Chemical Characterization, Antioxidant Capacity and Anti-Oxidative Stress Potential of South American Fabaceae Desmodium tortuosum.

It has been proposed that oxidative stress is a pathogenic mechanism to induce cytotoxicity and to cause cardiovascular and neuronal diseases. At present, natural compounds such as plant extracts have been used to reduce the cytotoxic effects produced by agents that induce oxidative stress. Our study aimed to evaluate the antioxidant and cytoprotective capacity of Desmodium tortuosum (D. tortuosum) extract in the co- and pre-treatment in EA.hy926 and SH-SY5Y cell lines subjected to oxidative stress induced by tert-butylhydroperoxide (t-BOOH). Cell viability, reactive oxygen species (ROS), nitric oxide (NO), caspase 3/7 activity, reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR), and molecular expression of oxidative stress biomarkers (SOD2, NRF2 and NFκB1) and cell death (APAF1, BAX, Caspase3) were all evaluated. It was observed that the D. tortuosum extract, in a dose-dependent manner, was able to reduce the oxidative and cytotoxicity effects induced by t-BOOH, even normalized to a dose of 200 µg/mL, which would be due to the high content of phenolic compounds mainly phenolic acids, flavonoids, carotenoids and other antioxidant compounds. Finally, these results are indicators that the extract of D. tortuosum could be a natural alternative against the cytotoxic exposure to stressful and cytotoxic chemical agents.

Determination of ochratoxin A in coffee and tea samples by coupling second-order multivariate calibration and fluorescence spectroscopy.

A new method to quantify the mycotoxin ochratoxin A (OTA) in coffee and tea samples is proposed based on second-order multivariate calibration and excitation-emission fluorescence matrix (EEFM) data. Experimental conditions were optimized by studying the effect of pH and various organized media on the fluorescence signal of OTA. For each analysed matrix (coffee grains and tea leaves), several sample pretreatments and calibration methods (external or standard addition) and data processing by chemometric models (e.g., parallel factor analysis/PARAFAC and multivariate curve resolution-alternating least squares/MCR-ALS) were evaluated and discussed. The MCR-ALS algorithm provided an adequate fit to the data for both samples, while PARAFAC was satisfactory only for the tea samples. Regarding the figures of merit, the limits of detection were in the range of 0.2-0.3 ng mL-1; furthermore, low relative prediction errors, between 2% and 4%, were achieved in both the fortified and real samples. Accordingly, the proposed methodology was applied to analyse fortified roasted and green coffee and real tea leaf samples. Satisfactory recoveries were achieved (ranging from 92 to 110%), and the obtained concentrations were in agreement with the values obtained by the reference method (based on high-performance liquid chromatography with fluorescence detection/HPLC-FLD). In addition, all samples contained OTA levels lower than the maximum permissible levels. Finally, the proposed strategy allows the use of green analytical chemistry principles; for instance, the use of organic solvents and the generation of waste products were significantly lower than for similar analytical methods reported in the literature.

Synthesis of citrophilus mealybug sex pheromone using chrysanthemol extracted from Pyrethrum ( Tanacetum cinerariifolium).

A commercial pyrethrum extract was used as a source of chrysanthemol for the synthesis of the citrophilus mealybug ( Pseudococcus calceolariae) sex pheromone. The chrysanthemic acid esters (pyrethrins I) were isolated and subsequently reduced to obtain chrysanthemol, which was used for ester pheromone synthesis. Field tests showed that the pheromone synthesized using plant-derived chrysanthemol was as attractive to male P. calceolariae as the pheromone obtained using a commercial isomeric chrysanthemol mixture.

Effect of a Toothpaste/Mouthwash Containing Carica papaya Leaf Extract on Interdental Gingival Bleeding: A Randomized Controlled Trial.

Clinical research on herbal-based dentifrice +/- mouth rinse products is very limited compared with the plethora of research on conventional oral care products under normal oral hygiene conditions. The aim of this study was to determine the anti-inflammatory effects of a novel plant Carica papaya leaf extract (CPLE) on interdental bleeding in healthy subjects. In this randomized, single-blind parallel-design study, the eligible subjects were generally healthy non-smokers, aged 18⁻26, who exhibited healthy periodontal conditions upon study entry. The participants were equally randomized into the following four groups: CPLE dentifrice, CPLE dentifrice and mouthwash, sodium lauryl sulfate (SLS)-free enzyme-containing dentifrice and SLS-free enzyme-containing dentifrice with essential oil (EO) mouthwash. Subjects were instructed to brush their teeth twice a day without changing their other brushing habits. Interdental bleeding (BOIP) was measured from inclusion (T0) until the fourth week (T4) of the study. Clinical efficacy was assessed after one, two, three and four weeks of home use. The analyses compared BOIP between groups and were then restricted to participants with ≥70% and then ≥80% bleeding sites at T0. Pairwise comparisons between groups were performed at T0 and T4, and a logistic regression identified correlates of gingival bleeding (T4). Among 100 subjects (2273 interdental sites), the median percentage of bleeding sites per participant at T0 was 65%. The bleeding sites dramatically decreased in all groups between T0 and T4 (relative variations from -54% to -75%, p < 0.01 for all). Gingival bleeding did not significantly differ between the CPLE dentifrice and the SLS-free dentifrice +/- EO mouthwash groups (from p = 0.05 to p = 0.86), regardless of the baseline risk level. Among the CPLE dentifrice users, fewer bleeding sites were observed when toothpaste and mouthwash were combined compared to bleeding sites in those who used toothpaste alone (21% vs. 32%, p = 0.04). CPLE dentifrice/mouthwash provides an efficacious and natural alternative to SLS-free dentifrice +/-EO-containing mouthwash when used as an adjunct to mechanical oral care to reduce interdental gingival inflammation.

Feasibility of the determination of polycyclic aromatic hydrocarbons in edible oils via unfolded partial least-squares/residual bilinearization and parallel factor analysis of fluorescence excitation emission matrices.

The possibility of simultaneously determining seven concerned heavy polycyclic aromatic hydrocarbons (PAHs) of the US-EPA priority pollutant list, in extra virgin olive and sunflower oils was examined using unfolded partial least-squares with residual bilinearization (U-PLS/RBL) and parallel factor analysis (PARAFAC). Both of these methods were applied to fluorescence excitation emission matrices. The compounds studied were benzo[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[g,h,i]perylene and indeno[1,2,3-c,d]-pyrene. The analysis was performed using fluorescence spectroscopy after a microwave assisted liquid-liquid extraction and solid-phase extraction on silica. The U-PLS/RBL algorithm exhibited the best performance for resolving the heavy PAH mixture in the presence of both the highly complex oil matrix and other unpredicted PAHs of the US-EPA list. The obtained limit of detection for the proposed method ranged from 0.07 to 2 µg kg(-1). The predicted U-PLS/RBL concentrations were satisfactorily compared with those obtained using high-performance liquid chromatography with fluorescence detection. A simple analysis with a considerable reduction in time and solvent consumption in comparison with chromatography are the principal advantages of the proposed method.

Screening of edible oils for polycyclic aromatic hydrocarbons using microwave-assisted liquid-liquid and solid phase extraction coupled to one- to three-way fluorescence spectroscopy analysis.

The potential of microwave-assisted liquid-liquid and solid phase extraction coupled with fluorescence spectroscopy and employing one- to three-way spectral data was assessed in terms of their capacity for the rapid detection of heavy polycyclic aromatic hydrocarbons (PAHs) in olive and sunflower oils. Tocopherols and pigments groups (chlorophyll and pheophytin) present in oil matrices were the main interference compounds in the detection of PAHs using fluorescence spectroscopy. Partial spectral overlap and inner-filter effects were observed in the emission range of the analytes. The effectiveness of removing these interferences using solid phase extraction (silica, C18 and graphitized carbon black) was examined. Solid phase extraction with silica was the most effective method for the removal of pigments and tocopherol and allowed for the detection of PAHs in edible oils using fluorescence spectroscopy. The limit of detection was observed to depend on the use of one-, two- or three-way fluorescence spectral data in the range of 0.8 to 7.0 µg kg(-1). The individual recoveries of PAHs following the microwave-assisted L-L extraction and SPE with silica were assessed using HPLC-FD with satisfactory results.

Development of an analytical method for antimony speciation in vegetables by HPLC-hydride generation-atomic fluorescence spectrometry.

A new method for antimony speciation in terrestrial edible vegetables (spinach, onions, and carrots) was developed using HPLC with hydride generation-atomic fluorescence spectrometry. Mechanical agitation and ultrasound were tested as extraction techniques. Different extraction reagents were evaluated and optimal conditions were determined using experimental design methodology, where EDTA (10 mmol/L, pH 2.5) was selected because this chelate solution produced the highest extraction yield and exhibited the best compatibility with the mobile phase. The results demonstrated that EDTA prevents oxidation of Sb(III) to Sb(V) and maintains the stability of antimony species during the entire analytical process. The LOD and precision (RSD values obtained) for Sb(V), Sb(III), and trimethyl Sb(V) were 0.08, 0.07, and 0.9 microg/L and 5.0, 5.2, and 4.7%, respectively, for a 100 microL sample volume. The application of this method to real samples allowed extraction of 50% of total antimony content from spinach, while antimony extracted from carrots and onion samples ranged between 50 and 60 and 54 and 70%, respectively. Only Sb(V) was detected in three roots (onion and spinach) that represented 60-70% of the total antimony in the extracts.

Compuestos fenólicos de la fracción metanólica de Bidens pilosa, sobre la neoplasia gástrica, inducida en ratas / Phenolic compounds from Bidens pilosa methanolic fraction on induced gastric neoplasia in rats

Objetivo: Determinar la influencia del extracto etanólico y la fracción metanólica conteniendo compuestos fenólicos y flavonoides de la planta entera de Bidens pilosa L sobre la neoplasia gástrica inducida en ratas con N-nitroso-N-metilurea (NMU). Diseño: Experimental. Lugar: Instituto de Investigaciones Clínicas-Bioterio Facultad de Medicina UNMSM. Material biológico: Ratas albinas cepa Holtzmann machos. Intervenciones: Según Ferraz de Souza y col., 2002, se dispuso de un grupo control normal, un grupo con NMU y grupos de NMU más tratamientos de extracto etanólico y fracción metanólica, a dosis de 300 mg/kg. Para la significancia estadística se consideró la p menor que 0,05. Principales medidas de resultados: Progresión de la neoplasia gástrica inducida en ratas. Resultados: Indican displasia y estadios iniciales de carcinoma en los estómagos de las ratas, lo que fue menos evidente en los animales con tratamiento, siendo mejor el grupo que recibió fracción metanólica. El marcador de estrés oxidativo disminuyó en los grupos que recibieron tratamiento con la planta, resultando mejor la fracción metabólica. Se observó menor cantidad de micronúcleos (genotoxicidad) en los animales que recibieron tratamiento. Conclusiones: El extracto etanólico y la fracción metanólica de Bidens pilosa L en las condiciones experimentales han detenido la progresión de la neoplasia gástrica inducida en ratas.

Objective: To determine the influence of both the ethanolic extract and the methanolic fraction containing phenolic and flavonoids compounds of Bidens pilosa L whole plant on gastric cancer induced in rats with N-nitroso-N-methylurea (NMU). Design: Experimental. Setting: Instituto de Investigaciones Clínicas- Bioterio, Facultad de Medicina UNMSM. Biologic material: Holtzmann male albino rats. Interventions: Following Ferraz de Souza et al., 2002, we had a normal control group, a group with NMU and NMU groups plus treatments with ethanolic extract and methanolic fraction at 300 mg/kg doses. For statistical significance we considered p minor 0,05. Main outcome measures: Progresion of gastric neoplasia induced in rats. Results: Indicate dysplasia and initial stages of carcinoma in the rats stomachs, which was less evident in the animals with treatment, being better the group that received the methanolic fraction. The marker of oxidative stress decreased in the groups that received treatment with the plant, being better the methanolic fraction. We observed less amount of micronuclei (genotoxicity) in the animals that received treatment. Conclusions: In experimental conditions the ethanolic extract and methanolic fraction delayed the advance of gastric cancer induced in rats.