Search

The gastroprotective effects of Jacaranda puberula Cham., Bignoniaceae, a tree native to the Brazilian Atlantic Forest, were evaluated using two models of acute ulceration in mice: acidified ethanol- and non-steroidal anti-inflammatory-induced ulceration. The mice were divided into five groups and treated orally with vehicle, carbenoxolone, or hydroalcoholic extract obtained from the tested plant (3, 30, or 300 mg/kg). Results showed that the doses of 300 mg/kg decreased both acidified ethanol- and indomethacin-induced ulceration by 89% and 33%, respectively, compared to the vehicle (p

The harmful impact caused by pesticides on human health and the environment necessitates the development of efficient degradation processes and control of prohibited stocks of such substances. Organophosphates (OPs) are among the most used agrochemicals in the world and their degradation can proceed through several possible pathways. Investigating the reactivity of OPs with nucleophilic species allows one to propose new and efficient catalyst scaffolds for use in detoxification. In light of the remarkable catalytic activity of imidazole (IMZ) at promoting dephosphorylation processes of OPs, the reactivity of 4(5)-hydroxymethylimidazole (HMZ) with diethyl-2,4-dinitrophenylphosphate (DEDNPP) and Paraoxon are evaluated by combining experimental and theoretical approaches. It is observed that HMZ is an efficient and regiospecific catalyst with reactivity modulated by competing tautomers. To propose an optimal IMZ-based catalyst, quantum chemical calculations were performed for monosubstituted 4(5)IMZ derivatives that might cleave DEDNPP. Both inductive effects and hydrogen bonding by the substituents are shown to influence barriers and mechanisms.

Inspired by the synthetic and biological potential of organotellurium substances, a series of five- and six-membered ring organotelluranes containing a Te-O bond were synthesized and characterized. Theoretical calculations elucidated the mechanism for the oxidation-cyclization processes involved in the formation of the heterocycles, consistent with chlorine transfer to hydroxy telluride, followed by a cyclization step with simultaneous formation of the new Te-O bond and deprotonation of the OH group. Moreover, theoretical calculations also indicated anti-diastereoisomers to be major products for two chirality center-containing compounds. Antileishmanial assays against Leishmania amazonensis promastigotes disclosed 1,2λ4 -oxatellurane LQ50 (IC50 =4.1±1.0; SI=12), 1,2λ4 -oxatellurolane LQ04 (IC50 =7.0±1.3; SI=7) and 1,2λ4 -benzoxatellurole LQ56 (IC50 =5.7±0.3; SI=6) as more powerful and more selective compounds than the reference, being up to four times more active. A stability study supported by 125 Te NMR analyses showed that these heterocycles do not suffer structural modifications in aqueous-organic media or at temperatures up to 65 °C.

The seed oil of Annona salzmannii A. DC. was analyzed by GC-MS and 1H qNMR, revealing a mixture of unsaturated (80.5%) and saturated (18.7%) fatty acids. Linoleic (45.3%) and oleic (33.5%) acid were the major unsaturated fatty acids identified, while palmitic acid (14.3%) was the major saturated fatty acid. The larvicidal effects of A. salzmannii seed oil were evaluated against third-instar larvae of Aedes aegypti (Linn.). The oil exhibited moderate larvicidal activity, with a LC50 of 569.77 ppm (95% CI = 408.11 to 825.88 ppm). However, when the cytotoxic effects of the oil were evaluated, no expressive antiproliferative effects were observed in tumor cell lines B16-F10 (mouse melanoma), HepG2 (human hepatocellular carcinoma), K562 (human chronic myelocytic leukemia), HL-60 (human promyelocytic leukemia), and non-tumor cell line PBMC (peripheral blood mononuclear cells), with IC50 values > 50 μg·mL-1. This is the first study to evaluate the chemical composition, larvicidal and cytotoxic activity of A. salzmannii seed oil.

The sequential electrodeposition of Pt nanoparticles and CeO2 protective layers has been explored as a simple method to prepare structured catalytic reactors characterized by a core–shell metal-metal oxide active phase directly anchored onto metallic (Fecralloy) 3D open foam substrates. The application of a CeO2 overlayer onto preformed Pt nanoparticles promoted the intrinsic catalytic activity for CO oxidation and induced a remarkable stabilization effect against sintering and extensive reconstruction of the active phase up to 800 °C.

Carbon nanohorns and oxidised carbon nanohorns-based nanofluids were characterised by taking one step forward. The advantage of studying oxidised carbon nanohorns is that they are surfactant-free. The stability of both nanofluids was checked after a 3-month preparation period at high temperature, which comes closer to real applications. Two different dynamic light scattering (DLS) systems were used to measure stability at high temperature before being compared. A deep optical analysis was run. An integrating sphere was attached to the classic spectrophotometer to determine the scattering of nanofluids. After obtaining the experimental values of the optical parameters for both nanofluids, the Kubelka-Munk Theory was applied to obtain optical coefficients. Finally, the scattering albedo was calculated to facilitate comparisons with the literature. Studying both nanofluid types provided us with new knowledge about their potential use as direct solar absorbers in solar thermal collectors.

The interactions between ionic liquids and water are very important for the chemical industry. The advancement of research between levels of interactions and the presence of clustering can boost the pharmaceutical industry and of polymers. The aim of this work was to use different protic ionic liquids to observe the formation of aggregated using the NMR 1D NOESY. The results reveal the presence of Nuclear Overhauser Effect in some systems and the behavior of the NOE effect does not seem to be so linear, that is, the increase in the size of the alkyl chain lengths ranging does not guarantee the presence of supra molecular aggregates.

Transthyretin (TTR) is a tetrameric protein synthesized mostly by the liver. As a result of gene mutations or as an ageing-related phenomenon, TTR molecules may misfold and deposit in the heart and in other organs as amyloid fibrils. Cardiac involvement in TTR-related amyloidosis (ATTR) manifests typically as left ventricular pseudohypertrophy and/or heart failure with preserved ejection fraction. ATTR is an underdiagnosed disorder as well as a crucial determinant of morbidity and mortality, thus justifying the current quest for a safe and effective treatment. Therapies targeting cardiac damage and its direct consequences may yield limited benefit, mostly related to dyspnoea relief through diuretics. For many years, liver or combined heart and liver transplantation have been the only available treatments for patients with mutations causing ATTR, including those with cardiac involvement. The therapeutic options now include several pharmacological agents that inhibit hepatic synthesis of TTR, stabilize the tetramer, or disrupt fibrils. Following the positive results of a phase 3 trial on tafamidis, and preliminary findings on patisiran and inotersen in patients with ATTR-related neuropathy and cardiac involvement, we provide an update on this rapidly evolving field, together with practical recommendations on the management of cardiac involvement.

Phytochemical investigation of the atemoya aerial parts was carried out by LC-MS-IT and cytotoxic activities were evaluated as well. These results led to the identification of a new N-oxide alkaloid (dehydroanomuricine-N-oxide) and eight other alkaloids: scoulerine, reticuline, isocorydine, norisocorydine, asimilobine, nornuciferine, anonaine, and liriodenine. The new alkaloid dehydroanomuricine-N-oxide and anomuricine were also isolated. The structures of these compounds were determined by spectroscopic and spectrometric techniques. The cytotoxic capacity of crude methanolic extract and the alkaloidal fraction were evaluated, showing moderate cytotoxicity. The isolation and identification of these alkaloids are an important contribution to the chemotaxonomy of the genus Annona and the Annonaceae family.

Inflammation plays an important role in atherosclerosis. Acute coronary syndromes (ACS), and particularly myocardial infarction (MI), are associated with a systemic inflammatory response that may accelerate coronary atherosclerotic processes, leading to plaque destabilization and increased risk of further cardiovascular events. These considerations provide a conceptual framework for the use of anti-inflammatory therapies in patients with chronic coronary syndrome or ACS. Following the diverging results of trials on canakinumab and methotrexate, the Colchicine Cardiovascular Outcomes Trial (COLCOT) and the Low-Dose Colchicine trial-2 (LoDoCo2) have sparked new interest in the perspective of an anti-inflammatory therapy for CAD by showing that colchicine confers a prognostic benefit in patients with a recent MI or CCS, respectively. Colchicine blocks multiple steps of the inflammatory cascade and modulates also platelet function and endothelial activation. It has a better safety profile than canakinumab and is a very inexpensive drug throughout the world. We deemed it useful to reappraise the available literature on colchicine and coronary artery disease to assess the likelihood that it might become part of the therapeutic armamentarium of this condition.

Ceria was deposited onto boron doped polycrystalline diamond (BDD) cathodes, through electrochemically induced precipitation from nitrate-based solutions. The deposits were characterized using SEM-EDS, HRTEM, XRD and XPS. The morphology, thickness and composition of ceria films, which besides CeO2 contained Ce(OH)(3) when prepared at very negative potential, were controlled by tuning the deposition parameters. Thin Ce(OH)(3)-free ceria films allowed CO2 electrochemical reduction at overpotentials below 50 mV, yielding formic acid with faradaic yield higher than 40% and stable performance for many hours. Ceria seemed to act as a co-catalyst that activated CO2 for reduction at the H-terminated BDD surface, because comparable results were not obtained with ceria-coated glassy carbon electrodes.

Berberis laurina (Berberidaceae) is a well-known medicinal plant used in traditional medicine since ancient times, however, it is scarcely studied to a large-scale fingerprint. This work presents a broad-range fingerprints determination through high-resolution magical angle spinning (HR-MAS) nuclear magnetic resonance (NMR) spectroscopy, a well-established flexible analytical method and one of most powerful &ldquo, omics&rdquo, platforms. It had been intended to describe a large range of chemical compositions in all plant parts. Beyond that, HR-MAS NMR allowed the direct investigation of botanical material (leaves, stems, and roots) in their natural, unaltered states, preventing molecular changes. The study revealed 17 metabolites, including caffeic acid, and berberine, a remarkable alkaloid from the genus Berberis L. The metabolic pattern changes of the leaves in the course of time were found to be seasonally dependent, probably due to the variability of seasonal and environmental trends. This metabolites overview is of great importance in understanding plant (bio)chemistry and mediating plant survival and is influenceable by interacting environmental means. Moreover, the study will be helpful in medicinal purposes, health sciences, crop evaluations, and genetic and biotechnological research.

Oxidized carbon nanohorn water based nanofluids are attracting more and more attention for solar harvesting applications because of their peculiar features: stable suspension without any surfactant, higher solar absorbance values as compared to the base fluid, etc. However, these nanofluids are still matter of research because not all their properties have been comprehensively studied yet. This paper is focused on the wettability properties of the carbon nanohorn water based nanofluids on different metal surfaces. The static contact angle was measured for ten nanofluids with concentrations ranging from 0.002%wt to 0.1% wt, five of those used non-oxidized carbon nanohorns while the other five used oxidized carbon nanohorns. Moreover, this work investigates a novel use of the oxidized carbon nanohorn nanofluids to deposit an ultra-thin layer via pool boiling. The realized coating was proved to be stable and found to slightly affect the wettability of the nanofluids. Finally, the solar reflectance of the coated aluminum sample was measured and found to be from 2 to 10 times lower as compared to a reference aluminum surface.

Onychopetalum is an Amazonian botanical genus close-related with Bocageopsis and Unonopsis, whose species are used in traditional medicine. Although these genera are widely investigated from the phytochemical viewpoint, the knowledge about Onychopetalum remains almost unexplored. In order to perform a comprehensive characterization of isoquinoline-derived alkaloids from Onychopetalum amazonicum, an integrative approach based on the alkaloid profile analysis by leaf spray mass spectrometry (LS-MS), followed by a robust dereplication through high-performance liquid chromatography coupled with diode array detector and atmospheric pressure chemical ionization tandem mass spectrometry, (HPLC-DAD-APCI-MS/MS) and nuclear magnetic resonance (NMR) analysis was adopted. LS-MS allowed the tentative identification of reticuline, norjuziphine, nornuciferine, O-methylisopiline, nuciferine, N-methyl-O-methylisopiline, anonaine, and N-methylanonaine. HPLC-DAD-MS/MS analysis supported the tentative identification of N-methylasimilobine, asimilobine, norushinsunine, N-methylisopiline, isopiline, liriodenine, and lysicamine. Moreover, the integration of MS and NMR data allowed the additional identification of stepholidine and isocorypalmine. The applied integrative approach proposed herein enabled a comprehensive analysis of the alkaloid content from the O. amazonicum, showing to be a useful strategy for the dereplication of isoquinoline-derived alkaloids.

Nanolubricants, thanks to their ability to reduce friction and wear, are increasingly studied in the transport and automotive sectors. These systems are generally produced with a two-step procedure by dispersing nanoparticles into base oils. Very recently, one-step methods have received increasing attention for the production of highly stable nanosuspensions at lower cost. Degradation-decomposition of the base oil can however occur during the synthesis affecting the final performances. In this work, copper-based nanolubricants were produced using a new procedure that preserves the base oil from the degradation induced by the synthesis and allows producing highly stable nanolubricant. The produced fluid showed a monodisperse distribution of nanometric particles and a good stability up to at least 60 days from its production. The as-produced nanolubricants showed notable performance reducing the friction coefficient even up to 32.7% for Cu concentration of 0.01 vol% at 80°C.

Zika, dengue, and chikungunya are vector-borne diseases of pronounced concern transmitted by the mosquito Aedes aegypti Linn. (Diptera: Culicidae). The most important method to avoid outbreaks is to control mosquito spreading by the employment of insecticides and larvicides. Failure to control mosquito dispersal is mostly accounted to Ae. aegypti resistance to currently available larvicides and insecticides, encouraging the development of novel pesticides. In addition, the excessive use of larvicides poses serious threats to human health and the environment. Evaluation of natural products as larvicides in an attempt to overcome this situation is often found in the literature because products originated from nature are considered less toxic to non-target species and more eco-friendly. (-)-Borneol is a bicyclic monoterpene present in essential oils with moderate larvicidal activity. On account of these facts, it was of our interest to synthesize (-)-borneol ester derivatives aiming to study its structure-activity relationships against Ae. aegypti larvae. With the goal to estimate toxicity to a non-target species, evaluation of the lethal concentration 50% (LC50) on Artemia sp. (Artemiidae) and calculation of selectivity towards Ae. aegypti were carried out. The most potent derivative, (-)-Bornyl chloroacetate, exhibited the highest suitability index, demonstrating lower environmental toxicity than other borneol ester derivatives. A parabolic relationship between (-)-borneol esters larvicidal activity and partition coefficient (Log P) was achieved and a correlation equation obtained, validating the importance of lipophilicity to the larvicidal activity of these compounds.

Made available in DSpace on 2018-11-26T17:54:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Scientific Support and Development Program of the School of Pharmaceutical Sciences of UNESP (PADC/FCFAr, UNESP) There have been few studies on the pharmacological properties of Rhamnus sphaerosperma var. pubescens, a native Brazilian species popularly known as fruto-de-pombo. The aim of this study was to investigate the scavenging capacity of emodin, physcion, and the ethanolic crude extract of Rhamnus sphaerosperma var. pubescens against reactive oxygen and nitrogen species, as well as their role and plausible mechanisms in prompting cell death and changes in AKT phosphorylation after cervical (SiHa and C33A) and oral (HSC-3) squamous cell carcinoma treatments. Emodin was shown to be the best scavenger of NO center dot and O-2(center dot-), while all samples were equally effective in HOCl/OCl- capture. Emodin, physcion, and the ethanolic extract all exhibited cytotoxic effects on SiHa, C33A, HSC3, and HaCaT (immortalized human keratinocytes, nontumorigenic cell line), involving mixed cell death (apoptosis and necrosis) independent of the caspase activation pathway. Emodin, physcion, and the ethanolic extract increased intracellular oxidative stress and DNA damage. Emodin decreased the activation of AKT in all tumor cells, physcion in HSC3 and HaCaT cells, and the ethanolic extract in C33A and HaCaT cells, respectively. The induction of cancer cell death by emodin, physcion, and the ethanolic crude extract of Rhamnus sphaerosperma var. pubescens was related to an increase in intracellular oxidative stress and DNA damage and a decrease in AKT activation. These molecules are therefore emerging as interesting candidates for further study as novel options to treat cervical and oral carcinomas. Sao Paulo State Univ UNESP, Sch Pharmaceut Sci, Dept Clin Anal, BR-14800903 Araraquara, SP, Brazil Fed Univ Parana UFPR, Dept Pharm, BR-80210170 Curitiba, PR, Brazil Fed Univ Parana UFPR, Dept Chem, BR-80210170 Curitiba, PR, Brazil Sao Paulo State Univ UNESP, Sch Pharmaceut Sci, Dept Clin Anal, BR-14800903 Araraquara, SP, Brazil

1H NMR spectroscopy was used to characterize seventeen Brazilian plant oils from different botanical origins and to determine the total phenolic content, as well as the antioxidant and antimicrobial activity. A profiling approach based on NMR and PCA revealed that the phenolic compounds signals (tangeretin, nobiletin and demethylnobiletin), as well as limonene, play an important role in the discrimination of the edible oils of tangerine (conventional and organic). Ricinolenic acid was responsible for the grouping of castor oil and the distinguishing other oils that can be characterized by the presence of fatty acids. In addition, polyaltic acid and kaurenoic acid were detected in the copaiba oil but were not observed in the other oils. The organic tangerine oil showed the highest content of total phenolic compounds and the highest level of antioxidant activity in relation to DPPH and ABTS. Most of the tested oils showed antimicrobial activity in relation to S. Typhimurium and S. Enteritidis, in a way that the buriti and the golden flaxseed organic oils displayed the highest activity, respectively. However, S. aureus, L. monocytogenes, and B. cereus demonstrated resistance to most of the tested oils. These findings may help in the understanding of edible oils and also how to check their quality based on analytical and biological approaches.

In this work, powders of Single Wall Carbon Nanohorns (SWCNHs), a typical hydrophobic material, were oxidized with concentrated HNO3 with the aim of surface carboxylation and consequent improved hydrophilicity and dispersibility in polar solvents. Dynamic Light Scattering and zeta-potential measurements demonstrated that very stable colloidal suspensions of SWCNH in water were obtained in total absence of stabilizers. By properly optimizing the reaction parameters, the suspensions achieved stability even higher than colloids with similar composition but prepared with the use of surfactants. Surface damage and oxidation degree of SWCNHs were evaluated by SEM microscopy, Thermogravimetric Analysis, Residual Gas Analysis, XPS and UV-visible spectroscopy.

The biological activity of tellurium compounds is closely related to the tellurium oxidation state or some of their structural features. Hypervalent dihalogenated organotelluranes 1-[butyl(dichloro)-λ4-tellanyl]-2-(methoxymethyl)benzene (1a) and 1-[butyl(dibromide)-λ4-tellanyl]-2-(methoxymethyl)benzene (1b) have been described as inhibitors of proteases (cysteine and threonine) and tyrosine phosphatases. However, poor attention has been given to their physicochemical properties. Here, a detailed investigation of the stability in water of these organotelluranes is reported using 125Te NMR analysis. Dihalogenated organotelluranes 1a and 1b were both stable in DMSO-d6 (from 25 to 75 °C), demonstrating their thermal stability. However, the addition of a phosphate buffer solution (pH 2–8) to 1a or 1b resulted in an immediate conversion to a new Te species, assumed to be the corresponding telluroxide. Similar behavior was observed in pure water, demonstrating the low chemical stability of these dihalogenated sp...

1H HR-MAS NMR spectroscopy was used to track the metabolic changes throughout the whole development of astringent ('Giombo') and non-astringent ('Fuyu') cultivars of persimmon (Diospyros kaki). The NMR data revealed the low concentration of amino acids (threonine, alanine, citrulline and GABA) and organic acids (malic acid). In addition, the signals of carbohydrates (sucrose, glucose and fructose) seemed to play the most important role in the fruit development. In both cultivars, the growth was characterized by fluctuating sucrose concentration along with a constant increase in both glucose and fructose. In the initial growth stage, the polyphenol composition was quite different between the cultivars. Gallic acid was detected throughout the growth of 'Giombo', while for 'Fuyu', signals of polyphenols disappeared over time. Additional multivariate analysis suggested that these cultivars share many metabolic similarities during development. These findings might help the comprehension of fruit development, which in turn, impacts the quality of the fruits.

Lithium wall conditioning has improved the performance of many magnetic fusion devices. Li conditioning in the RFX-mod device was performed by: (1) a single Li pellet injector and (2) a multi-Li pellet injector during He plasma discharges; (3) a Li evaporator after He glow discharge cleaning and He plasma discharge exposure. This report compares the spatial and depth distributions of Li deposited on polycrystalline graphite witness samples at different locations in RFX-mod and the elemental and chemical compositions of the resulting surfaces. The sample surfaces were analyzed ex situ using secondary ion mass spectrometry (SIMS) and high-resolution X-ray photoelectron spectroscopy (HR-XPS). The results showed that Li pellet injection provided a relatively uniform toroidal coverage while Li evaporation produced highly localized Li deposition. A Li 1s HR-XPS peak at 56.5 eV binding energy (BE) characteristic of lithium-intercalated graphite was only observed with the sample exposed to Li evaporation. All of the samples exhibited a HR-XPS C 1s peak at 285.1–285.2 eV BE that is largely attributed to hydrogenated graphite. This finding suggests that hydrogenation of fresh graphite occurs during He plasma discharge exposures. Our results have implications for density control and the selection of Li conditioning techniques in magnetic fusion devices.

Phase change material nano-emulsions are investigated as potential working fluids for various applications including heat transfer and solar applications. Main hindrances to their application are the difficulty in maintaining emulsion stability and the subcooling effect. In this study, new phase change material nano-emulsions (PCMEs) were designed and characterized as possible heat transfer media to be used at 21 and 55 °C, by investigating two commercial phase change materials melting at these temperatures. In particular, the influence of graphene oxide (GO) and reduced graphene oxide (rGO) on emulsion stability and on thermal and optical properties of PCMEs has been investigated. The stability of emulsions was verified and no phase separation or significant growth of PCM droplets were observed through storage and after freeze–thaw cycles. GO was less successful in case of paraffin melting at 21 °C, while it was effective in reducing subcooling to only 1 °C for nanoemulsion with paraffin melting at 55 °C and strongly influenced heat transfer capability. This resulted in a fluid thermal capacity increase of more than 20% within 10 °C from PCM melting temperature. The partial reduction of GO did not result in significantly changing the thermal properties of nanoemulsions and slightly increased the optical absorption, due to higher optical absorption of rGO with respect to GO.

The electrochemiluminescence (ECL) performances were comparatively investigated at flat and nanoporous gold (NPG) electrodes of different thicknesses (120 and 200 nm) and roughness factors (fr). The phenomena were studied using either tripropylamine (TPrA) or peroxydisulfate (S2O82−) as sacrificial coreactant and Ruthenium (II)-tris(2,2′-bipyridine) as emitting species. The experiments performed using TPrA showed, at first glance, a linear dependence of the ECL emission with respect to the effective surface area of the NPG electrodes. However, ECL signals were not stable in the measuring conditions, presumably due to amine absorption on the metal surface, leading to electrode corrosion and modification of the surface morphology. The experiments made using peroxydisulfate as coreactant provided conversely a stable ECL response, about proportional to the effective electrode surface area, in the considered range of thicknesses.

Nifedipine (NIF) is a hydrophobic drug widely used for treating cardiovascular diseases. This calcium channel blocker can present a higher apparent solubility by its inclusion into different cyclodextrins (CDs) as host-guest complexes. This paper focused on the structural investigation and dissolution behavior of inclusion complexes prepared with 2-hydroxypropyl- β -cyclodextrin (HPβCD) or β -cyclodextrin (βCD) and NIF. Drug amorphization was observed for HPβCD/NIF and βCD/NIF inclusion complexes by X-ray diffractometry (XRD). The sharp endothermic peak of NIF was not observed for these both host-guest complexes by differential scanning calorimetry (DSC). These results of XRD and DSC provide evidences of complexation between drug and the investigated CDs. 1 H and saturation transfer difference nuclear magnetic resonance studies revealed the enhancement in the signal at 2.27 ppm for HPβCD/NIF and βCD/NIF inclusion complexes that corresponded to the methyl groups of NIF from the non-aromatic ring. This result suggested that non-aromatic ring of NIF was inserted into HPβCD and βCD cavities. Considering the mathematical simulations, it was observed that the inclusion process can occur in the both NH-in or NH-out forms. However, since it was used aqueous medium, it is possible to indicate that the obtained host-guest complexes HPβCD/NIF and βCD/NIF are in NH-in form which corresponded to the previous results obtained by 1 H NMR experiments. Dissolution assays demonstrated that NIF inclusion complexes improved the drug release nevertheless without changing its biexponential release behavior. These host-guest complexes can be further used as feasible NIF carriers in solid dosage forms.

Four new compounds were isolated from the tubers of Sinningia canescens and S. leucotricha: one naphthoquinone, 7-methoxy-8-hydroxy-α-dunnione (1); two arylbenzofurans, sinningial A (2) and B (3); and one sesquiterpene, 11-epi-subergorgiol (4). Seventeen additional known compounds were isolated and identified. The structures of all compounds were determined by spectroscopic and MS analysis.

A theoretical and experimental DFT study of the vibrational, structural, and quantum properties of 9-methoxy-canthin-6-one (I) and 7-methoxy-(9H-β-carbolin-1-il)-(Z)-prop-2-enoic acid (II) alkaloids is presented using B3LYP exchange-correlation functional with 6-311G(2d,p) basis set. The theoretical geometry optimization data of both structures were compared with the X-ray data for a similar structure in the associated literature and a conformational study is presented for (II), providing a good comprehension of its conformers’ stability. In addition, natural bond orbitals (NBOs), HOMO-LUMO energy gap, mapped molecular electrostatic potential surface (MEPS) calculations, and first- and second-order hyperpolarizabilities were also performed at the same calculation level. The calculated UV spectra agreed well with the measured experimental data, with transitions assigned. Calculated HOMO/LUMO energy gaps revealed the excitation energy of the structures, justifying their stability and kinetics reaction. IR studies showed that for structure II the intramolecular hydrogen bond of the conformations and the intermolecular hydrogen bonds of the dimeric form influence the results and also revealed several characteristic vibrations for both structures. Molecular docking studies with DNA topoisomerase II-DNA complex showed binding free energies of − 8.4 and − 9.6 kcal/mol for II and I, respectively, while for amsacrine, used for the treatment of leukemia, the binding free energy ΔG presented a value of − 9.9 kcal/mol, showing a good binding affinity of alkaloid I.

This work evaluated the influence of drought and nitrogen fertilization on the fatty acid composition of Jatropha curcas seeds by means of 1H HR-MAS NMR, a tool which allows obtaining chemical information directly from the seeds. It was found that only the drought conditions led to the decrease of polyunsaturated fatty acid contents and to the increase of those monounsaturated. No changes were observed for the contents of saturated fatty acids. The lipid profile reached without irrigation may be considered the most effective for improving biodiesel properties, such as cetane number and oxidative stability. At last, there was no influence on the fatty acid composition with different levels of nitrogen fertilizer application.

The present study aimed to identify and screen the antibacterial activity of a mixture of sesquiterpene lactones (SLs) obtained from the dichloromethane extract of Smallanthus sonchifolius leaves. Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella enterica strains were used as bacterial tests. The identification and quantification of compounds were established by GC/MS and 1H, 13C 2D NMR spectroscopic analysis. The antimicrobial activity was measured by the disk diffusion method and minimal inhibitory concentration assay (MIC). In vitro antimicrobial assays showed that the mixture of SLs found (uvedalin and enhydrin) displays poor antibacterial activity against the Gram-negative bacteria and appreciable antibacterial properties against the Gram-positive bacterial strain tested when 90 µg of the SLs mixture per disk was used. The MIC determination against S. aureus revealed that a concentration of 750 µg of SLs mixture mL−1 should be necessary to inhibit the strain. These results indicate that the SLs mixture of enhydrin and uvedalin from yacon leaves presents promising antibacterial properties against S. aureus and apparent lack of activity against the Gram-negative bacterial strains tested at the concentrations applied.

The new protic ionic liquids mixtures properties and water are of great interest from a theoretical perspective. The objective of this study is to establish mixtures with different densities, viscosities, composition ranges and temperatures. The studied ionic liquids are N-methyl-2-hydroxy-ethylammonium acetate (m-2HEAA), N-methyl-2-hydroxy-ethylammonium propionate (m-2HEAPr) and N-methyl-2-hydroxy-ethylammonium butanoate (m-2HEAB), all based on the N-methyl-2-hydroxy-ethylammonium cation. The excess volume data are correlated using the Prigogine-Flory-Patterson equation of state (EOS) to evaluate the importance of their contributions with respect to the studied mixtures. The viscosity data were modeled combining Eyring mixture law for viscosity and excess Gibbs energy from Flory-Huggins model. The results reveal a large range of negative deviation and a non-significant contribution of the free EOS volume term compared to the interactional contribution and characteristic pressure terms. In general, the models studied in this work presented good agreement with the experimental data.