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1.
Food Sci Nutr ; 8(2): 744-753, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32148784

RESUMO

Advantame is a novel sweetener, and 3-hydroxy-4-methoxy benzal acrolein is an important intermediate to synthesize the sweetener. The aim of this study was to evaluate a new low-cost method to purify 3-hydroxy-4-methoxy benzal acrolein, and the crude intermediate was used as raw material. The intermediate was purified using a low-pressure column chromatography with a C18 column, using a methanol-water (6:4, v/v) at a flow rate of 6.0 ml/min, and the loading amount of the crude intermediate in solution was 10.0 mg in total. A method for the analysis of 3-hydroxy-4-methoxy benzal acrolein was established using high-performance liquid chromatography (HPLC). This method was validated in terms of its linearity, repeatability, accuracy, detection limit, and quantitation limit. The calibration curves of 3-hydroxy-4-methoxy benzal acrolein were linear (r > .999) over a wide concentration range of 0.005-0.08 mg/ml, by comparing the ratio of signal to noise, and the detection limit was 5.0 ng/ml and the quantification limit was 15.0 ng/ml. Good repeatability was obtained (RSD < 2%, n = 6), and the recoveries calculated using mixed sample previously quantified ranged from 94.5% to 106.37%. As long as, this method has been successfully applied to the analysis of 3-hydroxy-4-methoxy benzal acrolein; therefore, the method can be put into practical use during the industrial synthesis and real-time detection of the intermediate.

2.
J Biochem Mol Toxicol ; 32(1)2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29140578

RESUMO

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that regulates a cluster of oxidative stress-inducible genes in cells. Here, we aimed to investigate whether trehalose (Tre) protects primary rat proximal tubular (rPT) cells against cadmium (Cd)-induced oxidative stress via Nrf2 antioxidant pathway. Data showed that Tre treatment inhibited Nrf2 nuclear translocation and restored the decline in Kelch-like ECH-associated protein 1 (Keap1) protein level in Cd-exposed rPT cells. Moreover, Cd-activated Nrf2 target genes, including phase II detoxifying enzymes, that is, NAD(P)H quinone oxidoreductase 1 and heme oxygenase-1, direct antioxidant proteins, that is, glutathione peroxidase, superoxide dismutase, catalase, and glutathione biosynthesis-related proteins, that is, glutamatecysteine ligase catalytic subunit, glutamate cysteine ligase modifier subunit, and glutathione reductase, were all downregulated by co-treatment with Tre. Collectively, these findings demonstrate that Tre treatment alleviates Cd-induced oxidative stress in rPT cells by inhibiting the Nrf2-Keap1 signaling pathway.


Assuntos
Cádmio/toxicidade , Proteína 1 Associada a ECH Semelhante a Kelch/antagonistas & inibidores , Túbulos Renais Proximais/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Trealose/metabolismo , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Cádmio/química , Intoxicação por Cádmio/dietoterapia , Intoxicação por Cádmio/metabolismo , Intoxicação por Cádmio/patologia , Intoxicação por Cádmio/prevenção & controle , Catalase/antagonistas & inibidores , Catalase/química , Catalase/metabolismo , Células Cultivadas , Suplementos Nutricionais , Regulação para Baixo , Glutationa Redutase/antagonistas & inibidores , Glutationa Redutase/química , Glutationa Redutase/metabolismo , Heme Oxigenase-1/antagonistas & inibidores , Heme Oxigenase-1/química , Heme Oxigenase-1/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/agonistas , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Túbulos Renais Proximais/citologia , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , NAD(P)H Desidrogenase (Quinona)/antagonistas & inibidores , NAD(P)H Desidrogenase (Quinona)/química , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Substâncias Protetoras/metabolismo , Substâncias Protetoras/uso terapêutico , Ratos , Superóxido Dismutase/antagonistas & inibidores , Superóxido Dismutase/química , Superóxido Dismutase/metabolismo , Trealose/uso terapêutico
3.
J Food Drug Anal ; 24(3): 602-609, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-28911567

RESUMO

Chemical composition, anti-inflammatory activity, and cytotoxicity of essential oils obtained from the aerial parts of Trachydium roylei were investigated in this study. The chemical composition of T. roylei essential oil was analyzed using gas chromatography mass spectrometry. Fifty-nine components, representing 98.87% of the oils, were characterized. The oils were predominated by aromatic compounds and monoterpene hydrocarbons, and the main components were myristicin (25.35%), ß-phellandrene (22.95%), elemicine (7.69%), isoelemicin (5.48%), and cedrol (5.26%). The anti-inflammatory activity of the oil in lipopolysaccharide-stimulated murine RAW 264.7 cells was evaluated. The oils downregulated the production of proinflammatory cytokines, including tumor necrosis factor-α, interleukin (IL)-1ß, and IL-6, and significantly increased the anti-inflammatory cytokine IL-10 levels. Results indicated that the oils effectively inhibited the secretion of nitric oxide and prostaglandin E2 in lipopolysaccharide-stimulated macrophages. Western blot analyses were performed to determine whether the inhibitory effects of the oils on proinflammatory mediators (nitric oxide and prostaglandin E2) were related to the modulation of inducible nitric oxide synthase and cyclooxygenase-2 expression. These findings suggest that T. roylei essential oils exert an anti-inflammatory effect by regulating the expression of inflammatory cytokines.


Assuntos
Apiaceae , Animais , Anti-Inflamatórios , Monoterpenos Cicloexânicos , Cicloexenos , Camundongos , Monoterpenos , Óleos Voláteis
4.
Food Chem ; 162: 99-103, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24874363

RESUMO

This paper was aimed at characterising the insoluble substances (IS) responsible for the turbidity of the extract and impurity of the resulting pectins. Results showed that the IS caused a significant increase in the turbidity of the extract. The IS had bi-pyramidal shapes under the SEM observation. The observed XRD peaks for the IS were similar to those of calcium oxalate dihydrate (COD). Moreover, the IS consisted of mainly oxalate and calcium. Results from the present study indicate the IS is COD. The influence of the IS on the purity of pectin was also studied. The presence of the IS in the pectins indicated the IS can precipitate with pectins during the alcohol precipitation, thereby contaminating the resulting pectins.


Assuntos
Beta vulgaris/química , Oxalato de Cálcio/química , Pectinas/química
5.
J Dairy Sci ; 96(5): 2826-31, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23498013

RESUMO

5-Hydroxymethyl-2-furaldehyde can undergo polymerization to form high-molecular weight molecules via the Maillard reaction during dairy thermal treatment. In this study, the effect of sulfite group on polymer formation, especially in inhibiting the formation of high-molecular weight polymers has been described. Results showed that the sulfite group significantly inhibited the increase of polymer molecular weight via prevention of the polymerization of 5-hydroxymethyl-2-furaldehyde. The formation of an intermolecular dimer based on the glucose molecule through Schiff base cyclization can lead to a competitive reaction with 1,2-enolization to reduce 5-hydroxymethyl-2-furaldehyde formation, which might be another factor in reducing the formation of high-molecular weight polymers.


Assuntos
Tecnologia de Alimentos/métodos , Furaldeído/análogos & derivados , Polímeros/metabolismo , Sulfitos/metabolismo , Animais , Furaldeído/metabolismo , Temperatura Alta , Espectroscopia de Ressonância Magnética , Reação de Maillard , Leite/metabolismo , Peso Molecular , Polímeros/química , Bases de Schiff/metabolismo , Espectrometria de Massas por Ionização por Electrospray
6.
Z Naturforsch C J Biosci ; 67(5-6): 282-90, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22888533

RESUMO

Antioxidant and antimicrobial activities of the essential oil and n-hexane (HEE), chloroform (CHE), ethyl acetate (EAE), and methanol (MEE) extracts, respectively, from the root of Saurauia lantsangensis Hu were investigated. The GC-MS analysis revealed 39 compounds representing 96.41% of the oil containing T-muurolol (13.85%), acetophenone (7.46%), alpha-cadinol (6.26%), methyl palmitate (5.36%), n-hexadecanoic acid (4.31%), torreyol (3.69%), and isospathulenol (3.48%) as major components. Antioxidant activities determined by three various testing systems, i.e., DPPH radical scavenging, superoxide anion radical scavenging, and reducing power assay, increased in the order: HEE < CHE < oil < MEE < EAE. CHE, EAE, MEE and oil exhibited a promising antimicrobial effect determined as the diameter of zones of inhibition (13.3-16.2, 16.5-20.4, 13.5-16.6, and 16.5-22.7 mm), respectively, along with their respective MIC values (500-1000, 125-500, 250-500, and 250-500 microg/ml) against Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli), Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus), and a yeast (Hansenula anomala).


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Ericaceae/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Anti-Infecciosos/isolamento & purificação , Antioxidantes/isolamento & purificação , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Extratos Vegetais/química
7.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 8): m1073-4, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22904740

RESUMO

The asymmetric unit of the title compound, [Ag(3)Yb(C(5)HN(2)O(4))(2)(H(2)O)(2)](n), contains three Ag(I) ions, one Yb(III) ion, two imidazole-4,5-dicarboxyl-ate ligands and two coordinating water mol-ecules. The Yb(III) atom is eight-coordinated, in a bicapped trigonal prismatic coordination geometry, by six O atoms from three imidazole-4,5-dicarboxyl-ate ligands and two coordinating water mol-ecules. The two-coordinated Ag(I) ions exhibit three types of coordination environments. One Ag(I) atom is bonded to two N atoms from two different imidazole-4,5-dicarboxyl-ate ligands. The other two Ag(I) atoms are each coordinated by one O atom and one N atom from two different imidazole-4,5-dicarboxyl-ate ligands. These metal coordination units are connected by bridging imidazole-4,5-dicarboxyl-ate ligands, generating a two-dimensional heterometallic layer. These layers are stacked along the a axis via O-H⋯O hydrogen-bonding inter-actions to generate a three-dimensional framework.

8.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 8): o2597, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22905020

RESUMO

The asymmetric unit of the title salt, C(6)H(8)N(+)·C(7)H(5)O(4) (-), contains two anilinium cations and two 3,4-dihy-droxy-benzoate anions. An intra-moleculer O-H⋯O hydrogen bond occurs in each anion. In the crystal, O-H⋯O and N-H⋯O hydrogen bonds link the cations and anions into a three-dimensional array. The structure is further consolidated by weak C-H⋯O inter-actions.

9.
Drug Chem Toxicol ; 35(2): 155-61, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21834671

RESUMO

Human copper/zinc superoxide dismutase from recombinant Pichia pastori (RH-Cu/Zn-SOD) was orally administered, via gavage, to Sprague-Dawley rats at 500, 1,000, and 2,000 mg/kg body weight/day for 28 days. During the 28-day period, animals were examined for evidence of toxicity; there were no deaths, and in-life physical signs were normal. On day 29, the animals were exsanguinated, examined for gross pathology, and tissues were preserved for histopathology. Although statistical differences were noted in some hematology and clinical chemistry, they were of questionable biological significance. The results of the 28-day oral administration demonstrated a lack of toxicity of RH-Cu/Zn-SOD in rats. There were no treatment-related, toxicologically relevant changes in clinical signs, growth, food consumption, hematology, clinical chemistry, organ weights, or pathology. The no observed adverse effect level was greater than 2,000 mg/kg/day for RH-Cu/Zn-SOD in rats.


Assuntos
Superóxido Dismutase/toxicidade , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Contagem de Células Sanguíneas , Proteínas Sanguíneas/metabolismo , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Esquema de Medicação , Eletrólitos/sangue , Feminino , Hematócrito , Hemoglobinas/metabolismo , Histocitoquímica , Humanos , Masculino , Pichia/enzimologia , Pichia/genética , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/toxicidade , Superóxido Dismutase/administração & dosagem , Urinálise , gama-Glutamiltransferase/sangue
10.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 8): m1054-5, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22090841

RESUMO

The title compound, {[AgSm(C(6)H(4)NO(2))(2)(CH(3)CO(2))(H(2)O)]ClO(4)}(n), is a three-dimensional heterobimetallic complex constructed from a repeating dimeric unit. Only half of the dimeric moiety is found in the asymmetric unit; the unit cell is completed by crystallographic inversion symmetry. The Sm(III) ion is eight-coordinated by four O atoms of four different isonicotinate ligands, three O atoms of two different acetate ligands, and one O atom of a water mol-ecule. The two-coordinate Ag(I) ion is bonded to two N atoms of two different isonicotinate anions, thereby connecting the disamarium units. In addition, the isonicotinate ligands also act as bridging ligands, generating a three-dimensional network. The coordinated water mol-ecules link the carboxyl-ate group and acetate ligands by O-H⋯O hydrogen bonding. Another O-H⋯O hydrogen bond is observed in the crystal structure. The perchlorate ion is disordered over two sites with site-occupancy factors of 0.560 (11) and 0.440 (11), whereas the methyl group of the acetate ligand is disordered over two sites with site-occupancy factors of 0.53 (5) and 0.47 (5).

11.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 8): m1166-7, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22090920

RESUMO

In the title three-dimensional compound, [CoSm(6)(C(5)H(2)N(2)O(4))(4)(SO(4))(6)(H(2)O)(14)](n), the Co(II) ion is six-coordinated with two O atoms and two N atoms from two imidazole-4,5-dicarboxyl-ate ligands and two coordinated water mol-ecules, giving a slightly distorted octa-hedral geometry. One Sm(III) ion is eight-coordinated in a bicapped trigonal-prismatic coordination geometry by four O atoms from two imidazole-4,5-dicarboxyl-ate ligands, two O atoms from two SO(4) (2-) anions and two coordinated water mol-ecules. The other two Sm(III) ions are nine-coordinated in a tricapped trigonal-prismatic coordination geometry; one of these Sm(III) ions is bonded to four O atoms from two imidazole-4,5-dicarboxyl-ate ligands, three O atoms from three SO(4) (2-) anions and two water O atoms, and the other Sm(III) ion is coordinated by one O atom and one N atom from one imidazole-4,5-dicarboxyl-ate ligand, five O atoms from three SO(4) (2-) anions, as well as two coordinated water mol-ecules. The crystal structure is further stabilized by N-H⋯O, O-H⋯O, and C-H⋯O hydrogen-bonding inter-actions.

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