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1.
J Pharm Biomed Anal ; 153: 29-36, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29459233

RESUMO

Several flavoring and sweetening agents added to excipient of pediatric syrups are not declared in the package leaflet. Therefore, the aim of this study was to develop a non-target, simple, and precise method for qualitative and quantitative evaluation of pediatric syrups using NMR spectroscopy combined with chemometrics. This approach allowed the identification of several added compounds as citric acid, cyclamate, ethanol, glycerol, propylene glycol, saccharin, sorbitol, fructose, glucose, and sucrose. Among the sugared syrups, sucrose was the main carbohydrate with approximately 59.1%, and for sweetened syrups, glycerol with 25.5%. The ethanol was found with highest concentration of 4.0%, approximately. In addition, some syrups presented both sugar and sweetener, which is inconsistent according to the purpose of the addition. Consequently, institutional structures of countries as Brazil that are in charge of public health should put additional compliance pressure on pharmaceutical companies to clearly declare in package leaflet the presence and exact amount of the main compounds (at least) existent in the pediatric excipients.


Assuntos
Excipientes/química , Preparações Farmacêuticas/química , Edulcorantes/química , Brasil , Rotulagem de Medicamentos/métodos , Estudos de Avaliação como Assunto , Humanos , Espectroscopia de Ressonância Magnética , Pediatria
2.
Talanta ; 180: 329-336, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29332819

RESUMO

The genus Ocimum (Labiatae) comprises 30 species found in tropical and subtropical regions of the planet, of which species O. basilicum L. and O. gratissimum are widely used in food and traditional medicine. Phytochemical studies on Ocimum have revealed a number of essential oil chemotypes, for example, eugenol, methyl chavicol, linalool, and methyl cinnamate. Since essential oils are commercially assessed according to their content, the aim of this study was to develop a simple and precise method for their qualitative and quantitative analysis using NMR spectroscopy combined with chemometrics. Seven essential oils from different species of Ocimum, an unknown sample, and a commercial sample were evaluated and the results compared to those from established and precise GC-MS and GC-FID methods. Chemometric evaluation from both 1H NMR and GC-MS data revealed three chemotypes: eugenol for O. gratissimum, O. micranthum, and O. tenuiflorum; estragole for O. basilicum, O. basilicum var. purpuracens, and O. selloi; and methyl cinnamate for O. americanum. The unknown and commercial species were classified as cinnamate and eugenol chemotypes, respectively. Despite the corroborating results, the chemometric analysis revealed the higher robustness (better adjustment) of the 1H NMR model compared to the GC-MS method in terms of certain statistical parameters. The 1H NMR method allows for the detection and quantification of organic compounds in a complex mixture without the need for certified standard compounds. Although GC-MS and GC-FID were able to detect five compounds not observed by NMR spectroscopy, the four most important metabolites (eugenol, estragole, methyl cinnamate, and eucalyptol) were more readily detected and quantified by 1H NMR.


Assuntos
Cromatografia Gasosa/métodos , Espectroscopia de Ressonância Magnética/métodos , Ocimum/química , Óleos Voláteis/análise , Óleos de Plantas/análise , Monoterpenos Acíclicos , Derivados de Alilbenzenos , Anisóis/análise , Cinamatos/análise , Cicloexanóis/análise , Eucaliptol , Eugenol/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Monoterpenos/análise
3.
Methods Mol Biol ; 1735: 365-379, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29380328

RESUMO

Nuclear magnetic resonance (NMR) spectroscopy in combination with chemometrics can be applied in the analysis of complex biological samples in many ways. For example, we can analyze lipids, elucidate their structures, determine their nutritional values, and determine their distribution in blood serum. As lipids are not soluble in water, they are transported in blood as lipid-rich self-assembled particles, divided into different density assemblies from high- to very-low-density lipoproteins (HDL to VLDL), or by combining with serum proteins, such as albumins (human serum albumins (HSA)). Therefore, serum lipids can be analyzed as they are using only a 1:1 (v/v) dilution with a buffer or deuterated water prior to analysis by applying 1H NMR or 1H NMR edited-by-diffusion techniques. Alternatively, lipids can be extracted from the serum using liquid partition equilibrium and then analyzed using liquid-state NMR techniques. Our chapter describes protocols that are used for extraction of blood serum lipids and their quantitative 1H NMR (1H qNMR) analysis in lipid extracts as well as 1H NMR edited by diffusion for direct blood serum lipid analysis.


Assuntos
Lipídeos/sangue , Espectroscopia de Ressonância Magnética , Metabolômica , Biomarcadores , Humanos , Espectroscopia de Ressonância Magnética/métodos , Metabolômica/métodos
4.
Data Brief ; 11: 136-146, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28224130

RESUMO

In this article the NMR data from chemical shifts, coupling constants, and structures of all the characterized compounds were provided, beyond a complementary PCA evaluation for the corresponding manuscript (E.G. Alves Filho, L.M.A. Silva, E.M. Teofilo, F.H. Larsen, E.S. de Brito, 2017) [3]. In addition, a complementary assessment from solid-state NMR data was provided. For further chemometric analysis, numerical matrices from the raw 1H NMR data were made available in Microsoft Excel workbook format (.xls).

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