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1.
Pharmaceuticals (Basel) ; 17(8)2024 Aug 22.
Article in English | MEDLINE | ID: mdl-39204205

ABSTRACT

Pseudotrimezia juncifolia (Klatt) Lovo & A. Gil (Iridaceae) is a popularly known species with primarily ornamental economic interest. It has traditional uses as purgative, in conditions related to the menstrual cycle, for blood purification, as wound healing, and as anti-inflammatory. The anti-inflammatory and antinociceptive activities of the decoction from its aerial stems, corms, and stamens are described here with dereplication studies on LC-MS/MS supported by the GNPS platform, where phenolic compounds were annotated and correlated with its biological activity. The decoction was evaluated in chemical (formalin and capsaicin) and thermal (hot plate) induced nociception or carrageenan-induced inflammation in mice. Decoction (at 10, 30, or 100 mg/kg doses) significantly reduced formalin- or capsaicin-induced nociception. All doses also demonstrated an antinociceptive effect in the hot plate model increasing the time the animal spent in responding to thermal signal. Naloxone partially reversed the antinociceptive effect. An anti-inflammatory effect was observed since a reduction in cell migration, protein extravasation interleukin-1, and tumor necrosis factor production induced by carrageenan in the subcutaneous air pouch was quantified. Metabolomic analyses showed a predominance of phenolic substances, mainly flavonoids and chlorogenic acids. The literature showed that these two groups have significant anti-inflammatory and analgesic activity, and chemical data corroborate the pharmacological results observed.

2.
Chem Biodivers ; 21(7): e202400670, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38747034

ABSTRACT

Cancer remains a significant global health concern, with mortality rates steadily rising and prompting an urgent search for effective treatments. This study focuses on the medicinal properties of plants from the Phyllanthus genus, specifically Phyllanthus amarus and Phyllanthus niruri, which have shown promise in traditional medicine. Through bioguided fractionation using preparative high-performance liquid chromatography (HPLC), bioactive compounds were isolated and identified using ultra-performance liquid chromatography coupled to time-of-flight mass spectrometry (UHPLC-QTOF-MSE) and nuclear magnetic resonance (NMR) spectroscopy. Chemometric analyses such as principal component analysis (PCA) aided in understanding metabolite distribution. Biological assays demonstrated cytotoxic activities of specific fractions against cancer cell lines, notably the PhyN 4n fraction from P. niruri, which induced S-phase cell cycle arrest and apoptosis in HL60 cells. These findings underscore the anticancer potential of Phyllanthus species and lay the groundwork for future drug development efforts. The study's integration of advanced analytical techniques, chemometrics, and biological assays provides valuable insights for harnessing natural products in the fight against cancer.


Subject(s)
Antineoplastic Agents, Phytogenic , Apoptosis , Drug Screening Assays, Antitumor , Metabolomics , Phyllanthus , Phyllanthus/chemistry , Humans , Antineoplastic Agents, Phytogenic/pharmacology , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Apoptosis/drug effects , Chromatography, High Pressure Liquid , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plant Extracts/isolation & purification , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug
3.
Fitoterapia ; 175: 105972, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38657781

ABSTRACT

Molecular dereplication and drug-like discovery are important tools for exploring the chemical profile of metabolites in a complex mixture. In order to establish a workflow for discovering novel acetylcholinesterase (AChE) ligands, we performed the chemical study of Myrsine guianensis (Aubl.) Kuntze (Primulaceae). To carry out the bioprospection, nine extracts were obtained from different parts of the plant. Through the dereplication approaches, seventeen metabolites were annotated. In order to confirm the putative inferences, a HPLC preparative method was developed to isolate three known myrsinoic acids, A(1), B(2) and C(3). Along with, we are reporting the obtention of two new congeners, G(5) and H(6), which their structures were elucidated by NMR and HRMS data. Besides that, two extracts were submitted to affinity assays to accelerate the discovery of AChE ligands. Desorbates were analyzed through LC-HRMS for calculating the affinity ratio (AR). Thus, (1) presented AR = 4.59, therefore was considered a potential ligand.


Subject(s)
Acetylcholinesterase , Molecular Structure , Ligands , Acetylcholinesterase/metabolism , Phytochemicals/isolation & purification , Phytochemicals/chemistry , Cholinesterase Inhibitors/chemistry
4.
Toxicon ; 240: 107626, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38290609

ABSTRACT

Gymnopilins are long chain oligoisoprenoids produced through the condensation of isoprene units from MEV and MEP biosynthetic pathways. In Gymnopilus, these carotenoid-like molecules are recognized as major compounds in some species. In the present study, oligoisoprenoids derived from gymnopilins were dereplicated from Gymnopilus imperialis, a mushroom-forming basidiomycete, using liquid chromatographic coupled with high-resolution mass spectrometry (tandem LC-HRMS/MS) and GNPS. From the dichloromethane extract (Gym-DCM) of G. imperialis we annotated 3 oligoisoprenoids from the GNPS molecular library spectra and 15 analogs from the curation of the molecular networking. Data from NMR spectroscopic of the extract confirmed the annotation of the metabolites. Based on the literature data suggesting the neurotoxic effect of gymnopilins, we investigated the effects of the administering different doses of gymnopilin extracts (1, 4 or 10 mg/kg) and diazepam (4 mg/kg) on the acquisition of object recognition memory (ORM) in mice. By studying novel object recognition memory (ORM), a type of non-aversive memory. ORM was assessed based on the total time of spontaneous exploration of both objects, the discrimination index (DI), and the frequency of contact with both objects. Our present findings reveal, for the first time, that gymnopilins treatment before training modulates ORM in a dose-dependent manner. It is also suggested that differential effects on memory might be related to differential effects on GABAA receptors but do not exclude its effects in other neurotransmitter systems. Another class of secondary metabolites, alkaloids, might modulate AChR, which is essential for maintaining object recognition memory over time.


Subject(s)
Agaricales , Basidiomycota , Mice , Animals , Agaricales/chemistry , Anxiety , Exploratory Behavior
5.
Phytochem Anal ; 35(1): 93-101, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37592443

ABSTRACT

INTRODUCTION: We developed Data Base similarity (DBsimilarity), a user-friendly tool designed to organize structure databases into similarity networks, with the goal of facilitating the visualization of information primarily for natural product chemists who may not have coding experience. METHOD: DBsimilarity, written in Jupyter Notebooks, converts Structure Data File (SDF) files into Comma-Separated Values (CSV) files, adds chemoinformatics data, constructs an MZMine custom database file and an NMRfilter candidate list of compounds for rapid dereplication of MS and 2D NMR data, calculates similarities between compounds, and constructs CSV files formatted into similarity networks for Cytoscape. RESULTS: The Lotus database was used as a source for Ginkgo biloba compounds, and DBsimilarity was used to create similarity networks including NPClassifier classification to indicate biosynthesis pathways. Subsequently, a database of validated antibiotics from natural products was combined with the G. biloba compounds to identify promising compounds. The presence of 11 compounds in both datasets points to possible antibiotic properties of G. biloba, and 122 compounds similar to these known antibiotics were highlighted. Next, DBsimilarity was used to filter the NPAtlas database (selecting only those with MIBiG reference) to identify potential antibacterial compounds using the ChEMBL database as a reference. It was possible to promptly identify five compounds found in both databases and 167 others worthy of further investigation. CONCLUSION: Chemical and biological properties are determined by molecular structures. DBsimilarity enables the creation of interactive similarity networks using Cytoscape. It is also in line with a recent review that highlights poor biological plausibility and unrealistic chromatographic behaviors as significant sources of errors in compound identification.


Subject(s)
Biological Products , Biological Products/chemistry , Magnetic Resonance Spectroscopy/methods , Databases, Factual , Plant Extracts/chemistry , Anti-Bacterial Agents
6.
Chem Biodivers ; 21(3): e202301508, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38092696

ABSTRACT

Dillenia indica (Linn.) has been reported by several biological activities, including anti-inflammatory, antioxidant, antidiabetic, anti-hyperglycemic, antiproliferative, antimutagenic, anticholinesterase, and antimicrobial. In Brazilian traditional medicine, the fruits of D. indica have been used to treat general topical pain and inflammation, but with no scientific validation. Thus, aiming to study its chemical constitution and antinociceptive properties, the crude extract (CE) and fractions obtained from the fruits of D. indica were submitted to an in vivo pharmacological evaluation and a dereplication study by LC-MS/MS analysis, assisted by the Global Natural Product Social Molecular Networking (GNPS). The oral antinociceptive activity of the fruits of D. indica and the possible participation of the opioid and cannabinoid systems were demonstrated in the formalin-induced nociception model. The chemical dereplication study led us to identify several known chemical constituents, including flavonoids, such as caffeoylmalic acid, naringenin, quercetin, and kaempferol. According to literature data, our results are compatible with significant antinociceptive and anti-inflammatory activities. Therefore, the flavonoid constituents of the fruits of D. indica are probably responsible for its antioxidant, anti-inflammatory, and antinociceptive effects mediated by both opioid and cannabinoid systems, confirming its folk use in the treatment and relief of pain.


Subject(s)
Analgesics , Dilleniaceae , Analgesics/chemistry , Analgesics, Opioid/adverse effects , Plant Extracts/chemistry , Antioxidants/pharmacology , Antioxidants/therapeutic use , Chromatography, Liquid , Tandem Mass Spectrometry , Anti-Inflammatory Agents/pharmacology , Pain/drug therapy , Flavonoids/therapeutic use
7.
São Paulo; s.n; s.n; 2024. 122 p tab, graf.
Thesis in Portuguese | LILACS | ID: biblio-1565949

ABSTRACT

Os produtos naturais são uma importante fonte de moléculas com aplicações terapêuticas e biotecnológicas. No entanto, a complexidade inerente às matrizes biológicas e as crescentes taxas de redescoberta de moléculas impõem desafios para a busca por novos compostos bioativos. A exploração de novos espécimes da biodiversidade e a aplicação de ferramentas computacionais são imperativos para a identificação de novas entidades químicas promissoras. Foi proposto catalisar o processo de prospecção química para demonstrar o potencial das cianobactérias brasileiras como fonte de novas moléculas bioativas. Nove linhagens de cianobactérias de água doce/terrestres foram cultivadas, extraídas e fracionadas. Extratos e frações foram testados quanto ao potencial citotóxico contra o microcrustáceo Artemia salina, antiproliferativo contra linhagens celulares de melanoma humano e contra promastigotas de Leishmania (L.) amazonensis. As amostras foram analisadas em paralelo via UPLC-HRMS/MS. Foi criada uma rede molecular através da plataforma GNPS. A desreplicação contou também com o suporte da plataforma DAFdiscovery, ferramenta que, através da fusão de informações dos dados de LC-MS/MS com os metadados contendo informações obtidas dos bioensaios, elenca quais as features se correlacionam com a atividade biológica. A anotação seguida de busca em base de dados foi realizada com auxílio do software SIRIUS. Quatro linhagens de cianobactérias foram selecionadas seguindo essa abordagem devido ao seu potencial ineditismo químico e bioatividade, sendo elas Brasilonema octagenarum, Anagnostidinema amphibium, Nostoc sp. e Komarekiella atlântica


Natural products are an important source of molecules with therapeutic and biotechnological applications. However, the inherent complexity of biological matrices and the increasing rediscovery rates challenge the search for new bioactive compounds. Exploring new specimens of biodiversity and applying computational tools are imperative for identifying promising new chemical entities. In this study, we proposed to catalyze the chemical prospecting process to demonstrate the potential of Brazilian cyanobacteria as a source of new bioactive molecules. Nine strains of freshwater cyanobacteria were cultivated, extracted, and fractionated. Extracts and fractions were tested for cytotoxic potential against the microcrustacean Artemia salina, antiproliferative against human melanoma cell lines, and Leishmania (L.) amazonensis promastigotes. Samples were analyzed in parallel via UPLCHRMS/MS. A molecular network was created using the GNPS platform. Dereplication was guided by DAFdiscovery, a computational tool that, through the fusion of information from LC-MS/MS data with metadata containing information obtained from bioassays, indexed which features correlate with biological activity. Annotation followed by a database search was performed using the SIRIUS software. Brasilonema octagenarum, Anagnostidinema amphibium, Nostoc sp., and Komarekiella atlântica were selected following this approach due to their potential chemical novelty and bioactivity


Subject(s)
Biological Products/analysis , Cyanobacteria/classification , Liquid Chromatography-Mass Spectrometry/methods , Leishmania/classification , Melanoma/classification
8.
Nat Prod Res ; : 1-8, 2023 Dec 03.
Article in English | MEDLINE | ID: mdl-38043103

ABSTRACT

Pterocaulon genus comprises 26 species, half of them have been phytochemical investigations regarding the chemical composition, and coumarins have been considered the chemotaxonomic markers in the genus. Herein Pterocaulon angustifolium DC (Asteraceae), a native plant from Brazil, is investigated for the first time. Twenty-six compounds were isolated from aerial parts of P. angustifolium DC., being 5 triterpenes, 4 phytosterols, 9 flavonoids, 3 phenolic acids, and 5 coumarins. Moreover, a total of 177 compounds were putatively identified using the dereplication technique by UHPLC-HRMS/MS, more than 50% correspond to flavonoids and coumarins. Although 41 different coumarins have already been reported in Pterocaulon genus, 16 were identified for the first time in this study. Crude ethanolic extract and fractions of P. angustifolium were also biologically investigates, and dichloromethane fraction was the most active fraction in the evaluation of antiproliferative, antioxidant, antimicrobial and cholinesterase inhibitory activities.

9.
Adv Exp Med Biol ; 1439: 101-122, 2023.
Article in English | MEDLINE | ID: mdl-37843807

ABSTRACT

Highly selective and sensitive analytical techniques are necessary for microbial metabolomics due to the complexity of the microbial sample matrix. Hence, mass spectrometry (MS) has been successfully applied in microbial metabolomics due to its high precision, versatility, sensitivity, and wide dynamic range. The different analytical tools using MS have been employed in microbial metabolomics investigations and can contribute to the discovery or accelerate the search for bioactive substances. The coupling with chromatographic and electrophoretic separation techniques has resulted in more efficient technologies for the analysis of microbial compounds occurring in trace levels. This book chapter describes the current advances in the application of mass spectrometry-based metabolomics in the search for new biologically active agents from microbial sources; the development of new approaches for in silico annotation of natural products; the different technologies employing mass spectrometry imaging to deliver more comprehensive analysis and elucidate the metabolome involved in ecological interactions as they enable visualization of the spatial dispersion of small molecules. We also describe other ambient ionization techniques applied to the fingerprint of microbial natural products and modern techniques such as ion mobility mass spectrometry used to microbial metabolomic analyses and the dereplication of natural microbial products through MS.


Subject(s)
Biological Products , Metabolomics , Mass Spectrometry/methods , Metabolomics/methods , Metabolome
10.
Adv Exp Med Biol ; 1439: 185-224, 2023.
Article in English | MEDLINE | ID: mdl-37843810

ABSTRACT

The incessant search for new natural molecules with biological activities has forced researchers in the field of chemistry of natural products to seek different approaches for their prospection studies. In particular, researchers around the world are turning to approaches in metabolomics to avoid high rates of re-isolation of certain compounds, something recurrent in this branch of science. Thanks to the development of new technologies in the analytical instrumentation of spectroscopic and spectrometric techniques, as well as the advance in the computational processing modes of the results, metabolomics has been gaining more and more space in studies that involve the prospection of natural products. Thus, this chapter summarizes the precepts and good practices in the metabolomics of microbial natural products using mass spectrometry and nuclear magnetic resonance spectroscopy, and also summarizes several examples where this approach has been applied in the discovery of bioactive molecules.


Subject(s)
Biological Products , Metabolomics/methods , Mass Spectrometry/methods , Magnetic Resonance Spectroscopy/methods
11.
Molecules ; 28(17)2023 Aug 24.
Article in English | MEDLINE | ID: mdl-37687053

ABSTRACT

Salvia hispanica L., commonly known as chía, and its seeds have been used since ancient times to prepare different beverages. Due to its nutritional content, it is considered a dietary ingredient and has been reported with many health benefits. Chia seed components are helpful in cardiovascular disease (CVD) by reducing blood pressure, platelet aggregation, cholesterol, and oxidation. Still, its vasodilator effects on the vascular system were not reported yet. The hexanic (HESh), dichloromethanic (DESh), and methanolic (MESh) extracts obtained from chía seeds were evaluated on an aortic ring ex-vivo experimental model. The vasorelaxant efficacy and mechanism of action were determined. Also, phytochemical data was obtained through 13C NMR-based dereplication. The MESh extract showed the highest efficacy (Emax = 87%), and its effect was partially endothelium-dependent. The mechanism of action was determined experimentally, and the vasorelaxant curves were modified in the presence of L-NAME, ODQ, and potassium channel blockers. MESh caused a relaxing effect on KCl 80 mM-induced contraction and was less potent than nifedipine. The CaCl2-induced contraction was significantly decreased compared with the control curve. Phytochemical analysis of MESh suggests the presence of mannitol, previously reported as a vasodilator on aortic rings. Our findings suggest NO-cGMP pathway participation as a vasodilator mechanism of action of S. hispanica seeds; this effect can be attributed, in part, to the mannitol presence. S. hispanica could be used in future research focused on antihypertensive therapies.


Subject(s)
Salvia hispanica , Vasodilator Agents , Vasodilator Agents/pharmacology , Nitric Oxide , Nifedipine
13.
Phytochem Anal ; 34(7): 869-883, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37403427

ABSTRACT

INTRODUCTION: This study describes the molecular profile and the potential antiviral activity of extracts from Phyllanthus brasiliensis, a plant widely found in the Brazilian Amazon. The research aims to shed light on the potential use of this species as a natural antiviral agent. METHODS: The extracts were analysed using liquid chromatography-mass spectrometry (LC-MS) system, a potent analytical technique to discover drug candidates. In the meantime, in vitro antiviral assays were performed against Mayaro, Oropouche, Chikungunya, and Zika viruses. In addition, the antiviral activity of annotated compounds was predicted by in silico methods. RESULTS: Overall, 44 compounds were annotated in this study. The results revealed that P. brasiliensis has a high content of fatty acids, flavones, flavan-3-ols, and lignans. Furthermore, in vitro assays revealed potent antiviral activity against different arboviruses, especially lignan-rich extracts against Zika virus (ZIKV), as follows: methanolic extract from bark (MEB) [effective concentration for 50% of the cells (EC50 ) = 0.80 µg/mL, selectivity index (SI) = 377.59], methanolic extract from the leaf (MEL) (EC50 = 0.84 µg/mL, SI = 297.62), and hydroalcoholic extract from the leaf (HEL) (EC50 = 1.36 µg/mL, SI = 735.29). These results were supported by interesting in silico prediction, where tuberculatin (a lignan) showed a high antiviral activity score. CONCLUSIONS: Phyllanthus brasiliensis extracts contain metabolites that could be a new kick-off point for the discovery of candidates for antiviral drug development, with lignans becoming a promising trend for further virology research.


Subject(s)
Lignans , Phyllanthus , Zika Virus Infection , Zika Virus , Plant Extracts/pharmacology , Plant Extracts/chemistry , Phyllanthus/chemistry , Antiviral Agents/pharmacology , Lignans/pharmacology , Lignans/chemistry
14.
Nat Prod Res ; : 1-6, 2023 Jun 27.
Article in English | MEDLINE | ID: mdl-37367484

ABSTRACT

In the present study, we have evaluated the cytotoxic activity of 282 extracts from 72 native plant species of the Brazilian Atlantic Forest biome. As a result, Casearia arborea and Sorocea hilarii leaves extracts showed cytotoxic activity against three tumour cell lines tested (B16F10, SW480 and Jurkat). After bioassay-guided fractionation, the bioactive fractions were submitted to the dereplication study via High-performance Liquid Chromatography, connected to High-resolution Mass Spectrometry (HPLC-ESI-QTOF/MS) analysis, combined with a Global Natural Products Social Molecular Networking (GNPS) tool. A combination of bioactivity-guided and dereplication approaches resulted in the putative annotation of 27 clerodane diterpenes and 9 flavonoids as main compounds present in the cytotoxic fractions of C. arborea. Regarding the active fraction of S. hilarii, 10 megastigmans, 17 spirostane steroids derivatives and 2 lignans were putatively identified. In conclusion, Casearia arborea and Sorocea hilarii are potential sources of antitumor compounds.

15.
Phytochem Anal ; 34(4): 385-392, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37128872

ABSTRACT

INTRODUCTION: Natural products and metabolomics are intrinsically linked through efforts to analyze complex mixtures for compound annotation. Although most studies that aim for compound identification in mixtures use MS as the main analysis technique, NMR has complementary advances that are worth exploring for enhanced structural confidence. OBJECTIVE: This review aimed to showcase a portfolio of the main tools available for compound identification using NMR. MATERIALS AND METHODS: COLMAR, SMART-NMR, MADByTE, and NMRfilter are presented using examples collected from real samples from the perspective of a natural product chemist. Data are also made available through Zenodo so that readers can test each case presented here. CONCLUSION: The acquisition of 1 H NMR, HSQC, TOCSY, HSQC-TOCSY, and HMBC data for all samples and fractions from a natural products study is strongly suggested. The same is valid for MS analysis to create a bridged analysis between both techniques in a complementary manner. The use of NOAH supersequences has also been suggested and demonstrated to save NMR time.


Subject(s)
Biological Products , Metabolomics , Magnetic Resonance Spectroscopy/methods , Metabolomics/methods , Complex Mixtures/chemistry
16.
Chem Biodivers ; 20(1): e202200715, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36490384

ABSTRACT

The hydroalcoholic extract of Polygala altomontana (30, 100, and 300 mg/kg, i.g.) showed a dose-dependent antinociceptive action during the inflammatory phase of the formalin test. In addition, the preparation (30 and 300 mg/kg, i.g.) showed anti-hyperalgesic action when tested on a mechanical nociception model. UPLC-ESI-QTOF-MS data indicated the active extract contained phenylpropanoid sucrose esters, glycosylated quercetin derivatives, styrylpyrones, and coumarins. Some identified compounds, including styrylpyrones and coumarins, have previously demonstrated antinociceptive action. The results also show that P. altomontana shows potential for developing pain-relieving herbal remedies and drugs.


Subject(s)
Analgesics , Polygala , Analgesics/pharmacology , Analgesics/therapeutic use , Polygala/chemistry , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Pain/drug therapy , Coumarins/therapeutic use
17.
Nat Prod Res ; 37(11): 1882-1887, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36095034

ABSTRACT

Siparuna brasiliensis is a medicinal plant widely used by indigenous communities of the Amazon rainforest to treat inflammatory diseases and related pathologies. Considering its ethnopharmacological application, it constitutes an important source of biologically active molecules in the development of anti-inflammatory drugs. This study describes a dereplication methodology of the bioactive extract from S. brasiliensis leaves and the evaluation of the anti-inflammatory potential in an in vivo inflammatory model with mice of the BALB/c lineage and in vitro using cell lines, as well as determining the production of an inflammatory mediator. From their charge-to-mass ratios (m/z) and elemental composition obtained through Ultrahigh-resolution mass spectrometry analysis by ESI(-)-Orbitrap MS and chromatographic profile by RP-HPLC-PDA, it was possible to annotate polyphenols with anti-inflammatory properties classified as flavonoids and organic acids. The administration of the extract significantly inhibited carrageenan-induced paw edema and showed effects similar to those of drug dexamethasone without affecting cell viability.


Subject(s)
Plant Extracts , Plants, Medicinal , Mice , Animals , Plant Extracts/chemistry , Anti-Inflammatory Agents/chemistry , Carrageenan/adverse effects , Polyphenols/analysis , Plant Leaves/chemistry , Edema/chemically induced , Edema/drug therapy
18.
Pharmaceutics ; 14(9)2022 Aug 26.
Article in English | MEDLINE | ID: mdl-36145544

ABSTRACT

Momordica charantia L. (Cucurbitaceae) is a plant known in Brazil as "melão de São Caetano", which has been related to many therapeutic applications in folk medicine. Herein, we describe antibacterial activities and related metabolites for an extract and fractions obtained from the leaves of that species. An ethanolic extract and its three fractions were used to perform in vitro antibacterial assays. In addition, liquid chromatography coupled to mass spectrometry and the molecular networking approach were used for the metabolite annotation process. Overall, 25 compounds were annotated in the ethanolic extract from M. charantia leaves, including flavones, terpenes, organic acids, and inositol pyrophosphate derivatives. The ethanolic extract exhibited low activity against Proteus mirabilis (MIC 312.5 µg·mL-1) and Klebsiella pneumoniae (MIC 625 µg·mL-1). The ethyl acetate phase showed interesting antibacterial activity (MIC 156.2 µg·mL-1) against Klebsiella pneumoniae, and it was well justified by the high content of glycosylated flavones. Therefore, based on the ethyl acetate phase antibacterial result, we suggest that M. charantia leaves could be considered as an alternative antibacterial source against K. pneumoniae and can serve as a pillar for future studies as well as pharmacological application against the bacteria.

19.
J Chromatogr A ; 1677: 463211, 2022 Aug 16.
Article in English | MEDLINE | ID: mdl-35810640

ABSTRACT

Syzygium malaccense (L.) Merr. & L.M. Perry is a native tree to Malaysia, but also occurs in other tropical regions of the world, including Brazil. The increasing interest in the consumption of its leaves motivated the investigation of compounds of the plant. Metabolite profiling of S. malaccense leaves was achieved by high-speed countercurrent chromatography (HSCCC) fractionation coupled off-line to electrospray mass-spectrometry (ESI-MS) detection and nuclear magnetic resonance (NMR) analysis. The ethanolic leaf extract was submitted to HSCCC using a three-phase solvent system (TPSS) composed by n-hexane - ethyl acetate - acetonitrile - H2O (2:1:1:1, v/v). The stepwise gradient elution was employed due to the extract's chemical complexity. HSCCC fractions were further analyzed by ESI-MS/MS using a flow injection experiment and by NMR acquiring 1H, HSQC and HMBC spectra. MS based dereplication was achieved by comparing acquired data to those available in public and commercial databases. Results were also correlated to previously isolated compounds described for the Syzygium genus. This process led to the annotation of 90 compounds. The NMR data provided structural confirmation and substitution patterns for some of them. Extract chemical composition is characterized by having flavonoids, benzoic acids, hydroxycinnamic acids, quinic acids, hydrolizable tannins, fatty acids, anacardic acids and others primary metabolites. Most of these compounds were described for the first time in the plant. This approach greatly facilitates phytochemical analysis and could be applied to improve metabolite discovery in other studies.


Subject(s)
Countercurrent Distribution , Syzygium , Chromatography, High Pressure Liquid/methods , Countercurrent Distribution/methods , Magnetic Resonance Spectroscopy , Plant Extracts/chemistry , Plants, Edible , Solvents/chemistry , Spectrometry, Mass, Electrospray Ionization , Tandem Mass Spectrometry/methods
20.
Front Chem ; 10: 800729, 2022.
Article in English | MEDLINE | ID: mdl-35677597

ABSTRACT

The extensive use of medicinal herbs to traditionally treat disease persists for generations, and scientific evidence on plant-derived extracts has indicated their numerous biological activities. The Bauhinia, popular known as cow's paw ("pata de vaca"), with more than 60 native species, are extensively used in Brazilian popular medicine for the control of diabetes. Therefore, in 2009, B. forficata, B. variegata and/or B. affinis were included in the Brazilian National List of Medicinal Plants of Interest to SUS (RENISUS - Brazil). In this context, this work reports the results of the chemical differentiation of B. forficata, B. variegata, B. longifolia, and B. affinis using liquid chromatography coupled to high-resolution mass spectrometry and unsupervised chemometric tools. Chromatographic conditions were optimized by using the design of experiments (DoE) and chromatographic knowledge. Furthermore, the chemical profile of the studied species was analyzed by principal component analysis (PCA) and hierarchical cluster analysis that differentiated the four species of Bauhinia, and 55 compounds were also inferred by MS2 experiments, some of them for the first time in B. affinis. In this manner, this work provides important information that could be used in quality control, development of new pharmaceuticals, and food products based on Bauhinia leaves, as well as to explain ethnomedicinal properties, pharmacological and toxicological actions.

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