Kinetic Profile of Urine Metabolites after Acute Intake of a Phenolic Compounds-Rich Juice of Juçara (Euterpe edulis Mart.) and Antioxidant Capacity in Serum and Erythrocytes: A Human Study.

The juçara palm tree produces a small spherical and black-purple fruit similar to açaí. It is rich in phenolic compounds, especially anthocyanins. A clinical trial evaluated the absorption and excretion of the main bioactive compounds in urine and the antioxidant capacity in serum and erythrocytes of 10 healthy subjects after juçara juice intake. Blood samples were collected before (0.0 h) and 0.5 h, 1 h, 2 h, and 4 h after a single dose (400 mL) of juçara juice, while urine was collected at baseline and 0-3 and 3-6 h after juice intake. Seven phenolic acids and conjugated phenolic acids were identified in urine deriving from the degradation of anthocyanins: protocatechuic acid, vanillic acid, vanillic acid glucuronide, hippuric acid, hydroxybenzoic acid, hydroxyphenylacetic acid, and ferulic acid derivative. In addition, kaempferol glucuronide was also found in urine as a metabolite of the parent compound in juçara juice. Juçara juice caused a decrease in the total oxidant status of serum after 0.5 h in comparison to baseline values (p < 0.05) and increased the phenolic acid metabolites excretion. This study shows the relationship between the production of metabolites of juçara juice and the total antioxidant status in human serum, indicating evidence of its antioxidant capacity.

Kinetic identification of phenolic compounds and potential production of caffeic acid by Ganoderma lipsiense in solid-state fermentation.

Basidiomycetes fungi have been utilized for the production of several compounds with bioactive properties, such as phenolic compounds. The present work quantified and identified the phenolic compounds produced in a kinetic study (63 days) and evaluated the antimicrobial activity from the extract obtained by Ganoderma lipsiense cultivation in solid-state fermentation using red rice. Phenolic compounds were identified by high-performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) and caffeic acid content was measured by high-performance liquid chromatography with diode-array detection (HPLC-DAD). Caffeic and syringic acids were produced by G. lipsiense. In the control medium (red rice), the following compounds were identified: p-coumaric acid, salicylic acid, ferulic acid and vanillin. High concentrations of caffeic acid (0.977 µg g-1) were measured in 49 days. Antimicrobial activity was investigated against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus using a minimum inhibitory concentration (MIC) technique. Ganoderma lipsiense extract was only effective against P. aeruginosa. These data have proved to be satisfactory in the study of biosynthesis of caffeic acid and antibacterial compounds by G. lipsiense in solid-state fermentation with red rice.

Exploiting green sorbents in rotating-disk sorptive extraction for the determination of parabens by high-performance liquid chromatography with tandem electrospray ionization triple quadrupole mass spectrometry.

In this study, the viability of applying cork and montmorillonite clay modified with ionic liquid as biosorbents in the rotating-disk sorptive extraction technique was investigated. Specifically, this was aimed at the determination of methyl paraben, ethyl paraben, propyl paraben, and isobutyl paraben, with separation/determination by high-performance liquid chromatography coupled with mass spectrometry. The optimization of the method for both biosorbents was performed using multivariate procedures. The extraction efficiencies for the target compounds in aqueous matrices were compared to those obtained using the commercial sorbent Octadecil Silano-C18. The optimum extraction conditions for both natural sorbents were the use of an ammonia solution (pH 10) as desorption solvent and an extraction time of 30 min. The proposed methods show limits of quantification of 0.8 µg/L for cork, 3.0 µg/L for montmorillonite clay and 6.0 µg/L for Octadecil Silano-C18. The relative recoveries from river water and tap water samples ranged from 80.3 to 118.7% and 80.0 to 119.9% for cork and montmorillonite clay modified with ionic liquid, respectively. Relative standard deviations were obtained for intra- and interday precisions of <15% and <19% for cork and <19% and <17% for montmorillonite clay modified with ionic liquid.

Antioxidant and antidepressant-like effects of Eugenia catharinensis D. Legrand in an animal model of depression induced by corticosterone.

This work investigated the antioxidant and antidepressant-like effects of ethyl acetate extract from Eugenia catharinensis in mice treated with corticosterone (20 mg/Kg). The animals received saline or corticosterone (21 days) and, in the last 7 days, they were treated with the extract (50, 125, 200 or 250 mg/Kg) or vehicle. After 24 h, the mice were submitted to the open field and forced swimming tests, after which the hippocampus and cerebral cortex were removed. Our results showed that the extract decreased the immobility time of mice in the forced swimming test and that the extract was able to reverse the effect caused by corticosterone. Corticosterone pre-treatment generated oxidative stress, altering antioxidant enzymes in the nervous tissue. The extract increased the catalase and superoxide dismutase activities and reversed the effects of corticosterone. In the hippocampus, the extract increased superoxide dismutase activity and reversed the increase in catalase activity elicited by corticosterone. We propose that the effects elicited by the Eugenia catharinensis are dependent on the presence of phenolic compounds (gallic acid, protocatechuic acid, syringic acid, 4-hydroxy methylbenzoic acid, chlorogenic acid, salicylic acid, caffeic acid, vanillic acid, p-coumaric acid, isoquercetin, rutin, ferulic acid, aromadendrin, galangin and apigenin) in this extract, as demonstrated by HPLC-ESI-MS/MS.

Effects of 1,3,5-triphenyl-4,5-dihydro-1H-pyrazole derivatives on cell-cycle and apoptosis in human acute leukemia cell lines.

Pyrazoline is an important 5-membered nitrogen heterocycle that has been extensively researched. Ten derivatives were synthesized and tested for antileukemic effects on 2 human acute leukemia cell lines, K562 and Jurkat. The most cytotoxic of these derivatives, compound 21, was chosen for investigation of cytotoxicity mechanisms. The results obtained with selectivity calculations revealed that compound 21 is more selective for acute leukemia (K562 and Jurkat cell lines) than for other tumor cell lines. Moreover, compound 21 was not cytotoxic to normal cell lines, indicating a potential use in clinical tests. Compound 21 caused a significant cell cycle arrest in the S-phase in Jurkat cells and increased the proportion of cells in the sub G0/G1 phase in both cell lines. Cells treated with compound 21 demonstrated morphological changes characteristic of apoptosis in the EB/AO assay, confirmed by externalization of phosphatidylserine by the annexin V - fluorescein isothiocyanate method and by DNA fragmentation. An investigation of cytotoxicity mechanisms suggests the involvement of an intrinsic apoptosis pathway due to mitochondrial damage and an increase in the ratio of mitochondrial Bax/Bcl2. Pyrazoline 21 obeyed Lipinski's "rule of five" for drug-likeness. Based on these preliminary results, the antileukemic activity of compound 21 makes it a potential anticancer agent.

Fast and sensitive method to determine parabens by capillary electrophoresis using automatic reverse electrode polarity stacking mode: application to hair samples.

This paper describes a fast and sensitive method for the determination of methyl, ethyl, propyl, and butylparaben in hair samples by capillary electrophoresis using automatic reverse electrode polarity stacking mode. In the proposed method, solutions are injected using the flush command of the analysis software (940 mbar) and the polarity switching is carried out automatically immediately after the sample injection. The advantages compared with conventional stacking methods are the increased analytical frequency, repeatability, and inter-day precision. All analyses were performed in a fused silica capillary (50 cm, 41.5 cm in effective length, 50 µm i.d.), and the background electrolyte was composed of 20 mmol L(-1) sodium tetraborate in 10 % of methanol, pH 9.3. For the reverse polarity, -25 kV/35 s was applied followed by application of +30 kV for the electrophoretic run. Temperature was set at 20 °C, and all analytes were monitored at 297 nm. The method showed acceptable linearity (r (2) > 0.997) in the studied range of 0.1-5.0 mg L(-1), limits of detection below 0.017 mg L(-1), and inter-day, intra-day, and instrumental precision better than 6.2, 3.6, and 4.6 %, respectively. Considering parabens is widely used as a preservative in many products and the reported possibility of damage to the hair and also to human health caused by these compounds, the proposed method was applied to evaluate the adsorption of parabens in hair samples. The results indicate that there is a greater adsorption of methylparaben compared to the other parabens tested and also dyed hairs had a greater adsorption capacity for parabens than natural hairs.

A Rapid Method for Analysis of Phenylalanine in Cereal Products by MEKC-UV Using LC/MS/MS as a Comparative Method.

The aim of this study was to develop a new and fast micellar electrokinetic chromatography (MEKC) method for the determination of phenylalanine in cereal samples. The background electrolyte was chosen by a factorial design and was composed of 30 mmol/L phosphoric acid, 100 mmol/L sodium dodecyl sulfate, and 25% methanol (v/v) at pH 1.9. A fused silica capillary (48.5 cm total length×8.5 cm effective length×50 µm id×375 µm od) was used in a short-end injection configuration, and direct UV detection was at 200 nm. The method was validated following the Eurachem guidelines, and values such as linearity (from 10.1 to 40.4 mg/L); recovery (86.8-103.9%); repeatability (0.06-0.22% for migration time and 1.14-4.82% for peak area); reproducibility (0.04-0.61% for migration time and 2.22-5.72% for peak area); and LOD and LOQ of 20 and 60 mg/100 g, respectively, were obtained. After the comparison involving selectivity and accuracy between capillary electrophoresis and LC/MS/MS method, the MEKC-UV method was successfully applied to analysis of phenylalanine in different cereal products.

Croton antisyphiliticus Mart. attenuates the inflammatory response to carrageenan-induced pleurisy in mice.

The aim of this study was to investigate the anti-inflammatory effect of the crude hydroalcoholic extract (CHE) from the aerial parts of Croton antisyphiliticus, its fractions and isolated compounds derived from it on the mouse model of pleurisy induced by carrageenan. The aerial parts of C. antisyphiliticus were dried, macerated and extracted with ethanol to obtain the CHE, which was fractionated by liquid-liquid extraction using solvents with increasing polarity to obtain hexane (Hex), ethyl acetate (EA) and aqueous (Aq) fractions. Vitexin and quinic acid were isolated from Aq fraction. Capillary electrophoresis analysis, physical characteristics and spectral data produced by infrared (IR), nuclear magnetic resonance ((1)H and (13)C NMR) and mass spectrometry analyses were used to identify and elucidate the structure of the isolated compounds. The experimental model of pleurisy was induced in mice by a single intrapleural injection of carrageenan (1 %). Leukocytes, exudate concentrations, myeloperoxidase (MPO) and adenosine-deaminase (ADA) activities and nitrate/nitrite (NOx), tumor necrosis factor-α (TNF-α) and interleukin-17 (IL-17) levels were determined in the pleural fluid leakage at 4 h after pleurisy induction. Animals pre-treated with CHE, Hex, EA, Aq, vitexin and quinic acid exhibited decreases in leukocytes, exudate concentrations, MPO and ADA activities and NOx levels (p < 0.05). Also CHE, Hex, EA and vitexin but not quinic acid inhibited TNF-α and IL-17 levels (p < 0.05). C. antisyphiliticus caused anti-inflammatory effect by inhibiting the activated leukocytes, exudate concentrations, NOx, TNF-α, and IL-17 levels. The compounds vitexin and quinic acid may be responsible for this anti-inflammatory action.

Analysis of the UV filter Benzophenone-3 assimilation in Crossostrea gigas oysters post-exposure in a controlled environment by LC-MS/MS.

Benzophenone-3 (BP-3), utilized as a UV filter in cosmetic products, is an emerging contaminant that constitutes a threat to natural resources and environmental health. This study investigated the assimilation of the UV filter BP-3 in Crassostrea gigas oysters collected in Florianópolis, Santa Catarina, Brazil. Lyophilized oyster tissue extracts were prepared using the QuEChERS method, and LC-MS/MS was employed to determine the BP-3 concentration in the samples. The method was applied to specimens intentionally exposed to two concentrations of the contaminant, for different periods of exposure (1 and 7 days). Samples from treatment 1 (T1) were exposed to a concentration of 1 µg L-1 of the BP-3 standard, and samples from treatment 2 (T2) were exposed to a concentration of 100 µg L-1 of the BP-3 standard. The results revealed rapid absorption of BP-3, with an increase of 126% for lower concentrations, reaching 1.13 µg of BP-3 per gram of oyster tissue, and 17% for higher concentrations, reaching 34.6 µg of BP-3 per gram of oyster tissue after 7 days. The presence of BP-3 even in samples not directly exposed to the contaminant indicates its widespread environmental distribution. The rapid bioaccumulation suggests the need to consider seasonal variations, such as increased tourism in the summer. The validated analytical method demonstrated efficacy in quantifying BP-3, providing an integrated approach for long-term monitoring of pollution levels and their dynamic variations over time. In addition, variation in BP-3 levels in the samples may be related to transport patterns influenced by tides and discharges from septic system, highlighting the need to improve wastewater treatment. These findings underscore the necessity for continuous biomonitoring and effective environmental management to safeguard the health of marine ecosystems and humans.

Effects of Myrcia pubipetala Miq (Myrtaceae) extract on innate inflammatory response.

Myrcia is a genus widespread in South America with many species presenting anti-inflammatory and biological properties. We investigated the anti-inflammatory activity of crude hydroalcoholic extract of Myrcia pubipetala leaves (CHE-MP) using macrophages (RAW 264.7), and the air pouch model in mice to evaluate leukocyte migration and mediator's release. Adhesion molecule expression, CD49 and CD18, was evaluated in neutrophils. In vitro, the CHE-MP significantly reduced nitric oxide (NO), interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF) levels in the exudate and the supernatant culture. CHE-MP did not present cytotoxicity and modulated the percentage of positive neutrophils for CD18 and its expression per cell, without modifying the expression of CD49, which corroborated with significantly reduced neutrophil migration to inflammatory exudate and subcutaneous tissue. Taken together, the data demonstrate that CHE-MP presents a potential activity on innate inflammatory.

First report on the electrooxidation of vinpocetine using a modification free sensing platform: application to pharmaceutical formulations.

This study presents the first insights into vinpocetine (VIN) behavior, a nootropic compound, on a glassy carbon electrode (GCE). Cyclic voltammetry (CV) revealed an irreversible oxidation peak at +1.0 V (vs. Ag/AgCl), with pH dependency indicating proton involvement in the electrochemical reaction. Density functional theory (DFT) optimized VIN's molecular geometry, while Fukui functions and dual descriptors elucidated its reactivity for a more straightforward exploration of the complete electrooxidation mechanism. Differential pulse voltammetry (DPV) demonstrated VIN sensing capabilities within a concentration range of 0.20 to 12.8 mg L-1, with a theoretical limit of detection (LOD) at 0.07 mg L-1, using optimized conditions of supporting electrolyte. The method showed selectivity in the presence of excipients and interfering species commonly found in pharmaceutical formulations. Recovery tests yielded 95.5% (n = 3), and quantification in pharmaceutical formulations showed no significant differences compared to the reference method based on HPLC DAD. This novel electroanalytical method holds promise for VIN nootropic sensing and routine pharmaceutical analysis.

Method development for determination of (+)-catechin and (-)-epicatechin by micellar electrokinetic chromatography: annual characterization of field grown blackberries.

Berries are a rich source of antioxidants compounds, among which is the catechin group. Determination of the monomers (catechin and epicatechin) in fruits is a first step in the way to establish a relationship between polyphenols and their effects on human health. The purpose of this work is to develop a method to determine free catechins in blackberry by MEKC and to characterize levels of catechins in fresh fruits of Rubus fruticosus var. Lochness throughout the annual production period. A methanolic extract was prepared from fresh fruit. Then, it was evaporated and the residue was extracted with diethyl ether. MEKC conditions: phosphoric acid, 30 mmol/L; SDS, 40 mmol/L and triethylamine, 0.1% v/v at pH 2.3; -15 kV of voltage; 10-s hydrodynamic injection; 25°C temperature; and detection at 200 nm. Instrumental and interday precision were lower than 4.7 and 10% RSD, respectively. Only (-)-epicatechin was quantified in blackberries and ranged from 120 to 620 mg/kg fresh weight, which were the lowest values in December and the highest in June. A solid-liquid extraction and an MEKC method were successfully applied to determine (-)-epicatechins in blackberry for the first time. A strong dependence of (-)-epicatechin on the annual average temperature was observed.

Simultaneous determination of free and total glycerol in biodiesel by capillary electrophoresis using multiple short-end injection.

A rapid method for the simultaneous determination of free glycerol (FG) and total glycerol (TG) in biodiesel by CE using a short-end multiple injection (SE/MI) configuration system is described. The sample preparation for FG involves the extraction of glycerol with water and for TG a saponification reaction is carried out followed by extraction as in the case of FG. The glycerol extracted in both cases is submitted to periodate oxidation and the iodate ions formed are measured on a CE-SE/MI system. The relevance of this study lies in the fact that no analytical procedure has been previously reported for the determination of TG (or of FG and TG simultaneously) by CE. The optimum conditions for the saponification/extraction process were 1.25% KOH and 25°C, with a time of only 5 min, and biodiesel mass in the range of 50.0-200.0 mg can be used. Multiple injections were performed hydrodynamically with negative pressure as follows: 50 mbar/3s (FG sample); 50 mbar/6s (electrolyte spacer); 50 mbar/3s (TG sample). The linear range obtained was 1.55-46.5 mg/L with R(2) > 0.99. The LOD and LOQ were 0.16 mg/L and 0.47 mg/L, respectively for TG. The method provides acceptable throughput for application in quality control and monitoring biodiesel synthesis process. In addition, it offers simple sample preparation (saponification process), it can be applied to a variety biodiesel samples (soybean, castor, and waste cooking oils) and it can be used for the determination of two key parameters related to the biodiesel quality with a fast separation (less than 30 s) using an optimized CE-SE/MI system.

Systemic administration of Rosmarinus officinalis attenuates the inflammatory response induced by carrageenan in the mouse model of pleurisy.

Rosmarinus officinalis, also named rosemary, is a native plant from the Mediterranean region that is useful for the treatment of inflammatory diseases. Studies using experimental models and/or in vitro tests have shown the important biological effects of rosemary. In this context, the mechanism of the anti-inflammatory activity of rosemary must be investigated to support the discovery of new substances with anti-inflammatory effects. The aim of the present study was to investigate the anti-inflammatory effects of crude extract oil free obtained from the leaves of rosemary in an animal model of inflammation, thus evaluating its medicinal use for the treatment of inflammatory conditions. Also its ethanol, hexane, and ethyl acetate fractions, as well as its isolated compounds carnosol and rosmarinic acid were analyzed. Swiss mice were used for the in vivo experiments. The effect of this herb on the inhibition of the leukocytes, exudation, myeloperoxidase, and adenosine-deaminase activities, nitrite/nitrate, interleukin 17A, and interleukin 10 levels and mRNA expression was determined. The crude extract and its derived fractions, in addition to its isolated compounds, inhibited leukocytes and decreased exudation and myeloperoxidase and adenosine-deaminase activities, as well as nitrite/nitrate and interleukin 17A levels and mRNA expression, besides increasing interleukin 10 levels and mRNA expression. Rosemary showed important anti-inflammatory activity by inhibiting leukocytes and decreasing exudation. These effects were associated with a decrease in the proinflammatory parameters (myeloperoxidase, adenosine-deaminase, nitrite/nitrate, and interleukin 17A) and an increase in the anti-inflammatory cytokine (interleukin 10). This study confirms the anti-inflammatory properties of rosemary and validates its use in folk medicine to treat inflammatory diseases such as rheumatism and asthma.

Antiulcer effect of bark extract of Tabebuia avellanedae: activation of cell proliferation in gastric mucosa during the healing process.

Tabebuia avellanedae (syn. Handroanthus impetiginosus) is popularly known as 'ipê-roxo' and has been used in folk medicine as anti-inflammatory and in the treatment of ulcers, bacterial and fungal infections. This study evaluated the gastric ulcer healing property of the ethanolic extract (EET) of barks from Tabebuia avellanedae and investigated the mechanisms that may underlie this effect. Rats were treated with EET (twice a day for 7 days) after induction of chronic gastric ulcers by 80% acetic acid. Following treatment, histological and immunohistochemical analysis were performed in gastric ulcer tissues. Oral administration of EET (100 and 300 mg/kg) significantly reduced the gastric lesion induced by acetic acid in 44 and 36%, respectively. Histopathological evaluation demonstrated a contraction of gastric ulcer size, increase of mucus layer (periodic acid-Schiff stained mucin-like glycoproteins) and cell proliferation (proliferating cell nuclear antigen immunohistochemistry) in animals treated with EET (100 and 300 mg/kg). The results demonstrate that EET significantly accelerates healing of acetic acid induced gastric ulcer in rats through increase of mucus content and cell proliferation, indicating a potential usefulness for treatment of peptic ulcer diseases.

GC-MS comparison of fatty acids profile of oils extracted from viscera of Tainha (Mugil liza) and Tambaqui (Colossoma macropomum).

The commercial activity of the grey mullet (known as Tainha: TAI) and Tambaqui (TAM) generates tons of waste that can be turned into valuable resources. Therefore, this work aimed to chemically characterize and quantify the fatty acids profiles of the two fishes. GCMS quantification was performed by using calibration curves built from a standard that contains 19 FAME. The analysis revealed that visceral wastes from both fishes contain 16 fatty acids (FA) consisting of saturated (SFA), monounsaturated (MUFA) and polyunsaturated (PUFA). However, their compositions were different as FA side chains in TAI and TAM contain 12 to 20 and 13 to 22 carbon atoms, respectively. Also, the SFA amount in TAI was greater than in TAM. On the other hand, TAM is richer in MUFA and PUFA compared to TAI. Both have similar chemical compositions of ω-3 and ω-6 in PUFA and ω-5, ω-7, and ω-9 in MUFA.

Immobilized acetylcholinesterase in magnetic nanoparticles for in-line inhibition studies using a capillary electrophoresis system.

Enzyme assays can be performed with the capillary electrophoresis technique (CE) in many approaches, such as the immobilized enzyme micro-reactor. Acetylcholinesterase is a promising enzyme to be used when pursuing such a method, as it has already been explored in the proposal of similar methods of miniaturizing enzyme assays. The present work proposes a novel enzyme micro-reactor, based on the anchorage of the enzyme on magnetic nanoparticles of MnFe2O4, with chitosan and glutaraldehyde as the cross-linker in the capillary by means of an arrange of neodymium magnets. The calculated Km of the enzyme evaluated by this method was 1.12 mmol L-1, comparable to other studies in the literature that utilizes immobilized enzymes. Also, IC50 for neostigmine was assessed in 3 different micro-reactors, with an average of 29.42 ± 3.88 µmol L-1. In terms of the micro-reactor stability, it was possible to perform at least 25 experiments with assembled micro-reactor. The method was applied to hydroalcoholic extracts of 7 plant species. Plinia cauliflora had the best result, with 42.31 ± 6.81% of enzyme inhibition in a concentration of 100 mg L-1.

Optimisation of a capillary zone electrophoresis methodology for simultaneous analysis of organic aliphatic acids in extracts of Brachiaria brizantha.

INTRODUCTION: Aluminum toxicity is commonly verified in acidic soils, and poses a severe limitation to plant growth and development. Therefore, Al complexation by the root system mucilage, Al complexation by organic compounds that are exuded by the roots and internal metabolic processes must be monitored by organic acids (OA), since they play a central role in these aluminum tolerance mechanisms. OBJECTIVE: To optimise a capillary zone electrophoresis method able to perform simultaneous separation of acetic, citric, formic, lactic, malic, oxalic, pyruvic, succinic, tartaric and aspartic acid in plant extract solutions. METHODOLOGY: Method optimisation was achieved by a chemometric approach through experimental designs. The optimal condition found was: 20 mmol/L phthalic acid buffer; 0.8 mmol/L cetyltrimethyl-ammonium bromide; pH 3.4 adjusted with tris(hydroxymethyl)aminomethane (around 16 mmol/L); -15 kV of voltage; 25 °C of cartridge temperature; indirect ultraviolet detection at 240 nm; and 25 mbar injection for 2 s, within an analysis time of 4 min. RESULTS: As a repeatability test of the optimal condition, 30 replicates were carried out with the same working electrolyte, where the relative standard deviation of each peak ranged from 0.081 to 0.36% (for migration time) and from 2.4 to 4.6% (for peak area). CONCLUSION: The methodology was successfully applied to simultaneously determine citric, malic and aspartic acid in roots and leaves extract solutions of Brachiaria brizantha, demonstrating its usefulness to study aluminum tolerance.

Phenolic compounds of Eugenia involucrata (Myrtaceae) extracts and associated antioxidant and inhibitory effects on acetylcholinesterase and α-glucosidase.

Eugenia involucrata DC. (Myrtaceae), popularly known as "cereja-do-Rio-Grande", is a native tree from Brazil, popularly used as a hypoglycemiant. Crude hydroalcoholic extract (CHE) and fractions (insoluble (FI), dichloromethane (FDM), ethyl acetate (FEA) and butanol (FBu)) of leaves were assessed to determine the phenolic chemical composition by HPLC-ESI-MS/MS. 10 compounds were identified, being 7 new for this species: rutin, isoquercitrin, luteolin-7-O-rutinoside, mandelic acid, naringenin, luteolin-7-O-glucoside and salicylic acid. Extract and fractions showed inhibitory activity on acetylcholinesterase (AchE) enzyme (best result: IC50 = 44.19 µg mL-1, for FEA) and α-glucosidase (α-Glu) (best result: IC50 = 31.25 ± 0.15 µg mL-1, for CHE). The observed antioxidant and inhibitory activity on the AchE and α-Glu is due to, at least in part, the presence of phenolic compounds in the samples.

Dual electrophoretically-mediated microanalysis in multiple injection mode for the simultaneous determination of acetylcholinesterase and α-glucosidase activity applied to selected polyphenols.

Acetylcholinesterase (AChE) and α-glucosidase (α-glu) are key target enzymes in the search for novel strategies in the treatment of Alzheimer's disease and type II diabetes. Therefore, methods to assess the enzyme inhibition are of great value in the research field. Here is proposed a novel a dual electrophoretically-mediated microanalysis for the simultaneous determination of both enzymes' activity. In order to do so, the various solutions required for both assays were introduced in the capillary electrophoresis system using the multiple injections approach. Enzymatic kinetic parameters were tested, Km for AChE and α-glu were 3.81 and 0.43 mmol L-1. Ki values were 4.27 µmol L-1 for neostigmine (an AChE inhibitor) and 0.40 mmol L-1 for acarbose (an α-glu inhibitor). Results of IC50 (concentration for 50% of inhibition) were 5.11 ± 0.47 µmol L-1 and 0.58 ± 0,02 mmol L-1 for neostigmine and acarbose, respectively. All parameters (except for Ki of neostigmine) were comparable with the literature, indicating a good reliability of the proposed method to evaluate these enzymes activity. Total time analysis was approximately 10 min, being possible to perform around 12 enzymatic assays per hour, with low sample and reagent consumption, thus satisfying some of the principles of green chemistry. The method was applied to evaluate 10 phenolic compounds, of wich p-coumaric acid showed the best inhibitory activity for AChE (40.14 ± 4.75% at 10 mg L-1); and quercetin for α-glu (46.53 ± 4.90% at 10 mg L-1).