Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros

Base de dados
País como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Molecules ; 25(21)2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33126733

RESUMO

Lavender flowers were used in this study as a source of phytochemicals as naturally occurring antioxidants. Two different extraction techniques were applied, such as ultrasound-assisted (UAE) and supercritical fluids (SCE) methods. The comparative evaluation of the phytochemicals profile evidenced a higher content of chlorophyll a and b of 5.22 ± 0.12 mg/g dry weight (D.W.) and 2.95 ± 0.16 mg/g D.W, whereas the carotenoids content was 18.24 ± 0.04 mg/g D.W. in the SCE extract. Seven main compounds were found in both extracts: ß-linalool, eucalyptol, linalool acetate, ß-trans-ocimene, and limonene in SCE and linalool acetate, ß-linalool, 6-methyl-2-(2-oxiranyl)-5-hepten-2-ol, linalool oxide, lavandulyl acetate and camphor in UAE. The (n-3) acids had a higher contribution in SCE. The extracts were microencapsulated in different combinations of wall materials based on polysaccharides and milk proteins. The four variants showed different phytochemical and morphological profiles, with a better encapsulating efficiency for proteins (up to 98%), but with a higher content of encapsulated carotenoids for polysaccharides, the latter showing remarkable antimicrobial activity against selected microorganisms. Carboxymethyl cellulose and whey proteins led to a double encapsulation of lipophilic compounds. The powders were tested in two food matrices as ingredients, with multiple targeted functions, such as flavoring, antimicrobial, antioxidant activity that can successfully replace synthetic additives.


Assuntos
Alimentos , Lavandula/química , Compostos Fitoquímicos/farmacologia , Cápsulas , Flores/química , Compostos Fitoquímicos/química
2.
J Occup Environ Hyg ; 15(8): 580-587, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29708861

RESUMO

Walk-through surveys were carried out for bakeries in this study to determine the environmental characteristics of bakeries in Taiwan. Questionnaires were administrated to discover whether job-related asthma-like symptoms occurred among workers. Air sampling and analysis were also performed. The results show that the levels of inhalable flour dust ranged from 0.01-0.83 mg m-3 with an average of 0.27 mg m-3. Among the samples collected, 23% of them had concentrations higher than the ACGIH TLV-TWA (0.5 mg m-3), which indicated that inhalable flour dust was an important air pollutant for bakery workers in Taiwan. Airborne chemicals such as diacetyl, acetoin, 2,3-pentanedione, 2,3-hexanedione, 2,3-heptanedione, furfural, and acetaldehyde were also found in various levels in this study. The concentrations of acetaldehyde measured in these bakeries were 37-83 times higher than what have been reported from other studies for residential areas and Chinese restaurants. In addition, the concentrations of total VOCs in the working areas of the bakeries were over 21 times higher than the levels determined in the non-working areas. Based on our results, there appears to be a need to improve the air quality of the working environments of bakeries in Taiwan.


Assuntos
Farinha/análise , Manipulação de Alimentos , Exposição Ocupacional/análise , Acetaldeído/análise , Poluentes Ocupacionais do Ar/análise , Asma/epidemiologia , Poeira/análise , Aromatizantes/análise , Humanos , Doenças Profissionais/epidemiologia , Inquéritos e Questionários , Taiwan , Compostos Orgânicos Voláteis/análise
3.
Nutr Metab (Lond) ; 17: 12, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32021640

RESUMO

BACKGROUND: Diabetic patients are highly vulnerable to hypoxic injury, which is associated with hypoxia induced BNIP3 expression that subsequently activate apoptosis. Our previous research show that Tetramethylpyrazine (TMP), a food flavoring agent, represses the hypoxia induced BNIP3 expression attenuate myocardial apoptosis. In this study, we evaluate the effect of TMP to provide protection against hypoxia aggravated high-glucose associated cellular apoptosis. METHODS: The cytoprotective effect of TMP against high glucose induced cellular damages was determined on embryo derived H9c2 cardiomyoblast cells that were subjected to 5% hypoxia for 24 h and subjected to different duration of 33 mM high glucose challenge. Further, the involvement of HIF-1α and BNIP3 in cellular damage and the mechanism of protection of TMP were determined by overexpression and silencing HIF-1α and BNIP3 protein expression. RESULTS: The results show that hypoxic effects on cell viability aggravates with high glucose challenge and this augmentative effect is mediated through BNIP3 in H9c2 cardiomyoblast cells. However, TMP administration effectively reversed the augmented HIF-1α levels and BNIP3 elevation. TMP improved the survival of H9c2 cells and effectively suppressed apoptosis in H9c2 cells. Further comparison on the effects of TMP on H9c2 cells challenged with high glucose and those challenged with hypoxia show that TMP precisely regulated the hypoxic intensified apoptotic effects in high-glucose condition. CONCLUSION: The results clearly show that flavoring agent-TMP attenuates cytotoxicity amplified by hypoxia challenge in high glucose condition by destabilizing HIF-1α.

4.
Foods ; 9(7)2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32640536

RESUMO

Qualitative and semi-quantitative analysis of organosulfides extracted from oil obtained by steam distillation of yellow onions was performed by gas chromatography-mass spectrometry (GC-MS). The extraction efficiency of organosulfides from onion oil was evaluated across four solvents: dichloromethane; diethyl ether; n-pentane; and hexanes. Analysis of solvent extracted organosulfides by GC-MS provided qualitative results that support the use of dichloromethane over other solvents based on identification of 27 organosulfides from the dichloromethane extract as compared to 10 from diethyl ether; 19 from n-pentane; and 17 from hexanes. Semi-quantitative evaluation of organosulfides present in the dichloromethane extract was performed using diallyl disulfide as the internal reference standard. Three organosulfides were detected in the extract at ≥5 mg/kg; 18 organosulfides between 3-5 mg/kg; and six organosulfides at <3 mg/kg. The E/Z isomers of 1-propenyl propyl trisulfide were among the most prevalent components extracted from the onion oil across all solvents; and 3,6-diethyl-1,2,4,5-tetrathiane was among the most abundant organosulfides in all solvents except hexanes. The method described here for the extraction of organosulfides from steam distilled onion oil surveys common solvents to arrive at a qualitative and semi-quantitative method of analysis for agricultural products involving onions; onion oil; and secondary metabolites of Allium spp.

5.
Food Chem ; 313: 126136, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31927209

RESUMO

The adulteration of rice using synthetic aromatic flavorings to fraudulently imitate commercially valuable fragrant rice varieties has attracted extensive attention from regulatory authorities around the world. In order to get convincing evidence of adulteration, appropriate scientific analytical methods need to be developed. In this study, a simple and efficient headspace solid-phase microextraction (HS SPME) technique coupled with gas chromatography mass spectrometry using selected ion monitoring (GC-MS-SIM) for the determination of four food flavoring compounds which are possibly used as adulterants is proposed. The HS SPME operating under optimized conditions increased the selectivity and sensitivity of the analysis by eliminating matrix interferences. The method presented adequate precision and linearity with limits of detection ranging from 0.5 to 10 ng/mL. This HS SPME/GC-MS-SIM method is directly applicable to the analysis of volatiles in rice and has the advantages of minimal pretreatment. It was applied successfully to the analysis of six rice flavoring essences, ten fragrant rice and four artificially scented rice samples.


Assuntos
Aromatizantes/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Oryza/química , Microextração em Fase Sólida/métodos , Análise de Alimentos/métodos , Pirazinas/análise , Piridinas/análise , Reprodutibilidade dos Testes , Tiazóis/análise
6.
J Agric Food Chem ; 66(10): 2480-2484, 2018 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-28682070

RESUMO

Thummong ( Litsea petiolata Hook. f.) is a tree native to southern Thailand. The leaves of this tree are highly aromatic and used to flavor Thai dishes in place of the traditional water beetle Mangdana ( Lethocerus indicus) for religious and cultural reasons. Total and aroma-active volatiles from both flavoring materials were compared using gas chromatography-olfactory (GC-O) and gas chromatography-mass spectrometry (GC-MS). The volatiles from Thummong leaves and the Mangdana water beetle were collected and concentrated using headspace solid-phase microextraction. A total of 23 and 25 aroma-active volatiles were identified in Thummong leaves and Mangdana, respectively. The major aroma-active volatiles in Thummong leaves consisted of 7 aldehydes, 5 ketones, and 3 esters. In contrast, the aroma-active volatiles in the water beetle consisted of 11 aldehydes, 3 esters, and 2 ketones. Both had ( E)-2-nonenal as the most intense aroma-active volatile. The water beetle character impact volatile ( E)-2-hexenyl acetate was absent in the leaves, but its aroma character was mimicked by 11-dodecen-2-one in the leaves, which was absent in the beetle. In addition, a commercial Mangdana flavoring was examined using GC-O and GC-MS and found to contain only a single aroma-active volatile, hexyl acetate. All three flavoring sources exhibited similar aroma characteristics but were produced from profoundly different aroma-active volatiles.


Assuntos
Besouros/química , Aromatizantes/química , Litsea/química , Compostos Orgânicos Voláteis/química , Animais , Culinária , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Folhas de Planta/química , Paladar , Tailândia
7.
Int J Dev Neurosci ; 33: 98-105, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24374255

RESUMO

Physical exercise and excessive consumption of monosodium glutamate (MSG) can affect the morphological and electrophysiological organization of the brain during development. However, the interaction of both factors remains unclear. We analyzed the effect of this interaction on the excitability-related phenomenon known as cortical spreading depression (CSD) and the microglial reaction expressed as Iba1-immunolabeled cells in the rat motor cortex. MSG (2g/kg or 4g/kg) was administered every other day during the first 14 postnatal days. Treadmill exercise started at 21-23 days of life and lasted 3 weeks, 5 days/week, for 30min/day. At 45-60 days, CSD was recorded for 4h at two cortical points and the CSD parameters (velocity, amplitude, and duration of the negative potential change) calculated. Confirming previous observations, exercised rats presented with lower CSD velocities (3.29±0.18mm/min) than the sedentary group (3.80±0.18mm/min; P<0.05). MSG increased CSD velocities in the exercised rats compared to saline-treated and exercised animals in a dose-dependent manner (3.49±0.19, 4.05±0.18, and 3.27±0.26 for 2g/kg MSG, 4g/kg MSG, and saline, respectively; P<0.05). The amplitude (ranging from 14.3±5.9 to 18.7±6.2mV) and duration (46.7±11.1 to 60.5±11.6s) of the negative slow potential shift of the CSD were similar in all groups. Both exercise and MSG treatment increased Iba1 immunolabeling. The results confirm that physical exercise decelerates CSD propagation. However, it does not impede the CSD-accelerating action of MSG. These effects were accompanied by a cortical microglia reaction. Therefore, the data suggest that treadmill exercise early in life can influence the development of cortical electrical activity.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Córtex Cerebral , Depressão Alastrante da Atividade Elétrica Cortical/efeitos dos fármacos , Proteínas dos Microfilamentos/metabolismo , Condicionamento Físico Animal , Glutamato de Sódio/farmacologia , Fatores Etários , Análise de Variância , Animais , Animais Recém-Nascidos , Peso Corporal/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Córtex Cerebral/fisiologia , Eletroencefalografia , Teste de Esforço , Masculino , Microglia/efeitos dos fármacos , Microglia/metabolismo , Ratos , Ratos Wistar
8.
Life Sci ; 93(9-11): 388-92, 2013 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-23871986

RESUMO

AIMS: Monosodium glutamate (MSG) is a neuroexcitatory amino acid used in human food to enhance flavor. MSG can affect the morphological and electrophysiological organization of the brain. This effect is more severe during brain development. Here, we investigated the electrophysiological and morphological effects of MSG in the developing rat brain by characterizing changes in the excitability-related phenomenon of cortical spreading depression (CSD) and microglial reaction. MAIN METHODS: From postnatal days 1-14, Wistar rat pups received 2 or 4 g/kg MSG (groups MSG-2 and MSG-4, respectively; n=9 in each group), saline (n=10) or no treatment (naïve group; n=5) every other day. At 45-60 days, CSD was recorded on two cortical points for 4h. The CSD parameters velocity, and amplitude and duration of the negative potential change were calculated. Fixative-perfused brain sections were immunolabeled with anti-IBA-1 antibodies to identify and quantify cortical microglia. KEY FINDINGS: MSG-4 rats presented significantly higher velocities (4.59 ± 0.34 mm/min) than the controls (saline, 3.84 ± 0.20mm/min; naïve, 3.71 ± 0.8mm/min) and MSG-2 group (3.75 ± 0.10mm/min). The amplitude (8.8 ± 2.2 to 11.2 ± 1.9 mV) and duration (58.2 ± 7.1 to 73.6 ± 6.0s) of the negative slow potential shift was similar in all groups. MSG-treatment dose-dependently increased the microglial immunolabeling. SIGNIFICANCE: The results demonstrate a novel, dose-dependent action of MSG in the developing brain, characterized by acceleration of CSD and significant microglial reaction in the cerebral cortex. The CSD effect indicates that MSG can influence cortical excitability, during brain development, as evaluated by CSD acceleration. Data suggest caution when consuming MSG, especially in developing organisms.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Depressão Alastrante da Atividade Elétrica Cortical/efeitos dos fármacos , Aditivos Alimentares/toxicidade , Microglia/efeitos dos fármacos , Glutamato de Sódio/toxicidade , Animais , Animais Recém-Nascidos , Proteínas de Ligação ao Cálcio/imunologia , Córtex Cerebral/crescimento & desenvolvimento , Relação Dose-Resposta a Droga , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Aditivos Alimentares/administração & dosagem , Masculino , Proteínas dos Microfilamentos/imunologia , Microglia/metabolismo , Ratos , Ratos Wistar , Glutamato de Sódio/administração & dosagem , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa