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1.
Sci Justice ; 59(2): 190-198, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30798868

RESUMEN

Over the past decades, consume of slimming agents considerably increased in several countries, including Brazil, due to weight-loss and stimulant properties. Since these drugs are controlled to prevent illicit and indiscriminate use, there is a parallel illegal market that uses the Internet and irregular pharmacies in order to distribute these formulations. Slimming agents produced by these illegal sources are known for being manufactured with little or none quality control resulting in uncertain and unknown formulations. For forensic purposes, apprehended pharmaceuticals have to undergo a process of chemical identification that can be difficult due to its complex matrix. In this sense, application of assisted energies in the extraction step such as microwave irradiation can be a promising method to increase the recuperation of the target molecules of the sample. Therefore, the aim of this research was to identify four slimming agents apprehended in Brazil by means of visual inspection, Fourier Transform Infrared Spectroscopy, Differential Scanning Calorimetry and Gas Chromatography - Mass Spectrometry. Moreover, the efficiency of solid-liquid extraction and microwave-assisted extraction was compared. It should be noted that our work was one of the few to use Differential Scanning Calorimetry and the application of microwave irradiation in the analysis of apprehended materials. Results showed that the majority of the samples was counterfeit being composed of one or several adulterants or contaminants. Initially, visual inspection resourcefully screened the slimming agents for possible signs of falsification, however it failed to detect fraudulent products that were very similar to veridical medicines. Sequentially, Fourier Transform Infrared Spectroscopy detected functional groups present in the samples while the presence or absence of the alleged active ingredients were successfully measured with Differential Scanning Calorimetry and, thus, providing a full chemical screening of the apprehended materials. Gas Chromatography- Mass Spectrometry confirmed the presence of adulterants such as caffeine, fluoxetine and phenolphthalein as well as contaminants such as sulfurol in the falsified samples. Finally, comparison of extraction procedures indicated that microwave-assisted extraction increased the recovery of compounds detected in chromatographic analysis to a greater extent than solid-liquid extraction.


Asunto(s)
Depresores del Apetito/análisis , Rastreo Diferencial de Calorimetría , Medicamentos Falsificados/química , Contaminación de Medicamentos , Microondas , Brasil , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía Infrarroja por Transformada de Fourier
2.
Molecules ; 19(5): 5806-20, 2014 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-24806580

RESUMEN

Because of the need for more effective and less harmful antifungal therapies, and interest in the synthesis of new carboximidamides, the goal of this study was to determine the antifungal and anti-enzyme activities of some new pyrazole carboximidamides and their cytotoxicity. For this purpose, tests were performed to evaluate: minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC); production of proteinases and phospholipase, and cytotoxicity of the extracts. Data were analyzed by ANOVA and Tukey Tests (α = 5%). The results were: MIC and MFC ≥ 62.5 µg/mL (C. albicans, C. parapsilosis, C. famata, C. glabrata, and Rhodotorula mucillaginosa) and MIC and MFC ≥ 15.6 µg/mL (C. lipolytica). The values of proteinase and phospholipase (Pz) of C. albicans before and after exposure to the compounds were: 0.6 (±0.024) and 0.2 (±0.022) and 0.9 (±0.074) and 0.3 (±0.04), respectively. These proteinase results were not significant (p = 0.69), but those of phospholipase were (p = 0.01), and 15.6 µg/mL was the most effective concentration. The cytotoxicity means were similar among the tests (p = 0.32). These compounds could be useful as templates for further development through modification or derivatization to design more potent antifungal agents. Data from this study provide evidence that these new pyrazole formulations could be an alternative source for the treatment of fungal infections caused by Candida. However, a specific study on the safety and efficacy of these in vivo and clinical trials is still needed, in order to evaluate the practical relevance of the in vitro results.


Asunto(s)
Antifúngicos/administración & dosificación , Candida/efectos de los fármacos , Micosis/tratamiento farmacológico , Pirazoles/síntesis química , Antifúngicos/síntesis química , Antifúngicos/química , Candida/patogenicidad , Inhibidores Enzimáticos/uso terapéutico , Humanos , Pruebas de Sensibilidad Microbiana , Micosis/patología , Pirazoles/administración & dosificación , Pirazoles/química
3.
Sci Justice ; 61(4): 378-383, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34172126

RESUMEN

Latent fingermarks are important trace evidence found in crime scenes mainly used for identification purposes. Once deposited, the composition of samples changes over time influencing the efficacy of latent fingermark development methods. In this sense, the aims of this work were to characterize the fatty acid (FA) profile of sebaceous latent fingermarks by GC-FID and to preliminarily evaluate the development efficiency of enhancement methods (powder dusting, iodine fuming and silver nitrate method) in a 30-day period of aging under controlled parameters of temperature, photoperiod and humidity. Results showed that myristic (7.51 ± 0.76% - 13.39 ± 1.26%), palmitic (35.91 ± 1.07% - 40.81 ± 2.52%), stearic (6.67 ± 0.36% - 9.13 ± 0.36%) and oleic (18.08 ± 0.25% - 20.93 ± 0.26%) acid varied significantly (p < 0.05) over the 30-day period of analysis. Regarding development efficiency, fluorescent orange powder and the silver nitrate method also increased their efficacy to develop latent fingermarks over time while the iodine fuming method decreased its efficiency. Silver black powder had constant efficacy in the tested period. Changes in the constitution of sebaceous marks possibly influenced the development efficiency of enhancement techniques. This knowledge is important to better understand the kinetic of aging and its influence on the development method.


Asunto(s)
Yodo , Nitrato de Plata , Anciano , Colorantes , Dermatoglifia , Humanos , Polvos
4.
Braz J Microbiol ; 52(3): 1275-1285, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33835420

RESUMEN

Macroalgae comprise a vast group of aquatic organisms known for their richness in phytochemicals. In this sense, the lipophilic profile of five Antarctic seaweed species was characterized by chromatographic and spectroscopic analysis and their antioxidant and antimicrobial potential was evaluated. Results showed there were 31 lipophilic substances, mainly fatty acids (48.73 ± 0.77 to 331.91 ± 10.79 mg.Kg-1), sterols (14.74 ± 0.74 to 321.25 ± 30.13 mg.Kg-1), and alcohols (13.07 ± 0.04 to 91.87 ± 30.07 mg.Kg-1). Moreover, Desmarestia confervoides had strong antioxidant activity, inhibiting 86.03 ± 1.47% of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical at 1 mg.mL-1. Antimicrobial evaluation showed that extracts from Ulva intestinalis, Curdiea racovitzae, and Adenocystis utricularis inhibited the growth of Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), and Salmonella typhimurium (ATCC 14028) from concentrations of 1.5 to 6 mg.mL-1. Therefore, the evaluated brown, red, and green macroalgae contained several phytochemicals with promising biological activities that could be applied in the pharmaceutical, biotechnological, and food industries.


Asunto(s)
Antibacterianos , Antioxidantes/farmacología , Algas Marinas , Regiones Antárticas , Antibacterianos/farmacología , Phaeophyceae/química , Fitoquímicos/farmacología , Rhodophyta/química , Algas Marinas/química , Ulva/química
5.
RSC Adv ; 10(4): 2327-2336, 2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-35494560

RESUMEN

The synthesis of monoacylglycerol (MAG) through the glycerolysis of ethyl ester mixture (biodiesel) was investigated in this study from linseed oil, low-cost alternative feedstock, using an alkaline catalyst with green reagent. The transesterification double step process (TDSP), reaction with ethanol to ethyl esters yielded 97%. In the glycerolysis reaction, the optimum operating condition was in a temperature of 130 °C with 5% sodium hydroxide (NaOH) in 1 : 5 biodiesel-glycerol and 12 h reaction time, in open reactor. The reaction conditions showed an interesting conversion and monoacylglycerol yield of 98% and 76%, respectively. The determination and characterization of reaction products was carried out by Gas Chromatography (GC) method, Infrared Spectroscopy (IR), Thermogravimetric Analysis (TGA) and Hydrogen Nuclear Magnetic Resonance Spectroscopy (1H NMR).

6.
Drug Test Anal ; 12(9): 1264-1273, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32537903

RESUMEN

Anabolic androgenic steroids (AASs) comprise a class of synthetic androgens resulting from chemical modifications of testosterone, known for their illicit consumption, which can result inextensive side effects. Extraction procedures applied to the analysis of their formulations are still limited to a few methodologies, despite the increasing numbers of confiscations of AASs. In this sense, the aims of this work were to evaluate the extraction of active ingredients from formulations of anabolic agents using solid-liquid or liquid-iquid, ultrasonic bath, ultrasonicprobe, and microwave-assisted extraction. The results indicated that the extraction procedures influenced the detected concentration of AASs, as the use of ultrasonic probe and microwave irradiation increased the overall extraction of anabolic agents compared with solid-liquid, liquid-liquid, and ultrasonic bath. Regarding oxymetholone, for instance, the microwave-assisted extraction and ultrasonic probe extracted, respectively, 37.46 ± 1.36 and 35.69 ± 0.98 mg/tablet, while solid-liquid extracted 29.63 ± 0.40 mg/tablet of the activeingredient. Therefore, alternative methods such as microwave-assisted extraction or theultrasonic probe could be used for the analysis of formulations of AASs assisting with the identification of illicit and toxic components.


Asunto(s)
Anabolizantes/análisis , Fraccionamiento Químico/métodos , Congéneres de la Testosterona/análisis , Doping en los Deportes , Extracción Líquido-Líquido , Microondas , Extracción en Fase Sólida , Comprimidos , Ultrasonido/métodos
7.
Forensic Sci Int ; 297: 198-203, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30826603

RESUMEN

INTRODUCTION: The improvement of aesthetic properties of dental materials has hampered the work of forensic experts in cases of identification. Even in dental practice, the identification of the margins of restorations has become a challenge. OBJECTIVE: To establish protocols to improve the visual contrast between teeth and composites using dyes. METHOD: Anterior and premolar human teeth were chosen (n = 40) and class V cavities were made in the lingual/palatal and buccal surfaces. Ten commercially available dyes were dissolved in distilled water. Three protocols were proposed using phosphoric acid (Gphos) and hydrofluoric acid (Ghydro) for 60 s followed by application of the dye for 20 s. The control group (Gcontrol) was acid free, i.e. only distilled water was applied. Data was analysed using Kruskal-Wallis and Dunn´s tests. RESULTS: Analyses showed that darker dyes, such as crystal violet, methylene blue, malachite green and neutral red, had better results (p < 0.001). The composite brand did not influence the results (p > 0.05). Both Gphos and Ghydro were effective in discriminating restorations when compared to Gcontrol (p > 0.001). No differences were detected between Gphos and Ghydro protocols (p > 0.05). In Gphos, the enamel surface was stained leaving the restoration without pigmentation. Oppositely, in Ghydro the composite filling was coloured, but not the enamel. In Gcontrol, both enamel and restoration were stained indistinctively. CONCLUSION: Tooth etching with either phosphoric or hydrofluoric acids was suitable to discriminate the presence of aesthetic dental fillings.


Asunto(s)
Restauración Dental Permanente , Odontología Forense/métodos , Coloración y Etiquetado , Colorantes , Resinas Compuestas , Grabado Dental , Humanos , Ácido Fluorhídrico , Ácidos Fosfóricos
8.
Front Microbiol ; 9: 412, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29568291

RESUMEN

Background: Macroalgae are sources of bioactive compounds due to the large number of secondary metabolites they synthesize. The Antarctica region is characterized by extreme weather conditions and abundant aggregations of macroalgae. However, current knowledge on their biodiversity and their potential for bio-prospecting is still fledging. This study evaluates the antimicrobial and cytotoxic activity of different extracts of four macroalgae (Cystosphaera jacquinotii, Iridaea cordata, Himantothallus grandifolius, and Pyropia endiviifolia) from the Antarctic region against cancer and non-cancer cell lines. Methods: The antimicrobial activity of macroalgae was evaluated by the broth microdilution method. Extracts were assessed against Staphylococcus aureus ATCC 19095, Enterococcus faecalis ATCC 4083, Escherichia coli ATCC29214, Pseudomonas aeruginosa ATCC 9027, Candida albicans ATCC 62342, and the clinical isolates from the human oral cavity, namely, C. albicans (3), C. parapsilosis, C. glabrata, C. lipolytica, and C. famata. Cytotoxicity against human epidermoid carcinoma (A-431) and mouse embryonic fibroblast (NIH/3T3) cell lines was evaluated with MTT colorimetric assay. Results: An ethyl acetate extract of H. grandifolius showed noticeable antifungal activity against all fungal strains tested, including fluconazole-resistant samples. Cytotoxicity investigation with a cancer cell line revealed that the ethyl acetate extract of I. cordata was highly cytotoxic against A-431 cancer cell line, increasing the inhibitory ratio to 91.1 and 95.6% after 24 and 48 h exposure, respectively, for a concentration of 500 µg mL-1. Most of the algal extracts tested showed little or no cytotoxicity against fibroblasts. Conclusion: Data suggest that macroalgae extracts from Antarctica may represent a source of therapeutic agents. HIGHLIGHTS Different macroalgae samples from Antarctica were collected and the lyophilized biomass of each macroalgae was extracted sequentially with different solventsThe antimicrobial and anticancer potential of macroalgae extracts were evaluatedEthyl acetate extract of H. grandifolius showed noticeable antifungal activity against all the fungal strains tested, including fluconazole-resistant samplesEthyl acetate extract of I. cordata was highly cytotoxic against the A-431 cancer cell lineMost of the algal extracts tested showed little or no cytotoxicity against normal cell lines.

9.
Pharmacol Rep ; 69(1): 156-161, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27923159

RESUMEN

BACKGROUND: A variety of chalcones have demonstrated cytotoxic activity toward several cancer cell lines. This study aimed to investigate the cytotoxicity of four chalcones derivatives of 2-acetylthiophene in human breast cancer cell lines. METHODS: MCF-7 and MDA-MB-231 cells were treated with synthesized chalcones and the cytotoxicity was evaluated by tetrazolium dye (MTT), live/dead, and DAPI assays. RESULTS: Chalcones significantly decreased MCF-7 and MDA-MB-231 cells viability in vitro in a dose dependent manner. After 48h treatment, the IC50 values ranging from 5.52 to 34.23µM. Chalcone 3c displayed the highest cytotoxic activity from all the tested compounds. Cytotoxic effects of compounds were confirmed in the live/dead assay. In addition, DAPI staining revealed that these compounds induce death by apoptosis. CONCLUSION: The data speculate that chalcone derivatives of 2-acetylthiophene may represent a source of therapeutic agents for human breast cancer.


Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias de la Mama , Chalcona/farmacología , Tiofenos/farmacología , Apoptosis/fisiología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Chalcona/química , Chalcona/uso terapéutico , Relación Dosis-Respuesta a Droga , Femenino , Inhibidores de Crecimiento/farmacología , Humanos , Células MCF-7 , Tiofenos/química , Tiofenos/uso terapéutico
10.
J Pharm Pharmacol ; 66(5): 733-46, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24372555

RESUMEN

OBJECTIVES: Eugenol, obtained from clove oil (Eugenia caryophyllata), possess several biological activities. It is anti-inflammatory, analgesic, anaesthesic, antipyretic, antiplatelet, anti-anaphylactic, anticonvulsant, anti-oxidant, antibacterial, antidepressant, antifungal and antiviral. The anti-oxidant activity of eugenol have already been proven. From this perspective testing, a series of planned structural derivatives of eugenol were screened to perform structural optimization and consequent increase of the potency of these biological activities. METHODS: In an attempt to increase structural variability, 16 compounds were synthesized by acylation and alkylation of the phenolic hydroxyl group. Anti-oxidant activity capacity was based on the capture of DPPH radical (2,2-diphenyl-1-picryl-hydrazyl), ABTS radical 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), measure of TBARS (thiobarbituric acid-reactive species), total sulfhydryl and carbonyl content (eugenol derivatives final concentrations range from 50 to 200 µm). KEY FINDINGS: Four derivatives presented an efficient concentration to decrease 50% of the DPPH radical (EC50 ) < 100 µm, which has a good potential as a free-radical scavenger. Three of these compounds also showed reduction of ABTS radical. Eugenol derivatives presenting alkyl or aryl (alkylic or arylic) groups substituting hydroxyl 1 of eugenol were effective in reducing lipid peroxidation, protein oxidative damage by carbonyl formation and increase total thiol content in cerebral cortex homogenates. In liver, the eugenol derivatives evaluated had no effect. CONCLUSIONS: Our results suggest that these molecules are promising anti-oxidants agents.


Asunto(s)
Antioxidantes/farmacología , Eugenol/farmacología , Peroxidación de Lípido/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Carbonilación Proteica/efectos de los fármacos , Syzygium/química , Animales , Benzotiazoles/metabolismo , Compuestos de Bifenilo/metabolismo , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Eugenol/análogos & derivados , Hígado/efectos de los fármacos , Masculino , Picratos/metabolismo , Ratas Wistar , Compuestos de Sulfhidrilo/metabolismo , Ácidos Sulfónicos/metabolismo
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