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1.
J Nanosci Nanotechnol ; 20(7): 4474-4479, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31968500

RESUMO

Carbon matrix metal organic frameworks (MOFs) hybrid is often used as electrode materials for lithium ion batteries (LIBs). Herein, we report three dimensional (3D) puffed rice inspired porous carbon (3DPRC) supported Co-MOFs derived composite by facile method. Co/C nanoparticles are uniformly dispersed on porous carbon sheets surface, forming unique 3D structures. As anode of LIBs, the prepared Co/C-3DPRC electrode shows excellent electrochemical properties when compared with the pristine Co/C electrode. With capacity of 430 mAh g-1 at 1C and 300 mAh g-1 at 10C is obtained in the composite electrode, respectively. The excellent properties can attribute to the Co/C-3DPRC interconnected porous framework with a high electrical conductivity and large surface area. Our developed design strategies can be extended for fabrication of other heteroatom doped carbon matrix hybrid for environmental energy fields.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31840859

RESUMO

The present study aimed to investigate the effects of protein restriction and subsequent realimentation on caecal barrier function, caecal microbial composition and metabolites in weaned piglets. Thirty-six 28-day-old weaned piglets were randomly assigned to a control group and a treatment group. The piglets were fed diets containing 18.83% (normal) or 13.05% (low) of crude protein from the 1st to 14th day, after which all piglets were fed diets containing 18.83% of crude protein from the 15th to 28th day. The results showed that protein restriction increased caecal bacterial diversity and richness as well as the abundance of Ruminococcus 2, Faecalibacterium and Lachnospiraceae_uncultured, but reduced the abundance and the gene copies of Lactobacillus in the treatment group compared with the control group on day 14. Protein restriction also decreased the concentrations of isovaleric acid and total branched-chain fatty acids. During the succedent protein realimentation stage, the abundance of Ruminococcaceae UCG-014 and the concentrations of lactic acid, acetic acid, butyric acid and total short-chain fatty acids were increased in the treatment group on day 28. Furthermore, the ammonia concentration was reduced, while the gene mRNA levels of caecal barrier function were increased in the treatment group both on days 14 and 28. In conclusion, dietary protein restriction and realimentation could change caecal microbial composition and metabolites, and eventually influence caecal barrier function. The present study may provide a new insight into protein restriction and realimentation in weaned piglets.

3.
Nutrients ; 11(8)2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31366090

RESUMO

Galacto-oligosaccharides (GOS), functional oligosaccharides with natural characteristics, are important active substances in milk that play an important role in the development of intestinal microbiota and the immune system of newborns. The intestinal maturation of piglets resembles that of human newborns and infants. Therefore, we used the newborn piglet model to study the effects of early-life GOS intervention. Six litters of neonatal piglets (10 piglets per litter) with the same average birth weight were divided into control (CON) and GOS (GOS) groups in each litter. Piglets in the GOS group were given 10 mL of GOS solution daily during the first week after birth, while piglets in the CON group were given the same dose of physiological saline orally. One pig per group from each litter was euthanized on day 8 and day 21. Results revealed that ileal microbiota composition was significantly enriched in Lactobacillus and unclassified Lactobacillaceae, and reduced in Clostridium sensu stricto on day 8 and day 21 after GOS intervention. Additionally, Escherichia significantly decreased on day 21 following the early-life GOS intervention. Moreover, the content of microbial metabolites, endocrine peptides, and the mRNA expression of anti-inflammatory cytokines and antimicrobial peptides increased in the GOS group. These findings provide guidelines for early prebiotic supplementation for lactating newborns.


Assuntos
Bactérias/classificação , Bactérias/metabolismo , Microbioma Gastrointestinal , Íleo/microbiologia , Oligossacarídeos/farmacologia , Suínos , Animais , Animais Recém-Nascidos , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Citocinas/genética , Citocinas/metabolismo , Ácidos Graxos Voláteis/química , Conteúdo Gastrointestinal/química , Conteúdo Gastrointestinal/microbiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Ácido Láctico , Oligossacarídeos/administração & dosagem , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
4.
Food Res Int ; 122: 183-190, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31229071

RESUMO

The stomach is a major digestive organ of the human body that plays a role in storing, mixing, reducing chylous particles and breaking down ingested foods. This study established a new artificial gastric digestive system (AGDS) with a human stomach shape and structure by a 3D digital technology. Two sets of symmetrical rollers and one set of contrary movement of the roller were used to simulate the peristalsis of the stomach, and a pH-stat workstation was applied to control the pH. The force, pepsin and gastric juice secretion, gastric emptying and pH changes of AGDS were tacked and validated. Besides, the digestion behavior of α-lactalbumin using AGDS model, static model and semi-dynamic model (pH and enzyme changes) were studied. The results showed that the hydrolysis and morphology of protein, peptide and amino acids accumulation obtained by AGDS were different from the static digestion and semi-dynamic digestion models, indicating pH and gastric motility had certain effect on protein hydrolysis, particularly in the pepsin activity changes at early stage of digestion. AGDS, verified by mechanical analysis and in vitro digestion experiments, indicated that it can provide α-LA protein solution with a true and reliable digestion profile in the stomach, and can be used as a potential dynamic gastric digestion model for the food development.

5.
Sensors (Basel) ; 19(3)2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30709028

RESUMO

The aim of this study was to use an electronic nose set up in our lab to detect and predict the freshness of pork, beef and mutton. Three kinds of freshness, including fresh, sub-fresh and putrid, was established by human sensory evaluation and was used as a reference for the electronic nose's discriminant factor analysis. The principal component analysis results showed the electronic nose could distinguish well pork, beef and mutton samples with different storage times. In the PCA figures, three kinds of meats samples all presented an approximate parabola trend during 7 days' storage time. The discriminant factor analysis showed electronic nose could distinguish and judge well the freshness of samples (accuracy was 89.5%, 84.2% and 94.7% for pork, beef and mutton, respectively). Therefore, the electronic nose is promising for meat fresh detection application.

6.
Food Chem ; 281: 78-84, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-30658768

RESUMO

This study's aim is to establish a new sensory sweetness definition and conversion method for five sugars. A "closed-type" question based on triangle test and paired comparison was used for sensory evaluation. The absolute threshold and nine sensory difference threshold values were determined and used to generate a sweet sensory difference strength curve. Defining absolute threshold of sucrose sweetness as 1, the sucrose sweetness at any concentration could be calculated via the curve. After taking the logarithm of each curve, sweetness index was calculated as 1, 1.12, 0.94, 1.29, and 1.25 for sucrose, glucose, fructose, lactose and maltose, respectively. Based on this, each sugar concentration and sweetness could be converted and calculated. Single sugar and mixed-sugars sweetness comparison experiments verified the new sweetness index and sweetness values were more accurate (83.3-100%) than those reported in previous studies. Therefore, this new definition and conversion method established more reliable references for sweet taste sensory applications.


Assuntos
Açúcares da Dieta/química , Limiar Sensorial , Paladar , Adulto , Limiar Diferencial , Feminino , Frutose/química , Glucose/química , Humanos , Lactose/química , Masculino , Maltose/química , Sacarose/química , Adulto Jovem
7.
J Agric Food Chem ; 67(3): 916-926, 2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30572705

RESUMO

Patients with inflammatory bowel disease (IBD) are usually advised to supplement various types of vitamin B12, because vitamin B12 is generally absorbed in the colon. Thus, in the current study, the influence of cyanocobalamin (CNCBL) or methylcobalamin (MECBL) ingestion on IBD symptoms will be investigated. Then, whether and how the application of various cobalamins would modify the taxonomic and functional composition of the gut microbiome in mice will be examined carefully. Dextran-sulfate-sodium-induced IBD mice were treated with MECBL or CNCBL; disease activity index (DAI) scores and intestinal inflammatory conditions of mice were evaluated. Fecal samples were collected; microbiota composition was determined with a 16s rRNA analysis; functional profiles were predicted by phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt); and short-chain fatty acids were measured. The consequence of higher relative abundances of Enterobacteriaceae and isomeric short-chain fatty acids by cobalamin treatment revealed that a high concentration of CNCBL but not MECBL supplementation obviously aggravated IBD. A microbial ecosystem rich in Escherichia/ Shigella and low in Lactobacillus, Blautia, and Clostridium XVIII was observed in IBD mice after a high concentration of CNCBL supplementation. In cobalamin-dependent enzymes, CNCBL was more efficient in the adenosylcobalamin system than MECBL and vice versa in the MECBL system. The distinct effects of various cobalamins were associated with the distribution and efficiency of vitamin-B12-dependent riboswitches. CNCBL had a strong inhibitory effect on all riboswitches, especially on btuB and pocR riboswitches from Enterobacteriaceae. CNCBL aggravated IBD via enhancing the proportion of Enterobacteriaceae organisms through riboswitch and enzyme systems. The present study provides a critical reference for offering a suitable amount and type of cobalamin during a symbiotic condition.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Doenças Inflamatórias Intestinais/microbiologia , Vitamina B 12/análogos & derivados , Vitamina B 12/administração & dosagem , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Suplementos Nutricionais/análise , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Filogenia
8.
J Agric Food Chem ; 67(2): 578-588, 2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30562014

RESUMO

Suckling piglets were used to investigate the response of colonic mucosa-associated microbiota composition, mucosal immune homeostasis, and barrier function to early life galactooligosaccharides (GOS) intervention. Ten milliliter 1 g/kg body weight GOS solutions and physiological saline solutions were fed to the newborn piglets in the GOS group and in the control (CON) group a week time, respectively. Six piglets from each group were euthanized on day 8 and day 21. GOS piglets had a higher abundance of short-chain fatty acids (SCFAs) producer such as Prevotella, Barnesiella, Parabacteroides, and Unclassified Porphyromonadaceae in colonic mucosa ( P < 0.05). In addition, the total SCFAs level in colonic digesta of GOS piglets increased on day 8 ( P < 0.05) and day 21 ( P = 0.064). Meanwhile, a higher SCFAs concentration in colon of the GOS piglets altered the gene expression of inflammatory cytokines (IL-8 and IL-10) and barrier proteins (ZO-1 and Claudin-1) through regulating the phosphorylation of the NFκB and AMPK signaling pathway. In summary, these results provide important insights and understandings to reveal the relationship between the mucosal microbiota colonization and intestinal function at the early life stage of piglets.


Assuntos
Colo/microbiologia , Microbioma Gastrointestinal , Mucosa Intestinal/imunologia , Oligossacarídeos/metabolismo , Suínos/imunologia , Suínos/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Colo/imunologia , Ácidos Graxos Voláteis/metabolismo , Feminino , Homeostase , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-8/genética , Interleucina-8/imunologia , Mucosa Intestinal/microbiologia , Masculino , Suínos/genética , Suínos/crescimento & desenvolvimento
9.
Artigo em Inglês | MEDLINE | ID: mdl-30349690

RESUMO

Background: Most research on galacto-oligosaccharides (GOS) has mainly focused on their prebiotic effects on the hindgut, but their beneficial effects on the small intestine (SI) have received little attention. Since jejunum is the important place to digest and absorb nutrients efficiently, optimal maturation of the jejunum is necessary for maintaining the high growth rate in the neonate. Therefore, this study investigates the effect of the early intervention with GOS on the intestinal development of the jejunum. Methods: A total of 6 litters of neonatal piglets (10 piglets per litter; Duroc × Landrace × Large White) with an average birth weight of 1.55 ± 0.05 kg received 1 of 2 treatments based on their assignment to either the control (CON) group or the GOS (GOS) group in each litter. Piglets in the GOS group were orally administrated 10 mL of a GOS solution (reaching 1 g GOS/kg body weight) per day from the age of 1 to 7 d; the piglets in the CON group were treated with the same dose of physiological saline. All piglets were weaned on d 21. On d 8 and 21 of the experimental trial, 1 pig per group from each of the 6 litters was euthanized. Results: The early intervention with GOS increased the average daily gains in the third week (P < 0.05). Decreased crypt depth was also observed in the jejunum of the piglets on d 21 (P < 0.05). The early intervention with GOS increased the jejunal lactase activity on d 8, maltase activity and sucrase activity on d 21 (P < 0.05). In addition, the early intervention with GOS also facilitated the mRNA expression of Sodium glucose co-transporter 1 (SGLT1) on d 8 and the mRNA expression of Glucose transporter type 2 (GLUT2) on d 21 (P < 0.05). It was further determined that GOS up-regulated the mRNA expression of preproglucagon (GCG), insulin-like growth factor 1 (IGF-1), insulin-like growth factor 1 receptor (IGF-1R) and epidermal growth factor (EGF). GOS also up-regulated the protein expression of glucagon-like peptide-2 (GLP-2) and EGF in the jejunum of the piglets. Furthermore, it was also found that GOS enhanced the protein expression of ZO-1 and occludin on d 8 (P < 0.05), as well as increased the mRNA expression of TGF-ß and decrease the mRNA expression of IL-12 (P < 0.05). Conclusions: These results indicate that GOS have a positive effect on piglet growth performance in addition to decreasing the crypt depth and enhancing functional development in jejunum of suckling piglets.

10.
Sensors (Basel) ; 18(9)2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30135351

RESUMO

A broad-spectrum sweet taste sensor based on Ni(OH)2/Ni electrode was fabricated by the cyclic voltammetry technique. This sensor can be directly used to detect natural sweet substances in 0.1 M NaOH solution by chronoamperometry method. The current value measured by the sensor shows a linear relationship with the concentration of glucose, sucrose, fructose, maltose, lactose, xylitol, sorbitol, and erythritol (R² = 0.998, 0.983, 0.999, 0.989, 0.985, 0.990, 0.991, and 0.985, respectively). Moreover, the characteristic value of this sensor is well correlated with the concentration and relative sweetness of eight sweet substances. The good correlation between the characteristic value of six fruit samples measured by the sensor and human sensory sweetness measured by sensory evaluation (correlation coefficient = 0.95) indicates that it can reflect the sweetness of fruits containing several sweet substances. In addition, the sensor also exhibits good long-term stability over 40 days (signal ratio fluctuation ranges from 91.5% to 116.2%). Thus, this broad-spectrum sensor is promising for sweet taste sensory application.

11.
Biol Pharm Bull ; 41(7): 1024-1033, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29962399

RESUMO

Acarbose and voglibose are the most widely used diabetes drugs as glycosidase inhibitors. In this study, the use of these two inhibitors significantly increased the content of starch in large intestine, and altered the concentration of short-chain fatty acids (SCFAs) by affecting the intestinal microbiota. However, there are some differences in the intestinal microbiome of the two groups of mice, mainly in bacteria such as Bacteroidaceae bacteroides and Desulfovibrionaceae desulfovibrio. The productions of acetate and propionate in caecum in voglibose group were significantly higher than those in acarbose group and two kinds of glycosidase inhibitors were close in the production of butyrate in caecum. The Tax4Fun analysis based on Kyoto Encyclopedia of Genes and Genomes (KEGG) data indicated that different productions of acetate and propionate between acarbose group and voglibose group may be related to 2-oxoisovalerate dehydrogenase and pyruvate oxidase. In addition, in-vitro experiments suggested that voglibose had less effect on epithelial cells than acarbose after direct stimulation. According to the recent researches of SCFAs produced by intestinal microbiota, our comparative study shown higher concentration of these beneficial fatty acids in the lumen of voglibose-treated mice, which implied a lower level of inflammation.


Assuntos
Ácidos Graxos Voláteis/análise , Microbioma Gastrointestinal/efeitos dos fármacos , Inibidores de Glicosídeo Hidrolases/farmacologia , Mucosa Intestinal/metabolismo , Acarbose/farmacologia , Animais , Bacteroidaceae/efeitos dos fármacos , Bacteroidaceae/metabolismo , Células CACO-2 , Desulfovibrionaceae/efeitos dos fármacos , Desulfovibrionaceae/metabolismo , Células Epiteliais/efeitos dos fármacos , Humanos , Inositol/análogos & derivados , Inositol/farmacologia , Intestinos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Amido/análise
12.
Meat Sci ; 128: 24-29, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28167402

RESUMO

A fast, sensitive and effective method based on the blood biochemical parameters for the detection of PSE meat was developed in this study. A total of 200 pigs were slaughtered in the same slaughterhouse. Meat quality was evaluated by measuring pH, electrical conductivity and color at 45min, 2h and 24h after slaughtering in M. longissimus thoracis et lumborum (LD). Blood biochemical parameters were determined in blood samples collected during carcass bleeding. Principal component analysis (PCA) biplot showed that high levels of exsanguination Creatine Kinase, Lactate Dehydrogenase, Aspertate aminotransferase, blood glucose and lactate were associated with the PSE meat, and the five biochemical parameters were found to be good indicators of PSE meat Discriminant function analysis (DFA) was able to clearly identify PSE meat using the five biochemical parameters as input data, and the class model is an effective diagnostic tool in pigs which can be used to detect the PSE meat and reduce economic loss for the company.


Assuntos
Qualidade dos Alimentos , Indústria de Embalagem de Carne/métodos , Carne/análise , Modelos Biológicos , Músculo Esquelético/crescimento & desenvolvimento , Sus scrofa/crescimento & desenvolvimento , Matadouros , Animais , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Glicemia/análise , China , Creatina Quinase/sangue , Cruzamentos Genéticos , Análise Discriminante , Condutividade Elétrica , Inspeção de Alimentos , Concentração de Íons de Hidrogênio , L-Lactato Desidrogenase/sangue , Ácido Láctico/sangue , Carne/classificação , Músculo Esquelético/química , Pigmentos Biológicos/análise , Análise de Componente Principal , Sus scrofa/sangue
13.
Anal Chim Acta ; 919: 11-19, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-27086094

RESUMO

This paper deals with a novel visualized attributive analysis approach for characterization and quantification of rice taste flavor attributes (softness, stickiness, sweetness and aroma) employing a multifrequency large-amplitude pulse voltammetric electronic tongue. Data preprocessing methods including Principal Component Analysis (PCA) and Fast Fourier Transform (FFT) were provided. An attribute characterization graph was represented for visualization of the interactive response in which each attribute responded by specific electrodes and frequencies. The model was trained using signal data from electronic tongue and attribute scores from artificial evaluation. The correlation coefficients for all attributes were over 0.9, resulting in good predictive ability of attributive analysis model preprocessed by FFT. This approach extracted more effective information about linear relationship between electronic tongue and taste flavor attribute. Results indicated that this approach can accurately quantify taste flavor attributes, and can be an efficient tool for data processing in a voltammetric electronic tongue system.


Assuntos
Nariz Eletrônico , Análise de Fourier , Oryza/química , Análise de Componente Principal , Paladar , Algoritmos , Preferências Alimentares
14.
Anal Chim Acta ; 690(2): 240-7, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21435482

RESUMO

A novel voltammetric electronic tongue, smart tongue, was employed to monitor the growth of mold and to differentiate between four types of mold grown in liquid medium. Principal component analysis (PCA) was used to extract the relevant information obtained by the smart tongue. Reference growth curves were based on measurements of dry weight and pH. The growth detected by the smart tongue was basically consistent with that observed by the measurement of dry weight and pH. The optimal combinations of electrodes and frequencies for monitoring growth were as follows: for Aspergillus, both the Pt and Au electrodes at 1 Hz, 10 Hz and 100 Hz; for Penicillium, the Pt and W electrodes at 100 Hz; for Mucor, the Pt, Pd and W electrodes at the three frequency segments; for Rhizopus, the Pd, Ti and Ag electrodes at the three frequency segments. The Ag electrode at 10 Hz or 100 Hz frequency could differentiate well between the four types of mold for culturing 6 h in the liquid media. Therefore, the smart tongue has a promising future as a modern rapid analytical technology for the real time detection of the growth of mold and for the classification model of mold.


Assuntos
Meios de Cultura/química , Técnicas Eletroquímicas/métodos , Eletrônica , Fungos/isolamento & purificação , Aspergillus/crescimento & desenvolvimento , Aspergillus/isolamento & purificação , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/instrumentação , Eletrodos , Fungos/crescimento & desenvolvimento , Ouro/química , Concentração de Íons de Hidrogênio , Chumbo/química , Mucor/crescimento & desenvolvimento , Mucor/isolamento & purificação , Penicillium/crescimento & desenvolvimento , Penicillium/isolamento & purificação , Platina/química , Análise de Componente Principal , Rhizopus/crescimento & desenvolvimento , Rhizopus/isolamento & purificação , Prata/química , Tungstênio/química
15.
Wei Sheng Wu Xue Bao ; 50(1): 113-8, 2010 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-20344949

RESUMO

OBJECTIVE: Electronic tongue is a modern analysis instrument and can detect very well the comprehensive information of liquid samples. Based on this, we employed the electronic tongue to detect the bacteria liquid culture, with the purpose of developing a new rapid method for the detection and identification of food-borne pathogens. METHODS: A novel voltammetric electronic tongue, smart tongue, was used to detect and differentiate 11 species of pathogenic Vibrio. Principal component analysis (PCA) was used to extract the relevant information obtained by the smart tongue. From the data evaluation, the score plots of PCA were obtained. RESULTS: According to the plots, we chose the most feasible working electrodes at the most favorable frequency segments were determined for our purpose. The results showed that the best electrode arrays and frequency segments to differentiate pathogenic Vibrio were titanium electrode in 100 Hz, silver electrode in 100 Hz and tungsten electrode in 1 Hz and 10 Hz, respectively. We differentiated 11 species of pathogenic Vibrio independently in the score plot of tungsten electrode in 1 Hz. We also distinguished all the Vibrio with the combination of two of other three electrodes and frequencies. CONCLUSION: Smartongue could differentiate well 11 species of pathogenic Vibrio from the results analysed by PCA. It has a promising future as a novel modern rapid analytical technology for detecting and distinguishing the pathogenic Vibrio. The method and results could be a good stencil-plate to the research of detecting the other food-borne pathogens with smartongue, and good reference information for the further study.


Assuntos
Técnicas Biossensoriais , Vibrio/isolamento & purificação , Eletrônica , Análise de Componente Principal
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