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In the present study, the main objective is to develop an analytical method for ultra-trace level measurement of 2,6-diamino-5-nitropyrimidin-4(3H)-one (DMNP) in valganciclovir hydrochloride (VAL) using liquid chromatography-quadrupole time-of-flight-tandem mass spectroscopy (LC-QTOF-MS/MS). In the early stages of guanine synthesis, DMNP is formed, and guanine is known to be the key starting material for the synthesis of VAL. Taking into consideration DMNP potential genotoxicity, this analytical method has been developed. This method is time saving and suitable for confirming the masses of parent and fragment ions by MS and MS/MS further fragmentation. An isocratic program and Acquity UPLC HSS cyano column (100 × 2.1 mm × 1.8 µm) were used to achieve optimal separation between VAL and the DMNP impurity. A 0.1% ammonia solution in Milli-Q water was used as mobile phase A, and methanol was used as mobile phase B in the ratio 90:10 v/v in isocratic mode. In accordance with the International Conference on Harmonization's requirements, the developed method was validated. The detection and quantification levels were found to be 0.028 and 0.083 ppm respectively. The DMNP impurity is linear from 0.083 to 1.245 ppm levels with correlation coefficient (R2 ) of 0.9960. The recoveries were found to be 97.0-107.9%.
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Dano ao DNA , Espectrometria de Massas em Tandem , Valganciclovir , Cromatografia Líquida , Guanina , Cromatografia Líquida de Alta PressãoRESUMO
INTRODUCTION: Winegrape varieties Kotsifali, Limnio, and Vradiano OBJECTIVE: The aim of this study was to develop a liquid chromatographic quadrupole time-of-flight tandem mass spectrometric (LC-QTOF-MS/MS) method for the investigation of the anthocyanin and proanthocyanidin content of Greek grape varieties employing target and suspect screening strategies. METHODOLOGY: A novel LC-QTOF-MS/MS method was developed and validated to assess the anthocyanin content of Kotsifali, Limnio, and Vradiano grape varieties. Sixteen grape samples were collected from the main growing areas of each variety in Greece. The influence of the grape variety on the anthocyanin and proanthocyanidin composition of three Greek winegrapes was investigated using chemometrics. RESULTS: Excellent linearity (R2 > 0.99) was achieved for all the target analytes, and recoveries ranged between 90.1% and 119.1%. The limits of quantification (LOQs) and limits of detection (LODs) were calculated over the range of 0.020-0.40 mg/g and 0.010-0.13 mg/g, respectively. The RSD% was lower than 9.1% and 7.3% for intra-day and inter-day studies, respectively, indicating satisfactory trueness and precision. Target and suspect screening resulted in the identification of 5 and 26 anthocyanins, respectively. CONCLUSIONS: Kotsifali variety exhibited a higher concentration of anthocyanins compared with Vradiano and Limnio. Higher levels of mean degree of polymerization (mDp) and different percentage levels of prodelphinidins (%P) were established among the varieties.
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The pomegranate processing industry generates worldwide enormous amounts of by-products, such as pomegranate peels (PPs), which constitute a rich source of phenolic compounds. In this view, PPs could be exploited as a sustainable source of ellagic acid, which is a compound that possesses various biological actions. The present study aimed at the liberation of ellagic acid from its bound forms via ultrasound-assisted alkaline hydrolysis, which was optimized using response surface methodology. The effects of duration of sonication, solvent:solid ratio, and NaOH concentration on total phenol content (TPC), antioxidant activity, and punicalagin and ellagic acid content were investigated. Using the optimum hydrolysis conditions (i.e., 32 min, 1:48 v/w, 1.5 mol/L NaOH), the experimental responses were found to be TCP: 4230 ± 190 mg GAE/100 g dry PPs; AABTS: 32,398 ± 1817 µmol Trolox/100 g dry PPs; ACUPRAC: 29,816 ± 1955 µmol Trolox/100 g dry PPs; 59 ± 3 mg punicalagin/100 g dry PPs; and 1457 ± 71 mg ellagic acid/100 g dry PPs. LC-QTOF-MS and GC-MS analysis of the obtained PP extract revealed the presence of various phenolic compounds (e.g., ellagic acid), organic acids (e.g., citric acid), sugars (e.g., fructose) and amino acids (e.g., glycine). The proposed methodology could be of use for food, pharmaceutical, and cosmetics applications, thus reinforcing local economies.
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Antioxidantes , Ácido Elágico , Punica granatum , Ácido Elágico/química , Punica granatum/química , Hidrólise , Antioxidantes/química , Fenóis/química , Fenóis/análise , Extratos Vegetais/química , Taninos Hidrolisáveis/química , Frutas/químicaRESUMO
BACKGROUND: Mangifera indica L. (mango), a medicinal plant rich in biologically active compounds, has potential to be used in disease-preventing and health-promoting products. The present investigation reveals and uncovers bioactive metabolites with remarkable therapeutic efficiency from mango (family: Anacardiaceae) seeds. RESULTS: Biological activity was determined by antimicrobial, antioxidant and anticancer assays, and metabolite profiling was performed on gas chromatography coupled to quadrupole time-of-flight mass spectrometry (GC-QTOF-MS) and liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) platforms. Validation of active metabolites was carried out by in silico molecular docking (Molinspiration Cheminformatics Server and PASS). Extracted and identified metabolites were screened; 54 compounds associated with various groups were selected for the in silico interaction study. CONCLUSIONS: Molecular docking revealed lead molecules with a potential binding energy score, efficacy and stable modulation with a selected protein domain. Investigation, directed by in vitro and in silico analysis, confirms mango seeds as an excellent source of potential metabolites as a therapeutic agent. © 2024 Society of Chemical Industry.
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Descoberta de Drogas , Mangifera , Metabolômica , Simulação de Acoplamento Molecular , Extratos Vegetais , Sementes , Mangifera/química , Sementes/química , Sementes/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/metabolismo , Humanos , Cromatografia Gasosa-Espectrometria de Massas , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/metabolismoRESUMO
This is the first study that quantified quercetin (QUE) and its 16 metabolites in the breast milk of QUE-fed maternal mice, the plasma and urine of that, and neonatal mice. Interestingly, the QUE aglycone concentration in the milk was much higher than in the plasma of maternal mice, suggesting that QUE may exert biological activity in neonates.
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Leite Humano , Quercetina , Animais , Camundongos , Animais Recém-NascidosRESUMO
Yangzheng Mixture is a traditional Chinese medicine used in clinical practice as an adjuvant therapy for tumors. However, little is known about its active components in tumor treatment. The purpose of this study was to explore the potential anti-tumor components of Yangzheng Mixture to better promote its clinical application. Using LC-MS/MS, 43 components were detected in concentrated Yangzheng Mixture. Six components, comprising astragaloside, calycosin, formononetin, isoquercitrin, ononin, and calycosin-7-O-ß-D-glucoside, were identified in rat plasma. The cancer cell absorption assay showed that the intracellular concentration of four components, calycosin, calycosin-7-O-ß-D-glucoside, formononetin, and ononin, increased with extended incubation time and demonstrated potential anti-tumor effects. The MTT assay results confirmed that Yangzheng Mixture inhibited different tumor cells proliferation. Additionally, the colony formation assay, flow cytometry analysis and wound healing displayed that Yangzheng Mixture and a combination of four components could inhibit colony formation, arrest the cell cycle and impair cell migration of tumor cells, including HCT-116, MHCC-97L, MCF-7 and NCI-H1299. In summary, our study highlighted the plausible application of Yangzheng Mixture as a potential adjuvant treatment for tumors. Furthermore, it identified effective anti-tumor components and provided evidences for the further clinical application of Yangzheng Mixture.
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The lichen Cetraria islandica (L.) Ach. has been used in traditional and modern medicines for its many biological properties such as immunological, immunomodulating, antioxidant, antimicrobial, and anti-inflammatory activities. This species is gaining popularity in the market, with interest from many industries for selling as medicines, dietary supplements, and daily herbal drinks. This study profiled the morpho-anatomical features by light, fluorescence, and scanning electron microscopy; conducted an elemental analysis using energy-dispersive X-ray spectroscopy; and phytochemical analysis was performed using high-resolution mass spectrometry combined with a liquid chromatography system (LC-DAD-QToF) of C. islandica. In total, 37 compounds were identified and characterized based on comparisons with the literature data, retention times, and their mass fragmentation mechanism/s. The identified compounds were classified under five different classes, i.e., depsidones, depsides, dibenzofurans, aliphatic acids, and others that contain simple organic acids in majority. Two major compounds (fumaroprotocetraric acid and cetraric acid) were identified in the aqueous ethanolic and ethanolic extracts of C. islandica lichen. This detailed morpho-anatomical, EDS spectroscopy, and the developed LC-DAD-QToF approach for C. islandica will be important for correct species identification and can serve as a useful tool for taxonomical validation and chemical characterization. Additionally, chemical study of the extract of C. islandica led to isolation and structural elucidation of nine compounds, namely cetraric acid (1), 9'-(O-methyl)protocetraric acid (2), usnic acid (3), ergosterol peroxide (4), oleic acid (5), palmitic acid (6), stearic acid (7), sucrose (8), and arabinitol (9).
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Líquens , Parmeliaceae , Parmeliaceae/química , Raios X , Líquens/química , Antioxidantes/farmacologia , Suplementos Nutricionais , Cromatografia Líquida de Alta Pressão , Extratos VegetaisRESUMO
Lime peels are food waste from lime product manufacturing. We previously developed and optimized a green extraction method for hesperidin-limonin-rich lime peel extract. This study aimed to identify the metabolomics profile of phytochemicals and the anti-cancer effects of ethanolic extract of lime (Citrus aurantifolia) peel against liver cancer cells PLC/PRF/5. The extract's metabolomics profile was analyzed by using LC-qTOF/MS and GC-HRMS. The anti-cancer effects were studied by using MTT assay, Annexin-PI assay, and Transwell-invasion assay. Results show that the average IC50(s) of hesperidin, limonin, and the extract on cancer cells' viability were 165.615, 188.073, and 503.004 µg/mL, respectively. At the IC50 levels, the extract induced more apoptosis than those of pure compounds when incubating for 24 and 48 h (p < 0.0001). A combination of limonin and hesperidin showed a synergistic effect on apoptosis induction (p < 0.001), but the effect of the combination was still less than that of the extract at 48 h. Furthermore, the extract significantly inhibited cancer cell invasion better than limonin but equal to hesperidin. At the IC50 level, the extract contains many folds lower amounts of hesperidin and limonin than the IC50 doses of the pure compounds. Besides limonin and hesperidin, there were another 60 and 22 compounds detected from the LCMS and GCMS analyses, respectively. Taken altogether, the superior effect of the ethanolic extract against liver cancer cells compared to pure compound likely results from the combinatorial effects of limonin, hesperidin, and other phytochemical components in the extract.
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Carcinoma Hepatocelular , Citrus , Hesperidina , Limoninas , Neoplasias Hepáticas , Eliminação de Resíduos , Humanos , Hesperidina/química , Carcinoma Hepatocelular/tratamento farmacológico , Limoninas/farmacologia , Limoninas/análise , Alimentos , Neoplasias Hepáticas/tratamento farmacológico , Citrus/química , Extratos Vegetais/químicaRESUMO
There have been many attempts in pharmaceutical industries and academia to improve the pharmacokinetic characteristics of anti-tumor small-molecule drugs by conjugating them with large molecules, such as monoclonal antibodies, called ADCs. In this context, albumin, one of the most abundant proteins in the blood, has also been proposed as a large molecule to be conjugated with anti-cancer small-molecule drugs. The half-life of albumin is 3 weeks in humans, and its distribution to tumors is higher than in normal tissues. However, few studies have been conducted for the in vivo prepared albumin-drug conjugates, possibly due to the lack of robust bioanalytical methods, which are critical for evaluating the ADME/PK properties of in vivo prepared albumin-drug conjugates. In this study, we developed a bioanalytical method of the albumin-conjugated MAC glucuronide phenol linked SN-38 ((2S,3S,4S,5R,6S)-6-(4-(((((((S)-4,11-diethyl-4-hydroxy-3,14-dioxo-3,4,12,14-tetrahydro-1H-pyrano [3',4':6,7] indolizino [1,2-b] quinolin-9-yl)oxy)methyl)(2 (methylsulfonyl)ethyl)carbamoyl)oxy)methyl)-2-(2-(3-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)-N-methylpropanamido)acetamido)phenoxy)-3,4,5-trihydroxytetra-hydro-2H-pyran-2-carboxylic acid) as a proof-of-concept. This method is based on immunoprecipitation using magnetic beads and the quantification of albumin-conjugated drug concentration using LC-qTOF/MS in mouse plasma. Finally, the developed method was applied to the in vivo intravenous (IV) mouse pharmacokinetic study of MAC glucuronide phenol-linked SN-38.
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Albuminas , Imunoprecipitação , Irinotecano , Espectrometria de Massa com Cromatografia Líquida , Animais , Humanos , Camundongos , Albuminas/química , Albuminas/farmacocinética , Glucuronidase/metabolismo , Glucuronídeos/química , Glucuronídeos/metabolismo , Imunoprecipitação/métodos , Irinotecano/sangue , Irinotecano/química , Irinotecano/metabolismo , Irinotecano/farmacocinética , Espectrometria de Massa com Cromatografia Líquida/métodos , Magnetismo , Fenol/químicaRESUMO
BACKGROUND: Nanoencapsulation has opened promising fields of innovation for pesticides. Conventional pesticides can cause side effects on plant metabolism. To date, the effect of nanoencapsulated pesticides on plant phenolic contents has not been reported. RESULTS: In this study, a comparative evaluation of the phenolic contents and metabolic profiles of strawberries was performed for plants grown under controlled field conditions and treated with two separate active ingredients, azoxystrobin and bifenthrin, loaded into two different types of nanocarriers (Allosperse® polymeric nanoparticles and SiO2 nanoparticles). There were small but significant decreases of the total phenolic content (9%) and pelargonidin 3-glucoside content (6%) in strawberries treated with the nanopesticides. An increase of 31% to 125% was observed in the levels of gallic acid, quercetin, and kaempferol in the strawberries treated with the nanoencapsulated pesticides compared with the conventional treatments. The effects of the nanocarriers on the metabolite and phenolic profiles was identified by principal component analysis. CONCLUSION: Overall, even though the effects of nanopesticides on the phenological parameters of strawberry plants were not obvious, there were significant changes to the plants at a molecular level. In particular, nanocarriers had some subtle effects on plant health and fruit quality through variations in total and individual phenolics in the fruits. Further research will be needed to assess the impact of diverse nanopesticides on other groups of plant metabolites. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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The purpose of this study is to investigate the difference of in vitro-in vivo correlation of α-amanitin from clearance perspectives as well as to explore the possibility of extra-hepatic metabolism of α-amanitin. First, a liquid chromatography-quadrupole-time-of-flight-mass spectrometric (LC-qTOF-MS) method for α-amanitin in rat plasma was developed and applied to evaluate the in vitro liver microsomal metabolic stability using rat and human liver microsomes and the pharmacokinetics of α-amanitin in rat. The predicted hepatic clearance of α-amanitin in rat liver microsomes was quite low (5.05 mL/min/kg), whereas its in vivo clearance in rat (14.0 mL/min/kg) was close to the borderline between low and moderate clearance. To find out the difference between in vitro and in vivo metabolism, in vitro and in vivo metabolite identification was also conducted. No significant metabolites were identified from the in vivo rat plasma and the major circulating entity in rat plasma was α-amanitin itself. No reactive metabolites such as GSH-adducts were detected either. A glucuronide metabolite was newly identified from the in vitro liver microsomes samples with a trace level. A semi-mass balance study was also conducted to understand the in vivo elimination pathway of α-amanitin and it showed that most α-amanitin was mainly eliminated in urine as intact which implies some unknown transporters in kidney might play a role in the elimination of α-amanitin in rat in vivo. Further studies with transporters in the kidney would be warranted to figure out the in vivo clearance mechanism of α-amanitin.
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Alfa-Amanitina , Microssomos Hepáticos , Ratos , Humanos , Animais , Alfa-Amanitina/metabolismo , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Microssomos Hepáticos/metabolismo , Plasma , Cromatografia Líquida de Alta Pressão/métodosRESUMO
Daporinad (FK866) is one of the highly specific inhibitors of nicotinamide phosphoribosyl transferase (NAMPT) and known to have its unique mechanism of action that induces the tumor cell apoptosis. In this study, a simple and sensitive liquid chromatography-quadrupole-time-of-flight-mass spectrometric (LC-qTOF-MS) assay has been developed for the evaluation of drug metabolism and pharmacokinetics (DMPK) properties of Daporinad in mice. A simple protein precipitation method using acetonitrile (ACN) was used for the sample preparation and the pre-treated samples were separated by a C18 column. The calibration curve was evaluated in the range of 1.02~2220 ng/mL and the quadratic regression (weighted 1/concentration2) was used for the best fit of the curve with a correlation coefficient ≥ 0.99. The qualification run met the acceptance criteria of ±25% accuracy and precision values for QC samples. The dilution integrity was verified for 5, 10 and 30-fold dilution and the accuracy and precision of the dilution QC samples were also satisfactory within ±25% of the nominal values. The stability results indicated that Daporinad was stable for the following conditions: short-term (4 h), long-term (2 weeks), freeze/thaw (three cycles). This qualified method was successfully applied to intravenous (IV) pharmacokinetic (PK) studies of Daporinad in mice at doses of 5, 10 and 30 mg/kg. As a result, it showed a linear PK tendency in the dose range from 5 to 10 mg/kg, but a non-linear PK tendency in the dose of 30 mg/kg. In addition, in vitro and in vivo metabolite identification (Met ID) studies were conducted to understand the PK properties of Daporinad and the results showed that a total of 25 metabolites were identified as ten different types of metabolism in our experimental conditions. In conclusion, the LC-qTOF-MS assay was successfully developed for the quantification of Daporinad in mouse plasma as well as for its in vitro and in vivo metabolite identification.
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Plasma , Espectrometria de Massas em Tandem , Animais , Calibragem , Cromatografia Líquida/métodos , Camundongos , Espectrometria de Massas em Tandem/métodosRESUMO
Daylily is a valuable plant resource with various health benefits. Its main bioactive components are phenolic compounds. In this work, four extraction methods, ultrasonic-assisted water extraction (UW), ultrasonic-assisted ethanol extraction (UE), enzymatic-assisted water extraction (EW), and enzymatic-assisted ethanol extraction (EE), were applied to extract phenolic compounds from daylily. Among the four extracts, the UE extract exhibited the highest total phenolic content (130.05 mg/100 g DW) and the best antioxidant activity. For the UE extract, the DPPH value was 7.75 mg Trolox/g DW, the FRAP value was 14.54 mg Trolox/g DW, and the ABTS value was 15.37 mg Trolox/g DW. A total of 26 phenolic compounds were identified from the four extracts, and the UE extract exhibited a higher abundance range of phenolic compounds than the other three extracts. After multivariate statistical analysis, six differential compounds were selected and quantified, and the UE extract exhibited the highest contents of all six differential compounds. The results provided theoretical support for the extraction of phenolic compounds from daylily and the application of daylily as a functional food.
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Hemerocallis , Antioxidantes/química , Etanol , Hemerocallis/química , Fenóis/química , Extratos Vegetais/química , ÁguaRESUMO
In recent years, recorded cases related to forensic botany and, in particular, of plant poisoning have become rare. We report on the medicolegal characteristics of an undetermined sudden death (USD) of a woman in which scene there were remnants of a vegetal peeling. After the autopsy, macroscopic findings reported multiorgan failure and requested the investigation of the cause of death. Postmortem blood was firstly investigated on cyanide toxicity presumptively coming from a yucca-like root; however, found cyanide levels were under normality. Because of the lack of morphological features of the encountered plant remains, a genetic nrDNA ITS2 sequence investigation was followed. The resulting DNA sequence could identify the evidence as the water dropwort (Oenanthe spp.) which contains oenanthotoxin, a potent toxin that may be fatal, similar to the more commonly found in hemlock Conium or cowbane Cicuta species. A liquid chromatography-tandem high resolution mass spectrometry (LC-QTOF MS) was later applied to analyse the vegetal extract and stomach content and successfully confirmed the toxin existence. Medicolegal and analytical findings at the forensic laboratory were described, where both biological and chemical techniques could successfully conjugate, as an interdisciplinary research, and explain premortem symptoms and postmortem findings. Present data can be helpful in future investigation on poisoning cases by conjugated polyacetylenes . The present work tries to emphasize the often undervalued plant evidence in legal medicine diagnosis in the context of an unexplained death.
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Morte Súbita/etiologia , Enedi-Inos/intoxicação , Álcoois Graxos/intoxicação , Genética Forense , Toxicologia Forense , Oenanthe/intoxicação , Intoxicação por Plantas , Idoso de 80 Anos ou mais , Cromatografia Líquida , Código de Barras de DNA Taxonômico , Feminino , Humanos , Espectrometria de Massas em TandemRESUMO
We aimed to develop a standardized methodology to determine the metabolic profile of organic extracts from Malvaviscus arboreus Cav. (Malvaceae), a Mexican plant used in traditional medicine for the treatment of hypertension and other illnesses. Also, we determined the vasorelaxant activity of these extracts by ex vivo rat thoracic aorta assay. Organic extracts of stems and leaves were prepared by a comprehensive maceration process. The vasorelaxant activity was determined by measuring the relaxant capability of the extract to decrease a contraction induced by noradrenaline (0.1â µM). The hexane extract induced a significant vasorelaxant effect in a concentration- and endothelium-dependent manner. Secondary metabolites, such as polyunsaturated fatty acids, terpenes and one flavonoid, were annotated by liquid chromatography/quadrupole time-of-flight mass spectrometry (LC/QTOF-MS) in positive ion mode. This exploratory study allowed us to identify bioactive secondary metabolites from Malvaviscus arboreus, as well as identify potentially-new vasorelaxant molecules and scaffolds for drug discovery.
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Aorta Torácica/química , Malvaceae/química , Extratos Vegetais/metabolismo , Vasodilatadores/metabolismo , Animais , Aorta Torácica/metabolismo , Cromatografia Líquida , Masculino , Malvaceae/metabolismo , Espectrometria de Massas , Estrutura Molecular , Extratos Vegetais/análise , Ratos , Ratos Wistar , Vasodilatadores/análiseRESUMO
INTRODUCTION: Lagenaria siceraria, is a popular food plant among Indians, contains a large number of phenolic compounds with several medicinal benefits, mentioned in Indian System of Medicine (ISM). OBJECTIVES: To investigate the carbonic anhydrase inhibitory potential and inhibitory mechanism of the most potent fraction of L. siceraria fruits. MATERIALS AND METHODS: The extract and fraction of dried fruit of L. siceraria screened for their in vitro carbonic anhydrase II (bCA II) inhibitory activity. The active fraction was purified by using flash chromatography. The bioactive compounds were identified and quantified through liquid chromatography quadrupole time-of-flight tandem mass spectrometry (LC-QTOF-MS/MS) and reverse-phase high-performance liquid chromatography (RP-HPLC). Finally, the underlying carbonic anhydrase inhibitory mechanism of the compounds was explained by enzyme kinetics and molecular docking study. RESULTS: The LC-QTOF-MS based identification of the most active fraction revealed the presence of phenolic compounds. The results of the enzyme inhibition assay revealed that coniferyl alcohol, ferulic acid and p-Coumaric acid inhibited bCA II activity [half maximal inhibitory concentration (IC50 ) value range of 80 to 250 µM) in a dose dependent manner. The kinetics study of enzyme inhibition revealed that p-Coumaric acid binds to the enzyme competitively whereas the non-competitive type of inhibition was observed for ferulic acid and coniferyl alcohol. The molecular docking study explored the interaction mechanism of phenolic compounds at the active site of bCA II. CONCLUSION: The present research led us to conclude that, the phenolic compounds from L. siceraria serve as major contributors for carbonic anhydrase inhibition, which could play a useful role in the management of oedema, hypertension, obesity and related metabolic disorders.
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Anidrases Carbônicas , Anidrase Carbônica II , Cromatografia Líquida , Simulação de Acoplamento Molecular , Espectrometria de Massas em TandemRESUMO
INTRODUCTION: Pyranosides as one kind of natural glycosides contain a pyran ring linked to an aglycone in the structure. They occur widely in plants and possess diverse biological activities. The discovery of new pyranosides not only contributes to research on natural products but also may promote pharmaceutical development. OBJECTIVES: A non-targeted liquid chromatography-quadrupole time-of-flight mass spectrometry method coupled with an all ion fragmentation-exact neutral loss (AIF-ENL) strategy was developed for the screening of pyranosides in plants. METHODS: Pyranosides in various types were collected as a model. The AIF-ENL strategy comprised three steps: AIF spectrum acquisition and generation, ENL-based searching and identification, and confirmation of structural type using target second-stage mass spectrometry (MS/MS). The strategy was systematically evaluated based on the matrix effects, fragmentation stability, scan rate and screening efficiency and finally applied to Rhodiola crenulata (Hook. f. et Thoms) H. Ohba. RESULTS: The method was proved to be an efficient tool for the screening of pyranosides. When it was applied to R. crenulata, a total of 24 pyranoside candidates were detected. Among them, six were tentatively identified on the basis of the agreement of their elemental composition with the reported. The other 18 were detected in R. crenulata for the first time. CONCLUSION: The method offers a new platform for discovering pyranosides. In addition, the developed non-targeted strategy can also be used for other natural products, such as flavonoids and coumarins, as long as there is a common fragmentation behaviour in their MS/MS to generate characteristic neutral losses or fragments.
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Rhodiola , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Flavonoides/análise , Glicosídeos , Espectrometria de Massas em TandemRESUMO
Ethanol extracts of two types of pepper (sweet and hot) were separated into fractions with increasing lipophilicity. After drying the extracts and fractions, their chemical composition, anti-radical activity in the DPPH radical system, and cytotoxic activity against PC-3 and HTC-116 cells were determined. A detailed qualitative analysis of the fractions was performed with the LC-QTOF-MS method. It was found that the chemical composition of pepper fractions did not always reflect their biological activity. The highest antiradical activity was detected in the fraction eluted with 40% methanol from sweet pepper. The highest total content of phenolic compounds was found in an analogous fraction from hot pepper, and this fraction showed the strongest cytotoxic effect on the PC-3 tumour line. The LC-MS analysis identified 53 compounds, six of which were present only in sweet pepper and four only in hot pepper. The unique chemical composition of the extracts was found to modulate their biological activity, which can only be verified experimentally.
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Capsicum/química , Extratos Vegetais/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Fenóis/química , Piper nigrum/química , Verduras/químicaRESUMO
Marine aquaculture development is recently impeded by parasitic leech Zeylanicobdella arugamensis (Hirudinea, Piscicolidae) in Sabah, Malaysia. The parasitic leech infests a variety of cultured fishes in aquaculture facilities. In this study, we evaluated the antiparasitic activity of the chromatographic fractions of the medicinal plant Nephrolepis biserrata methanol extract against Z. arugamensis and highlighted the potential metabolites responsible for the antiparasitic properties through liquid chromatography (LC)-quadrupole time-of-flight (QTOF)-mass spectrometry (MS) analysis. Out of seven fractions obtained through flash column chromatography techniques, three fractions demonstrated antiparasitic properties. Significant parasitic mortality was indicated by fraction 3 at a concentration of 2.50 mg/mL, all the leeches were killed in a time limit of 1.92 ± 0.59 min. followed by fraction 4 (14 mg/mL) in 34.57 ± 3.39 and fraction 5 (15.3 mg/mL) in 36.82 ± 4.53 min. LC-QTOF-MS analysis indicated the presence of secondary metabolites including phytosphingosine (6), pyrethrosin (1), haplophytine (9), ivalin (2), warburganal (3), isodomedin (4) and pheophorbide a (16), representing sphingoid, alkaloid, terpenoid, phenolic and flavonoid groups. Thus, our study indicated that the chromatographic fractions of N. biserrata demonstrated significant antiparasitic activity against the marine parasitic leeches due to the presence of potent antiparasitic bioactive compounds.
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Antiparasitários/química , Antiparasitários/farmacologia , Cromatografia Líquida , Espectrometria de Massas , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Traqueófitas/químicaRESUMO
BACKGROUND: Okara is a major agri-industrial by-product of the tofu and soymilk industries. Employing food-wastes as substrates for the green production of natural functional compounds is a recent trend that addresses the dual concepts of sustainable production and a zero-waste ecosystem. RESULTS: Extracts of unfermented okara and okara fermented with Rhizopus oligosporus were obtained using ethanol as extraction solvent, coupled with ultrasound sonication for enhanced extraction. Fermented extracts yielded significantly better results for total phenolic content (TPC) and total flavonoid content (TFC) than unfermented extracts. A qualitative liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) analysis revealed a shift from glucoside forms to respective aglycone forms of the detected isoflavones, post-fermentation. Since the aglycone forms have been associated with numerous health benefits, a quantitative high-performance liquid chromatography (HPLC) analysis was performed. Fermented okara extracts had daidzein and genistein concentrations of 11.782 ± 0.325 µg mL-1 and 10.125 ± 1.028 µg mL-1 , as opposed to that of 6.7 ± 2.42 µg mL-1 and 4.55 ± 0.316 µg mL-1 in raw okara extracts, respectively. Lastly, the detected isoflavones were mapped to their metabolic pathways, to understand the biochemical reactions triggered during the fermentation process. CONCLUSION: Fermented okara may be implemented as a sustainable solution for production of natural bioactive isoflavonoids genistein and daidzein. © 2021 Society of Chemical Industry.