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1.
Int J Biol Macromol ; : 134409, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39097042

RESUMO

Alginate is a linear polysaccharide with a modifiable structure and abundant functional groups, offers immense potential for tailoring diverse alginate-based materials to meet the demands of biomedical applications. Given the advancements in modification techniques, it is significant to analyze and summarize the modification of alginate by physical, chemical and biological methods. These approaches provide plentiful information on the preparation, characterization and application of alginate-based materials. Physical modification generally involves blending and physical crosslinking, while chemical modification relies on chemical reactions, mainly including acylation, sulfation, phosphorylation, carbodiimide coupling, nucleophilic substitution, graft copolymerization, terminal modification, and degradation. Chemical modified alginate contains chemically crosslinked alginate, grafted alginate and oligo-alginate. Biological modification associated with various enzymes to realize the hydrolysis or grafting. These diverse modifications hold great promise in fully harnessing the potential of alginate for its burgeoning biomedical applications in the future. In summary, this review provides a comprehensive discussion and summary of different modification methods applied to improve the properties of alginate while expanding its biomedical potentials.

2.
Food Chem ; 451: 139530, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38703723

RESUMO

With increasing consumer health awareness and demand from some vegans, plant proteins have received a lot of attention. Plant proteins have many advantages over animal proteins. However, the application of plant proteins is limited by a number of factors and there is a need to improve their functional properties to enable a wider range of applications. This paper describes the advantages and disadvantages of traditional methods of modifying plant proteins and the appropriate timing for their use, and collates and describes a method with fewer applications in the food industry: the Hofmeister effect. It is extremely simple but efficient in some respects compared to traditional methods. The paper provides theoretical guidance for the further development of plant protein-based food products and a reference value basis for improving the functional properties of proteins to enhance their applications in the food industry, pharmaceuticals and other fields.


Assuntos
Proteínas de Plantas , Proteínas de Plantas/química , Manipulação de Alimentos
3.
ChemSusChem ; 16(15): e202300174, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37338272

RESUMO

Traditionally, phenols used to prepare phenol-formaldehyde (PF) resin adhesives are obtained from phenolic compounds and various chemicals, which are extracted from petroleum-based raw materials. Lignin, a sustainable phenolic macromolecule in the cell wall of biomass with an aromatic ring and a phenolic hydroxyl group similar to those of phenol, can be an ideal substitute for phenol in PF resin adhesives. However, only a few lignin-based adhesives are produced on a large scale in industry, mainly because of the low activity of lignin. Preparing lignin-based PF resin adhesives with exceptional achievements by modifying lignin instead of phenol is an efficient method to improve the economic benefits and protect the environment. In this review, the latest progress in the preparation of PF resin adhesives via lignin modification, including chemical, physical, and biological modifications, is discussed. In addition, the advantages and disadvantages of different lignin modification methods for adhesives are compared and discussed, and future research directions for the synthesis of lignin-based PF resin adhesives are proposed.

4.
Food Res Int ; 169: 112913, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37254349

RESUMO

Wheat is widely available in people's daily diets. However, some people are currently experiencing IgE-mediated allergic reactions to wheat-based foods, which seriously impact their quality of life. Thus, it is imperative to provide comprehensive knowledge and effective methods to reduce the risk of wheat allergy (WA) in food. In the present review, recent advances in WA symptoms, the major allergens, detection methods, opportunities and challenges in establishing animal models of WA are summarized and discussed. Furthermore, an updated overview of the different modification methods that are currently being applied to wheat-based foods is provided. This study concludes that future approaches to food allergen detection will focus on combining multiple tools to rapidly and accurately quantify individual allergens in complex food matrices. Besides, biological modification has many advantages over physical or chemical modification methods in the development of hypoallergenic wheat products, such as enzymatic hydrolysis and fermentation. It is worth noting that using biotechnology to edit wheat allergen genes to produce allergen-free food may be a promising method in the future which could improve the safety of wheat foods and the health of allergy sufferers.


Assuntos
Hipersensibilidade Alimentar , Hipersensibilidade a Trigo , Animais , Alérgenos , Qualidade de Vida , Proteínas , Hipersensibilidade Alimentar/prevenção & controle , Dieta
5.
Front Nutr ; 9: 803440, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35600826

RESUMO

Insoluble dietary fiber (IDF) were isolated from wheat bran (WB) after microbial fermentation with single or mixed strain [Lactobacillus plantarum, Lactobacillus acidophilus, Bacillus subtilis or mixed lactic acid bacteria (L. plantarum and L. acidophilus with ration of 1:1)]. Structure, physicochemical, functional properties, and antioxidant activity of the wheat bran insoluble dietary fiber (W-IDF) modified by fermentation were studied. Fourier transformed infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM) analysis suggested the successful modification of W-IDF. After fermentation with L. plantarum and mixed lactic acid bacteria, the water retention capacity (WRC), oil retention capacity (ORC), and water swelling capacity (WSC) of W-IDF were improved. The sodium cholate adsorption capacity (SCAC), and cation exchange capacity (CEC) of W-IDF modified with L. acidophilus fermentation were significantly increased. Although the cholesterol adsorption capacity (CAC) of W-IDF decreased after modification with probiotic fermentation, nitrite ion adsorption capacity (NIAC), and total phenolic content (TPC) were enhanced. Additionally, W-IDF modified by fermentation with B. subtilis or mixed lactic acid bacteria exhibited superior antioxidant capacity verified by DPPH, ABTS and total reducing power assays. Results manifested that microbial fermentation is a promising methods to modify the W-IDF to provide high-quality functional IDF for food processing and human health management.

6.
BMC Biotechnol ; 22(1): 4, 2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-35039025

RESUMO

BACKGROUND: Petrochemical resources are becoming increasingly scarce, and petroleum-based plastic materials adversely impact the environment. Thus, replacement of petroleum-based materials with new and effective renewable materials is urgently required. RESULTS: In this study, a wheat pentosan-degrading bacterium (MXT-1) was isolated from wheat-processing plant wastewater. The MXT-1 strain was identified using molecular biology techniques. The degradation characteristics of the bacteria in wheat pentosan were analyzed. The results show that wheat pentosan was effectively degraded by bacteria. The molecular weight of fermented wheat pentosan decreased from 1730 to 257 kDa. The pentosan before and after the biological modification was mixed with chitosan to prepare a composite film. After fermentation, the water-vapor permeability of the wheat pentosan film decreased from 0.2769 to 0.1286 g mm (m2 h KPa)-1. Results obtained from the Fourier-transformed infrared experiments demonstrate that the wave number of the hydroxyl-stretching vibration peak of the membrane material decreased, and the width of the peak widened. The diffraction peak of the film shifted to the higher 2θ, as seen using X-ray diffraction. The cross-section of the modified composite membrane was observed via scanning electron microscopy, which revealed that the structure was denser; however, no detectable phase separation was observed. These results may indicate improved molecular compatibility between wheat pentosan and chitosan and stronger hydrogen bonding between the molecules. Given the increased number of short-chain wheat pentosan molecules, although the tensile strength of the film decreased, its flexibility increased after fermentation modification. CONCLUSION: The findings of this study established that the physical properties of polysaccharide films can be improved using strain MXT-1 to ferment and modify wheat pentosan. The compatibility and synergy between pentosan and chitosan molecules was substantially enhanced, and hydrogen bonding was strengthened after biological modification. Therefore, modified pentosan film could be a potential candidate material for edible packaging films.


Assuntos
Quitosana , Petróleo , Amido/química , Triticum , Águas Residuárias
7.
Front Nutr ; 9: 1082671, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36687715

RESUMO

Egg yolk lecithin has physiological activities as an antioxidant, antibacterial, anti-inflammatory, and neurologic, cardiovascular, and cerebrovascular protectant. There are several methods for extracting egg yolk lecithin, including solvent extraction and supercritical extraction. However, changes in extraction methods and functional activity of egg yolk lecithin are a matter of debate. In this review we summarized the molecular structure, extraction method, and functional activity of egg yolk lecithin to provide a good reference for the development of egg yolk lecithin products in the future.

8.
Compr Rev Food Sci Food Saf ; 20(1): 198-224, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33393195

RESUMO

The market trend towards plant-based protein has seen a significant increase in the last decade. This trend has been projected to continue in the coming years because of the strong factors of sustainability and less environmental impact associated with the production of plant-based protein compared to animal, aside from other beneficial health claims and changes in consumers' dietary lifestyles. In order to meet market demand, there is a need to have plant-based protein ingredients that rival or have improved quality and functionality compared to the traditional animal protein ingredients they may replace. In this review article, we present a detailed and concise summary of the functionality challenges of some plant protein ingredients with associated physical, chemical, and biological processing techniques (traditional and emerging technologies) that have been attempted to enhance them. We cataloged the differences between several studies that seek to address the functionality challenges of selected plant-based protein ingredients without overtly commenting on a general technique that addresses the functionality of all plant-based protein ingredients. Additionally, we elucidated the chemistry behind some of these processing techniques and how they modify the protein structure for improved functionality. Although, many food industries are shifting away from chemical modification of proteins because of the demand for clean label product and the challenge of toxicity associated with scale-up of this technique, so physical and biological techniques are widely being adopted to produce a functional ingredient such as texturized vegetable proteins, hydrolyzed vegetable protein, clean label protein concentrates, de-flavored protein isolates, protein flour, and grits.


Assuntos
Proteínas de Plantas , Alimentos de Soja , Animais , Farinha , Proteínas de Vegetais Comestíveis , Paladar
9.
Nanomedicine (Lond) ; 15(18): 1779-1793, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32705940

RESUMO

Aim: To evaluate the biological function of titanium implants coated with cell-derived mineralized extracellular matrix, which mimics a bony microenvironment. Materials & methods: A biomimetic titanium implant was fabricated primarily by modifying the titanium surface with TiO2 nanotubes or sand-blasted, acid-etched topography, then was coated with mineralized extracellular matrix constructed by culturing bone marrow mesenchymal stromal cells. The osteogenic ability of biomimetic titanium surface in vitro and in vivo were evaluated. Results:In vitro and in vivo studies revealed that the biomimetic titanium implant enhanced and accelerated osteogenesis of bone marrow stromal cells by increasing cell proliferation and calcium deposition. Conclusion: By combining surface topography modification with biological coating, the results provided a valuable method to produce biomimetic titanium implants with excellent osteogenic ability.


Assuntos
Osteogênese , Titânio , Biomimética , Diferenciação Celular , Proliferação de Células , Materiais Revestidos Biocompatíveis , Matriz Extracelular , Propriedades de Superfície
10.
Chemosphere ; 256: 127142, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32464362

RESUMO

The development of lignocellulose-based adsorbents for the removal of heavy metals from wastewater has attracted much recent attention. In this work, a high-yield cellulose bacterial strain Comamonas testosteroni FJ17 was evaluated for its capacity to modify rice straw towards increased Cu(II) removal. For optimum modification time (45.5 h), inoculum concentration (1.25%), and rice straw dose (12.6 g L-1) the optimized adsorption capacity was 28.4 mg g-1. After strain FJ17 modification the equilibrium adsorption percentage of rice straw for Cu(II) increased from 6.6 to 27.4% at an initial concentration of 100 mg L-1. This increase was attributed to an increase in rice straw surface modification, leading to improved adsorption ability. SEM-EDS indicated that, following strain FJ17 treatment, the surface of the rice straw became more disintegrated and the specific surface area consequentially increased from 1.9 to 3.7 m2 g-1. FTIR analysis also showed new functional groups (carbonyl) appearing, and CC and CH3CR functionality being enhanced after biomodification. Functional groups associated with the benzene ring, silicified polymer and carbohydrates were all involved in the adsorption process. Adsorption of Cu was well described by the Freundlich isotherm model (R2 > 0.98) where adsorption was endothermic with potential for both chemical and physical interactions to coexist. Reusability experiments showed that the removal efficiency of Cu(II) decreased from 96.9 to 73.2% after five cycles. Overall C.testosteroni-treated rice straw had significant potential as a heavy metal biosorbent.


Assuntos
Comamonas/metabolismo , Cobre/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Celulose , Concentração de Íons de Hidrogênio , Cinética , Lignina/metabolismo , Oryza
11.
Appl Biochem Biotechnol ; 188(4): 965-976, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30740623

RESUMO

The montan resin (MR) is a solid waste produced during the industrial process of refined montan wax from lignite, and usually disposed by landfill and incineration, which easily cause environmental pollution and resource waste. Based its physicochemical properties, our study attempted to modify MR by Bacillus benzoevorans to achieve ecological utilization of MR. As results, the weight loss rate of MR, expressed as modification degree, was found to increase with the increase of B. benzoevorans-incubated time. The apparent oil-water partition coefficient (Kow), used to evaluate the improvement on hydrophilicity of MR, significantly increased (P < 0.01) after modification. IR analysis showed the functional groups of -OH and C=O in modified MR were more than those in MR. Meanwhile, comparison of the chemical changes between MR and modified MR by relatively quantitative analysis of gas chromatography-mass spectrometry (GC-MS) revealed that the content of some chemical components in the latter decreased, and the newly appeared chemical components all had more oxygen-containing functional groups. The bioactivity of the modified MR in agricultural application was evaluated regarding germination and seedling growth of maize seed preliminarly. Compared with the original MR-treated group, the modified MR showed an obvious effect on promoting the growth and germination of maize.


Assuntos
Bacillus/metabolismo , Resinas Sintéticas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Germinação/fisiologia , Plântula/metabolismo , Sementes/metabolismo , Instalações de Eliminação de Resíduos , Zea mays/metabolismo
12.
Toxins (Basel) ; 9(12)2017 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-29261142

RESUMO

Fungi of the genus Fusarium infect cereal crops during the growing season and cause head blight and other diseases. Their toxic secondary metabolites (mycotoxins) contaminate grains. Several dozen toxic compounds produced by fungal pathogens have been identified to date. Type B trichothecenes-deoxynivalenol, its acetyl derivatives and nivalenol (produced mainly by F. graminearum and F. culmorum)-are most commonly detected in cereal grains. "T-2 toxin" (produced by, among others, F. sporotrichioides) belongs to type-A trichothecenes which are more toxic than other trichothecenes. Antagonistic bacteria and fungi can affect pathogens of the genus Fusarium via different modes of action: direct (mycoparasitism or hyperparasitism), mixed-path (antibiotic secretion, production of lytic enzymes) and indirect (induction of host defense responses). Microbial modification of trichothecenes involves acetylation, deacetylation, oxidation, de-epoxidation, and epimerization, and it lowers the pathogenic potential of fungi of the genus Fusarium. Other modifing mechanisms described in the paper involve the physical adsorption of mycotoxins in bacterial cells and the conjugation of mycotoxins to glucose and other compounds in plant and fungal cells. The development of several patents supports the commercialization and wider application of microorganisms biodegrading mycotoxins in grains and, consequently, in feed additives.


Assuntos
Bactérias/metabolismo , Grão Comestível/microbiologia , Contaminação de Alimentos/prevenção & controle , Fungos/metabolismo , Tricotecenos/metabolismo , Fungos/patogenicidade
13.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 52(7): 450-453, 2017 Jul 09.
Artigo em Chinês | MEDLINE | ID: mdl-29972912

RESUMO

During the past three decades, the technology of implant surface modification has already formed well-developed methods including physical and chemical means. However, titanium is a kind of bioinert material, which will directly result in slowly bone-bond with bone tissue after implantation and ultimately reduce the success rate of dental implant surgery. Therefore, the introduction of bioactive substances which can effectively regulate and promote the proliferation of bone cells to modify the titanium implant surface has received tremendous attention in the research of oral implant field. The research of biological modification starts relatively late and it has not formed well-established system yet. The research progress is given in this paper concerning the bioactivators and methods used in biological modification. Furthermore, the current situation as well as the recent developments involving the biological modification of dental implant are also discussed in this review.


Assuntos
Implantação Dentária Endóssea/tendências , Implantes Dentários/tendências , Pesquisa em Odontologia/tendências , Osseointegração , Titânio , Planejamento de Prótese Dentária , Propriedades de Superfície
14.
Sheng Wu Gong Cheng Xue Bao ; 32(6): 738-747, 2016 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-29019183

RESUMO

In this review, we presented the industrial status of biomanufactured polyhydroxyalkanoates (PHA), including poly (3-hydroxybutyrate) (PHB), poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), poly (3-hydroxybutyrate-co-4-hydroxybutyrate) (P3/4HB)), and poly (3-hydroxybutyrate-3-hydroxycaproate) (PHBH). A lot of modification studies, aimed at solving problems of poor thermal stability, narrow processing window and other drawbacks of PHA, are discussed. The properties of PHA can be optimized by using proper modification method, in order to expand its applications.


Assuntos
Biotecnologia , Poli-Hidroxialcanoatos/química , Ácido 3-Hidroxibutírico , Hidroxibutiratos , Poliésteres
15.
J Mater Chem B ; 4(42): 6773-6786, 2016 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-28133536

RESUMO

Bone tissue engineering (BTE) is emerging as a possible solution for regeneration of bone in a number of applications. For effective utilization, BTE scaffolds often need modifications to impart biological cues that drive diverse cellular functions such as adhesion, migration, survival, proliferation, differentiation, and biomineralization. This review provides an outline of various approaches for building bioactive elements into synthetic scaffolds for BTE and classifies them broadly under two distinct schemes; namely, the top-down approach and the bottom-up approach. Synthetic and natural routes for top-down approaches to production of bioactive constructs for BTE, such as generation of scaffold-extracellular matrix (ECM) hybrid constructs or decellularized and demineralized scaffolds, are provided. Similarly, traditional scaffold-based bottom-up approaches, including growth factor immobilization or peptide-tethered scaffolds, are provided. Finally, a brief overview of emerging bottom-up approaches for generating biologically active constructs for BTE is given. A discussion of the key areas for further investigation, challenges, and opportunities is also presented.

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