Levels of phenylpropanoids and iridoids in extracts and infusions of Verbena minutiflora.

Herein we report for the first time the levels of phenylpropanoids and iridoids in extracts and infusions of V. minutiflora consumed in Brazil to treat urinary and infectious disorders. An in house validation study demonstrated good accuracy and precision to determine the bioactive compounds in V. minutiflora by HPLC-DAD. Phenylpropanoids varied in the extracts (leaves 139.70 to 221.20 mg g-1, flowers 106.43 to 227.22 mg g-1, stems 42.18 to 56.48 mg g-1). Verbascoside occurred in higher concentration in extracts of leaves (87.66 - 136.16) mg g-1 and flowers (58.12 - 148.96) mg g-1 than in stems (19.24 - 24.62) mg g-1. Iridoids in extracts were as follows: leaves (46.60 - 54.79) mg g-1, flowers (55.88 - 93.87) mg g-1 and stems (40.05 to 61.74) mg g-1. High levels of iridoids (314.70 - 415.10) µg mL-1, phenylpropanoids (1996.39 - 2674.13) µg mL-1 and verbascoside (1029.38 - 1456.42 µg mL-1) in infusions support the popular consume of V. minutiflora.

Direct Determination of Nimesulide in Natural Waters and Wastewater by Cathodic Stripping Voltammetry.

Pharmaceuticals are included in a group of compounds considered as contaminants of emerging concern (CECs) in environmental matrices. The quantification of CECs is typically accomplished using chromatographic methods that require several sample pretreatment steps. The current study proposes a voltammetric method to quantify directly nimesulide (NIM) in aqueous samples. The voltammetric parameters were optimized and chosen based on the profile of the voltammograms and peak current intensity. The adequacy of the analytical method was evaluated using validation criteria, such as accuracy, selectivity, linearity, detection, and quantification limits. Linearity was assessed by a standard addition curve at a concentration range of 0.5-130 µg L-1 of NIM. The limit of quantification was 0.50 µg L-1, with 60 s of preconcentration time. Accuracy was expressed as recovery percentages of NIM and ranged from 111.4 to 119.8%. The voltammetric method herein proposed has several advantages over others already used to determine NIM, such as fewer sample pretreatment steps, faster, and cheaper analyses. NIM was detected in wastewater samples at concentration levels ranging from 101.7 to 385.0 µg L-1. This result is the first evidence about NIM occurrences in environmental matrices in the area surrounding the Itaipu Lake reservoir in Brazil.

In house validation from direct determination of 5-hydroxymethyl-2-furfural (HMF) in Brazilian corn and cane syrups samples by HPLC-UV.

In this work the development and in house validation of the HMF direct determination in corn and cane syrups by HPLC-UV was carried out for the first time. The separation was done with isocratic elution of a mobile phase comprising water (with 0.5% formic acid) and acetonitrile (90:10, v/v) on Phenomenex C18 column (5.0 µm, 4.6 × 150 mm), at 30 °C, flow rate of 0.8 mL min(-1) and detection at 285 nm. The validated method showed excellent performance with low limits (LOD and LOQ of 0.09 and 0.26 mg L(-1), respectively), good accuracy (recovery rates between 100% and 104%) and precision (RSD's for repeatability and intermediate precision between 0.57% and 6.43%). Good selectivity and linearity were also observed. HMF contents in both foods were very high (406.6-2121.3 mg kg(-1) for corn syrup and 109.2-893.1 mg kg(-1) for cane syrup), which arouses concern about food safety of these products.

Antidepressant- and anxiolytic-like activities of an oil extract of propolis in rats.

PURPOSE: Propolis biological effects are mainly attributed to its polyphenolic constituents such as flavonoids and phenolic acids that were recently described in the chemical composition of an extract of propolis obtained with edible vegetal oil (OEP) by our group. The aim of this study was to evaluate the effect of OEP on the behavior of rats. MATERIALS AND METHODS: An in vivo open field (OF), elevated Plus-maze (EPM), and forced swimming (FS) tests were performed to evaluate locomotor activity, anxiolytic- and antidepressant effects of the extract. Besides, oxidative stress levels were measured in rat blood samples after the behavioral assays by evaluation of the Trolox equivalent antioxidant capacity (TEAC) and nitric oxide levels. RESULTS: OEP increased locomotion in the OF test (50mg/kg) and central locomotion and open arm entries in the OF and EPM tests (10-50mg/kg) and decreased the immobility time in the FS test (10-50mg/kg). Moreover, OEP reduced nitric oxide levels in response to swim stress induced in rats. CONCLUSION: OEP exerted stimulant, anxiolytic and antidepressant effects on the Central Nervous System and antioxidant activity in rats, highlighting propolis as a potential therapeutic compound for behavior impairment of anxiety and depression.

Sebastianines A and B, novel biologically active pyridoacridine alkaloids from the Brazilian ascidian Cystodytes dellechiajei.

Fractionation of the crude methanol extract of the ascidian Cystodytes dellechiajei collected in Brazil yielded two novel alkaloids, sebastianine A (1) and sebastianine B (2). The structures of both 1 and 2 were established by analysis of spectroscopic data, indicating an unprecedented ring system for both compounds, comprising a pyridoacridine system fused with a pyrrole unit in sebastianine A (1) and a pyridoacridine system fused with a pyrrolidine system condensed with alpha-hydroxyisovaleric acid in sebastianine B (2). Both alkaloids displayed a cytotoxic profile against a panel of HCT-116 colon carcinoma cells indicative of a p53 dependent mechanism.

Antibacterial activity against resistant bacteria and cytotoxicity of four alkaloid toxins isolated from the marine sponge Arenosclera brasiliensis.

Arenosclerins A-C and haliclonacyclamine E, new tetracyclic alkylpiperidine alkaloids isolated from the marine sponge Arenosclera brasiliensis, were subjected to antimicrobial and cytotoxic bioassays. Fourteen samples of microorganisms were used: Candida albicans, Staphylococcus aureus, Escherichia coli, and 12 antibiotic-resistant bacteria isolated from hospital environment. The minimum inhibitory concentration activity of each alkaloid was determined. The four compounds displayed antibacterial activity, but no antifungal activity against C. albicans. Haliclonacyclamine E and arenosclerins A and C were active against a larger number of bacteria strains than arenosclerin B. However, arenosclerins B and C presented more potent antibacterial activity. The alkaloids displayed inhibitory activity against both Gram positive and Gram negative bacteria. Cytotoxicity bioassays using the MTT method showed that these compounds present cytotoxic activity against human HL-60 (leukemia), L929 (fibrosarcoma), B16 (melanoma) and U138 (colon) cancer cell lines at concentrations between 1.5 and 7.0microg/ml. The results obtained indicated that A. brasiliensis alkaloids have a potent toxic activity. The broad cytotoxic and antimicrobial activities presented by A. brasiliensis alkaloids suggest a defensive role of arenosclerins and haliclonacyclamine E against microbial infection and/or the action of potential predators at the sponge's natural habitat.