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1.
Food Chem ; 336: 127688, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32768904

RESUMO

The effects of carboxymethylation, hydroxypropylation and dual enzyme hydrolysis combined with heating on some physicochemical and functional properties, and antioxidant activity of coconut cake dietary fibre (CCDF) were studied. Results showed that both the hydroxypropylation and carboxymethylation could effectively improve (p < 0.05) the water retention capacity (WRC), oil retention capacity (ORC), viscosity, α-amylase inhibition activity (α-AAIR), glucose dialysis retardation index (GDRI), cation-exchange capacity, emulsifying capacity index (ECI) and bile adsorption capacity (BAC) of CCDF. Moreover, the cellulase and hemicellulase hydrolysis combination with heating significantly enhanced (p < 0.05) the soluble dietary fibre content, WRC, emulsion stability, GDRI, α-AAIR and BAC of CCDF; but caused decrease in ORC and browning of color. In addition, improvement of total phenol content, Fe2+ chelating ability, ABTS+· and O2-· scavenging activity were obtained in carboxymethylaticted CCDF. These effects were mainly attributed to the composition and structural modifications as evident from SEM, FT-IR and XRD analysis.


Assuntos
Antioxidantes/química , Celulase/metabolismo , Cocos/química , Fibras na Dieta/análise , Glicosídeo Hidrolases/metabolismo , Temperatura Alta , Adsorção , Fenômenos Químicos , Glucose/química , Hidrólise , Metilação , Solubilidade , Viscosidade
2.
Anim Sci J ; 91(1): e13466, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33043554

RESUMO

Sremski kulen is a wide diameter dry fermented sausage, produced from pork, seasoned with red spicy paprika, stuffed into pork cecum, and preserved by smoking, fermentation and drying. Due to specific ripening process, Sremski kulen is suitable for the accumulation of biogenic amines. Therefore, the aminogenesis was studied in traditionally produced Sremski kulen, taking into account the physicochemical parameters and microbial counts. The content of six biogenic amines (tryptamine, phenylethylamine, tyramine, histamine, putrescine, and cadaverine) was analyzed using high-performance liquid chromatography. The ripening process of Sremski kulen was slow followed by changes in aw and pH value as well as expressed proteolysis. The autochthonous microbiota showed pronounced decarboxylase activity. Tryptamine and phenylethylamine were detected at each examined ripening stage while histamine was not detected until the end of ripening (16.55 ± 2.33 mg/kg). Tyramine, cadaverine, and putrescine content significantly increased during the ripening period (p < .05). In the final product, cadaverine was the dominant biogenic amine (132.40 ± 5.05 mg/kg), followed by tyramine (115.80 ± 15.46 mg/kg) and putrescine (68.55 ± 2.39 mg/kg). Although the long ripening period greatly contributed to the accumulation of biogenic amines in final product, their content are not of concern from product safety aspects, but requires improvement in hygiene of production process.


Assuntos
Aminas Biogênicas/análise , Fermentação , Análise de Alimentos/métodos , Manipulação de Alimentos/métodos , Conservação de Alimentos/métodos , Qualidade dos Alimentos , Produtos da Carne/análise , Carne de Porco , Animais , Cadaverina/análise , Fenômenos Químicos , Cromatografia Líquida de Alta Pressão , Microbiologia de Alimentos , Inocuidade dos Alimentos , Concentração de Íons de Hidrogênio , Produtos da Carne/microbiologia , Proteólise , Putrescina/análise , Suínos , Tiramina/análise
3.
Anim Sci J ; 91(1): e13446, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32885584

RESUMO

The present study aimed to assess the palatability of sausages undergoing low-temperature fermentation and drying process. Lactobacillus sakei D-1001 or Lactobacillus salivarius A001 were used as starter cultures for fermentation, and the following properties of the sausages were investigated: colony-forming units of lactic acid bacteria; concentrations of lactic acid, protein, peptides, and free amino acids; distribution of protein; composition of free amino acids; and physical properties and taste. Alterations in the composition of proteins, peptides, and free amino acids as well as in various physical properties were caused by fermentation by lactic acid bacteria. A sensory test indicated that the palatability of the fermented sausages was greater than that of the non-fermented sausages, particularly in terms of hardness and juiciness. This was considered to be due to protein degeneration and changes in the physical properties of the sausages as a result of fermentation by lactic acid bacteria. However, the taste of the fermented sausages was sourer than that of the non-fermented sausages, and therefore, inferior. Our study revealed that the palatability of the sausages in terms of hardness and juiciness were increased by low-temperature fermentation by lactic acid bacteria and the drying process.


Assuntos
Temperatura Baixa , Dessecação/métodos , Fermentação , Análise de Alimentos , Manipulação de Alimentos/métodos , Qualidade dos Alimentos , Ácido Láctico/análise , Lactobacillus sakei , Lactobacillus salivarius , Produtos da Carne/análise , Paladar , Aminoácidos/análise , Animais , Fenômenos Químicos , Proteólise , Suínos
4.
J Oleo Sci ; 69(10): 1317-1329, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32908094

RESUMO

This study was aimed to prepare oleogels of whale spermaceti wax (WsWO) and lanolin wax (LnWO), and to compare them with well-known animal wax oleogels of shellac (ShWO) and beeswax (BsWO). WsWO, ShWO and BsWO were prepared at 5% (w/w) organogelator addition level, while LnWO was necessarily prepared at its minimum gelling concentration (C*) of 30% (w/w) addition level. All oleogels were posed high oil binding capacity and thermal reversibility. Melting peak temperatures were ordered as ShWO > BsWO > WsWO > LnWO by calorimetry. X-ray diffraction patterns indicated the presence of both ß´and ß type polymorphs, together with needle-like crystal morphology. Rheological analyses indicated that the stiffness of the gels were ordered as BsWO > WsWO > LnWO > ShWO. All showed good thixotropy, and thermal stability until 40°C (ShWO until 80°C). Finally, the sensory descriptive analysis indicated that LnWO had distinct negative sheep odor, but WsWO was quite similar to BsWO. Overall, LnWO determined to be not proper for food applications, but WsWO was shown to be a suitable oleogel for food applications.


Assuntos
Qualidade dos Alimentos , Alimentos , Odorantes/análise , Adulto , Animais , Fenômenos Químicos , Cristalização , Feminino , Humanos , Lanolina , Masculino , Pessoa de Meia-Idade , Compostos Orgânicos/química , Resinas Vegetais , Reologia , Temperatura , Ceras , Baleias , Adulto Jovem
5.
J Oleo Sci ; 69(10): 1219-1230, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32908101

RESUMO

Quality parameters of potato chips (flat and serrated) fried either in palm oil (PO) alone or containing natural (thyme (TPO) and rosemary (RPO) extracts) and synthetic BHT (BPO) antioxidants were evaluated during storage period. The free fatty acid and peroxide values of chips fried in PO (control) were found between 0.18 and 0.21% to 1.00 and 1.04 meqO2/kg during the first storage month, respectively. However, these values were 0.07-0.10% and 0.55-0.90 meqO2/kg for chips fried in TPO, respectively. The water contents increased when storage time increased from 1 to 7 month and their values changed between 0.49 and 1.95% (flat potato chips in BPO) and between 0.88 and 1.24% (serrated potato chips in TPO). The total trans-fat contents were 0.13% (serrated potato chips in BPO) and 0.35% (both flat and serrated potato chips in PO) at the start of storage. The total trans-fat content after 7 months were 0.13% (PO fried flat and serrated potato chips) and 0.17% (serrated potato chips fried in BPO, TPO and RPO). The acrylamide contents varied between 152 (serrated potato chips in PO) and 540 µg/kg (flat potato chips fried in RPO) at the beginning of storage. However, the acrylamide contents changed during 7th storage month and ranged from 182 (serrated potato chips in PO) to 518 µg/kg (flat potato chips in RPO). Among fatty acids, while palmitic acid are determined between 37.14 (flat chips in PO) and 41.60% (serrated chips in TPO), oleic acid varied between 30.0 (flat chips in RPO) and 33.00% (serrated chips in PO). Sensory evaluation showed that PO containing antioxidants showed better consumer preference for potato chips until the end of storage.


Assuntos
Antioxidantes/análise , Hidroxitolueno Butilado/análise , Culinária/métodos , Análise de Alimentos , Manipulação de Alimentos/métodos , Qualidade dos Alimentos , Armazenamento de Alimentos , Óleo de Palmeira , Extratos Vegetais , Rosmarinus/química , Solanum tuberosum/química , Paladar , Thymus (Planta)/química , Acrilamida/análise , Fenômenos Químicos , Ácidos Graxos não Esterificados/análise , Humanos , Peróxidos/análise , Ácidos Graxos Trans/análise
6.
PLoS One ; 15(9): e0238385, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32936810

RESUMO

A lack of replicable test systems that realistically simulate hot water premise plumbing conditions at the laboratory-scale is an obstacle to identifying key factors that support growth of opportunistic pathogens (OPs) and opportunities to stem disease transmission. Here we developed the convectively-mixed pipe reactor (CMPR) as a simple reproducible system, consisting of off-the-shelf plumbing materials, that self-mixes through natural convective currents and enables testing of multiple, replicated, and realistic premise plumbing conditions in parallel. A 10-week validation study was conducted, comparing three pipe materials (PVC, PVC-copper, and PVC-iron; n = 18 each) to stagnant control pipes without convective mixing (n = 3 each). Replicate CMPRs were found to yield consistent water chemistry as a function of pipe material, with differences becoming less discernable by week 9. Temperature, an overarching factor known to control OP growth, was consistently maintained across all 54 CMPRs, with a coefficient of variation <2%. Dissolved oxygen (DO) remained lower in PVC-iron (1.96 ± 0.29 mg/L) than in PVC (5.71 ± 0.22 mg/L) or PVC-copper (5.90 ± 0.38 mg/L) CMPRs as expected due to corrosion. Further, DO in PVC-iron CMPRs was 33% of that observed in corresponding stagnant pipes (6.03 ± 0.33 mg/L), demonstrating the important role of internal convective mixing in stimulating corrosion and microbiological respiration. 16S rRNA gene amplicon sequencing indicated that both bulk water (Padonis = 0.001, R2 = 0.222, Pbetadis = 0.785) and biofilm (Padonis = 0.001, R2 = 0.119, Pbetadis = 0.827) microbial communities differed between CMPR versus stagnant pipes, consistent with creation of a distinct ecological niche. Overall, CMPRs can provide a more realistic simulation of certain aspects of premise plumbing than reactors commonly applied in prior research, at a fraction of the cost, space, and water demand of large pilot-scale rigs.


Assuntos
Água Potável/efeitos adversos , Água Potável/microbiologia , Engenharia Sanitária/instrumentação , Microbiologia da Água , Biofilmes/crescimento & desenvolvimento , Fenômenos Químicos , Cobre/química , Desenho de Equipamento , Humanos , Ferro/química , Microbiota/genética , Modelos Biológicos , Infecções Oportunistas/etiologia , Infecções Oportunistas/microbiologia , Cloreto de Polivinila/química , RNA Ribossômico 16S/genética , Temperatura , Abastecimento de Água
7.
Proc Natl Acad Sci U S A ; 117(37): 22674-22683, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32868438

RESUMO

Compartmentalization of biochemical processes underlies all biological systems, from the organelle to the tissue scale. Theoretical models to study the interplay between noisy reaction dynamics and compartmentalization are sparse, and typically very challenging to analyze computationally. Recent studies have made progress toward addressing this problem in the context of specific biological systems, but a general and sufficiently effective approach remains lacking. In this work, we propose a mathematical framework based on counting processes that allows us to study dynamic compartment populations with arbitrary interactions and internal biochemistry. We derive an efficient description of the dynamics in terms of differential equations which capture the statistics of the population. We demonstrate the relevance of our approach by analyzing models inspired by different biological processes, including subcellular compartmentalization and tissue homeostasis.


Assuntos
Células/química , Modelos Biológicos , Bioquímica , Células/metabolismo , Fenômenos Químicos , Redes Reguladoras de Genes , Cinética , Modelos Teóricos , Proteínas/genética , Proteínas/metabolismo , Processos Estocásticos
8.
Anim Sci J ; 91(1): e13458, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32996238

RESUMO

This study investigates the effect of the addition of plant-derived extracts (control, garlic extract or a combination of carvacrol, thymol, cinnamic aldehyde and eugenol oils extracts) to pig feedstuff and the reduction in salt content (NaCl or a mixture 60:40 sodium chloride:potassium lactate) on some physicochemical characteristics and consumer acceptability of dry-fermented sausages. Six different batches were formulated. The pH, color, lipid oxidation, and microbial counts were measured, and a consumer home test was performed. Both the use of a plant-derived extract and salt type affected the dry-fermented sausage characteristics. The low-salt batches presented a lower pH and higher microbial counts than the control. The salt reduction affected the color but only in the oil batches, resulting in higher L* and lower a* values. The oil batches presented the highest TBAR values (>1 mg/kg), suggesting that antioxidant compounds present into the meat were not bioavailable on the sausages or were missed during the curing process. The use of plant-derived extracts affected to consumer acceptability, whereas salt replacement did not. Oil batches scored lower than the other. From the current results, the oil extract would not be a recommended additive in pig feedstuff, especially when a low-salt strategy will be employed.


Assuntos
Ração Animal , Dieta/veterinária , Qualidade dos Alimentos , Produtos da Carne , Extratos Vegetais/administração & dosagem , Cloreto de Sódio/análise , Suínos , Paladar , Animais , Fenômenos Químicos , Cor , Fermentação , Humanos , Concentração de Íons de Hidrogênio , Peroxidação de Lipídeos , Produtos da Carne/análise
9.
Life Sci ; 260: 118182, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32781063

RESUMO

BACKGROUND: Chronic diseases are a major cause of mortality worldwide, and despite the recent development in treatment modalities, synthetic drugs have continued to show toxic side effects and development of chemoresistance, thereby limiting their application. The use of phytochemicals has gained attention as they show minimal side effects. Diosgenin is one such phytochemical which has gained importance for its efficacy against the life-threatening diseases, such as cardiovascular diseases, cancer, nervous system disorders, asthma, arthritis, diabetes, and many more. AIM: To evaluate the literature available on the potential of diosgenin and its analogs in modulating different molecular targets leading to the prevention and treatment of chronic diseases. METHOD: A detailed literature search has been carried out on PubMed for gathering information related to the sources, biosynthesis, physicochemical properties, biological activities, pharmacokinetics, bioavailability and toxicity of diosgenin and its analogs. KEY FINDINGS: The literature search resulted in many in vitro, in vivo and clinical trials that reported the efficacy of diosgenin and its analogs in modulating important molecular targets and signaling pathways such as PI3K/AKT/mTOR, JAK/STAT, NF-κB, MAPK, etc., which play a crucial role in the development of most of the diseases. Reports have also revealed the safety of the compound and the adaptation of nanotechnological approaches for enhancing its bioavailability and pharmacokinetic properties. SIGNIFICANCE: Thus, the review summarizes the efficacy of diosgenin and its analogs for developing as a potent drug against several chronic diseases.


Assuntos
Doença Crônica/tratamento farmacológico , Diosgenina/uso terapêutico , Animais , Disponibilidade Biológica , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/prevenção & controle , Fenômenos Químicos , Doença Crônica/prevenção & controle , Diosgenina/análogos & derivados , Diosgenina/farmacocinética , Humanos , Inflamação/tratamento farmacológico , Neoplasias/tratamento farmacológico , Doenças do Sistema Nervoso/tratamento farmacológico , Fitoterapia , PubMed , Sementes/química , Transdução de Sinais/efeitos dos fármacos , Trigonella
10.
Nat Commun ; 11(1): 3880, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32759942

RESUMO

Geological sources of H2 and abiotic CH4 have had a critical role in the evolution of our planet and the development of life and sustainability of the deep subsurface biosphere. Yet the origins of these sources are largely unconstrained. Hydration of mantle rocks, or serpentinization, is widely recognized to produce H2 and favour the abiotic genesis of CH4 in shallow settings. However, deeper sources of H2 and abiotic CH4 are missing from current models, which mainly invoke more oxidized fluids at convergent margins. Here we combine data from exhumed subduction zone high-pressure rocks and thermodynamic modelling to show that deep serpentinization (40-80 km) generates significant amounts of H2 and abiotic CH4, as well as H2S and NH3. Our results suggest that subduction, worldwide, hosts large sources of deep H2 and abiotic CH4, potentially providing energy to the overlying subsurface biosphere in the forearc regions of convergent margins.


Assuntos
Ecossistema , Hidrogênio/química , Metano/química , Minerais/química , Compostos Orgânicos/química , Termodinâmica , Amônia/química , Fenômenos Químicos , Fenômenos Geológicos , Sulfeto de Hidrogênio/química , Fenômenos Mecânicos , Fenômenos de Química Orgânica , Alcaloides de Triptamina e Secologanina/química , Erupções Vulcânicas
11.
J Oleo Sci ; 69(9): 1043-1049, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32788510

RESUMO

The 2-ethylhexyl stearate is used as a bio-lubricant in various cosmetic products. The present study is focused on the biocatalyzed esterification of 2-ethylhexanol and stearic acid to form 2-ethylhexyl stearate catalyzed by Fermase CALB 10000 in the presence of ultrasound treatment. The maximum conversion (95.87%) was obtained at molar ratio of 2-ethylhexanol to stearic acid 2:1, enzyme amount of 2 % (w/w), power 80 W, duty cycle 50 % and temperature 50°C in comparatively short reaction time (3 h) in the presence of Fermase as a catalyst. At optimum conditions, it is observed that in the presence of ultrasound; the reaction time minimizes up to 4 h as compared to mechanical stirring method (7 h). The physiochemical properties for the 2-ethylhexyl palmitate were also evaluated.


Assuntos
Hexanóis/química , Estearatos/síntese química , Ondas Ultrassônicas , Biocatálise , Fenômenos Químicos , Enzimas Imobilizadas/química , Esterificação , Estearatos/química , Ácidos Esteáricos/química , Temperatura , Fatores de Tempo
12.
J Oleo Sci ; 69(9): 1021-1030, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32788513

RESUMO

A novel jellyfish-shaped triazine hexamer quaternary ammonium chloride surfactant (TH12QC) was synthesized, which consisted of one triazine spacer group and six long flexible hydrophobic chains. The molecular structure and aggregation behavior of TH12QC was investigated by nuclear magnetic resonance (NMR), surface tension, electrical conductivity, dynamic light scattering (DLS), transmission electron microscope (TEM), etc. The results show that the jellyfish-shaped TH12QC has better surface activity and lower surface tension than traditional ionic and Gemini surfactants in aqueous solution. There are two inflection points in the curve of conductivity versus concentration of the TH12QC aqueous solution, which correspond to the critical aggregation concentration (CAC) and the critical micelle concentration (CMC) respectively. The existence of CAC indicates that there is a pre-aggregation process before TH12QC forms micelles. The results of DLS and TEM show that network pre-aggregation, spherical aggregation and dense spherical aggregation were observed in different concentration of TH12QC aqueous solution, and the electrostatic equilibrium of the system subtly depends on the concentration of the solution. In addition, intramolecular and intermolecular hydrogen bonding is also an important factor. This study provides a method for studying the aggregation behavior and morphology of oligomeric surfactants with rigid spacer groups.


Assuntos
Cloreto de Amônio/química , Cloreto de Amônio/síntese química , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/síntese química , Tensoativos/química , Tensoativos/síntese química , Triazinas/química , Triazinas/síntese química , Fenômenos Químicos , Difusão Dinâmica da Luz , Condutividade Elétrica , Ligação de Hidrogênio , Micelas , Estrutura Molecular , Soluções , Tensão Superficial , Água/química
13.
Yakugaku Zasshi ; 140(8): 1071-1080, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32741865

RESUMO

The purpose of the present study was to establish a novel method to evaluate water penetration rates by combining the local dynamic contact angle and thermographic approach to characterize water conduction properties in orally disintegrating (OD) tablets. The OD tablet tester OD-mate was used to measure the disintegration times of OD tablets. Other formulation characteristics, such as tablet hardness and friability, were evaluated. By examining three formulation characteristics, such as the disintegration time, tablet hardness, and friability, of 33 OD tablets for generic drugs, four characteristic OD tablets containing aripiprazole were selected. To quantitatively evaluate water penetration rates into the tablet interior, we measured the dynamic contact angle after dropping water locally on the tablet surface. Linearity with a high correlation coefficient was observed for each of the initial time-dependent changes in the dynamic contact angle. Water penetration rates into tablets were approximately twice as fast for Pharmaceuticals A and B than for Pharmaceuticals C and D. These rates were consistent with changes observed in tablet thermographic imaging. The relationship between the rapid disintegration of the tablet and its physical strength was discussed based on the internal structure of the tablet by X-ray CT and the additives of each OD tablet. The present results demonstrated that the water penetration rates of OD tablets, as measured by dynamic contact angle, may accurately detect differences in disintegration times in the human oral cavity.


Assuntos
Química Farmacêutica/métodos , Comprimidos , Termografia , Administração Oral , Fenômenos Químicos , Dureza , Solubilidade , Água
14.
Yakugaku Zasshi ; 140(8): 955-960, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32741867

RESUMO

A nickel-aluminium-zirconium complex-layered hydroxide (NAZ), which was synthesized using each inorganic sulfate mixing ratio of 0.9 : 1.0 : 0.1, was prepared and calcined at different temperatures. The physicochemical properties of the NAZ were analyzed by scanning electron microscopy, specific surface area, number of hydroxyl groups, and pore volume. The specific surface area, number of hydroxyl groups, and pore volume of NAZ was 51.9 m2/g, 1.08 mmol/g, and 0.27 µL/g, respectively. The amount of phosphate ion adsorbed onto NAZ was higher than that onto calcined NAZ at different temperatures. Therefore, the interaction between phosphate ions and NAZ was assessed using the elemental distribution analysis and the binding energy. After adsorption, the intensity of phosphorus atoms increased, indicating that the phosphate ions were adsorbed onto the NAZ surface. Additionally, phosphorus peaks (189 eV for 2s and 130 eV for 2p), which were not detected before adsorption, were clearly detected after adsorption. On the other hand, the intensity of the sulfur peak (165 eV for 2p) decreased after adsorption. Thus, we evaluated the ion exchange between phosphate ion and sulfate ion in the interlayer space of the NAZ. As a result, the correlation coefficient between the amount of phosphate ion adsorbed and the amount of sulfate ion released was positively correlated (r=0.960). Therefore, it can be clearly stated that one of the adsorption mechanisms of phosphate ions was related to ion exchange in the interlayer space of the NAZ. These findings are useful for preventing the eutrophication and recovery of phosphate ion in water environments.


Assuntos
Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Hidróxidos/química , Hidróxidos/síntese química , Fosfatos/química , Adsorção , Alumínio , Fenômenos Químicos , Eutrofização , Troca Iônica , Íons , Microscopia Eletroquímica de Varredura , Níquel , Zircônio
15.
J Oleo Sci ; 69(8): 865-870, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32641610

RESUMO

We studied the physicochemical properties of 1:1 stoichiometric complexes of acylglutamic acids (CnGlu) with tertiary alkylamines (CnDMA) in water at their low and high concentrations. Static surface tensiometry suggested that the critical micelle concentration (cmc) decreased with increasing hydrophobic chain length of the complexes. In addition, CnGlu-CnDMA yielded lower cmc than the C12Glu single system. In the region of high concentrations, several phase states including isotropic liquid (L1) phase, hexagonal liquid crystal (H1) phase, bicontinuous cubic liquid crystal (V1) phase, and lamellar liquid crystal (Lα) phase were observed. Assemblies with lesser positive curvature tend to be formed with increasing complex concentration, increasing temperature, and increasing hydrophobic chain length. Additionally, the complex formation resulted in the molecular assemblies with lesser positive curvature.


Assuntos
Aminas/química , Fenômenos Químicos , Ácido Glutâmico/química , Tensoativos/química , Água/química , Interações Hidrofóbicas e Hidrofílicas , Cristais Líquidos , Micelas , Tensão Superficial , Temperatura
16.
J Oleo Sci ; 69(7): 743-750, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32612024

RESUMO

In this study, two new mixed-ligand coordination polymers {[Co(bbi)(tdc)]·5H2O}n (1, bbi = 1,4-bis(imidazolyl)butane) and {[Cu2(bimb)(H2O)(µ3-tdc)2(DMF)2]·H2O}n (2, bimb = 4-bis(1H-imidazol-1-yl-methyl)benzene) were synthesized under the solvothermal conditions via reaction of 2,5-thiophenedicarboxylic acid (H2tdc) with the corresponding metal salts in the existence of different flexible bis-imidazole ligands (bbi for 1 and bimb for 2). The as-prepared two structures were detected via the single crystal X-ray diffraction (SXRD) and then characterized via the analysis of element, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) as well as infrared (IR) spectroscopy. Furthermore, the protective activity of the compound on the mice with ischemic stroke was evaluated. Firstly, the real time reverse transcription-polymerase chain raction (RT-PCR) was carried out to determine the effect of compounds 1 and 2 against the relative expression level of the glucagon-like peptide 1 receptors (glp1r) on the cerebrovascular endothelial cells. Next, the Morris Water Maze Experiment was also used to detect the improvement function of compounds 1 and 2 on the nice mice cognitive function.


Assuntos
Encéfalo/metabolismo , Complexos de Coordenação/síntese química , Complexos de Coordenação/farmacologia , Expressão Gênica/efeitos dos fármacos , Receptor do Peptídeo Semelhante ao Glucagon 1/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Metais/química , Polímeros/síntese química , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/genética , Tiofenos/química , Animais , Encéfalo/citologia , Fenômenos Químicos , Cognição/efeitos dos fármacos , Complexos de Coordenação/uso terapêutico , Cristalização , Células Endoteliais/metabolismo , Imidazóis/química , Ligantes , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Modelos Moleculares , Conformação Molecular , Polímeros/química , Relação Estrutura-Atividade , Difração de Raios X
17.
SAR QSAR Environ Res ; 31(8): 597-613, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32646236

RESUMO

Here we report a new predictive model for autoignition temperature (AIT), an important physical parameter widely used to assess potential safety hazards of combustible materials. Available structure-AIT data extracted from different sources were critically analysed. Support vector regression (SVR) models on different data subsets were built in order to identify a reliable compound set on which a realistic model could be built. This led to a selection of the dataset containing 875 compounds annotated with AIT values. The thereupon-based SVR model performs reasonably well in cross-validation with the determination coefficient r 2 = 0.77 and mean absolute error MAE = 37.8°C. External validation on 20 industrial compounds missing in the training set confirmed its good predictive power (MAE = 28.7°C).


Assuntos
Fogo , Relação Quantitativa Estrutura-Atividade , Temperatura , Fenômenos Químicos , Análise de Dados , Modelos Químicos
18.
Yakugaku Zasshi ; 140(7): 913-921, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32612056

RESUMO

Controlling the physicochemical properties of a drug formulation is important for proper drug efficacy, since in the gastrointestinal tract many drugs undergo dissolution, limiting their efficacy. Factors affecting a drug's physicochemical properties include its crystal habit. Therefore, we predicted the crystal habit by molecular simulation for the purpose of controlling crystal morphology. In this study, we used aspirin as a model compound. By performing simulations based on known crystal structure data, we trained the simulation algorithm to produce the cubic and plate-like morphologies of crystals actually obtained. By these methods, we showed that the crystal plane of the crystal form actually obtained coincides with the characteristic crystal plane obtained by simulation. Furthermore, to consider the influence of the crystallization solvent on crystal growth, we simulated adsorption of solvent molecules on characteristic crystal planes. The difference in adsorption energy of the solvent molecules prevents the aspirin molecules from attaching to the crystal plane. As a result, we concluded that the crystal habit was caused by the difference in growth rate of the crystal plane. By applying the methods developed in this research, the growth of crystal planes can be predicted by molecular simulation, making it possible to efficiently obtain crystal forms with optimal physical properties for drug development. We believe that further development of this approach will lead to dramatic decreases in the cost and duration of drug development.


Assuntos
Aspirina/química , Adsorção , Fenômenos Químicos , Cristalização , Composição de Medicamentos , Previsões , Modelos Moleculares , Solventes/química
19.
Food Chem ; 332: 127372, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32615381

RESUMO

The physicochemical and physiological properties of soluble dietary fiber (SDF) and insoluble dietary fiber (IDF) from bamboo shoots were investigated in present study. IDF showed better adsorption capacity than the corresponding SDF from the same species. Microstructure observation results indicated that the surface of IDF was porous, whereas the SDF was relatively flat and compact. The cholesterol-adsorption capacities of IDF and SDF from Fargesia spathacea were relatively higher than the other species. Both SDF and IDF from F. spathacea showed potential prebiotic effects, although the Lactobacillus and Bifidobacterium promotion effects of SDF were relatively stronger than IDF. Compared with control, the concentration of total short chain fatty acids in IDF and SDF supplement groups were increased by 1.28 and 0.71 folds, respectively. These results suggested that F. spathacea dietary fibers with strong cholesterol-adsorption activity and prebiotic potential, could be used as a bioactive ingredient in functional foods production.


Assuntos
Anticolesterolemiantes/química , Anticolesterolemiantes/farmacologia , Fibras na Dieta/farmacologia , Caules de Planta/química , Poaceae/química , Prebióticos , Fenômenos Químicos , Suplementos Nutricionais , Alimento Funcional/análise
20.
Food Chem ; 333: 127489, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32653685

RESUMO

To improve the utilization of cod skin collagen peptides (CSCP), we heated them with xylose at 80 °C, 100 °C, and 120 °C for up to 150 min to prepare xylose-CSCP Maillard reaction products (MRPs), and then investigated their physicochemical and functional properties. The results showed that Arg, Lys, Phe, and Asp were the major amino acids involved in the Maillard reaction. After being heated at 120 °C for 150 min, the ABTS scavenging activity and reducing power of xylose-CSCP MRPs were 99.59% and 0.887 absorbance units, respectively. Xylose-CSCP MRPs had better emulsifying properties and foaming properties than CSCP. Furthermore, 26 volatile compounds, including 2,5-dimethyl-pyrazine and 2-ethyl-3,5-dimethylpyrazine, were identified from xylose-CSCP MRPs by gas chromatography-ion mobility spectrometry. Newly formed heterocyclic compounds might be responsible for the flavor and antioxidant capacity of xylose-CSCP MRPs. These results suggest the potential for xylose-CSCP MRPs to serve as functional food ingredients.


Assuntos
Fenômenos Químicos , Colágeno/química , Gadus morhua , Reação de Maillard , Peptídeos/química , Pele/química , Xilose/química , Animais , Antioxidantes/química , Temperatura Alta , Paladar
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