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1.
Carbohydr Polym ; 332: 121921, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431398

RESUMO

Curdlan is a unique (1,3)-ß-D-glucan with bioactivity and exceptional gelling properties. By chemical functionalization such as carboxymethylation, the physicochemical properties of curdlan can be significantly tailored. However, how the carboxymethylation extent of curdlan affects its rheology and gelation characteristics has yet to be fully understood. Herein, we investigated the impact of the degree of substitution (DS, ranging from 0.04 to 0.97) on the rheological and gelation behavior of carboxymethylated curdlan (CMCD). It was found that CMCD with DS below 0.20, resembling native curdlan, still retained its gelling capability. As the DS increased beyond 0.36, there was a significant increase in its water solubility instead of gelation, resulting in transparent solutions with steady/complex viscosities adhering to the Cox-Merz rule. Moreover, CMCD with high DS demonstrated the ability to undergo in-situ gelation in the presence of metal ions, attributed to the nonspecific electrostatic binding. Additionally, in vitro cytocompatibility testing showed positive compatibility across varying DS in CMCD. This research offers a holistic understanding of the viscosifying and gelling behaviors of CMCD with varying DS, thereby fostering their practical application as thickeners and gelling agents in fields ranging from food and biomedicine to cosmetics and beyond.


Assuntos
beta-Glucanas , beta-Glucanas/química , Glucanos/química , Géis/química , Água , Reologia
2.
Int J Biol Macromol ; 254(Pt 2): 127847, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37924910

RESUMO

The physicochemical properties and applications of polysaccharides are highly dependent on their chemical structures, including the monosaccharide composition, degree of substitution, and position of substituent groups in the backbone. The occurrence of side groups or side chains in the chain backbone of polysaccharides is often an essential factor influencing their conformational and physicochemical properties. Welan gum produced by the fermentation of Sphingomonas sp. ATCC 31555 microorganisms has been widely used in food, construction, and oil drilling fields. While understanding the physicochemical properties of welan gum solution has been highly developed, there is still little information about the determination strategy of the glycosyl side groups in welan gum. In this study, the NMR method was established to quantitatively determine the substituent groups in the chain backbone of welan gum. The delicate chemical structures of welan gum obtained at different fermentation conditions were clarified. The composition and content of side substituents were also identified by high-performance liquid chromatography to confirm the accuracy of NMR analysis. The quantitative determination of substituent groups in gellan gum based on NMR analysis was also elaborated for comparison. This work provides insights for profoundly understanding the structure-function relationship of welan gum.


Assuntos
Polissacarídeos Bacterianos , Sphingomonas , Polissacarídeos Bacterianos/química , Monossacarídeos , Fermentação
3.
Front Nutr ; 9: 1060630, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36532550

RESUMO

Objective: Dysphagia has become one of the important factors that cause malnutrition in the whole age group. At present, tube feeding is still the mainstream means to solve the problem of dysphagia. However, tube feeding has physical and mental harm to people, and the ways of non-tube feeding are relatively diversified. The significance of the thickening mechanism described in some articles to solve the problem of dysphagia is not clear. Setting and participants: All patients with dysphagia worldwide, including oropharyngeal dysphagia (OD) and non-oropharyngeal dysphagia. Methods: We searched the literature in Pubmed, Web of Science and Cochrane Library and initially browsed the titles and abstracts. We reviewed the full text of the articles that met our topic, and the language of the article was limited to English. Results: We found that food thickening to a certain degree (350-1,750 cP) can reduce the complications of choking, aspiration, reflux, and other complications in patients with dysphagia, and reduce the social disorder, anxiety, and other psychological problems caused by catheterization and surgery. Significantly, food science engineers should invite clinicians to intervene in the development of specialty foods from different perspectives such as clinical pathophysiology and fluid mechanics. Conclusion and implications: It is necessary to develop special foods for patients with dysphagia, which requires scientists from different disciplines to work together.

4.
Front Nutr ; 9: 853323, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35866082

RESUMO

Background: The optimal criteria for sarcopenia in the older Chinese population have not been defined. Consequently, this study aims to determine the optimal cutoffs of grip strength, appendicular skeletal muscle index (ASMI) using bioelectrical impedance analysis (BIA), and gait speed, comprising the best definition of sarcopenia for older Chinese populations. Methods: A total of 2,821 (1,398 men and 1,423 women) community-dwelling older people (≥60 years) and 409 (205 men and 204 women) young healthy adults (25-34 years) were recruited from three big cities in China. Besides gait speed and grip strength, we examined ASMI by BIA and dual-energy X-ray absorptiometry (DXA), comprising the three components of sarcopenia. DXA classification for low ASMI, 20th percentile among older adults in the study sample, was found to be best compared with the other existing classification, 1 SD and 2 SD below the mean for the young population, and was used as the gold standard to determine the optimal cutoffs of BIA using receiver operating characteristic curves (ROC). The cutoffs of handgrip strength and gait speed were determined following the same rule. Results: Using gender-specific 20th percentiles of DXA (6.53 kg/m2 for men and 5.40 kg/m2 for women), the cutoffs 7.05 kg/m2 for men and 5.85 kg/m2 for women were determined as optimal cutoffs of BIA by achieving the largest sensitivity (0.81, 95% CI: 0.63-0.93 for men and 0.90, 95% CI: 0.73-0.98 for women) and specificity greater than 0.80 (0.80, 95% CI: 0.72-0.87 for men and 0.81, 95% CI: 0.72-0.87 for women) in the ROC analysis. The 28.5 kg and 1.05 m/s for men and 18.6 kg and 1.01 m/s for women were determined as the cutoffs for handgrip strength and gait speed, respectively. Based on the derived cutoffs, 14.2% of men and 15.7% of women in the older Chinese study population were classified as sarcopenia. Conclusion: Notably, 7.05 kg/m2, 28.5 kg, and 1.05 m/s for men and 5.85 kg/m2, 18.6 kg, and 1.01 m/s for women were selected as the optimal cutoffs for low ASMI by BIA, handgrip strength, and gait speed, respectively. These optimal cutoffs will enhance practicability for screening sarcopenia in primary care and clinical settings.

5.
Compr Rev Food Sci Food Saf ; 19(2): 759-800, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-33325163

RESUMO

Structured lipids (SLs) refer to a new type of functional lipids obtained by chemically, enzymatically, or genetically modifying the composition and/or distribution of fatty acids in the glycerol backbone. Due to the unique physicochemical characteristics and health benefits of SLs (for example, calorie reduction, immune function improvement, and reduction in serum triacylglycerols), there is increasing interest in the research and application of novel SLs in the food industry. The chemical structures and molecular architectures of SLs define mainly their physicochemical properties and nutritional values, which are also affected by the processing conditions. In this regard, this holistic review provides coverage of the latest developments and applications of SLs in terms of synthesis strategies, physicochemical properties, health aspects, and potential food applications. Enzymatic synthesis of SLs particularly with immobilized lipases is presented with a short introduction to the genetic engineering approach. Some physical features such as solid fat content, crystallization and melting behavior, rheology and interfacial properties, as well as oxidative stability are discussed as influenced by chemical structures and processing conditions. Health-related considerations of SLs including their metabolic characteristics, biopolymer-based lipid digestion modulation, and oleogelation of liquid oils are also explored. Finally, potential food applications of SLs are shortly introduced. Major challenges and future trends in the industrial production of SLs, physicochemical properties, and digestion behavior of SLs in complex food systems, as well as further exploration of SL-based oleogels and their food application are also discussed.


Assuntos
Lipídeos/biossíntese , Lipídeos/síntese química , Digestão , Ácidos Graxos/química , Humanos , Metabolismo dos Lipídeos , Lipídeos/química , Estrutura Molecular , Valor Nutritivo , Compostos Orgânicos
6.
Carbohydr Polym ; 240: 116273, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32475561

RESUMO

Nanocomposites from plant-derived polysaccharides and proteins are green and sustainable materials that can be applied in various food and biomedical fields. In this work, we developed a novel core-shell nanocomposite from carboxymethylated corn fiber gum (CMCFG) and high nutritious pea protein (PP) for curcumin (Cur) delivery. In the preparation, PP-Cur complexes (PP-Cur) were formed at pH 7.0 and then coated by CMCFG via hydrophobic interactions to form PP-Cur-CMCFG complexes. Furthermore, the interactions between CMCFG and PP-Cur in the complexes were enhanced at pH 3.5 by electrostatic interactions. The resulting nanocomposite exhibited an excellent encapsulation performance for Cur with high Cur loading efficiency, good water dispersibility, and high chemical and thermal stability. Besides, the Cur-loaded core-shell nanocomposite also showed higher antioxidant and radical scavenging activities than Cur. Our results provide support for the use of plant-derived delivery systems as a strategy for the delivery of chemically unstable hydrophobic Cur.


Assuntos
Antioxidantes/química , Curcumina/química , Portadores de Fármacos/química , Nanocompostos/química , Proteínas de Ervilha/química , Gomas Vegetais/química , Zea mays , Liberação Controlada de Fármacos
7.
Food Sci Biotechnol ; 26(6): 1675-1683, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30263705

RESUMO

The objective of this study is to investigate the antiviral, anti-inflammatory, and antioxidant effects of the ethanol extract of Mentha piperita L. leaves (MPE). M. piperita L. leaves were extracted by reflux with ethanol. Total phenolic acid and total flavonoid content were determined. The antiviral activity of MPE against the respiratory syncytial virus (RSV) and the anti-inflammatory activity were evaluated in vitro. The levels of key pre-inflammatory mediators and cytokines including nitric oxide (NO), tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, and prostaglandin E2 (PGE2) were determined. The antioxidant activities were also evaluated using a colorimetry method. MPE contained high levels of phenolic acid and flavonoid, showed antiviral activity against RSV with a high selectivity index, and significantly decreased the production of NO, TNF-α, IL-6, and PGE2 in lipopolysaccharide-stimulated RAW 264.7 cells. Meanwhile, MPE showed potential free-radical scavenging activities. These results indicate that Mentha piperita L. might be a good source of medicinal plants.

8.
Wei Sheng Yan Jiu ; 41(3): 424-8, 2012 May.
Artigo em Chinês | MEDLINE | ID: mdl-23050441

RESUMO

OBJECTIVE: The study was carried out to determine serum retinol and carotenoid of infants and young children in rural areas, and to explore their related dietary factors. METHODS: A total of 254 rural healthy infants and young children aged 6-24 month-old were recruited from a program for health examination and feeding survey conducted in villages in Meibu of Linyi of Shandong Province by cluster sampling method. Serum retinol, beta-carotene, alpha-carotene, beta-cryptoxanthin and lutein + zeaxanthin were detected with HPLC. The frequency of food intake of babies during the past month was inquired from their mothers or baby-sitters. The relationship between serum retinol and carotenoid level with some factors related to feeding pattern was analyzed. RESULTS: The average serum retinol was (0.96 +/- 0.55) micromol/L with little variation by age (P > 0.05). The prevalence of serum vitamin A deficiency and marginal deficiency were 40.6% and 32.6%. The average serum beta-carotene, alpha-carotene, beta-cryptoxanthin and lutein + zeaxanthin were (0.056 +/- 0.088) micromol/L, (3.3 +/- 12.1) nmol/L, (27.0 +/- 45.2) nmol/L and (0.22 +/- 0.22) micromol/L, respectively, and no significant difference between age groups on serum beta-carotene, alpha-carotene and beta-cryptoxanthin (all were P > 0.05) except lutein + zeaxanthin (P < 0.05). Breast feeding and formula feeding were significant dietary factors influencing serum retinol and carotenoids levels. The frequency of breast-feeding was correlated significantly with serum beta-carotene (P < 0.05). Serum retinol was correlated positively with carotenoids and among carotenoids with each other (all were P < 0.001). CONCLUSION: Vitamin A deficiency and marginal deficiency were prevalent in the investigated infants and young children. Serum carotenoid was little variation with age, but was different significantly with dietary patterns fed by breast milk, formula, or fruits and vegetables.


Assuntos
Carotenoides/sangue , Dieta , Vitamina A/sangue , beta Caroteno/sangue , Aleitamento Materno , Criança , China , Criptoxantinas , Feminino , Frutas , Humanos , Lactente , Bem-Estar do Lactente , Leite Humano , População Rural , Verduras , Deficiência de Vitamina A
9.
Zhonghua Yu Fang Yi Xue Za Zhi ; 45(3): 259-62, 2011 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-21624240

RESUMO

OBJECTIVE: The objective of this study was to observe the interventional effect of cod liver oil supplementation on re-vaccination to hepatitis B virus (HBV) among infants and young children. METHODS: All 7-36 months old infants and young children, who had been vaccinated with obligatory HBV vaccines routinely by the national technical and administrative procedures for HBV vaccination on children of China, were convened among villages in Linyi, Shandong province, from October 2008 to March 2009. After detection of serum anti-HBV, one hundred children with lower serum anti-HBV were picked out for the randomized, double blinded, placebo controlled vitamin A supplementation study. The children in the intervention group (50 subjects) took 0.5 g condensed cod liver oil (containing 25 000 IU vitamin A and 2500 IU vitamin D(2)) every 15 days for six times. The children in the control group (50 subjects) were given corn oil with same volume. All children were re-vaccinated at the 30th and the 60th day of the experiment. The serum samples were collected from each child at the 90th day of the experiment. Retinol concentration in serum samples was analyzed with HPLC method before and after the intervention. The levels of serum anti-HBs were detected by the electro-chemi-luminescence immunoassay (ECLIA). RESULTS: Total 74 children finished the supplemental experiment and blood collection, 37 subjects in each group, respectively. After intervention, the serum retinol level in the experimental and control group were (404.1 ± 123.1) and (240.8 ± 92.8) µg/L (t = 6.441, P < 0.01), respectively. The serum anti-HBs levels in the experimental and control group were (2737.2 ± 2492.6) and (1199.7 ± 2141.6) U/L (t = 2.846, P < 0.01), respectively. The rate of weak or no-answer case in experimental and control groups was 0.00% (0/37) and 10.81% (4/37) (χ(2) = 4.229, P = 0.040), respectively. CONCLUSION: The results showed that vitamin A supplementation might enhance the re-vaccination reaction against HB vaccine in infants and young children.


Assuntos
Suplementos Nutricionais , Anticorpos Anti-Hepatite B/sangue , Vacinas contra Hepatite B/imunologia , Hepatite B/prevenção & controle , Vitamina A/uso terapêutico , Vitaminas/uso terapêutico , Pré-Escolar , Óleo de Fígado de Bacalhau/uso terapêutico , Método Duplo-Cego , Anticorpos Anti-Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Humanos , Imunidade Ativa , Lactente
10.
Wei Sheng Yan Jiu ; 32(2): 144-6, 2003 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-12793008

RESUMO

OBJECTIVE: Anemia morbidity in the population of adolescent and post-adolescent high school student has been paid little attention. Iron deficiency anemia is one of common maladies of micronutrient depletions, which has been proven to be damaging to cognition and intelligence performance. To probe into relationship between possible micronutrient deficiencies among post-adolescent schoolgirls and their poor intelligence performance comparing with same aged boys, this investigation was carried out. METHODS: Blood hemoglobin levels of 2624 senior high school student, including 1050 females and 1754 males with average age of 18.89 +/- 1.30 years, were determined at the time when they took part in physical examination for the National University Entrance Test. RESULTS: Anemic prevalence among female high-school graduates was 11.3%, much higher than 1.5% of males (P < 0.001). CONCLUSION: The high anemic morbidity in post-adolescent high schoolgirls exists, and it may be turned up to be one of causes of dropping behind in school test performance to them.


Assuntos
Anemia/epidemiologia , Hemoglobinas/análise , Adolescente , Anemia Ferropriva/epidemiologia , China/epidemiologia , Feminino , Humanos , Masculino , Prevalência , Fatores Sexuais
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