week sampling period. Mono-hydroxylated osilodrostat was identified based on the differential analysis and mass spectrometric interpretations, and it was found to be the most abundant metabolite in plasma. Elimination profile of osilodrostat in plasma was successfully established over the 24-h post-administration period. Both osilodrostat and its mono-hydroxylated metabolite were detected up to the last sampling point at 2weeks using HRMS, and osilodrostat could be confirmed up to 8-day post-administration with its reference material using HRMS as well. For doping control, screening of both the parent drug osilodrostat and its mono-hydroxylated metabolite in equine plasma would be recommended due to their extended detection windows of up to 2weeks. Given the availability of reference material for potential confirmation in forensic samples, osilodrostat is considered the most appropriate monitoring target.

Comparative Analysis of Phytochemical Profiles and Selected Biological Activities of Various Morphological Parts of Ligustrum vulgare.

Ligustrum vulgare (LV), widely cultivated in Europe and often used in hedges, has been historically recognized in folk medicine for its potential health benefits. This study focused on exploring the untargeted identification of secondary metabolites in ethanol extracts (70% v/v) from different morphological parts (young shoots, leaves, flowers and fruits) of LV at various stages of plant development, using ultra-high-performance liquid chromatography with high-resolution mass spectrometry (UHPLC-HRMS). Additionally, the selected biological activities (antioxidant activity, cyclooxygenase-2 inhibition (COX-2), α-amylase inhibition and cytotoxicity) of the tested extracts were determined. Untargeted metabolomics showed that LV extracts were a rich source of phenylethanoid compounds, flavonoids, iridoids and their derivatives. The flowers of LV had the highest content of oleuropein (33.43 ± 2.48 mg/g d.w.). The lowest antioxidant activity was obtained for ripe and post-seasonal fruits, while in the case of other samples, the activity was at a similar level. All tested extracts showed α-amylase and COX-2 inhibitory activity. In addition, LV extracts showed strong antiproliferative properties in colorectal (HT29) and liver (HepG2) cancer cell lines. The obtained results show the difference in the content of bioactive compounds in various morphological parts of Ligustrum vulgare. These differences may influence the multifaceted medicinal potential of this plant.

Evaluation of the Drug-Induced Liver Injury Potential of Saxagliptin through Reactive Metabolite Identification in Rats.

A liver injury was recently reported for saxagliptin, which is a dipeptidyl peptidase-4 (DPP-4) inhibitor. However, the underlying mechanisms of saxagliptin-induced liver injury remain unknown. This study aimed to evaluate whether saxagliptin, a potent and selective DPP-4 inhibitor that is globally used for treating type 2 diabetes mellitus, binds to the nucleophiles in vitro. Four DPP-4 inhibitors, including vildagliptin, were evaluated for comparison. Only saxagliptin and vildagliptin, which both contain a cyanopyrrolidine group, quickly reacted with L-cysteine to enzyme-independently produce thiazolinic acid metabolites. This saxagliptin-cysteine adduct was also found in saxagliptin-administered male Sprague-Dawley rats. In addition, this study newly identified cysteinyl glycine conjugates of saxagliptin and 5-hydroxysaxagliptin. The observed metabolic pathways were hydroxylation and conjugation with cysteine, glutathione, sulfate, and glucuronide. In summary, we determined four new thiazoline-containing thiol metabolites (cysteine and cysteinylglycine conjugates of saxagliptin and 5-hydroxysaxagliptin) in saxagliptin-administered male rats. Our results reveal that saxagliptin can covalently bind to the thiol groups of cysteine residues of endogenous proteins in vivo, indicating the potential for saxagliptin to cause drug-induced liver injury.

Identification of blood metabolites associated with risk of Alzheimer's disease by integrating genomics and metabolomics data.

Specific metabolites have been reported to be potentially associated with Alzheimer's disease (AD) risk. However, the comprehensive understanding of roles of metabolite biomarkers in AD etiology remains elusive. We performed a large AD metabolome-wide association study (MWAS) by developing blood metabolite genetic prediction models. We evaluated associations between genetically predicted levels of metabolites and AD risk in 39,106 clinically diagnosed AD cases, 46,828 proxy AD and related dementia (proxy-ADD) cases, and 401,577 controls. We further conducted analyses to determine microbiome features associated with the detected metabolites and characterize associations between predicted microbiome feature levels and AD risk. We identified fourteen metabolites showing an association with AD risk. Five microbiome features were further identified to be potentially related to associations of five of the metabolites. Our study provides new insights into the etiology of AD that involves blood metabolites and gut microbiome, which warrants further investigation.

Detection of FG-4592 and metabolites in equine plasma, urine and hair following oral administration.

FG-4592 is a hypoxia-inducible factor inhibitor that has been approved for therapeutic use in some countries. This class of compounds can increase the oxygen carrying capacity of the blood and thus have the potential to be used as performance enhancing agents in sports. The purpose of this study was to investigate the detection of FG-4592 and metabolites in equine plasma and mane hair following a multiple dose oral administration to two Thoroughbred racehorses, to identify the best analytical targets for doping control laboratories. Urine samples were also analysed, and the results compared to previously published urine data. Liquid chromatography-high resolution mass spectrometry was used for metabolite identification in urine and plasma. Liquid chromatography-tandem mass spectrometry was used for full sample analysis of urine, plasma and hair samples and generation of urine and plasma profiles. FG-4592 and a mono-hydroxylated metabolite were detected in plasma. FG-4592 was detected with the greatest abundance and gave the longest duration of detection, up to 312 h post-administration, and would be the recommended target in routine doping samples. FG-4592 was detected in all mane hair samples collected post-administration, up to 166 days following the final dose, showing extended detection can be achieved with this matrix. To the best of the authors' knowledge, this is the first report of FG-4592 and metabolites in equine plasma and hair samples. Urine results were consistent with the previously published data, with FG-4592 offering the best target for detection and longest detection periods.

Machine learning of cellular metabolic rewiring.

Metabolic rewiring allows cells to adapt their metabolism in response to evolving environmental conditions. Traditional metabolomics techniques, whether targeted or untargeted, often struggle to interpret these adaptive shifts. Here, we introduce MetaboLiteLearner, a lightweight machine learning framework that harnesses the detailed fragmentation patterns from electron ionization (EI) collected in scan mode during gas chromatography/mass spectrometry to predict changes in the metabolite composition of metabolically adapted cells. When tested on breast cancer cells with different preferences to metastasize to specific organs, MetaboLiteLearner predicted the impact of metabolic rewiring on metabolites withheld from the training dataset using only the EI spectra, without metabolite identification or pre-existing knowledge of metabolic networks. Despite its simplicity, the model learned captured shared and unique metabolomic shifts between brain- and lung-homing metastatic lineages, suggesting cellular adaptations associated with metastasis to specific organs. Integrating machine learning and metabolomics paves the way for new insights into complex cellular adaptations.

Polyketides/nonribosomal peptides from Streptococcus mutans and their ecological roles in dental biofilm.

Streptococcus mutans is the major etiological agent of dental caries in humans. S. mutans overgrowth within dental biofilms can trigger biofilm dysbiosis, ultimately leading to the initiation or progression of dental caries. Polyketides and nonribosomal peptides (PKs/NRPs) are secondary metabolites with complex structures encoded by a cluster of biosynthetic genes. Although not essential for microbial growth, PKs/NRPs play important roles in physiological regulation. Three main classes of hybrid PKs/NRPs in S. mutans have been identified, including mutanobactin, mutanocyclin, and mutanofactin, encoded by the mub, muc, and muf gene clusters, respectively. These three hybrid PKs/NRPs play important roles in environmental adaptation, biofilm formation, and interspecies competition of S. mutans. In this review, we provide an overview of the major hybrid PKs/NRPs of S. mutans, including mutanobactin, mutanocyclin, and mutanofactin and address their ecological roles in dental biofilms. We place specific emphasis on important questions that are yet to be answered to provide novel insights into the cariogenic mechanism of S. mutans and facilitate improved management of dental caries. We highlight that S. mutans PKs/NRPs may be potential novel targets for the prevention and treatment of S. mutans-induced dental caries. The development of genomics, metabolomics, and mass spectrometry, together with the integration of various databases and bioinformatics tools, will allow the identification and synthesis of other secondary metabolites. Elucidating their physicochemical properties and their ecological roles in oral biofilms is crucial in the identification of novel targets for the ecological management of dental caries.

Synergetic Multichiral Covalent Organic Framework for Enantioselective Recognition and Separation.

In enantiomer recognition and separation, a highly enantioselective approach with universal applicability is urgently desired but hard to realize, especially in the case of chiral molecules. To resolve the trade-off between enantioselectivity and universality, a glutathione (GSH) and methylated cyclodextrins (MCD)-functionalized covalent organic framework (GSH-MCD COF) with porosity and abundant chiral surfaces is presented that was designed and synthesized for recognition and separation of various enantiomers. As expected, the GSH-MCD COF can be used as chiral stationary phases for the separation of various enantiomers, including aromatic alcohols, aromatic acids, amides, amino acids, and organic acids, with performance and versatility even superior to some widely used commercial chiral chromatographic columns. Furthermore, the synthesized GSH-MCD COF shows high enantioselectivity for the rapid recognition and identification of enantiomers and chiral metabolites when coupling to Raman spectroscopy. Molecular simulations suggest that the COF provides a confined microenvironment for cyclodextrins and peptides that dictates the separation and recognition capability. This work provides a strategy to synthesize synergetic multichiral COF and achieve separations and recognitions of enantiomers in complex samples.

Simultaneously quantification of eight marker compounds by HPLC, and HPTLC analysis for the marker-based shelf-life kinetic study for the standardization of polyherbal drug AYUSH SG-5, medicinal properties and computational studies

The herbal or alternative medicines having their own significances in each country. The major problem behind the non-acceptance of the alternative medicines is the poor standardization and quality control. Maximum times, it’s impossible to quantify the complex matrix of polyherbal medicines. The pharmacopeial standards of these medicines are limited to physicochemical and pharmacognostic analysis only, which are insufficient for the proper quality control of ingredients used for the preparation of polyherbal formulations. Multi-markers-based analysis of alternative medicines and their polyherbal formulations by using the sophisticated analytical techniques like HPLC, and LC-MS is the demand of current scenario. In our recent report we have reported pharmaceutical standard operating procedure for a coded polyherbal formulation (CPF i.e. AYUSH-SG-5) which was prepared for the rheumatoid arthritis. The marker-based quantification and identification of major metabolites and shelf-life (marker-based) studies were not reported in that study. In this report we have quantified eight markers (6-Gingerol, 8-Gingerol, Guggulsterone-E, Guggulsterone-Z, Resveratrol, Salicin, Colchicine, and Caffeic acid) simultaneously by HPLC chromatography. To identify the phytochemicals in polyherbal formula (CPF), LC-QTOF-MS/MS analysis was performed, where 32 main phytochemicals were identified out of 80 peaks. In herbal industry, HPTLC is the main tool for drug quantification, so we have reported a HPTLC method for the real time shelf-life study. In HPTLC study, we have used three major markers (6-Gingerol, Guggulsterone-E, Guggulsterone-Z) that are reproducible in hydroalcoholic extract and not in aqueous and methanolic extracts of CPF. The kinetic study-based shelf-life of CPF formulation was performed, the observed shelf-life of CPF was more than 41 months. In addition, evaluation of antioxidant activity like total phenolic (TPC), total flavonoid (TFC) and DPPH assays were performed, and results exhibited that hydroalcoholic extract having more values than aqueous and methanolic extracts of CPF. The phytochemicals observed in LC-QTOF-MS/MS studies were tested for in silico anti-inflammatory activity and anti-arthritic activities, which need to be explored after the detailed pharmacological and biological studies. Overall, analytical studies result of present study could use to standardize the CPF as well as the all relevant polyherbal formulations where these raw drugs have been used.

1H NMR Serum Metabolomic Change of Trimethylamine N-oxide (TMAO) Is Associated with Alcoholic Liver Disease Progression.

Without early detection and treatment, chronic and excessive alcohol consumption can lead to the development of alcoholic liver disease (ALD). With this in mind, we exploit the recent concept of the liver-gut axis and analyze the serum profile of ALD patients for identification of microbiome-derived metabolites that can be used as diagnostic biomarkers for onset of ALD. 1H-NMR was used to analyze serum metabolites of 38 ALD patients that were grouped according to their Child-Turcotte-Pugh scores (CTP): class A (CTP-A; 19), class B(CTP-B; 10), and class C (CTP-C; 9). A partial least squares-discriminant analysis (PLS-DA) and a variable importance of projection (VIP) score were used to identify significant metabolites. A receiver operating characteristic (ROC) curve and correlation heatmap were used to evaluate the predictability of identified metabolites as ALD biomarkers. Among 42 identified metabolites, 6 were significantly correlated to exacerbation of ALD. As ALD progressed in CTP-C, the levels of trimethylamine N-oxide (TMAO), malate, tyrosine, and 2-hydroxyisovalerate increased, while isobutyrate and isocitrate decreased. Out of six metabolites, elevated levels of TMAO and its precursors (carnitine, betaine, choline) were associated with severity of ALD. This indicates that TMAO can be used as an effective biomarker for the diagnosis of ALD progression.

Identification of the main flavonoids of Abelmoschus manihot (L.) medik and their metabolites in the treatment of diabetic nephropathy.

Introduction: Huangkui capsule (HKC) is made from the ethanol extract of Abelmoschus manihot (L.) Medik [Malvaceae; abelmoschi corolla] and received approval from the China Food and Drug Administration (Z19990040) in 1999. Currently, HKC is used for treatment of the patients with diabetic nephropathy (DN) in China. The bioactive chemical constituents in HKC are total flavonoids of A. manihot (L.) Medik (TFA). The present study aims to identify the primary flavonoid metabolites in HKC and TFA and their metabolism fates in db/db mice, the animal model for the study of type 2 diabetes and DN. Methods: HKC (0.84g/kg/d) and TFA (0.076g/kg/d) or vehicle were respectively administered daily via oral gavage in db/db mice for 4 weeks. The metabolism fate of the main metabolites of HKC in serum, liver, kidney, heart, jejunum, colon, jejunal contents, colonic contents, and urine of db/db mice were analyzed with a comprehensive metabolite identification strategy. Results and Discussion: In db/db mice administered with HKC and TFA, 7 flavonoid prototypes and 38 metabolites were identified. The related metabolic pathways at Phases I and II reactions included dehydroxylation, deglycosylation, hydrogenation, methylation, glucuronidation, sulphation, and corresponding recombined reactions. Quercetin, isorhamnetin, quercetin sulphate, quercetin monoglucuronide, and isorhamnetin monoglucuronide presented a high exposure in the serum and kidney of db/db mice. Thereby, the present study provides a pharmacodynamic substance basis for better understanding the mechanism of A. manihot (L.) Medik for medication of DN.

Benzo(k)fluoranthene and benzo(b)fluoranthene degradation by Selenastrum capricornutum and identification of metabolites using HPLC-FD and HPLC-ESI-QqQ-MS/MS

Selenastrum capricornutum efficiently degrades high molecular weight polycyclic aromatic hydrocarbons (HMW PAHs). Until now, there are few studies on the benzo(k)fluoranthene (BkF) and benzo(b)fluoranthene (BbF) biodegradation by this microalga. For this reason, in the present work, extracts obtained from cultures of S. capricornutum were incubated with BkF and BbF individually, and analyzed by HPLC with fluorescence and different mass spectrometry detection modes: i) the HPLC-ESI(+)-MS/MS (MRM mode) analysis that confirmed the formation of monohydroxylated and dihydrodiol metabolites indicating that these PAHs could be simultaneously degraded through the monooxygenase and dioxygenase; ii) HPLC-ESI(+)-MS (full scan mode) that showed the formation of key metabolites containing four and two aromatic rings possibly resulting from aromatic ring-opening oxygenases, not known until now in microalgae; iii) HPLC-FD analysis that confirmed the individual BkF and BbF degradation occurring in extra- and intra-cellular extracts, indicating that an oxygenase enzyme complex is released by microalgae cells to the external environment to perform HMW PAHs biodegradation. So, this work presents new insights into the metabolic pathways of BkF and BbF biodegradation by S. capricornutum; likewise, the intra- and extra-cellular extracts of this microalgae have great potential to be applied in environmental procedures.

Emerging Perfluorobutane Sulfonamido Derivatives as a New Trend of Surfactants Used in the Semiconductor Industry.

The semiconductor industry has claimed that perfluorooctanesulfonate (PFOS), a persistent per- and polyfluoroalkyl substance (PFAS), has been eliminated from semiconductor production; however, information about the use of alternative compounds remains limited. This study aimed to develop a nontarget approach to discovering diverse PFAS substitutions used in semiconductor manufacturing. A distinct fragment-based approach has been established to identify the hydrophobic and hydrophilic features of acidic and neutral fluorosurfactants through fragments and neutral losses, including those outside the homologous series. Ten sewage samples from 5 semiconductor plants were analyzed with target and nontarget analysis. Among the 20 identified PFAS spanning 12 subclasses, 15 were reported in semiconductor sewage for the first time. The dominant identified PFAS compounds were C4 sulfonamido derivatives, including perfluorobutane sulfonamido ethanol (FBSE), perfluorobutane sulfonamide (FBSA), and perfluorobutane sulfonamido diethanol (FBSEE diol), with maximum concentrations of 482 μg/L, 141 μg/L, and 83.5 μg/L in sewage, respectively. Subsequently, three ultrashort chain perfluoroalkyl acids (PFAAs) were identified in all samples, ranging from 0.004 to 19.9 μg/L. Three effluent samples from the associated industrial wastewater treatment plants (WWTPs) were further analyzed. This finding, that the C4 sulfonamido acetic acid series constitutes a significant portion (65%-82%) of effluents from WWTP3 and WWTP4, emphasizes the conversion of fluorinated alcohols to fluorinated acids during aerobic treatment. The identification of the intermediate metabolites of FBSEE diol, further supported by our laboratory batch studies, prompts the proposal of a novel metabolic pathway for FBSEE diol. The total amount of perfluorobutane sulfonamido derivatives reached 1934 μg/L (90%), while that of PFAAs, which have typically received attention, was only 205 μg/L (10%). This suggests that perfluorobutane sulfonamido derivatives are emerging as a new trend in fluorosurfactants used in the semiconductor industry, serving as PFAS precursors and contributing to the release of their metabolites into the environment.

Identification of novel F2-isoprostane metabolites by specific UDP-glucuronosyltransferases

UDP-glucuronosyltransferases (UGTs) catalyze the conjugation of glucuronic acid with endogenous and exogenous lipophilic small molecules to facilitate their inactivation and excretion from the body. This represents approximately 35 % of all phase II metabolic transformations. Fatty acids and their oxidized eicosanoid derivatives can be metabolized by UGTs. F2-isoprostanes (F2-IsoPs) are eicosanoids formed from the free radical oxidation of arachidonic acid. These molecules are potent vasoconstrictors and are widely used as biomarkers of endogenous oxidative damage. An increasing body of evidence demonstrates the efficacy of measuring the β-oxidation metabolites of F2-IsoPs rather than the unmetabolized F2-IsoPs to quantify oxidative damage in certain settings. Yet, the metabolism of F2-IsoPs is incompletely understood. This study sought to identify and characterize novel phase II metabolites of 15-F2t-IsoP and 5-epi-5-F2t-IsoP, two abundantly produced F2-IsoPs, in human liver microsomes (HLM). Utilizing liquid chromatography-mass spectrometry, we demonstrated that glucuronide conjugates are the major metabolites of these F2-IsoPs in HLM. Further, we showed that these molecules are metabolized by specific UGT isoforms. 15-F2t-IsoP is metabolized by UGT1A3, 1A9, and 2B7, while 5-epi-5-F2t-IsoP is metabolized by UGT1A7, 1A9, and 2B7. We identified, for the first time, the formation of intact glucuronide F2-IsoPs in human urine and showed that F2-IsoP glucuronidation is reduced in people supplemented with eicosapentaenoic and docosahexaenoic acids for 12 weeks. These studies demonstrate that endogenous F2-IsoP levels can be modified by factors other than redox mechanisms.

Simultaneous Detection of Aldehyde Metabolites by Light-Assisted Ambient Ionization Mass Spectrometry.

In the clinic, small-molecule metabolites (SMMs) in blood are highly convincing indicators for disease diagnosis, such as cancer. However, challenges still exist for detection of SMMs due to their low concentration and complicated components in blood. In this work, we report the design of a novel "selenium signature" nanoprobe (Se nanoprobe) for efficient identification of multiple aldehyde metabolites in blood. This Se nanoprobe consists of magnetic nanoparticles that can enrich aldehyde metabolites from a complex environment, functionalized with photosensitive "selenium signature" hydrazide molecules that can react with aldehyde metabolites. Upon irradiation with UV, the aldehyde derivatives can be released from the Se nanoprobe and further sprayed by mass spectrometry through ambient ionization (AIMS). By quantifying the selenium isotope distribution (MS/MS) from the derivatization product, accurate detection of several aldehyde metabolites, including valeraldehyde (Val), heptaldehyde (Hep), 2-furaldehyde (2-Fur), 10-undecenal aldehyde (10-Und), and benzaldehyde (Ben), is realized. This strategy reveals a new solution for quick and accurate cancer diagnosis in the clinic.

Antioxidant and anticholinesterase properties of Echinometra mathaei and Ophiocoma erinaceus venoms from the Persian Gulf.

Introduction: The Persian Gulf is home to a diverse range of marine life, including various species of fish, crustaceans, mollusks, and echinoderms. This study investigates the potential therapeutic properties of venoms from echinoderms in the Persian Gulf, specifically their ability to inhibit cholinesterases (Acetylcholinesterase and butyrylcholinesterase) and act as antioxidants. Methods: Four venoms from two echinoderm species, including the spine, gonad, and coelomic fluids of sea urchins, as well as brittle star venoms, were analyzed using various methods, including LD50 determination, protein analysis, antioxidant assays, GC-MS for secondary metabolite identification, and molecular docking simulations. Results and discussion: The study's results revealed the LD50 of the samples as follows: 2.231 ± 0.09, 1.03 ± 0.05, 1.12 ± 0.13, and 6.04 ± 0.13mg/mL, respectively. Additionally, the protein levels were 44.037 ± 0.002, 74.223 ± 0.025, 469.97 ± 0.02, and 104.407 ± 0.025μg/mL, respectively. SDS-PAGE and total protein studies indicated that at least part of the venom was proteinaceous. Furthermore, the study found that the brittle star samples exhibited significantly higher antioxidant activity compared to other samples, including the standard ascorbic acid, at all tested concentrations. GC-MS analysis identified 12, 23, 21, and 25 compounds in the samples, respectively. These compounds had distinct chemical and bioactive structures, including alkaloids, terpenes, and steroids. Conclusion: These venoms displayed strong cholinesterase inhibitory and antioxidant activities, likely attributed to their protein content and the presence of alkaloids, terpenes, and steroids. Notably, the alkaloid compound C 7 was identified as a promising candidate for further research in Alzheimer's disease therapy. In conclusion, echinoderms in the Persian Gulf may hold significant potential for discovering novel therapeutic agents.

Genome-wide identification and expression analysis of the ADH gene family under diverse stresses in tobacco (Nicotiana tabacum L.)

BackgroundAlcohol dehydrogenases (ADHs) are the crucial enzymes that can convert ethanol into acetaldehyde. In tobacco, members of ADH gene family are involved in various stresses tolerance reactions, lipid metabolism and pathways related to plant development. It will be of great application significance to analyze the ADH gene family and expression profile under various stresses in tobacco.ResultsA total of 53 ADH genes were identified in tobacco (Nicotiana tabacum L.) genome and were grouped into 6 subfamilies based on phylogenetic analysis. Gene structure (exon/intron) and protein motifs were highly conserved among the NtADH genes, especially the members within the same subfamily. A total of 5 gene pairs of tandem duplication, and 3 gene pairs of segmental duplication were identified based on the analysis of gene duplication events. Cis-regulatory elements of the NtADH promoters participated in cell development, plant hormones, environmental stress, and light responsiveness. The analysis of expression profile showed that NtADH genes were widely expressed in topping stress and leaf senescence. However, the expression patterns of different members appeared to be diverse. The qRT-PCR analysis of 13 NtADH genes displayed their differential expression pattern in response to the bacterial pathogen Ralstonia solanacearum L. infection. Metabolomics analysis revealed that NtADH genes were primarily associated with carbohydrate metabolism, and moreover, four NtADH genes (NtADH20/24/48/51) were notably involved in the pathway of alpha-linolenic acid metabolism which related to the up-regulation of 9-hydroxy-12-oxo-10(E), 15(Z)-octadecadienoic acid and 9-hydroxy-12-oxo-15(Z)-octadecenoic acid.ConclusionThe genome-wide identification, evolutionary analysis, expression profiling, and exploration of related metabolites and metabolic pathways associated with NtADH genes have yielded valuable insights into the roles of these genes in response to various stresses. Our results could provide a basis for functional analysis of NtADH gene family under stressful conditions.