Infraspecific Chemical Variability and Metabolomic Profiling by Paper Spray Ionization (PSI-MS) of Averrhoa carambola from Different Brazilian Biomes.

This research focused on the molecular diversity of A. carambola collected from three Brazilian biomes (Cerrado, Amazônia, and Mata Atlântica), whose results revealed significant differences in metabolite profiles among these biomes through PSI-MS analysis. Chemometric analysis provided valuable insights into the clustering patterns and metabolic distinctions. Cerrado and Mata Atlântica biomes exhibited a 70 % similarity, indicating a notable degree of resemblance. In Cerrado, carambolaside A was notably abundant, while carambolaside M was low in Amazônia and moderate in Cerrado samples. Carambolaside B was abundant in Amazônia but relatively low in the Cerrado and Mata Atlântica. In contrast, the Amazônia biome samples appeared to be more dissimilar. In Cerrado, epicatechin, kaempferol, and procyanidin B showed lower abundance, while apigenin, quercetin, myricetin, and rutin displayed moderate levels. Mata Atlântica showed relatively higher levels of kaempferol, quercetin, and rutin. This study indicated the environmental influence on secondary metabolites production in A. carambola fruits.

In vitro antitumor effects of aqueous extract and protease inhibitors from Sterculia striata st. Hil. et naud and metabolite profiling.

The present study aims to assess the cytotoxic effect of the aqueous and protease inhibitors extracts of Sterculia striata on breast cancer cell lines. The in vitro results showed significant reductions in the highest concentrations from the S. striata seed extract for all cell lines. The aqueous extract reduced the viability by up to 35% in the MCF-7, 25% in the 4T1, and 35% in the MDA-MB-231 cell lines. Regarding the protease inhibitor extract, a 50% reduction in cell viability was observed in the MDA-MB-231 at concentration of 333 µg/mL. The aqueous and the protease inhibitor extracts showed mild reduction in the viability of macrophage cell lines. Chemical characterisation analysis revealed several polyphenols such as flavonoids, tannins, phenolic acids, and other secondary metabolites including terpenes, steroids, fatty acids, and organic acids, which may be related to the promising bioactivity observed. The S. striata showed antitumor activity, emphasising its pharmacological potential.

Protease inhibitors characterisation by SDS-PAGE and MALDI-TOF from Alocasia macrorrhizos and their modulation of macrophage immune-inflammatory properties.

This study describes the extraction and identification by electrophoretic and spectrometric techniques of protease inhibitor from the medicinal plant Alocasia macrorrhizos as well as investigates their immunomodulatory properties and cell viability. The A. macrorrhizos tubers were subjected to protease inhibitor extractions and characterised using SDS-PAGE and MALDI-TOF. The protein extracts were assessed for activities trypsin inhibition stoichiometry, haemagglutinating, cell viability, NO and TNF-α production inhibition. Concerning the protease inhibitors analysis through SDS-PAGE, the results showed two bands with 11 and 24 kDa, and the MS analysis detected the ions more intense of m/z 4276.795 and 8563.361 in the roasted protein extract. The IC50 of trypsin inhibition was 0.119 and 0.302 mg L-1 in the roasted and crude tuber, respectively. The protease inhibitors extract from the roasted tubers showed a reduction in the production of NO and TNF-α at concentrations lower than 100 µg mL-1, without a reduction in cell viability.

Assessing the Effectiveness of Chemical Marker Extraction from Amazonian Plant Cupuassu (Theobroma grandiflorum) by PSI-HRMS/MS and LC-HRMS/MS.

Employing a combination of liquid chromatography electrospray ionization and paper spray ionization high-resolution tandem mass spectrometry, extracts from cupuassu (Theobroma grandiflorum) pulp prepared with either water, methanol, acetonitrile or combinations thereof were subjected to metabolite fingerprinting. Among the tested extractors, 100% methanol extracted preferentially phenols and cinnamic acids derivatives, whereas acetonitrile and acetonitrile/methanol were more effective in extracting terpenoids and flavonoids, respectively. And while liquid chromatography- mass spectrometry detected twice as many metabolites as paper spray ionization tandem mass spectrometry, the latter proved its potential as a screening technique. Comprehensive structural annotation showed a high production of terpenes, mainly oleanane triterpene derivatives. of the mass spectra Further, five major metabolites with known antioxidant activity, namely catechin, citric acid, epigallocatechin-3'-glucuronide, 5,7,8-trihydroxyflavanone, and asiatic acid, were subjected to molecular docking analysis using the antioxidative enzyme peroxiredoxin 5 (PRDX5) as a model receptor. Based on its excellent docking score, a pharmacophore model of 5,7,8-trihydroxyflavanone was generated, which may help the design of new antioxidants.

Metabolic profiling by LC-DAD-MS, FTIR, NMR and CE-UV of polyphenols with potential against skin pigmentation disorder.

In traditional Brazilian medicine, tubers extracts from Alocasia macrorrhizos are widely used in the treatment of skin pigmentation disorder. However, studies that evaluate its benefits in the treatment of this disorder are non-existent. Thus, this work aims to investigate the bioactivity of A. macrorrhizos extracts in cell culture and murine model of Vitiligo and correlating with its phenolic profile. The metabolic profiling from the bioactive extracts was obtained by LC-DAD-MS, FTIR, NMR, and CE-UV. The murine model of Vitiligo was induced with 5% hydroquinone in C57BL/6 male mice, which were treated or not with 100 mg/kg of roasted tuber aqueous extract. In Vitiligo model assay was observed hair follicle repigmentation and reduction of the epidermal layer thickness at the histopathological level, in the animals treated with aqueous extract of roasted tubers. The present study provides new molecular insight and scientific evidence on the potential utility of the extract of A. macrorrhizos against Vitiligo.

Dereplication of Siparuna brasiliensis extract with in vivo anti-inflammatory activity.

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.

LC-HRMS/MS-Based Metabolomics Approaches Applied to the Detection of Antifungal Compounds and a Metabolic Dynamic Assessment of Orchidaceae.

The liquid chromatography-mass spectrometry (LC-MS)-based metabolomics approach is a powerful technology for discovering novel biologically active molecules. In this study, we investigated the metabolic profiling of Orchidaceae species using LC-HRMS/MS data combined with chemometric methods and dereplication tools to discover antifungal compounds. We analyze twenty ethanolic plant extracts from Vanda and Cattleya (Orchidaceae) genera. Molecular networking and chemometric methods were used to discriminate ions that differentiate healthy and fungal-infected plant samples. Fifty-three metabolites were rapidly annotated through spectral library matching and in silico fragmentation tools. The metabolomic profiling showed a large production of polyphenols, including flavonoids, phenolic acids, chromones, stilbenoids, and tannins, which varied in relative abundance across species. Considering the presence and abundance of metabolites in both groups of samples, we can infer that these constituents are associated with biochemical responses to microbial attacks. In addition, we evaluated the metabolic dynamic through the synthesis of stilbenoids in fungal-infected plants. The tricin derivative flavonoid- and the loliolide terpenoidfound only in healthy plant samples, are promising antifungal metabolites. LC-HRMS/MS, combined with state-of-the-art tools, proved to be a rapid and reliable technique for fingerprinting medicinal plants and discovering new hits and leads.

Alternative method for microenzymatic inhibition activities monitoring from Baccharis trimera extracts by CZE-UV.

INTRODUCTION: Capillary zone electrophoresis with direct UV detection (CZE-UV) was used to investigate the hypothesis about the extract of Baccharis trimera enzymatic activities as an analytical approach to monitoring the phenomenon. OBJECTIVE: The aim of this work was to investigate enzymatic bioactivities of the hydroalcoholic and infusion extracts of B. trimera through screening evaluation of the inhibition of the enzymes acetylcholinesterase (AChE) and α-glycosidase (α-GLY). METHOD: An alternative approach using CZE-UV to hydroalcoholic and infusion extracts of B. trimera monitoring was applied to evaluate the inhibition ability of the enzymes AChE and α-GLY. The result of the reaction of acetylthiocholine (AThCh) with AChE was thiocholine (TCh) and acetic acid, and from the amount of TCh generated, the AChE inhibition was calculated. For the inhibition study of the two enzymes, the reactions of the extracts were optimised to be performed in situ, inside the capillary column, and the introduction of the solutions was performed through ordered sequential plug injections. RESULTS: Samples extracted with 70% ethanol presented 7.80% inhibition for AChE and 0.51% for α-GLY, while samples extracted with 96% ethanol resulted in 6.89% inhibition for AChE and no inhibition activity for α-GLY. CONCLUSION: In the present work, the potentialities of CZE-UV for the study of hydroalcoholic and infusion extracts of B. trimera were demonstrated. The experimental results were useful for the calculation of the percentage of the inhibition activities of the AChE and α-GLY enzymes.

Metabolic Profiling of Inga Species with Antitumor Activity.

This work evaluated the metabolic profiling of Inga species with antitumor potential. In addition, we described the antigenotoxicity of polyphenols isolated from I. laurina and a proteomic approach using HepG2 cells after treatment with these metabolites. The in vitro cytotoxic activity against HepG2, HT-29 and T98G cancer cell lines was investigated. The assessment of genotoxic damage was carried out through the comet assay. The ethanolic extract from I. laurina seeds was subjected to bioassay-guided fractionation and the most active fractions were characterized. One bioactive fraction with high cytotoxicity against HT-29 human colon cancer cells (IC50 = 4.0 µg mL-1) was found, and it was characterized as a mixture of p-hydroxybenzoic acid and 4-vinyl-phenol. The I. edulis fruit peel (IC50 = 18.6 µg mL-1) and I. laurina seed (IC50 = 15.2 µg mL-1) extracts had cytotoxic activity against the cell line T98G, and its chemical composition showed a variety of phenolic acids. The chemical composition of this species indicated a wide variety of aromatic acids, flavonoids, tannins, and carotenoids. The high concentration (ranging from 5% to 30%) of these polyphenols in the bioactive extract may be responsible for the antitumor potential. Regarding the proteomic approach, we detected proteins directly related to the elimination of ROS, DNA repair, expression of tumor proteins, and apoptosis.

Evaluation of Antioxidant Potential of Commercial Cinnamon Samples and Its Vasculature Effects.

Growing concerns on free radicals are the oxidative processes associated with physiological damage. The consumption of functional foods and use of plants with antioxidant capacity are widespread. Given the importance of determining antioxidant capacity in relation to the therapeutic effect, this study was aimed at evaluating cinnamon extract (Cinnamomum sp.) in commercial samples by spectrophotometric and voltammetric methods and assessing the vascular activity of some samples. The spectrophotometric methods performed were DPPH (1,1-diphenyl-2-picrihydrazine), ABTS (2,21-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)), and Folin-Ciocalteu radical sequestration assays. For the electrochemical experiments, a three-electrode system was used, consisting of carbon paste electrode, platinum wire, and Ag/AgCl/KClsat, representing the working, auxiliary, and reference electrodes, respectively. The electroanalytical methods used were differential pulse, square wave, and cyclic voltammetries. The extracts were prepared in hydroalcoholic solution. A calibration curve with gallic acid was calculated to quantify their equivalent amounts in the analyzed extract. The correlation between the electrochemical approach and the total phenols calculated by the ABTS, DPPH, and Folin-Ciocalteu methods was 0.63, 0.7, and 0.73, respectively, with 1 being an ideal directly proportional correlation. The correlation between spectrophotometric methods was 0.83. A biosensor was developed in a carbon paste electrode using the enzyme laccase, obtained by the fungus Marasmiellus colocasiae. It was observed that the antioxidant profile of the cinnamon samples had an analytical sign improvement of up to 4 times when compared with the electrode without the modification. The samples were analyzed by mass spectrometer, and the main chemical markers found were coumarin, cinnamaldehyde, and eugenol. Pharmacological trials showed that these samples also induce a significant vasorelaxant effect associated to antioxidant potential on vascular injury induced by oxidative stress. Thus, cinnamon showed a high antioxidant capacity, in agreement with the results obtained in other studies, emphasizing its importance as a functional food.

Mass spectrometry applied to diagnosis, prognosis, and therapeutic targets identification for the novel coronavirus SARS-CoV-2: A review.

Mass spectrometry (MS) has found numerous applications in medicine and has been widely used in the detection and characterization of biomolecules associated with viral infections such as COVID-19. COVID-19 is a multisystem disease and, therefore, the need arises to carry out a careful and conclusive assessment of the pathophysiological parameters involved in the infection, to develop an effective therapeutic approach, assess the prognosis of the disease, and especially the early diagnosis of the infected population. Thus, the urgent need for highly accurate methods of diagnosis and prognosis of this infection presents new challenges for the development of laboratory medicine, whose methods require sensitivity, speed, and accuracy of the techniques for analyzing the biological markers involved in the infection. In this context, MS stands out as a robust analytical tool, with high sensitivity and selectivity, accuracy, low turnaround time, and versatility for the analysis of biological samples. However, it has not yet been adopted as a frontline clinical laboratory technique. Therefore, this review explores the potential and trends of current MS methods and their contribution to the development of new strategies to COVID-19 diagnosis and prognosis and how this tool can assist in the discovery of new therapeutic targets, in addition, to comment what could be the future of MS in medicine.

Phytochemical, metabolic profiling and antiparasitic potential from Inga semialata leaves (Fabaceae).

Natural Products phytochemical provide a rich source for therapeutic discovery and has led to the development of many drugs. Thus, the aim of this study was to obtaining a metabolic profiling from ethanol extract of Inga semialata leaves (EEIS) selected by bioassay antimalarial and nematostatic and identify metabolites in mixture by co-injection experiments and NMR spectroscopy. The chemical composition of this species indicated a wide variety of aromatic acids (vanillic acid, 3,4,5-trimethoxy benzoic acid, gallic acid, methyl gallate, p-coumaric acid and ferulic acid), flavonoids (quercetin, myricetin-3-O-rhamnoside and myricetin-3-O-(2"-O-galloyl)-α-rhamnopyranoside), triterpenes (lupeol, α-amyrin, friedelin and oleanolic acid) and the 2-hydroxyethyl-dodecanoate. The antimalarial assay showed that the I. semialata n-hexane fraction presented higher inhibition percentage than the Chloroquine standard and may be considered a potential source of compounds with antimalarial activity while the EEIS and its fractions showed nematostatic potential below 17% in the assay of nematostatic evaluation against the parasite Meloidogyne incognita.

Dereplication of terpenes and phenolic compounds from Inga edulis extracts using HPLC-SPE-TT, RP-HPLC-PDA and NMR spectroscopy.

Inga edulis is traditionally used as anti-inflammatory and antidiarrheal and has been investigated as potential sources of biologically active natural products. In this study, dereplication strategy using HPLC-SPE-TT, RP-HPLC-PDA and NMR spectroscopy was employed, and this resulted in the identification of sixteen compounds from the leaves extract of I. edulis, including four triterpenes (lupeol, α-amirin, olean-18-ene acid and frideline), three flavonoids, eight phenolic acids, an anthocyanin derived from delphinidin-3-glycoside and a mixture of five acylated anthocyanins. The chemical identification was performed based on NMR data, chemosystematics aspects, UV spectra and by comparison with the retention time and UV spectra of authentic standards. The metabolic profile of the species indicated the presence of phenolic compounds as major constituents justifying its strong antioxidant potential performed in ß-carotene test. The techniques used have shown effective strategies for the early detection of active natural products from plant extracts, as these approaches are still crucially absent.[Formula: see text].

Medicinal Plants from Brazilian Cerrado Biome: Potential sources of new anti-inflammatory compounds and antitumor agents on Ehrlich carcinoma.

This work describes a pharmacological screening of Brazilian medicinal plants through their anti-inflammatory and cytotoxicity activities. Cytotoxicity activity of Mouriri elliptica and Alchornea glandulosa as well as the drugs celecoxib and doxorubicin were evaluated in cultures of peritoneal macrophages. The immune system influence of these samples was analyzed by determining production/inhibition of NO, production of tumor necrosis factor-α and production of interleukin-10. Regarding the production/inhibition of NO, there was NO production by M. elliptica and NO inhibition when the cells were exposed to A. glandulosa; Macrophages generally produce more NO, plus TNF-α and less IL-10, when associated to the tumor phenomenon, characterizing the inflammation involved in cancer. A. glandulosa showed anti-inflammatory effect, inhibited NO production and it was associated with low TNF-α production, although not as low as the macrophages associated with celecoxib and doxorubicin. These cytokines were not different in animals with tumor. Celecoxib confirms its anti-inflammatory action by markedly inhibiting NO and TNF-α, but also inhibiting IL-10 which is an anti-inflammatory cytokine. Doxorubicin inhibited NO in a higher percentage in the group of animals with tumor, although the literature reports that this drug stimulates the production of NO and this collaborates with its cytotoxic effect.

Effectiveness of different methods for the extraction of principle actives and phytochemicals content in medicinal herbals / Efectividad de diferentes métodos para la extracción de principios activos y contenido de fitoquímicos en hierbas medicinales

In this present study, we investigated the influence of various extraction methods including maceration, sonication, infusion, decoction, and microwave extraction, on the chemical and biological potential of phytochemicals extracted from three medicinal plants (Ageratum conyzoides, Plantago majorand Arctium lappa L). The results were subsequently analyzed by variance analysis. Our results suggested that sonication is the most effective extraction method among the five methods tested herein, for the extraction of phytochemicals that have a high antioxidant potential and high phenolic content. The three plants employed for this study had a high concentration of flavonoids and phenolics which was compatible with the chemosystematics of the species. All the samples possessed a Sun Protection Factor (SPF) of less than 6. Interestingly, a maximum reaction time of approximately 20 min was noted for the complexation of AlCl3 with the flavonoids present in the phytochemical extract during analyses of the kinetic parameters. We finally identified that the Ageratum conyzoides extract, prepared by sonication, possessed a significant pharmacological potential against hepatocarcinoma tumour cells, whose result can guide further studies for its therapeutic efficacy.

En el presente estudio, investigamos la influencia de varios métodos de extracción, incluyendo maceración, sonicación, infusión, decocción y extracción por microondas, sobre el potencial químico y biológico de los fitoquímicos extraídos de tres plantas medicinales (Ageratum conyzoides, Plantago majory Arctium lappa L). Los resultados se analizaron posteriormente mediante análisis de varianza. Nuestros resultados sugieren que la sonicación es el método de extracción más eficaz entre los cinco métodos aquí probados, para la extracción de fitoquímicos que tienen un alto potencial antioxidante y un alto contenido fenólico. Las tres plantas empleadas para este estudio tenían una alta concentración de flavonoides y fenólicos que era compatible con la quimiosistemática de las especies. Todas las muestras poseían un factor de protección solar (SPF) menor a 6. Curiosamente, se observó un tiempo máximo de reacción de aproximadamente 20 min para la complejación de AlCl3con los flavonoides presentes en el extracto fitoquímico durante los análisis de los parámetros cinéticos. Finalmente, identificamos que el extracto de Ageratum conyzoides, elaborado por sonicación, posee un importante potencial farmacológico frente a las células tumorales del hepatocarcinoma, cuyo resultado puede orientar nuevos estudios sobre su eficacia terapéutica.

Miconia albicans and Curcuma longa herbal medicines positively modulate joint pain, function and inflammation in patients with osteoarthritis: a clinical study.

This study aims to evaluate the analgesic and modulating effect of Curcuma longa and Miconia albicans herbal medicines in knee's osteoarthritis (OA) treatment. This longitudinal study evaluated 24 patients with OA. The patients were divided into three groups: ibuprofen (1200 mg/day), C. longa (1000 mg/day) and M. albicans (1000 mg/day). The medications were applied orally for 30 days. The synovial fluid of the knee joint was collect at the first (day 0) and the last medical (day 30) consultation. The groups treated with herbal medicines presented the same results when compared to Ibuprofen. The comparison of the means of Total WOMAC for M. albicans before and after treatment presented a statistically significant difference (mean day 0 = 57.19; mean day 30 = 31.02) as well as variation of Total WOMAC for C. longa (mean day 0 = 54.79; mean day 30 = 37.08). The WOMAC Total and the VASP were compared, it was found that there was a significant decrease in the means in the C. longa and M. albicans groups, as well as in the Ibuprofen group after treatment. The study demonstrated that the treatment of knee OA with C. longa or M. albicans positively interferes with patients pain and functionality, decreased WOMAC and VASP scores, leading to functional improvement of these patients. This is the first clinical study demonstrating the analgesic and anti-inflammatory effect on knee osteoarthritis from M. albicans comparable to Ibuprofen drug.

Cecropia hololeuca: A new source of compounds with potential anti-inflammatory action.

Our objective is to investigate the phytochemical components, antioxidant capacity and in vitro and in vivo anti-inflammatory action from Cecropia hololeuca bark aqueous extract (AECh). The chemical characterization of AECh was performed through CE-UV, FTIR and NMR Spectroscopy. In vitro assays were performed with the AECh on murine macrophages J774A.1 cells in order to analyse cell viability, NO, TNF-α and IL-1ß productions and the in vivo anti-inflammatory potential in acute carrageenan paw oedema in mice. The AECh showed a decrease in the production of NO, TNF-α and IL-1ß, without altering the cell viability and reduction of the paw thickness in the 2nd, 3rd and 4th hour. The extract presented 72% free radical scavenging, 0.60% flavonoid content and showed the presence of gallic acid, caffeic acid and catechin as major constituents. The C. hololeuca bark extract showed important antioxidant and anti-inflammatory activity, emphasizing the industrial and pharmacological potential of this plant.

In vitro and in vivo evaluation of anti-inflammatory activity and free radical scavenging potential of leaves extract from Anadenanthera colubrina.

The present study highlights the antioxidant and anti-inflammatory activities from Anadenanthera colubrina leaves ethanolic extract (EEAc) and its phytochemical profile. The chemical profile of EEAc was determined and in vitro free radical scavenging potential, cell viability in RAW 264.7 and in vitro and in vivo anti-inflammatory activity were evaluated. The analysis of EEAc showed several phenolic compounds such as tannins and phenolic acids. The high antioxidant potential observed is possibly due to its high phenolic content. The EEAc (500 mg kg-1) showed an in vivo effect at the same level of dexamethasone; in vitro, at 50 µg mL-1, inhibited approximately 80% of nitric oxide production concentration, showed an inhibition of more than 50% of TNF-α production and presented high cell viability. The results show that A. colubrina leaves are an important source of phytochemicals that possesses antioxidant and anti-inflammatory properties.

Antifungal activity of extracts and phenolic compounds from Deguelia duckeana

ABSTRACT Candida spp. is associated with almost 80% of all nosocomial fungal infections and is considered a major cause of blood stream infections. In humans, Cryptococcosis is a disease of the lungs caused by the fungi Cryptococcus gattii and Cryptococcus neoformans. It can be potentially fatal, especially in immune-compromised patients. In a search for antifungal drugs, Deguelia duckeana extracts were assayed against these two fungi and also against Candida albicans, which causes candidiasis. Hexane branches and CH2Cl2 root extracts as well as the substances 4-hydroxylonchocarpine, 3,5,4′-trimethoxy-4-prenylstilbene and 3′,4′-methylenedioxy-7-methoxyflavone were assayed to determine the minimal inhibitory concentration. Phytochemical study of CH2Cl2 root and hexane branch extracts from D. duckeana A.M.G. Azevedo, Fabaceae, resulted in the isolation and characterization of nine phenolic compounds: 4-hydroxyderricine, 4-hydroxylonchocarpine, 3′,4′,7-trimethoxy-flavonol, 5,4′-dihydroxy-isolonchocarpine, 4-hydroxyderricidine, derricidine, 3,5,4′-trimethoxy-stilbene, 3′,4′,7-trimethoxyflavone and yangambin. The only active extract was a CH2Cl2 root showing minimal inhibitory concentration 800 µg/ml against C. gattii, and the investigation of compounds obtained from this extract showed that 4-hydroxylonchocarpine was active against all three fungi (C. neoformans, C. gattii and C. albicans). These results suggest that D. duckeana extracts have potential therapeutic value for the treatment of pathogenic fungi.

Isolation of Flavonoids from Deguelia duckeana and Their Effect on Cellular Viability, AMPK, eEF2, eIF2 and eIF4E.

Preparations of Deguelia duckeana, known in Brazil as timbó, are used by indigenous people to kill fish. Reinvestigation of its extracts resulted in the isolation and identification of 11 known flavonoids identified as 3,5,4'-trimethoxy-4-prenylstilbene (1), 4-methoxyderricidine (2), lonchocarpine (3), 4-hydroxylonchocarpine (4), 4-methoxylonchocarpine (5), 5-hydroxy-4',7-dimethoxy-6-prenylflavanone (6), 4'-hydroxyisolonchocarpine (7), 4'-methoxyisolonchocarpine (8), 3',4',7-trimethoxyflavone (9), 3',4'-methylenedioxy-7-methoxyflavone (10), and 2,2-dimethyl-chromone-5,4'-hydroxy-5'-methoxyflavone (11). Except for 1, 3, and 4 all of these flavonoids have been described for the first time in D. duckeana and the flavanone 6 for the first time in nature. Compounds 2, 3, 4, 7, 9, and 10 were studied for their potential to induce cell death in neuronal SK-N-SH cells. Only the chalcone 4 and the flavanone 7 significantly induced lactate dehydrogenase (LDH) release, which was accompanied by activation of caspase-3 and impairment of energy homeostasis in the MTT assay and may explain the killing effect on fish. Interestingly, the flavone 10 reduced cell metabolism in the MTT assay without inducing cytotoxicity in the LDH assay. Furthermore, the flavonoids 2, 3, 4, 7, and 10 induced phosphorylation of the AMP-activated protein kinase (AMPK) and the eukaryotic elongation factor 2 (eEF2). The initiation factor eIF4E was dephosphorylated in the presence of these compounds. The initiation factor eIF2alpha was not affected. Further studies are needed to elucidate the importance of the observed effects on protein synthesis and potential therapeutic perspectives.