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1.
J Agric Food Chem ; 71(5): 2616-2627, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36700632

RESUMO

The measurement of aromatic maturity during grape ripening provides very important information for determining the harvest date, particularly in white cultivars. However, there are currently no tools that allow this measurement to be carried out in a noninvasive and rapid way. For this reason, in the present work, we have studied the use of hyperspectral imaging (HSI)) to estimate the aromatic composition of Vitis vinifera L. Tempranillo Blanco berries during ripening. A total of 236 spectra in the VIS+short wave near-infrared (VIS+SW-NIR) range (400-1000 nm) of intact berries were acquired contactless under laboratory conditions. As gold standard values, a total of 20 volatile compounds were quantified by gas chromatography-mass spectrometry (GC-MS), and the concentration of total soluble solids (TSS) was measured by refractometry. Calibration, cross-validation, and prediction models were built using partial least squares (PLS). Values of RCV2 ≥ 0.70 were obtained for α-terpineol, p-cymene, ß-damascenone, ß-ionone, benzaldehyde, benzyl alcohol, hexanal, citral, linalool, 2-phenylethanol, octanoic acid, nonanoic acid, 2-hexenal, 2-hexen-1-ol, (Z)-3-hexen-1-ol, total C13 norisoprenoids, total C6 compounds, total positive compounds (i.e., the sum of all families except C6 compounds), total benzenoids, and total soluble solids (TSS). Therefore, it can be affirmed that HSI in the VIS + SW-NIR range could be a good tool to estimate the aromatic composition of Tempranillo Blanco grape berries in a contactless, fast, and nondestructive way.


Assuntos
Vitis , Compostos Orgânicos Voláteis , Vinho , Humanos , Vitis/química , Odorantes/análise , Frutas/química , Imageamento Hiperespectral , Álcool Benzílico/análise , Compostos Orgânicos Voláteis/análise , Vinho/análise
2.
Clin Rev Allergy Immunol ; 59(1): 101-108, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32323145

RESUMO

Contact dermatitis linked to cosmetic products is a very common reason for visits to the dermatologist, and in more than half the cases, it is due to an allergic reaction. Fragrances are most often the culprit. The aim of the study was to describe the common fragrance allergens in different categories of cosmetic products available on the European market. We wanted to assess the influence of cosmetic type and distribution channel on the presence of fragrance allergens. There are the allergens whose concentration exceeds 0.001% in leave-on products and 0.01% in rinse-off products. A total of 2044 commercial hygiene, care, and makeup cosmetic products were analyzed to specifically study regulated fragrance allergens. The influence that the product category and its distribution channel (retail stores and specialized stores such as beauty institutes or hairdressers and pharmacy) have on the prevalence of these allergens was evaluated. The Kruskal-Wallis test has been used for statistical data analysis. There is a wide range of fragrance allergens, the most common being limonene (found in about 30% of products tested), linalool (just over a quarter of the products tested), and benzyl alcohol (approximately 16% of the products tested). The average number of allergens found and their nature varies depending on the type of product in question (maximum number for shampoos and oral care with about 70 allergens and minimum number for nail polish and makeup for eyes with fewer than 10 allergens). In the area of hygiene, deodorants and oral hygiene products are particularly noteworthy, the former for their significantly high number of allergens and the latter for their low number. There is also a significant difference between the number of allergens found in eye makeup and foundations. Our results indicate that the number of regulated fragrance allergens is particularly influenced by the type of products.


Assuntos
Alérgenos/análise , Cosméticos/química , Dermatite Alérgica de Contato/imunologia , Perfumes/química , Monoterpenos Acíclicos/análise , Monoterpenos Acíclicos/imunologia , Animais , Álcool Benzílico/análise , Álcool Benzílico/imunologia , Feminino , Humanos , Limoneno/análise , Limoneno/imunologia , Masculino , Odorantes
3.
J Agric Food Chem ; 68(8): 2485-2492, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32049524

RESUMO

Employing isotope incubation studies, the biosynthetic pathway leading to a series of benzylic derivatives was elucidated in the fermentation broth of the edible mushroom Ischnoderma resinosum (P. Karst). Twenty-six hydroxy- and methoxy- benzylic derivatives were screened by gas chromatography-mass spectrometry (GC-MS) of which 13 were detected in the culture media. Results from the isotope incubation studies showed the transformation of both benzyl alcohol and benzoic acid into benzaldehyde. Benzaldehyde was then converted into 4-methoxybenzaldehyde via hydroxylation and subsequent methylation of the 4-C position. The resulting 4-methoxybenzaldehyde was then hydroxylated in the 3-C position followed by methylation into 3,4-dimethoxybenzaldehyde. Based on these findings, a novel metabolic scheme for the biosynthesis of benzylic derivatives in I. resinosum was proposed. The knowledge of the biosynthetic pathway was utilized to produce 4-hydroxy-3-methoxybenzaldehyde (vanillin) from 4-hydroxy-3-methoxybenzoic acid (vanillic acid). This is the first report to elucidate the biosynthetic pathway of benzyl derivatives and production of vanillin from I. resinosum.


Assuntos
Benzaldeídos/metabolismo , Polyporales/metabolismo , Benzaldeídos/análise , Ácido Benzoico/análise , Ácido Benzoico/metabolismo , Álcool Benzílico/análise , Álcool Benzílico/metabolismo , Biotransformação , Meios de Cultura/química , Meios de Cultura/metabolismo , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Polyporales/química , Polyporales/genética , Ácido Vanílico/análise , Ácido Vanílico/metabolismo
4.
J Oleo Sci ; 67(7): 813-822, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29877221

RESUMO

Volatile compounds and quality changes of bitter apricot (Armeniaca sibirica L.) kernel oil (AKO) with different roasting conditions were determined. Bitter apricot kernels were roasted at 120, 130, 140 and 150°C for 15 min. Unroasted bitter apricot kernel oil was used as the control. Quality indicators included color, acid value and peroxide value, fatty acids, total phenols and oxidative stability. Peroxide values of the tested oils were 0.46-0.82 meq/kg, acid values were 0.60-1.40 mg KOH/g, and total phenol contents were 54.1-71.5 µg GAE/g. Oleic acid was the major fatty acid, followed by linoleic, palmitic, stearic and palmitoleic acids. Roasting increased the oxidative stability of bitter AKO. Volatile compounds were tentatively identified and semi-quantified. Among the 53 volatiles identified, benzaldehyde and benzyl alcohol were the major components. These two aroma compounds increased significantly during roasting and contributed sweet and almond flavors. Pyrazines were also prevalent and significantly increased with roasting. Sensory evaluation showed that roasted, nutty, sweet and oily aromas increased as roasting temperature increased.Practical applications: Bitter apricot kernels cannot be consumed directly, thus it is potentially beneficial to find uses for them, especially in China where bitter apricot processing is a significant industry. Roasted bitter AKO with a pleasant aroma could be prepared and might find use as an edible oil. The roasting process gave the bitter AKO a pleasant flavor. This study provided preliminary information on production parameters and potential quality control parameters.


Assuntos
Culinária , Temperatura Alta , Óleos de Plantas/química , Prunus armeniaca/química , Sementes/química , Benzaldeídos/análise , Álcool Benzílico/análise , Fenômenos Químicos , Ácidos Graxos , Qualidade dos Alimentos , Peróxidos/análise , Fenóis/análise , Pirazinas/análise
5.
Artigo em Inglês | MEDLINE | ID: mdl-27327260

RESUMO

Five different chemometric methods were developed for the simultaneous determination of betamethasone dipropionate (BMD), clotrimazole (CT) and benzyl alcohol (BA) in their combined dosage form (Lotriderm® cream). The applied methods included three full spectrum based chemometric techniques; namely principal component regression (PCR), Partial Least Squares (PLS) and Artificial Neural Networks (ANN), while the other two methods were PLS and ANN preceded by genetic algorithm procedure (GA-PLS and GA-ANN) as a wavelength selection procedure. A multilevel multifactor experimental design was adopted for proper construction of the models. A validation set composed of 12 mixtures containing different ratios of the three analytes was used to evaluate the predictive power of the suggested models. All the proposed methods except ANN, were successfully applied for the analysis of their pharmaceutical formulation (Lotriderm® cream). Results demonstrated the efficiency of the four methods as quantitative tool for analysis of the three analytes without prior separation procedures and without any interference from the co-formulated excipient. Additionally, the work highlighted the effect of GA on increasing the predictive power of PLS and ANN models.


Assuntos
Anestésicos Locais/análise , Anti-Infecciosos Locais/análise , Anti-Inflamatórios/análise , Álcool Benzílico/análise , Betametasona/análogos & derivados , Clotrimazol/análise , Algoritmos , Betametasona/análise , Calibragem , Combinação de Medicamentos , Análise dos Mínimos Quadrados , Redes Neurais de Computação , Análise de Componente Principal , Creme para a Pele/análise , Espectrofotometria/métodos
6.
Sci Rep ; 6: 26948, 2016 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-27244590

RESUMO

One of the major challenges in olfaction research is to relate the structural features of the odorants to different features of olfactory system. However, no relationship has been yet discovered between the structure of the olfactory stimulus, and the structure of respiratory signal. This study reveals the plasticity of human respiratory signal in relation to 'complex' olfactory stimulus (odorant). We demonstrated that fractal temporal structure of respiration dynamics shifts towards the properties of the odorants used. The results show for the first time that more structurally complex a monomolecular odorant will result in less fractal respiratory signal. On the other hand, odorant with higher entropy will result the respiratory signal with lower entropy. The capability observed in this research can be further investigated and applied for treatment of patients with different respiratory diseases.


Assuntos
Fractais , Odorantes/análise , Percepção Olfatória/fisiologia , Olfato/fisiologia , Adulto , Álcool Benzílico/análise , Álcool Benzílico/química , Entropia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pentanóis/análise , Pentanóis/química , Respiração , Relação Estrutura-Atividade , Succinatos/análise , Succinatos/química
7.
Chemosphere ; 148: 68-76, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26802265

RESUMO

Recently, sulfate radical ( [Formula: see text] ) based-advanced oxidation technologies (AOTs) have been attracted great attention in the remediation of contaminated soil and groundwater. In the present study, Co(2+) ions activated peroxymonosulfate (PMS) system was used to degrade 1, 1, 1-trichloro-2, 2'bis(p-chlorophenyl) ethane (DDT) in aqueous solutions. It was found that DDT was efficiently degraded in the PMS/Co(II) solutions within several hours, and the degradation efficiency of DDT was dependent on the concentrations of PMS and Co(II), and the optimum molar ratio of PMS and Co(II) was 50:1. The degradation kinetics of DDT were well described with pseudo-first-order equations over a range of temperature (10-40 °C), and the activation energy that was calculated with Arrhenius equation was 72.3 ± 2.6 kJ/mol. Electron paramagnetic resonance (EPR) and GC-MS techniques were applied to identify the intermediates and reactive species for DDT degradation. The results indicated that [Formula: see text] and OH were the main reactive species accounting for DDT degradation. Dichlorobenzophenone, 4-chlorobenzoic acid and benzylalcohol were the dominant intermediates for DDT degradation, and the likely degradation pathway of DDT was proposed on the basis of these identified products. Increasing pH inhibited the formation of [Formula: see text] and OH, and thus decreased the catalytic degradation of DDT. Cl(-) ion was found to significantly inhibit, while [Formula: see text] and dissolved oxygen had limited effects on DDT degradation.


Assuntos
Cobalto/química , DDT/análise , Peróxidos/química , Poluentes Químicos da Água/análise , Benzofenonas/análise , Álcool Benzílico/análise , Catálise , Clorobenzoatos/análise , DDT/química , Espectroscopia de Ressonância de Spin Eletrônica , Recuperação e Remediação Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Cinética , Modelos Teóricos , Oxirredução , Soluções , Poluentes Químicos da Água/química
8.
J Chromatogr A ; 1408: 108-17, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26162665

RESUMO

Partition coefficients of seven low molecular weight compounds were measured in multiple aqueous two-phase systems (ATPSs) formed by pairs of different polymers. The ionic composition of each ATPS was varied to include 0.01M sodium phosphate buffer (NaPB), pH 7.4 and 0.1M Na2SO4, 0.15M NaCl, and 0.15M NaClO4 all in 0.01M NaPB, pH 7.4. The differences between the solvent features of the coexisting phases in all the ATPSs were estimated from partitioning of a homologous series of dinitrophenylated-amino acids and by the solvatochromic method. The solute-specific coefficients for the compounds examined were determined by the multiple linear regression analysis using the modified linear solvation energy relationship equation. It is established that the solute specific coefficients characterizing different types of the solute-water interactions (dipole-dipole, dipole-ion, and H-bonding) for a given solute change in the presence of different salt additives in the solute specific manner. It is also found that these characteristics are linearly interrelated. It is suggested that there is a cooperativity between various types of solute-water interactions governed by the solute structure.


Assuntos
Dextranos/química , Polietilenoglicóis/química , Povidona/química , Aminoácidos/análise , Benzaldeídos/análise , Álcool Benzílico/análise , Cumarínicos/análise , Glucosídeos/análise , Modelos Lineares , Fenol/análise , Álcool Feniletílico/análise , Solventes/química , Água/química
9.
Ann Occup Hyg ; 58(7): 846-59, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24802252

RESUMO

UNLABELLED: A growing body of epidemiologic evidence suggests an association between exposure to cleaning products and respiratory dysfunction. Due to the lack of quantitative assessments of respiratory exposures to airborne irritants and sensitizers among professional cleaners, the culpable substances have yet to be identified. PURPOSE: Focusing on previously identified irritants, our aims were to determine (i) airborne concentrations of monoethanolamine (MEA), glycol ethers, and benzyl alcohol (BA) during different cleaning tasks performed by professional cleaning workers and assess their determinants; and (ii) air concentrations of formaldehyde, a known indoor air contaminant. METHODS: Personal air samples were collected in 12 cleaning companies, and analyzed by conventional methods. RESULTS: Nearly all air concentrations [MEA (n = 68), glycol ethers (n = 79), BA (n = 15), and formaldehyde (n = 45)] were far below (<1/10) of the corresponding Swiss occupational exposure limits (OEL), except for ethylene glycol mono-n-butyl ether (EGBE). For butoxypropanol and BA, no OELs exist. Although only detected once, EGBE air concentrations (n = 4) were high (49.48-58.72mg m(-3)), and close to the Swiss OEL (49mg m(-3)). When substances were not noted as present in safety data sheets of cleaning products used but were measured, air concentrations showed no presence of MEA, while the glycol ethers were often present, and formaldehyde was universally detected. Exposure to MEA was affected by its amount used (P = 0.036), and spraying (P = 0.000) and exposure to butoxypropanol was affected by spraying (P = 0.007) and cross-ventilation (P = 0.000). CONCLUSIONS: Professional cleaners were found to be exposed to multiple airborne irritants at low concentrations, thus these substances should be considered in investigations of respiratory dysfunctions in the cleaning industry; especially in specialized cleaning tasks such as intensive floor cleaning.


Assuntos
Álcool Benzílico/análise , Etanolamina/análise , Etilenoglicóis/análise , Exposição por Inalação/análise , Poluição do Ar em Ambientes Fechados/análise , Asma/induzido quimicamente , Álcool Benzílico/toxicidade , Vestuário , Etanolamina/toxicidade , Etilenoglicóis/toxicidade , Humanos , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional/análise , Projetos Piloto , Solventes/análise , Solventes/toxicidade , Ventilação
10.
Dermatitis ; 25(2): 51-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24603515

RESUMO

Information on the presence of European Directive fragrance (EUF) allergens in plants and foods is important for numerous reasons. If an individual is allergic to an EUF and is avoiding fragrance, it is possible that they may still be exposed to the allergen in a natural product. In addition, because many of these allergens are also found in foods, it is possible that ingestion of a food containing the allergen may induce systemic contact allergy. Finally, individuals with lip dermatitis may react to contact with foods that contain the allergen. In this article, we have used the data available to identify which plants and foods contain EUF. When available, concentrations of EUF in natural products are provided. The goal of this article is to narrow down the list of botanicals to avoid for specific EUF allergies.


Assuntos
Alérgenos , Produtos Biológicos/química , Alimentos , Perfumes/química , Plantas/química , Acroleína/análogos & derivados , Acroleína/análise , Monoterpenos Acíclicos , Alérgenos/análise , Anisóis/análise , Benzoatos/análise , Álcool Benzílico/análise , Cumarínicos/análise , Cicloexenos/análise , Eugenol/análogos & derivados , Eugenol/análise , União Europeia , Farneseno Álcool/análise , Aromatizantes/análise , Limoneno , Monoterpenos/análise , Propanóis/análise , Salicilatos/análise , Terpenos/análise
11.
J Chromatogr Sci ; 52(1): 88-94, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23324734

RESUMO

This paper reports the development of a method for simultaneously determining five preservatives in cosmetics, cleaning agents and pharmaceuticals by fast liquid chromatography. Methylisothiazolinone, methylchloroisothiazolinone, benzyl alcohol, sodium benzoate and methylparaben were separated on a Chromolith Fast Gradient reversed-phase 18e column using gradient elution with acetonitrile and a 0.1% aqueous solution of formic acid, with a run time of 3 min. The preparation of solid and liquid samples included ultrasonic extraction with methanol with recoveries ranging from 69 to 119%. The developed method was used to analyze samples of cosmetics (66 samples), cleaning agents (five samples) and pharmaceutical industry products (17 samples).


Assuntos
Cromatografia Líquida/métodos , Cosméticos/química , Detergentes/química , Preparações Farmacêuticas/química , Conservantes Farmacêuticos/análise , Álcool Benzílico/análise , Álcool Benzílico/química , Limite de Detecção , Modelos Lineares , Parabenos/análise , Parabenos/química , Conservantes Farmacêuticos/química , Reprodutibilidade dos Testes , Benzoato de Sódio/análise , Benzoato de Sódio/química , Tiazóis/análise , Tiazóis/química
12.
J Agric Food Chem ; 61(47): 11321-5, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24206364

RESUMO

A method for carbon isotope ratio (δ(13)C) analysis was developed for compound-specific isotope analysis of tea volatiles, and the values were compared with the δ(13)C value from bulk isotope analyses. The δ(13)C value of 2-phenylethanol liberated via enzymatic hydrolysis of the 2-phenylethyl ß-primeveroside standard was examined first. Isotope fractionations for 2-phenylethyl ß-primeveroside from preparative high-performance liquid chromatography (HPLC) were also analyzed. The enzymatic treatment and the preparative HPLC process did not cause carbon isotope fractionations, substantiating the strategies available for δ(13)C analysis of volatile compounds. On the basis of the gas chromatography-combustion-isotope ratio mass spectrometry data from 2-phenylethanol, it was possible to derive the conditions for enzyme treatment and preparative HPLC of the glycoconjugates of 2-phenylethanol, (Z)-3-hexenol, and benzyl alcohol isolated from green tea leaves. Larger variations in δ(13)C were found for individual volatile compounds compared with bulk analytical data from the leaves, indicating the potential to utilize this strategy in assigning the geographical origin of green tea.


Assuntos
Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Chá/química , Álcool Benzílico/análise , Camellia sinensis/química , Isótopos de Carbono , Cromatografia Líquida de Alta Pressão/métodos , Glicosídeos/análise , Hexanóis/análise , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/análise , Folhas de Planta/química
13.
Talanta ; 115: 665-74, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24054646

RESUMO

In the last years the habit of smoking waterpipes has spread worldwide, especially among young people and emerged as global health issue. Although research is now under way for no less than 40 years in the field of waterpipe smoking, in comparison to cigarette smoking there is still insufficient knowledge on the real composition and the toxicity of the smoke inhaled and the resulting levels of exposure against particular hazardous ingredients. In most cases for waterpipe smoking a highly flavored tobacco called "moassel" is used. However, the number, quantity and toxicity of the added flavorings are widely unknown. In this study the static headspace gas chromatography-mass spectrometry (SHS-GC-MS) was used to identify 79 volatile flavor compounds present in waterpipe tobacco. Among these eleven compounds were analyzed quantitatively. The results show that waterpipe tobacco contains high amounts of the fragrance benzyl alcohol as well as considerable levels of limonene, linalool and eugenol, all of which are known as being allergenic in human skin. The proposed SHS-GC-MS method has been validated and found to be accurate, simple and characterized by low limits of detection (LOD) in the range of 0.016 to 4.3 µg/g tobacco for benzaldehyde and benzyl alcohol, respectively. The identification and characterization of waterpipe tobacco ingredients indeed reveals crucial for the assessment of potential health risks that may be posed by these additives in smokers.


Assuntos
Álcool Benzílico/análise , Cicloexenos/análise , Eugenol/análise , Aromatizantes/análise , Monoterpenos/análise , Nicotiana/química , Fumar , Terpenos/análise , Monoterpenos Acíclicos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Limite de Detecção , Limoneno , Água
14.
J AOAC Int ; 95(4): 1069-73, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22970574

RESUMO

A new method for the simultaneous quantitation of 11 preservatives-imidazolidinyl urea, benzyl alcohol, dehydroacetic acid, sorbic acid, phenoxyethanol, benzoic acid, salicylic acid, and four parabens (methyl, ethyl, propyl, and butyl)-in cosmetics by micellar electrokinetic capillary chromatography was established and validated. The separation was performed using an uncoated fused-silica capillary (50 pm id x 60.2 cm, effective length 50 cm) with a running buffer consisting of 15 mmol/L sodium tetraborate, 60 mmol/L boric acid, and 100 mmol/L sodium dodecyl sulfate. A 1:10 dilution of the running buffer was used as the sample buffer to extract the cosmetic samples. The key factors, such as the concentration and pH of the running and sample buffers, which influence quantitative analysis of the above 11 preservatives in cosmetic samples, were investigated in detail. The linear ranges of the calibration curves for imidazolidinyl urea and the other 10 preservatives were 50-1000 and 10-200 mg/L, respectively. The correlation coefficients of the standard curves were all higher than 0.999. The recoveries at the concentrations studied ranged from 93.0 to 102.7%. RSDs were all less than 5%. The new method with simple sample pretreatment met the needs for routine analysis of the 11 preservatives in cosmetics.


Assuntos
Cosméticos/análise , Conservantes Farmacêuticos/análise , Ácido Benzoico/análise , Álcool Benzílico/análise , Soluções Tampão , Calibragem , Técnicas de Química Analítica , Cromatografia Capilar Eletrocinética Micelar/métodos , Etilenoglicóis/análise , Concentração de Íons de Hidrogênio , Micelas , Parabenos/análise , Pironas/análise , Padrões de Referência , Reprodutibilidade dos Testes , Ácido Salicílico/análise , Ácido Sórbico/análise , Ureia/análogos & derivados , Ureia/análise
15.
J Food Sci ; 77(10): C1030-5, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23009608

RESUMO

The aroma-active compounds in Chinese bayberry were identified using gas chromatography-olfactometry (GC-O) and GC-mass spectrometry techniques. The volatile compounds were extracted using Liquid-liquid extraction, solvent-assisted flavor evaporation and headspace solid-phase microextraction (HS-SPME), respectively. On the basis of odor intensity, the most important aroma compounds in Chinese bayberry samples were caryophyllene, menthol, 4-terpineol, linalool oxide, linalool, benzyl alcohol, α-methylbenzyl alcohol, ß-phenylethanol, 3-methylbutanoic acid and acetic acid, and so on. Moreover, HS-SPME technique was employed to investigate the aroma compounds among immature and mature waxberry fruits. The results showed that terpenes (for example, ß-caryophyllene) was predominant and its concentration represented over 89.9% of the overall compounds, and alcohols, aldehydes, ketones, esters, acids, and others were typically present in lesser amounts. Finally, principal component analysis revealed that there was also significant difference between immature and mature waxberry fruits.


Assuntos
Cromatografia Gasosa/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Myrica/química , Odorantes/análise , Compostos Orgânicos Voláteis/isolamento & purificação , Monoterpenos Acíclicos , Álcool Benzílico/análise , Álcoois Benzílicos/análise , Frutas/química , Extração Líquido-Líquido/métodos , Monoterpenos/análise , Álcool Feniletílico/análise , Sesquiterpenos Policíclicos , Sesquiterpenos/análise , Microextração em Fase Sólida/métodos , Solventes/química , Paladar
16.
Int J Pharm ; 426(1-2): 54-60, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22286017

RESUMO

We recently used micro attenuated total reflection infrared (ATR-IR) spectroscopy to conduct imaging analysis of ointments and evaluate the distributions of the active pharmaceutical ingredient (API) and excipients. An alclometasone dipropionate (ALC) ointment was used as a model product. Almeta, a brand-name product, had a domain with absorbance at 1656 cm(-1) attributable to the carbonyl group of ALC, the API. Absorbances at 1040 and 3300 cm(-1) were also noted in this domain, indicating the presence of the solubilizer, propylene glycol. Data also suggested the presence of benzyl alcohol in this domain. More detailed analysis showed the distribution of surfactants and other excipients in the base. Similar results were obtained for Vitra, a generic version of Almeta. Imaging analysis with micro ATR-IR confirmed that both ointments are liquid droplet dispersions with ALC dissolved in propylene glycol and dispersed in a base. However, minor differences in the ingredient distributions of the two ointments were detected and reflect differences in excipient concentrations and type, or manufacturing differences. In summary, we used micro ATR-IR for imaging analysis of an original ointment, Almeta, and its generic form Vitra, and established a method for visually evaluating the distributions of the API and excipients in these ointments.


Assuntos
Medicamentos Genéricos/análise , Excipientes/análise , Glucocorticoides/análise , Metilprednisolona/análogos & derivados , Espectrofotometria Infravermelho , Tecnologia Farmacêutica/métodos , Álcool Benzílico/análise , Química Farmacêutica , Composição de Medicamentos , Metilprednisolona/análise , Microscopia de Polarização , Microespectrofotometria , Pomadas , Propilenoglicol/análise , Reologia
17.
Acta Pol Pharm ; 68(4): 467-72, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21796928

RESUMO

The purpose of the study was to develop a simple, versatile HPLC method for the identification and quantification of praziquantel and ivermectin (in Equimax) or praziquantel and abamectin (in Abamitel Plus). A satisfactory separation was obtained using the Supelcosil LC-ABZ+ column in gradient system with a mobile phase A: acetonitrile / water in 40:60 ratio and phase B: acetonitrile. The UV detection was set at 245 nm. The correlation coefficient values (> or = 0,998) for all active substances confirmed that the calibration curves (peak area vs. concentration) are linear. The results of the quantification and the statistical evaluation confirmed that the method is accurate and precise. It can also be applied to confirm the identity of benzyl alcohol, methyl p-hydroxybenzoate and propyl p-hydroxybenzoate in Abamitel Plus formulation.


Assuntos
Antiparasitários/análise , Cromatografia Líquida de Alta Pressão , Ivermectina/análogos & derivados , Praziquantel/análise , Drogas Veterinárias/análise , Acetonitrilas/química , Álcool Benzílico/análise , Calibragem , Química Farmacêutica , Cromatografia Líquida de Alta Pressão/normas , Combinação de Medicamentos , Concentração de Íons de Hidrogênio , Ivermectina/análise , Parabenos/análise , Reprodutibilidade dos Testes , Solventes/química , Espectrofotometria Ultravioleta , Água/química
18.
Chemosphere ; 82(2): 237-43, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20947130

RESUMO

The chemical composition of the odors typical of fires has recently been deciphered. Basically the constituents are mixtures of acetophenone, benzyl alcohol, hydroxylated derivatives of benzaldehyde, methoxylated and/or alkylated phenols and naphthalene. This finding makes it possible to develop objective, practical analytic measurement methods for the burnt smell as a contribution to improving fire damage assessment and remediation monitoring. With the aid of an artificially produced burnt smell and a panel of testers the odor detection threshold of a test mixture was determined olfactometrically to 2 µg m⁻³. Using a defined burnt-smell atmosphere in a test chamber, analytical methods with active sampling, the adsorbents XAD 7 and TENAX TA, and GC/MS measurement were then optimized and tested with a view to being able to carry out sensitive quantitative measurement of burnt smells. A further practical method with particular application to the qualitative characterization of this odor is based on the use of a new SPME (solid-phase microextraction) field sampler with DVB/CAR/PDMS (divinylbenzene/Carboxen™/polydimethylsiloxane) fibers.


Assuntos
Poluentes Atmosféricos/química , Monitoramento Ambiental/métodos , Incêndios , Odorantes/análise , Acetofenonas/análise , Acetofenonas/química , Poluentes Atmosféricos/análise , Benzaldeídos/análise , Benzaldeídos/química , Álcool Benzílico/análise , Álcool Benzílico/química , Cromatografia Gasosa-Espectrometria de Massas , Modelos Químicos , Naftalenos/análise , Naftalenos/química , Microextração em Fase Sólida
19.
Anal Biochem ; 408(1): 147-56, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-20850409

RESUMO

A quantitative analysis of a recalled contaminated lot of heparin sodium injection U.S. Pharmacopeia (USP) was undertaken in response to the controversy regarding the exact nature of the contaminant involved in the heparin (HP) crisis. A mass balance analysis of the formulated drug product was performed. After freeze-drying, a 1-ml vial for injection afforded 54.8±0.3 mg of dry solids. The excipients, sodium chloride and residual benzyl alcohol, accounted for 11.4±0.5 and 0.9±0.5 mg, respectively. Active pharmaceutical ingredient (API) represented 41.5±1.0 mg, corresponding to 75.7 wt% of dry mass. Exhaustive treatment of API with specific enzymes, heparin lyases, and/or chondroitin lyases was used to close mass balance. HP represented 30.5±0.5 mg, corresponding to 73.5 wt% of the API. Dermatan sulfate (DS) impurity represented 1.7±0.3 mg, corresponding to 4.1 wt% of API. Contaminant, representing 9.3±0.1 mg corresponding to 22.4 wt% of API, was found in the contaminated formulated drug product. The recovery of contaminant was close to quantitative (95.6-100 wt%). A single contaminant was unambiguously identified as oversulfated chondroitin sulfate (OSCS).


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Eletroforese Capilar/métodos , Heparina/análise , Álcool Benzílico/análise , Condroitina Liases/metabolismo , Sulfatos de Condroitina/análise , Dermatan Sulfato/análise , Contaminação de Medicamentos , Heparina Liase/metabolismo , Cloreto de Sódio/análise
20.
Artigo em Alemão | MEDLINE | ID: mdl-20853095

RESUMO

The German Working Group on Indoor Air Guidelines of the Federal Environment Agency and the States' Health Authorities is issuing indoor air guide values to protect public health. For health evaluation of benzyl alcohol in indoor air valid inhalation studies are missing. Following subchronic oral exposure to 800 mg benzyl alcohol/kg body weight and day neurotoxicity was observed in rats. Accounting for data gaps by a factor of 2 and extrapolating to continuous exposure by applying a factor of 2 the lowest adverse effect level for chronic exposure (LAELchron) is assessed as 200 mg benzyl alcohol/kg b. w. and day. By applying an interspecies factor of 10, an intraspecies factor of 10, a path-to-path-extrapolation and a modifying factor of 2 referring to the special physiology of children (higher breathing rate compared to adults) a health hazard guide value (RW II) of 4 mg benzyl alcohol/m3 indoor air and a health precaution guide value (RW I) of 0.4 mg benzyl alcohol/m3 are derived.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Álcool Benzílico/análise , Saúde Pública , Administração Cutânea , Administração por Inalação , Administração Oral , Adulto , Poluentes Ocupacionais do Ar/análise , Poluentes Ocupacionais do Ar/toxicidade , Animais , Álcool Benzílico/toxicidade , Criança , Relação Dose-Resposta a Droga , Feminino , Alemanha , Guias como Assunto , Humanos , Recém-Nascido , Camundongos , Doenças do Sistema Nervoso/induzido quimicamente , Gravidez , Especificidade da Espécie , Níveis Máximos Permitidos , Adulto Jovem
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