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Although swarming motility and biofilms are opposed collective behaviors, both contribute to bacterial survival and host colonization. Pseudovibrio bacteria have attracted attention because they are part of the microbiome of healthy marine sponges. Two-thirds of Pseudovibrio genomes contain a member of a nonribosomal peptide synthetase-polyketide synthase gene cluster family, which is also found sporadically in Pseudomonas pathogens of insects and plants. After developing reverse genetics for Pseudovibrio, we isolated heptapeptides with an ureido linkage and related nonadepsipeptides we termed pseudovibriamides A and B, respectively. A combination of genetics and imaging mass spectrometry experiments showed heptapetides were excreted, promoting motility and reducing biofilm formation. In contrast to lipopeptides widely known to affect motility/biofilms, pseudovibriamides are not surfactants. Our results expand current knowledge on metabolites mediating bacterial collective behavior.

Protium Burm. f. (Burseraceae) is well known in the Brazilian Amazon for its diversity of species, though some of them are difficult to identify based on only morphological characteristics. We investigated the species Protium puncticulatum J.F. Macbr. and Protium tenuifolium (Engl.) Engl. in relation to their chemical constituents and some biological aspects. The phytochemical study of the hexane extract from the trunk of P. puncticulatum led to the identification of a mixture of triterpenes: α, β-amyrin (1 and 2), and lupeol (3); the methanolic extract gave the lignans 7-oxo-parabenzolactone (4) and 7’-hydroxy-9α-methylcubebin (5); this last lignan showed a MIC of 320 μg/mL for Candida albicans and 160 μg/mL for Cryptococcus neoformans and C. gattii. The hexane extract from the branches of P. tenuifolium also provided a mixture of α and β-amyrin (1, 2); the methanolic extract gave dimeric alkylresorcinols named integracin B (6) and integracin A (7). Analyses of anatomical characteristics confirmed the identity of the species Protium tenuifolium (Engl.) Engl. Essential oils obtained via hydrodistillation from the fresh bark of the trunk of P. tenuifolium showed a predominance of the monoterpenes limonene (56.17%), α-phellandrene (16.22%) and ρ-cymene (10.52%). This study is important since it increases knowledge on the volatile and non-volatile chemical constituents of the woody parts of two species of Protium from the Amazon.

Species from the Ocotea genus have shown scientific evidence of anti-inflammatory activity through a promising mechanism of action. This study is the first in vivo evaluation of the anti-inflammatory potential and mechanism of action of extracts and essential oils from the leaves and bark of O. diospyrifolia. We isolated and identified compounds from the leaf and bark extracts and chemically characterized these extracts by ultra high-performance liquid chromatography–high-resolution mass spectrometry (UPLC-HRMS). Additionally, the essential oils were characterized by gas chromatography–mass spectrometry (GC–MS). Nine compounds (1-9) were isolated; among them, a new compound (9) was elucidated as 6aS,7S-(-)-11-hydroxy-7-methoxy-1,2-methylenedioxy-aporphine, named as diospirifoline. The aporphine substitution pattern found in diospirifoline, with substitution at C-7, was identified for first time in the Ocotea genus. Mururin A(1) and salsoline (5) were also isolated for the first time in this genus. The biosynthetically linked alkaloids coclaurine (7), reticuline (6), and isoboldine (8) were found to be 6aR-(-) isomers, which is different from the 6aS-(+) isomers that are most often found in other Ocotea spp. UPLC-HRMS analysis detected various classes of compounds in the leaf and bark extracts, such as flavonolignans, flavonoids, chlorogenic acids, alkaloids, and many other unidentified compounds. The GC–MS analysis revealed that both leaf and bark essential oils contained α-phellandrene as the major compound and that the chemotaxonomic marker of the Lauraceae family, the phenylpropanoid safrole, was not detected. Furthermore, some of the compounds identified in the extracts and essential oils have known anti-inflammatory activities, such as 5-caffeoylquinic acid, quercitrin, α-humulene, and (E)-caryophyllene. Indeed, the leaf extract, its ethyl acetate fraction, and the essential oils showed in vivo anti-inflammatory activity through the dual inhibition of edema and neutrophil recruitment, suggesting the inhibition of main inflammatory pathways. This mechanism of action is associated with a better efficacy and safety profile than that of the currently available anti-inflammatory drugs. The extract and essential oils of O. diospyrifolia showed high chemical diversity and a promising anti-inflammatory mechanism of action; thus, clearly indicating that this species should be further investigated.

Fabaceae is represented in the Amazon region by a high diversity of species and genera that have economic and agroecological importance; however, there is a lack of phytochemical studies. Using LC-DAD-SPE/NMR, analyses of fractions of the methanolic extract from wood residues were performed, and a bipterocarpan (medicarpine-7-O-7′′ secundiflorol I) was identified for the first time. In addition, the known flavonoids 7,3′-dihydroxy-4′-methoxypterocarpan, nissolin, medicarpin, and biochanin A from Andira parviflora Ducke heartwood, the flavonoids taxifolin, butin, 3-methoxyquercetin, and a new derivative of menthiafolic acid (dapaznide) from Inga alba (Sw.) Willd. trunk wood were also identified. Thus, this study has brought new information on the secondary metabolism of both forest species, as well as adding to our knowledge regarding their wood residues.

Sickle cell anaemia (SCA) is a debilitating genetic haemoglobinopathy predominantly affecting the disenfranchised strata of society in Africa and the Americas. The most common pharmacological treatment for this disease is the administration of hydroxycarbamide (HC) for which questions remain regarding its mechanism of action, efficacy and long-term toxicity specifically in paediatric individuals. A multiplatform metabolomics approach was used to assess the metabolome of plasma samples from a population of children and adolescents with SCA with and without HC treatment along with non-SCA individuals. Fifty-three metabolites were identified by ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS) and 1 H nuclear magnetic resonance (NMR) with a predominance of membrane lipids, amino acids and organic acids. The partial least-squares discriminant analysis (PLS-DA) analysis allowed a clear discrimination between the different studied groups, revealing clear effects of the HC treatment in the patients' metabolome including rescue of specific metabolites to control levels. Increased creatine/creatinine levels under HC treatment suggests a possible increase in the arginine pool and increased NO synthesis, supporting existing models for HC action in SCA. The metabolomics results extend the current knowledge on the models for SCA pathophysiology including impairment of Lands' cycle and increased synthesis of sphingosine 1-phosphate. Putative novel biomarkers are suggested.

Metabolomics analysis detected tambjamine alkaloids in aqueous and EtOAc extracts of the marine invertebrates Virididentula dentata, Tambja stegosauriformis, Tambja brasiliensis, and Roboastra ernsti. Among several tambjamines, the new amino acid derivatives tambjamines M-O (17-19) were identified by Marfey's advanced analysis, UPLC-MS/MS analyses, and total synthesis. The tambjamine diversity increased from the bryozoan V. dentata to its nudibranch predators T. stegosauriformis and T. brasiliensis and attained a higher diversity in R. ernsti, the nudibranch that preys upon T. stegosauriformis and T. brasiliensis. The total tambjamine content also increases among the trophic levels, probably due to biomagnification. Tambjamines A (1), C (3), and D (4) are the major metabolites in the tissues of V. dentata, T. stegosauriformis, T. brasiliensis, and R. ernsti and are likely the main chemical defenses of these marine invertebrates.

Herein reported are results of the chemical and biological investigation of red propolis collected at the Brazilian Northeast coastline. New propolones A-D (1-4), with a 3-{3-[(2-phenylbenzofuran-3-yl)methyl]phenyl}chromane skeleton; propolonones A-C (5-7), with a 3-[3-(3-benzylbenzofuran-2-yl)phenyl]chromane skeleton; and propolol A (8), with a 6-(3-benzylbenzofuran-2-yl)-3-phenylchromane skeleton, were isolated as constituents of Brazilian red propolis by cytotoxicity-guided assays and structurally identified by analysis of their spectroscopic data. Propolone B (2) and propolonone A (5) display significant cytotoxic activities against an ovarian cancer cell line expressing a multiple drug resistance phenotype when compared with doxorubicin.

Ruthenium(II) complexes (Ru1-Ru5), with the general formula [Ru(N-S)(dppe)2]PF6, bearing two 1,2-bis(diphenylphosphino)ethane (dppe) ligands and a series of mercapto ligands (N-S), have been developed. The combination of these ligands in the complexes endowed hydrophobic species with high cytotoxic activity against five cancer cell lines. For the A549 (lung) and MDA-MB-231 (breast) cancer cell lines, the IC50 values of the complexes were 288- to 14-fold lower when compared to cisplatin. Furthermore, the complexes were selective for the A549 and MDA-MB-231 cancer cell lines compared to the MRC-5 nontumor cell line. The multitarget character of the complexes was investigated by using calf thymus DNA (CT DNA), human serum albumin, and human topoisomerase IB (hTopIB). The complexes potently inhibited hTopIB. In particular, complex [Ru(dmp)(dppe)2]PF6 (Ru3), bearing the 4,6-diamino-2-mercaptopyrimidine (dmp) ligand, effectively inhibited hTopIB by acting on both the cleavage and religation steps of the catalytic cycle of this enzyme. Molecular docking showed that the Ru1-Ru5 complexes have binding affinity by active sites on the hTopI and hTopI-DNA, mainly via π-alkyl and alkyl hydrophobic interactions, as well as through hydrogen bonds. Complex Ru3 displayed significant antitumor activity against murine melanoma in mouse xenograph models, but this complex did not damage DNA, as revealed by Ames and micronucleus tests.

The Babassu nut (Orbignya phalerata Mart.) mesocarp is traditionally transformed to flour and consumed in some Brazilian areas for its attributed medicinal activity; however, its chemical properties remain to be elucidated. The present work aimed at analyzing the babassu mesocarp phytochemical constituents. Babassu nut samples were collected in the Brazilian Amazon, and their mesocarps were prepared and macerated in different solvents. The chromatographic fractionation of selected methanol extracts yielded three fractions, A-5, A-6, and B-1 that were characterized with high resolution methods. Fraction A-5 was characterized through GC/MS as a fatty acid mixture with predominance of eicosanoic (38.67 %) and 11-octadecanoic (21.71 %) acids. Fraction A-6 was characterized by the presence of three phytosteroids (32.02 %), sesquiterpene (nerolidol; 24.89 %), and diterpene (17-acetoxy-19-kauranal; 15.17 %). The 1H and 13C NMR spectra on fraction A-6 showed characteristic chemical shifts for its compounds. Compound B-1 was identified as ergostanol-3-benzoate based on NMR experiments in one and two dimensions. These results constitute the first identification of babassu mesocarp chemical constituents in 1 and 2-dimensions, paving the way to understanding its role in popular medicine.

The genus Bauhinia belongs to the family Fabaceae and comprises about 18,000 known species in the world. In Brazil, approximately more than 60 native species of Bauhinia are found. Bauhinia leaves tea infusion or other preparations have been widely used in the Brazilian popular medicine for treatment of several illnesses. Therefore, this work aims to a better understanding of Bauhinia longifolia to provide a valuable database for its quality control, pharmacological and toxicological studies. For the chemical analysis, a liquid chromatography-high resolution quadrupole-time of flight mass spectrometer method was applied to evaluate the chemical profile of Bauhinia longifolia ethanolic leaves extracts, allowing for the identification of 75 compounds comprising chemical classes of phenolic acids, proanthocyanidins, and O-glycosides flavonoids. Most polyphenols were identified for the first time in this specie. In addition, six compounds were isolated and fully identified by liquid chromatography hyphenate to solid phase extraction and nuclear magnetic resonance. Herein, myricitrin, juglanin, afzelin, and bauhiniastatin 2 are reported for the first time for Bauhinia longifolia. Bauhiniastatin 2 has been reported to display anticancer properties towards several cancer cell lines. The chemical profile herein described for the ethanolic leaves extract of Bauhinia longifolia provided essential information of this Brazilian native species.

Nowadays, microwave-assisted procedures using closed vessels with thermal, chemical, and mechanical resistance are the state-of-the-art for efficient digestion of samples. Safety issues related to sample reactivity should be considered and analytical throughput is also a critical parameter. The choice of a specific vessel for a target application is not trivial and simple experiments are presented here for rice flour and bovine liver samples to illustrate effects of vessel design on digestion performance. Despite using the same heating program, the residual carbon contents varied from 22 to 67% to bovine liver digests and from 7 to 96% to rice flour digests. Quantitative recoveries were obtained for most analytes. Low recoveries were observed mainly for Ca and Fe. Analytical performance is related to different sizes, shapes and the gradient of temperature for each model of digestion vessel. It was demonstrated that taller vessels improved regeneration of nitric acid.

Croton grewioides Baill. popularly known as “canelinha” or “canelinha-de-cheiro” has been used for the treatment of influenza, antitussive, febrifuge and headache; however, the study of its phytochemical composition is limited. The aim of this study was to investigate the effect of the extraction method and seasonality through leaf extracts of four accessions of Croton grewioides by fingerprint chromatograms aided by principal component analysis to analyze the differences and similarities among the samples. We aimed also to provide chemical characterization of isolated secondary metabolites using semi-preparative liquid chromatography. The results showed that only the chemical profile of the methanolic extracts of accessions 101 and 113 were influenced by the seasonality. For the first time, four flavonoids were isolated through semi-preparative chromatography in this species, characterized as quercetin 3-O-β-D-galactopyranosyl-(1→2)-α-L-rhamnopyranoside-(1→6)-α-L-rhamnopyranoside (1), quercetin 3-O-β-D-galactopyranosyl-(1→2)-α-apiopyranoside-(1→6)-α-L-rhamnopyranoside (2), quercetin 3-O-glucopyranoside (3) and 3-O-methyl-quercetin (4), the flavonoid (2) has been recognized as a new triglycosylated derivative.

Made available in DSpace on 2021-06-25T11:04:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Alginate only finds industrial applicability after undergoing a bleaching process to improve its visual appearance. Box-Behnken Design was used to optimize bleaching parameters (time, oxygen flow and temperature) for sodium alginate (SA) extracted from seaweeds using ozone as the bleaching agent. The optimal conditions (oxygen flow 2 L/min for 35 min at 25 °C) resulted in an ozone-bleached SA with a mannuronic/guluronic acids ratio of 0.70, viscosity-average molecular weight of 66.30 kDa and dynamic viscosity of 1.39 mPa.s, aligned to strong and brittle gels formation, which are potentially suitable for hydrogels and bioink application. Results indicated that ozonation caused depolymerization of the SA chain. Colorimetric parameters showed that ozone has a great bleaching efficacy. The bleached sample presented high antioxidant capacity, highlighting that discoloration by ozone might have minimal effects on the bioactive compounds which are valuable ingredients for food-based products. São Paulo State University (UNESP) Biological Sciences Department University of São Paulo (USP) Food Engineering Department Federal University of Sao Carlos (UFSCAR) Chemistry Department São Paulo State University (UNESP) Biological Sciences Department FAPESP: 2014/22952-6

Collective behavior is a common feature of life. Although swarming motility and biofilms are opposed collective behaviors, both contribute to bacterial survival and host colonization. We have identified a link between motility/biofilms and a nonribosomal peptide synthetase-polyketide synthase gene cluster family (ppp) conserved in Pseudovibrio and Pseudomonas Proteobacteria known to interact with diverse eukaryotes. After developing reverse genetics for Pseudovibrio, we discovered two pseudovibriamide families, heptapeptides with a reversal in chain polarity via an ureido linkage 1-6 and related nonadepsipeptides 7-12. Imaging mass spectrometry showed that 1 was excreted whereas 7 was colony-associated. Deletion of pppA abolished production of 1-12 leading to reduced motility and increased biofilm production. pppD mutants that produced only 1-6 showed motility comparable to the wild-type and reduced biofilm formation, indicating that the excreted heptapeptides play a role in promoting motility. In contrast to lipopeptides widely known to affect swarming and biofilms, pseudovibriamides are not surfactants. Our results expand current knowledge on metabolites mediating bacterial collective behavior. Moreover, the establishment of reverse genetics will enable future exploration of the ecological and biotechnological potential of Pseudovibrio bacteria which have been proposed to contribute to marine sponge health.SignificanceBacteria contribute to health and disease of plants and animals. Specialized metabolites produced by bacteria are important in mediating their behavior and the colonization of their hosts. We have identified a conserved gene cluster family in Pseudovibrio and Pseudomonas bacteria known to colonize marine animals and terrestrial plants, respectively. Using Pseudovibrio as a model, we show the encoded metabolites, which we termed pseudovibriamides, promote motility and decrease biofilms. In contrast to lipopeptides widely known to affect motility/biofilms, pseudovibriamides are not surfactants, but instead are linear peptides with a reversal in chain polarity. The discovery of pseudovibriamides expands current knowledge of bacteria collective behavior. The establishment of reverse genetics will enable exploration of the ecological and biotechnological potential of Pseudovibrio bacteria.ClassificationBiological Sciences, Microbiology

Although many copper-based antimicrobial compounds have been developed to control pathogenic bacteria and fungi in plants and applied for crop protection, there is evidence that several plant pathogens have developed resistance to copper-based antimicrobial compounds, including some Xanthomonas species. Xylella is a bacterial genus belonging to the Xanthomonas family; and X. fastidiosa, which is responsible for citrus variegated chlorosis (CVC) in sweet orange, may develop resistance to one or more copper-based antimicrobials. Because of the time required for the development and approval of new antimicrobials for commercial use, the discovery of novel bactericidal compounds is essential before the development of resistance to the antimicrobials currently in use becomes widespread. Here, we explored the antimicrobial potential of two newly synthesized antimicrobials complexes and one natural compound against X. fastidiosa. Several nuclear magnetic resonance (NMR) assays with high resolution and sensitivity were developed to identify new diastereoisomers in the context of octahedral ruthenium - [Ru(narin)(phen)2]PF6-and magnesium naringenin 5-alkoxide - [Mg(narin)(phen)2]OAc - complexes, obtained in the present work. The NMR assays proved to be powerful tools for the identification of isomers in metal complexes. Moreover, a protocol for the in-vivo determination of the effects of these complexes against X. fastidiosa was developed. The main trunks of X. fastidiosa infected plants were injected with the two complexes as well as with the limonoid azadirachtin using a syringe; the number of bacterial cells in the plants following treatment was estimated via real-time quantitative PCR (qPCR). Importantly, the administration of both complexes and of azadirachtin drastically reduced the number of X. fastidiosa cells in vivo.

In this paper, a series of new ruthenium complexes of the general formula [Ru(NS)(dpphpy)(dppb)]PF6 (Ru1-Ru3), where dpphpy = diphenyl-2-pyridylphosphine, NS ligands = 2-thiazoline-2-thiol (tzdt, Ru1), 2-mercaptopyrimidine (pySm, Ru2), and 4,6-diamino-2-mercaptopyrimidine (damp, Ru3), and dppb = 1,4-bis(diphenylphosphino)butane, were synthesized and characterized by elemental analysis, spectroscopic techniques (IR, UV/visible, and 1D and 2D NMR), and X-ray diffraction. In the characterization, the correlation between the phosphorus atoms and their respective aromatic hydrogen atoms of the compounds in the assignment stands outs, by 1H-31P HMBC experiments. The compounds show anticancer activities against A549 (lung) and MDA-MB-231 (breast) cancer cell lines, higher than the clinical drug cisplatin. All of the complexes are more cytotoxic against the cancer cell lines than against the MRC-5 (lung) and MCF-10A (breast) nontumorigenic human cell lines. For A549 tumor cells, cell cycle analysis upon treatment with Ru2 showed that it inhibits the mitotic phase because arrest was observed in the Sub-G1 phase. Additionally, the compound induces cell death by an apoptotic pathway in a dose-dependent manner, according to annexin V-PE assay. The multitargeted character of the compounds was investigated, and the biomolecules were DNA, topoisomerase IB, and proteasome, as well as the fundamental biomolecule in the pharmacokinetics of drugs, human serum albumin. The experimental results indicate that the complexes do not target DNA in the cells. At low concentrations, the compounds showed the ability to partially inhibit the catalytic activity of topoisomerase IB in the process of relaxation of the DNA plasmid. Among the complexes assayed in cultured cells, complex Ru3 was able to diminish the proteasomal chymotrypsin-like activity to a greater extent.

International audience; Enterococci are gram-positive, widespread nosocomial pathogens that in recent years have developed resistance to various commonly employed antibiotics. Since finding new infection-control agents based on secondary metabolites from organisms has proved successful for decades, natural products are potentially useful sources of compounds with activity against enterococci. Herein are reported the results of a natural product library screening based on a whole-cell assay against a gram-positive model organism, which led to the isolation of a series of anacardic acids identified by analysis of their spectroscopic data and by chemical derivatizations. Merulinic acid C was identified as the most active anacardic acid derivative obtained against antibiotic-resistant enterococci. Fluorescence microscopy analyses showed that merulinic acid C targets the bacterial membrane without affecting the peptidoglycan and causes rapid cellular ATP leakage from cells. Merulinic acid C was shown to be synergistic with gentamicin against Enterococcus faecium, indicating that this compound could inspire the development of new antibiotic combinations effective against drug-resistant pathogens.

Candida glabrata, the most common non-albicans Candida species and one of the primary causes of candidemia, exhibits decreased susceptibility to azoles and more recently to echinocandins. Polyalthic acid 1, a furan diterpene, has been shown promising biological potential and in this study ent-polyalthic acid derivatives with antifungal activity against Candida glabrata were produced by microbial transformation. Incubation of 1 with Aspergillus brasiliensis afforded two known (compounds 5 and 10) and eight new derivatives (compounds 2–4, 6–9 and 11). The most common reaction was hydroxylation, but isomerization of the double bond and acetylation were also detected. None of the tested compounds showed cytotoxicity against HeLa, MCF-7 and MCF-10A cell lines showing IC50 values ranging from 62.6 µM to > 500 µM. Compounds 1, 5, 6, 8 and 11 showed fungistatic effects (ranging from 34.1 µM to 39.5 µM) on C. glabrata at lower concentrations than fluconazole (163.2 µM). Compounds 1, 6 and 8 were more potent fungicides (ranging from 79.0 to 143.6 µM) than fluconazole, which showed fungicidal effect at concentrations higher than 163.2 µM. These results suggest that ent-polyalthic acid and some of its derivatives could be used as lead compounds to develop new antifungal agents.

Made available in DSpace on 2020-12-10T19:48:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) A new method of screening was developed to generate 770 organic and water-soluble fractions from extracts of nine species of marine sponges, from the growth media of 18 species of marine-derived fungi, and from the growth media of 13 species of endophytic fungi. The screening results indicated that water-soluble fractions displayed significant bioactivity in cytotoxic, antibiotic, anti-Leishmania, anti-Trypanosoma cruzi, and inhibition of proteasome assays. Purification of water-soluble fractions from the growth medium of Penicillium solitum IS1-A provided the new glutamic acid derivatives solitumine A (1), solitumine B (2), and solitumidines A-D (3-6). The structures of compounds 1-6 have been established by analysis of spectroscopic data, chemical derivatizations, and vibrational circular dichroism calculations. Although no biological activity could be observed for compounds 1-6, the new structures reported for 1-6 indicate that the investigation of water-soluble natural products represents a relevant strategy in finding new secondary metabolites. Univ Sao Paulo, Inst Quim Sao Carlos, CP 780, BR-13560970 Sao Carlos, SP, Brazil Univ Fed Sao Carlos, Dept Quim, BR-13565905 Sao Carlos, SP, Brazil Univ Estadual Paulista, Inst Biociencias, Dept Bioquim & Microbiol, Campus Rio Claro,Avenida 24-A,1515, Rio Claro, SP, Brazil Univ Fed Sao Paulo, Inst Ciencia & Tecnol, BR-12231280 Sao Jose Dos Campos, SP, Brazil Univ Franca, Nucleo Pesquisa Ciencia & Tecnol, Ave Dr Armando Salles Oliveira,201 Pq Univ, BR-14404600 Franca, SP, Brazil Univ Sao Paulo, Dept Ciencias Exatas, Escola Super Agr Luiz de Queiroz, Agron, Ave Padua Dias 11,CP 9, BR-13418900 Piracicaba, SP, Brazil Natl Ctr Res Energy & Mat, Brazilian Biosci Natl Lab, Giuseppe Maximo Scolfaro 10000, BR-13083970 Campinas, SP, Brazil Univ Estadual Campinas, Inst Biol, BR-13083862 Campinas, SP, Brazil Univ Estadual Paulista, Inst Biociencias, Dept Bioquim & Microbiol, Campus Rio Claro,Avenida 24-A,1515, Rio Claro, SP, Brazil FAPESP: 2013/50228-8 FAPESP: 2016/21341-9 FAPESP: 2017/06014-4 FAPESP: 2013/23153-7 FAPESP: 2016/16033-3

Acmella oleracea (jambu) is a South American plant whose pharmacological properties include antimalarial, anesthetic, and anti-inflammatory activities. However, the compounds contributing to the anti-inflammatory effect have received little attention. In this study, the active compound spilanthol was isolated using a Green Chemistry approach and presented significant anti-inflammatory activity in a lipopolysaccharide-activated human neutrophil model. First, the aerial parts of jambu were extracted and fractionated using supercritical carbon dioxide. The spilanthol-enriched fractions obtained were then subjected to further purification by flash chromatography, yielding spilanthol with 97% purity. Use of enzyme-linked immunosorbent assay (ELISA) revealed a reduction in the release of Interleukin-8 and Tumor Necrosis Factor - alpha by leukocytes exposed to spilanthol. In conclusion, this new approach enabled spilanthol to be obtained at high purity, in a fairly rapid procedure, while the results of the in vitro anti-inflammatory activity study indicated that the compound could be a promising new therapeutic agent.

The electrochemical reduction of pendimethalin was studied by controlled potential electrolysis, employing the mercury pool electrode, in Na2SO4 0.1 mol L−1 pH = 8.0, with a constant potential of −1.0 V vs Ag/AgCl. The analysis of the products obtained was carried out by nuclear magnetic resonance (NMR), reaching a possible mechanism of reduction for this pesticide, proved by means of chemical quantum calculations. In such a mechanism, there was the reduction of the two nitro groups to hydroxylamine, involving 6 electrons, followed by the reduction of only one nitro group to amine, involving two more electrons. A structural rearrangement of the –NHCH(CH2CH3)2 cluster to a –CH2CH3 in the pesticide molecule was verified.

The industrial procesing of wood generates large amounts of residues that should be adequately managed. We identify methods to gain value wood rejects through phytochemical studies in three species of Fabaceae. Eight isoflavonoids were identified: 3′-hydroxy-7,8,4′,5′-tetramethoxypterocarpan from Swartzia laevicarpa; 8-O-methylretusin, cladrastin, 7,3′-dihydroxy-8,4′-dimethoxyisoflavone, and novel 7,3′-dihydroxy-5,6,4′trimethoxyisoflavone from Dipteryx odorata. In residues from Andira parviflora were identified genistein, biochanin A and 7,5′,6′-trihydroxy-4′-methoxyisoflavan. These compounds explain the natural resistance of these three timber species to xylophogous fungi.

Chemical investigation of the aqueous fraction of the ethanol extract from the Brazilian endemic marine sponge Clathria (Clathria) nicoleae Vieira de Barros, Santos & Pinheiro, 2013, Microcionidae, sampled from a 55 m deep rhodolith bed at the Amazon River mouth, led to the isolation of a new hexapeptide, clathriamide (1). HP-20 resin was used to capture compound 1 from the aqueous fraction, which was purified by additional chromatographic steps. The absolute configuration of the amino acids of 1 was determined by advanced Marfey’s analysis using 5-fluoro-2,4-dinitrophenyl-Nα-l-tryptophanamide. The amino acid derivatives analyzed by ultra-performance liquid chromatography coupled to a mass spectrometry using a C8 column enabled a good chromatographic resolution of l-Ile and l-allo-Ile, previously unfeasible using C18 column. Keywords: Porifera, Peptide, Advanced marfey’s analysis, Rhodolith bed, Aqueous extract

Studies of secondary metabolites (natural products) that cover their isolation, chemical synthesis and bioactivity investigation present myriad opportunities for discovery. For example, the isolation of novel secondary metabolites can inspire advances in chemical synthesis strategies to achieve their practical preparation for biological evaluation. In the process, chemical synthesis can also provide unambiguous structural characterization of the natural products. Although the isolation, chemical synthesis and bioactivity studies of natural products are mutually beneficial, they are often conducted independently. Here, we demonstrate the benefits of a collaborative study of the phomactins, diterpenoid fungal metabolites that serve as antagonists of the platelet activating factor receptor. Our isolation of novel phomactins has spurred the development of a bioinspired, unified approach that achieves the total syntheses of six congeners. We also demonstrate in vitro the beneficial effects of several phomactins in suppressing the rate of repopulation of tumour cells following gamma radiation therapy.

Mushroom alkaloids are of a considerable interest as a consequence of their unique secondary metabolites. This work describes the isolation and identification of brotasic acid methyl ester (1) from the fruiting bodies of the mushroom Auricularia sp. After isolation using a series of chromatographic steps, compound 1 was identified by analysis of spectroscopic data and has a novel carbon skeleton. The structure of 1 is related to the structure of the histone deacetylase inhibitor SAHA.

The electrochemical detection and electrooxidation path of the first-generation antihistamine receptor hydroxyzine (HDZ) and its main metabolite cetirizine (CTZ) are addressed in this research. A carbon black-modified electrode to explore the electrochemical responsivity and electroanalytical detection of HDZ and CTZ was designed. Compared to the bare electrode, the irreversible anodic responses observed for HDZ and CTZ were considerably improved on the proposed carbon black-modified electrode, including twenty times enhancement of the anodic peak currents and the shifting of anodic peak potentials to less positive potentials. In order to identify the electrooxidation products resulting from the previously verified irreversible redox processes, cyclic voltammetric studies and potentiostatic electrolysis assays followed by products identification by nuclear magnetic resonance (NMR) spectroscopy were carried out. From the combination of electrochemistry and NMR spectroscopy data it was possible to propose electrooxidation reaction mechanisms for HDZ and CTZ molecules. By applying square-wave adsorptive anodic stripping voltammetry (SWAdASV) under optimized experimental conditions, the obtained analytical curves for HDZ and CTZ were linear from 2.99 × 10 − 7 to 9.81 × 10 − 6 mol L − 1 and from 4.97 × 10 − 7 to 1.08 × 10 − 5 mol L − 1 , with limits of detection of 1.00 × 10 − 7 mol L − 1 and 4.00 × 10 − 7 mol L − 1 , respectively. Finally, spiked synthetic human biological fluids were analysed by the proposed SWAdASV procedures, with recovery percentages close to 100%.

Stevia rebaudiana is an important industrial crop due to the accumulation of high amounts of steviol glycosides (SG - natural sweeteners) in its leaves. S. rebaudiana cultivation has faced some pushbacks since this species is highly responsive to environmental factors, such as light availability. Sixty days after sowing, plants were transferred to different photoperiod conditions (12/12 h, 15/9 h, and 16/8 h of light/dark). Leaf extracts of plants growing at the 16/8 h photoperiod showed greater accumulation of antioxidant-like metabolites as compared to the other two photoperiods, which might be explained by the total phenolic content of the extracts. Additionally, plants growing at the 16/8 h photoperiod showed increased SOD activity as compared to plants growing at the 15/9 h photoperiod, which in turn showed higher SOD activity than plants growing at the 12/12 h photoperiod. It seems that SOD isoforms act synergically with phenolic compounds to prevent possible damages caused by reactive oxygen species that are produced in plants growing at long-day photoperiods. Sixteen metabolites were identified by Nuclear Magnetic Resonance in the leaf and stem extracts. Alanine, formate, choline, kaempferol-3-O-β- d -glucopyranoside-7-O-α- l -rhamnopyranoside, and gallic acid seems to contribute to maintain stevia homeostasis under unfavorable conditions. Furthermore, the accumulation of SGs and other bioactive compounds in S. rebaudiana in response to different photoperiods provides important leads for the improvement of its large-scale cultivation, as well as for the extraction and purification of phytochemicals with industrial interest.

Phytochemical investigation of the leaves of Guarea convergens T. D. Penn. led to the isolation of new apotirucallane triterpenes 24-acetoxy-25-hydroxy-3,7-dioxoapotirucalla-14-en-21,23-olide and 7α,24,25-trihydroxy-3-oxoapotirucalla-14-en-21,23-olide, steroid ergosta-5,24(24′)-diene-3β,7α,21-triol, in addition to the known ergosta-5,24(24′)-diene-3β,4β,22S-triol. The investigation from branches yielded the tirucallane triterpenes melianone and melianodiol. This is the first chemical study of this species, whose identified molecules contribute to knowledge of the biodiversity of the Amazonian forestan for chemosystematics of the Rutales order.

Marine sponges are a rich source of terpenoids with rearranged spongian carbon skeletons. Investigation of extracts from the sponge Darwinella cf. oxeata yielded four new rearranged diterpenoids, oxeatine (2) and oxeatamides H-J (3-5), as well as the known metabolites oxeatamide A (6), oxeatamide A methyl ester (7), and membranolide (1). Oxeatine (2) has a new heterocyclic skeleton, while oxeatamide J (5) has an N-methyl urea group included in a γ-lactam moiety. UPLC-QTOF analysis of the extract obtained from the mantle of the nudibranch Felimida grahami indicated the presence of 1 and 4.

α-Bisabolol is a natural terpene produced by Eremanthus erythropappus and is widely used in cosmetics and pharmaceuticals due to its anti-inflammatory, antibacterial and antimycotic properties. Due to these applications, a control of composition and authenticity of commercial oils rich in this terpene is required, resulting in a demand for new methodologies for quality control. In this work a rapid and efficient method for quantification of α-bisabolol in the essential oil of E. erythropappus (candeia) using 1H NMR was developed, validated and compared to gas chromatography (GC) method. The quantification of α-bisabolol by 1H NMR was successfully achieved for most of the essential oil samples of E. erythropappus evaluated, except for those with a more complex composition. To circumvent this limitation a 2D NMR COSY contour map was used. This method proved to be a fast and efficient alternative, providing results with standard deviations SD

Lawsone itself exhibits interesting biological activities, and its complexation with a metal center can improve the potency. In this context a cytotoxic Ru-complex, [Ru(law)(dppb)(bipy)] (law = lawsone, dppb = 1,4-bis(diphenylphosphino)butane and bipy = 2,2′-bipyridine), named as CBLAU, was prepared as reported. In this work, NMR binding-target studies were performed to bring to light the most accessible interaction sites of this Ru-complex toward Calf-Thymus DNA (CT-DNA, used as a model), in a similar approach used for other metallic complexes with anti-cancer activity, such as cisplatin and carboplatin. Advanced and robust NMR binding-target studies, among them Saturation Transfer Difference (STD)-NMR and longitudinal relaxometry (T1), were explored. The 1H and 31P -NMR data indicate that the structure of Ru-complex remains preserved in the presence of CT-DNA, and some linewidth broadening is also observed for all the signals, pointing out some interaction. Looking at the binding efficiency, the T1 values are highly influenced by the formation of the CBLAU-DNA adduct, decreasing from 11.4 s (without DNA) to 1.4 s (with DNA), where the difference is bigger for the lawsone protons. Besides, the STD-NMR titration experiments revealed a stronger interaction (KD = 5.9 mM) for CBLAU-DNA in comparison to non-complexed lawsone-DNA (KD = 34.0 mM). The epitope map, obtained by STD-NMR, shows that aromatic protons from the complexed lawsone exhibits higher saturation transfer, in comparison to other Ru-ligands (DPPB and bipy), suggesting the supramolecular contact with CT-DNA takes place by the lawsone face of the Ru-complex, possibly by a spatial π-π stacking involving π-bonds on nucleic acids segments of the DNA chain and the naphthoquinone group.

Actinobacteria are known by their ability to produce several antimicrobial compounds of biotechnological interest. Thus, in this study, we isolated and identified by partial 16S RNA sequencing ∼100 actinobacteria isolates from guarana (Paullinia cupana) bulk soil. Besides, we isolated from the actinobacteria Streptomyces morookaense AM25 a novel cyclic peptide, named gloeosporiocide, molecular formula C44H48N11O7S3 (calculated 938.2901), and characterized by the presence of cyclized cysteins to form three thiazols. The novel compound had activity against the plant pathogen Colletotrichum gloeosporioides, assayed by the paper disk diffusion method (42.7% inhibition, 0.1 mg disk−1) and by the microdilution assay (1.25 g L−1). Our results reveal the potential of the actinobacteria from the Amazon rhizospheric soils as biocontrol agents as well as producers of new compounds with antifungal activity. Thus, this work constitutes a step forward in the development of the biotechnology of actinobacteria in the production of compounds of agronomic interest.

In this paper, four new ruthenium complexes, [Ru(N-S)(dppm)2]PF6 (1), [Ru(N-S)(dppe)2]PF6 (2), [Ru(N-S)2(dppp)] (3) and [Ru(N-S)2(PPh3)2] (4) [dppm = 1,1-bis(diphenylphosphino)methane, dppe = 1,2-bis(diphenylphosphino)ethane, dppp = 1,3-bis(diphenylphosphino)propane, PPh3 = triphenylphosphine and N-S = 2-mercaptopyrimidine anion] were synthesized and characterized using spectroscopy techniques, molar conductance, elemental analysis, electrochemical techniques and X-ray diffraction. The DNA binding studies were investigated using voltammetry and spectroscopy techniques. The results show that all complexes exhibit a weak interaction with DNA. HSA interaction with the complexes was studied using fluorescence emission spectroscopy, where the results indicate a spontaneous interaction between the species by a static quenching mechanism. The cytotoxicity of the complexes was evaluated against A549, MDA-MB-231 and HaCat cells by MTT assay. Complexes (1) and (2), which are very active against triple negative MDA-MB-231, were subjected to further biological tests with this cell line. The cytotoxic activity triggered by the complexes was confirmed by clonogenic assay. Cell cycle analyses demonstrated marked anti-proliferative effects, especially at the G0/G1 and S phases. The morphological detection of apoptosis and necrosis - HO/PI and Annexin V-FITC/PI assay, elucidated that the type of cell death triggered by these complexes was probably by apoptosis. The in vivo toxicological assessment performed on zebrafish embryos revealed that complexes (1) and (2) did not present embryotoxic or toxic effects during embryonic and larval development showing that they are promising new prototypes of safer and more effective drugs for triple negative breast cancer treatment.

Made available in DSpace on 2019-10-04T12:31:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-10-01. Added 1 bitstream(s) on 2021-07-15T15:22:57Z : No. of bitstreams: 1 S1517-83822018000400840.pdf: 1193433 bytes, checksum: 4021607d35f01d91b6816b9a44e1d4ca (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Anthracnose is a crop disease usually caused by fungi in the genus Colletotrichum or Gloeosporium. These are considered one of the main pathogens, causing significant economic losses, such as in peppers and guarana. The current forms of control include the use of resistant cultivars, sanitary pruning and fungicides. However, even with the use of some methods of controlling these cultures, the crops are not free of anthracnose. Additionally, excessive application of fungicides increases the resistance of pathogens to agrochemicals and cause harm to human health and the environment. In order to find natural antifungal agents against guarana anthracnose, endophytic fungi were isolated from Amazon guarana. The compounds piliformic acid and cytochalasin D were isolated by chromatographic techniques from two Xylaria spp., guided by assays with Colletotrichum gloeosporioides. The isolated compounds were identified by spectrometric techniques, as NMR and mass spectrometry. This is the first report that piliformic acid and cytochalasin D have antifungal activity against C. gloeosporioides with MIC 2.92 and 2.46 mu mol mL(-1) respectively. Captan and difenocona-zole were included as positive controls (MIC 16.63 and 0.02 mu mol mL(-1), respectively). Thus, Xylaria species presented a biotechnological potential and production of different active compounds which might be promising against anthracnose disease. (C) 2018 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. Univ Sao Paulo, Dept Ciencias Exatas, Escola Super Agr Luiz de Queiroz, Piracicaba, SP, Brazil Univ Sao Paulo, Dept Genet, Escola Super Agr Luiz de Queiroz, Piracicaba, SP, Brazil Univ Estadual Paulista, Inst Biociencias, Dept Bioquim & Microbiol, Rio Claro, SP, Brazil Univ Fed Sao Carlos, Dept Quim, Sao Carlos, SP, Brazil Univ Estadual Paulista, Inst Biociencias, Dept Bioquim & Microbiol, Rio Claro, SP, Brazil FAPESP: 2014/15760-3 FAPESP: 2013/50228-8 CNPq: 142079/2016-2 : FAPESP: 2012/02000-5 : FAPESP: 2014/05940-4

Two new polyketide phosphate monoesters, phosdiecin A (1) and phosdiecin B (2), were isolated from a culture of the marine Streptomyces sp. SS99BA-2 using the hyphenated technology LC-SPE/NMR. The compounds showed to be new representatives of an important class of antitumor and antibiotic metabolites known as fostriecins. Their structures, including relative configuration attribution, were fully elucidated through extensive analyses of NMR and MALDI-TOF/TOF HR-MS data. Herein, the application of this system to isolate and identify the new compounds is described.

Sensitive, simple, low-cost, and rapid amperometric flow-injection methods were developed for determination of ivermectin (IVM) and levamisole (LVM) in anthelmintic pharmaceutical drugs and urine samples. These determinations were carried out with a cathodically (for IVM) or anodically (for LVM) pretreated boron-doped diamond electrode using aqueous 0.5 mol L −1 H 2 SO 4 (with and without addition of 30% V / V of ethanol) as supporting electrolyte. The amperometric detection was performed at an applied electrode potential of E = 1.40 V, for IVM, and E = 1.90 V, for LVM, vs. Ag/AgCl (3.0 mol L −1 KCl). The respective analytical curves presented good linearity in the investigated concentration ranges (0.60–50 μmol L −1 , for IVM, and 0.010–5.0 μmol L −1 , for LVM) and the detection limits were 0.30 μmol L −1 for IVM, and 1 nmol L −1 , for LVM. Investigation of possible interferents showed no significant interference with the here-proposed methods; thus, they were used to determine IVM and LVM in pharmaceutical formulations as well as in urine samples, with results that showed good agreement with comparative methods. Furthermore, a mechanism for LVM electrooxidation was proposed using exhaustive potentiostatic electrolysis and NMR measurements.

Propolis is a resin produced by bees from raw material collected from plants, salivary secretions, and beeswax. New therapeutic properties for the Central Nervous System have emerged. We explored the neurobehavioral and antioxidant effects of an ethanolic extract of yellow propolis (EEYP) rich in triterpenoids, primarily lupeol andβ-amyrin. Male Wistar rats, 3 months old, were intraperitoneally treated with Tween 5% (control), EEYP (1, 3, 10, and 30 mg/kg), or diazepam, fluoxetine, and caffeine (positive controls) 30 min before the assays. Animals were submitted to open field, elevated plus maze, forced swimming, and inhibitory avoidance tests. After behavioral tasks, blood samples were collected through intracardiac pathway, to evaluate the oxidative balance. The results obtained in the open field and in the elevated plus maze assay showed spontaneous locomotion preserved and anxiolytic-like activity. In the forced swimming test, EEYP demonstrated antidepressant-like activity. In the inhibitory avoidance test, EEYP showed mnemonic activity at 30 mg/kg. In the evaluation of oxidative biochemistry, the extract reduced the production of nitric oxide and malondialdehyde without changing level of total antioxidant, catalase, and superoxide dismutase, induced by behavioral stress. Our results highlight that EEYP emerges as a promising anxiolytic, antidepressant, mnemonic, and antioxidant natural product.

Isocorilagin, the α-anomer of the ellagitannin corilagin, has been frequently reported in the literature as a constituent of various plant species. Its identification is based mainly on the smaller value for the coupling constant of its anomeric proton when compared to that of corilagin. A careful investigation of the corilagin structure in both methanol and DMSO solutions using NMR, electronic and vibrational CD, and DFT and MD calculations confirmed that isocorilagin is the result of a solvent-induced conformational transition of corilagin, rather than its diastereoisomer. Corilagin changes from B1,4 and (o)S5 conformations of the β-glucose core in DMSO-d6 to an inverted (1)C4 conformation in methanol-d4, which accounts for NMR observables attributed to the alleged α-anomer. This misassignment reinforces the risks of relying upon a single technique for structural elucidation and stereochemical analysis of complex natural products, especially those containing saccharide moieties.

The synthesis and spectroscopic characterization of nine π-arene piano-stool ruthenium (II) complexes with aromatic dinitrogen chelating ligands or containing chloroquine (CQ), are described in this study: [Ru(η(6)-C10H14)(phen)Cl]PF6 (1), [Ru(η(6)-C10H14)(dphphen)Cl]PF6 (2), [Ru(η(6)-C10H14)(bipy)Cl]PF6 (3), [Ru(η(6)-C10H14)(dmebipy)Cl]PF6 (4) and [Ru(η(6)-C10H14)(bdutbipy)Cl]PF6 (5), [Ru(η(6)-C10H14)(phen)CQ](PF6)2 (6), [Ru(η(6)-C10H14)(dphphen)CQ](PF6)2 (7), [Ru(η(6)-C10H14)(bipy)CQ](PF6)2 (8), [Ru(η(6)-C10H14)(dmebipy)CQ](PF6)2 (9): [1,10-phenanthroline (phen), 4,7-diphenyl-1,10-phenanthroline (dphphen), 2,2'-bipyridine (bipy), 5,5'-dimethyl-2,2'-bipyridine (dmebipy), and 4,4'-di-t-butyl-2,2'-bipyridine (dbutbipy)]. The solid state structures of five ruthenium complexes (1-5) were determined by X-ray crystallography. Electrochemical experiments were performed by cyclic voltammetry to estimate the redox potential of the Ru(II)/Ru(III) couple in each case. Their interactions with DNA and BSA, and activity against four cell lines (L929, A549, MDA-MB-231 and MCF-7) were evaluated. Compounds 2, 6 through 9, interact with DNA which was comparable to the one observed for free chloroquine. The results of fluorescence titration revealed that these complexes strongly quenched the intrinsic fluorescence of BSA following a static quenching procedure. Binding constants (Kb) and the number of binding sites (n~1) were calculated using modified Stern-Volmer equations. The thermodynamic parameters ΔG at different temperatures were calculated and subsequently the values of ΔH and ΔS were also calculated, which revealed that hydrophobic and electrostatic interactions play a major role in the BSA-complex association. The MTT assay results indicated that complexes 2, 5 and 7 showed cytostatic effects at appreciably lower concentrations than those needed for cisplatin, chloroquine and doxorubicin.

This study investigated the chronic effect of inspiratory muscle training (IMT) on the human serum metabolome in healthy male recreational cyclists. Using a randomized, parallel group design, twenty-eight participants were randomized to three IMT groups: low intensity (LI, n = 7), moderate intensity (MI, n = 10), and high intensity (HI, n = 11). The IMT was performed for 11 weeks. Another group of participants under the same conditions, who did not perform the IMT but participated in all procedures, was included as controls (CG, n = 6). Blood samples were collected one week before and after 11 weeks of IMT and analyzed for metabolite shifts using 1H NMR. Statistical analysis included a 4 (group) &times, 2 (time) repeated measures ANOVA using the general linear model (GLM), and multivariate principal component analysis (PCA). Untargeted metabolomics analysis of serum samples identified 22 metabolites, including amino acids, lipids, and tricarboxylic acid cycle intermediates. Metabolites shifts did not differ between groups, indicating that IMT at three intensity levels did not alter the serum metabolome relative to the control group. These results reveal novel insights into the metabolic effects of the IMT and are consistent with the results from other studies showing negligible chronic alterations in the serum metabolome in response to physical training.

The metabolite profiling associated with the antioxidant potential of Amazonian fruits represents an important step to the bioactive compound&prime, s characterization due to the large biodiversity in this region. The comprehensive bioactive compounds profile and antioxidant capacities of mamey apple (Mammea americana), camapu (Physalis angulata), and uxi (Endopleura uchi) was determined for the first time. Bioactive compounds were characterized by ultra-performance liquid chromatography coupled to high resolution mass spectrometry (UPLC-MSE) in aqueous and ethanolic extracts. Globally, a total of 293 metabolites were tentatively identified in mamey apple, campau, and uxi extracts. The main classes of compounds in the three species were terpenoids (61), phenolic acids (58), and flavonoids (53). Ethanolic extracts of fruits showed higher antioxidant activity and total ion abundance of bioactive compounds than aqueous. Uxi had the highest values of phenolic content (701.84 mg GAE/100 g), ABTS (1602.7 &mu, mol Trolox g&minus, 1), and ORAC (15.04 &mu, 1). Mamey apple had the highest results for DPPH (1168.42 &mu, mol TE g&minus, 1) and FRAP (1381.13 &mu, mol FSE g&minus, 1). Nuclear magnetic resonance (NMR) spectroscopy results showed that sugars and lipids were the substances with the highest amounts in mamey apple and camapu. Data referring to chemical characteristics and antioxidant capacity of these fruits can contribute to their economic exploitation.

The new pyrrole-imidazole and pyrrole-guanidine alkaloids 4-debromooroidin (1), 4-debromougibohlin (2), 5-debromougibohlin (3), and 5-bromopalau'amine (4), along with the known hymenidin (5) and (+)-monobromoisophakellin (6), have been isolated from a Dictyonella sp. marine sponge, collected at the Amazon River mouth. The bromine-substitution pattern observed for compounds 1, 2 and 4 is unusual among bromopyrrole alkaloids isolated from marine sponges. The 20S proteasome inhibitory activities of compounds 1-6 have been recorded, with 5-bromopalau'amine (4) being the most active in this series.

Orange peel is a by-product produced in large amounts that acts as a source of natural pigments such as carotenoids. Xanthophylls, the main carotenoid class found in citrus fruit, can be present in its free form or esterified with fatty acids, forming esters. This esterification modifies the compound&rsquo, s chemical properties, affecting their bioavailability in the human body, and making it important to characterize the native carotenoid composition of food matrices. We aimed to evaluate the non-saponified carotenoid extracts of orange peel (cv. Pera) obtained using alternative green approaches: extraction with ionic liquid (IL), analyzed by high performance liquid chromatography coupled to a diode array detector with atmospheric pressure chemical ionization and mass spectrometry HPLC-DAD-APCI-MS, and supercritical fluid extraction (SFE), followed by supercritical fluid chromatography with atmospheric pressure chemical ionization and triple quadrupole mass spectrometry detection (SFC-APCI/QqQ/MS) in an online system. Both alternative green methods were successfully applied, allowing the total identification of five free carotenoids, one apocarotenoid, seven monoesters, and 11 diesters in the extract obtained with IL and analyzed by HPLC-DAD-APCI-MS, and nine free carotenoids, six carotenoids esters, 19 apocarotenoids, and eight apo-esters with the SFE-SFC-APCI/QqQ/MS approach, including several free apocarotenoids and apocarotenoid esters identified for the first time in oranges, and particularly in the Pera variety, which could be used as a fruit authenticity parameter.

Alzheimer’s disease (AD) is one of the most common forms of dementia and a significant threat to the elderly populations, especially in the Western world. The rapid hydrolysis of the principal neurotransmitter into choline and acetate by acetylcholinesterase (AChE) at synapses causes the loss of cognitive response that becomes the real cause of AD. Therefore, inhibition of AChE is the most fundamental therapy among currently available treatments for AD. In this context, we designed and performed molecular recognitions studies of coumarin-based inhibitors towards AChE. STD NMR and Tr-NOESY applications were utilized to evaluate the binding epitope, the dissociation constant (KD) and bound conformations of these inhibitors within this inhibitor-AChE complex. Compound 1, which has a similar inhibition activity to tacrine (a current drug) led in this study as a stronger binder with KD = 30 μM ,even greater than tacrine (KD = 140 μM). Moreover, docking simulations mimic NMR results and provided evidence of synchronizing binding of compound 1 with three sites; the peripheral anionic site, the bottom of the gorge, and the catalytic site. Therefore, we envisioned from our experimental and theoretical results that coumarin-based inhibitors containing a piperidinyl scaffold might be a potential drug candidates for AD in the future.