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1.
Int J Biol Macromol ; 267(Pt 1): 131397, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38582479

RESUMO

This study aimed to develop a multifunctional active composite film to extend the shelf life of minced pork. The composite film was prepared by incorporating zinc-doped grapefruit peel-derived carbon quantum dots (Zn-GFP-CD) into a cellulose nanofiber (CNF) matrix. The resulting film significantly improved UV-blocking properties from 39.0 % to 85.7 % while maintaining the film transparency. Additionally, the CNF/Zn-GFP-CD5% composite film exhibits strong antioxidant activity with ABTS and DPPH radical scavenging activities of 99.8 % and 77.4 %, respectively. The composite film also showed excellent antibacterial activity against both Gram-negative and Gram-positive bacteria. When used in minced pork packaging, the composite films effectively inhibit bacterial growth, maintaining bacterial levels below 7 Log CFU/g after 15 days and sustaining a red color over a 21-day storage period. Additionally, a significant reduction in the lipid oxidation of the minced pork was observed. These CNF/Zn-GFP-CD composite films have a great potential for active food packaging applications to extend shelf life and maintain the visual quality of packaged meat.


Assuntos
Carbono , Celulose , Citrus paradisi , Embalagem de Alimentos , Nanofibras , Pontos Quânticos , Zinco , Pontos Quânticos/química , Nanofibras/química , Celulose/química , Embalagem de Alimentos/métodos , Zinco/química , Citrus paradisi/química , Carbono/química , Antioxidantes/química , Antioxidantes/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Animais , Suínos
2.
Int J Biol Macromol ; 258(Pt 1): 129302, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38262822

RESUMO

A cellulose nanofiber (CNF)/pullulan (PUL) based multifunctional composite film was developed for active packaging applications by incorporating Zn-doped avocado-derived carbon dots (Zn-ACDs). The incorporation of Zn-ACDs improved the interfacial compatibility and produced a dense cross-sectional structure of the composite films. The Zn-ACDs added film showed no significant difference in water vapor permeability and surface hydrophilicity compared to the neat CNF/PUL film, but the tensile strength and elongation at break increased by ~45.4 % and ~64.1 %, respectively. The addition of 5 wt% Zn-ACDs to the CNF/PUL matrix resulted in 100.0 % UV blocking properties, excellent antioxidant activity (100.0 % for ABTS and 68.0 % for DPPH), and complete eradication of foodborne pathogens such as Listeria monocytogenes ATCC 15313 and Escherichia coli O157:H7 after 3 h of exposure. The CNF/PUL composite film with Zn-ACDs applied to the active packaging of chicken and tofu significantly reduced the total growth of aerobic microorganisms without significantly changing the actual color of the packaged chicken and tofu for 9 days at 10°C. This study demonstrates that CNF/PUL composite films with Zn-ACDs are a sustainable and environmentally friendly option for protecting food from microbial contamination.


Assuntos
Glucanos , Nanofibras , Persea , Alimentos de Soja , Animais , Celulose/química , Galinhas , Zinco , Nanofibras/química , Estudos Transversais , Embalagem de Alimentos/métodos
3.
Int J Biol Macromol ; 265(Pt 1): 130760, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462097

RESUMO

Bilayer pouches were fabricated with chitosan (CS)-fish gelatin (FG) mixture containing epigallocatechin gallate (EGCG) deposited over the poly lactic acid (PLA) film through solvent casting and electrospinning techniques. Pickering emulsions (PE) of Asian seabass depot fat oil stabilized by zein colloidal particles were packed in bilayer pouches and stored at 28 ± 2 °C. The PE packed in pouch containing EGCG had higher emulsion and oxidative stability after 30 days of storage as witnessed by the smaller droplet size and lower values of thiobarbituric acid reactive substances, peroxide, conjugated diene and volatile compounds in comparison with control (PE packed in monolayer PLA pouch) (P < 0.05). EGCG incorporated pouch retained more linoleic acid (C18:2 n-6) and linolenic acid (C18:3 n-9) in emulsion than PLA pouch. Therefore, pouch from bilayer PLA/CS-FG films comprising EGCG could serve as active packaging and extended the shelf life of Pickering emulsion.


Assuntos
Catequina/análogos & derivados , Quitosana , Animais , Solventes , Gelatina , Emulsões , Água , Poliésteres , Ácido Láctico , Tamanho da Partícula
4.
Int J Biol Macromol ; 270(Pt 1): 132343, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38750841

RESUMO

Color indicator films incorporating aronia extract powder (AEP) and biopolymers like agar, carrageenan, and cellulose nanofiber (CNF) were developed to monitor kimchi freshness. AEP-containing films showed strong UV-barrier properties, and reduced light transmittance by 99.12 % for agar, 98.86 % for carrageenan, and 98.67 % for CNF-based films. All AEP-films exhibited high sensitivity to pH changes and vapor exposure to ammonia and acetic acid. Color change notably influenced by the polymer type, particularly evident with ammonia vapor exposure, especially in the AEP/carrageenan film. The chemical structure and thermal stability of the biopolymers remained unchanged after AEP-addition. Tensile strength increased by 24.2 % for AEP/CNF but decreased by 19.4 % for AEP/agar and 24.3 % for AEP/carrageenan films. AEP-containing films displayed strong antioxidant activity, with 99 % free radical scavenging in ABTS and ~ 80 % in DPPH assays. Alkalized AEP-indicator films were more effective in detecting color changes during kimchi packaging tests. Among the labels, alkalized AEP/agar film showed the most obvious color change from green-gray (fresh kimchi, pH 5.5, acidity 0.48 %) to pale brown (optimal fermentation, pH 4.6, acidity 0.70 %), and pale violet-brown (over-fermented, pH 3.80, acidity 1.35 %). Alkalized AEP-indicator films offer promising real-time detection of packed fermented foods like kimchi.


Assuntos
Ágar , Carragenina , Celulose , Colorimetria , Embalagem de Alimentos , Nanofibras , Extratos Vegetais , Carragenina/química , Nanofibras/química , Ágar/química , Celulose/química , Colorimetria/métodos , Embalagem de Alimentos/métodos , Extratos Vegetais/química , Antioxidantes/química , Antioxidantes/análise , Resistência à Tração , Cor , Concentração de Íons de Hidrogênio
5.
Int J Biol Macromol ; 234: 123679, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36801227

RESUMO

Curcumin-encapsulated Pickering emulsion (Cur-PE) was successfully prepared using cellulose nanocrystals (CNCs)-whey protein isolate (WPI) complex as a stabilizer to control the size and stability of the Cur-PE. Firstly, needle-like CNCs were prepared by acid hydrolysis, and the mean particle size, polydispersity index (PDI), zeta potential, and aspect ratio of the CNCs were 100.7 nm, 0.32, -43.6 mV, and 20.8, respectively. The Cur-PE-C0.5W0.1, prepared with 0.5 wt% CNCs and 0.1 wt% WPI at pH 2, had a mean droplet size of 230.0 nm, PDI of 0.275, and zeta potential of +53.5 mV. The Cur-PE-C0.5W0.1 prepared at pH 2 exhibited the highest stability during storage for 14 days. FE-SEM revealed that the droplets of the Cur-PE-C0.5W0.1 prepared at pH 2 were spherical and fully covered by CNCs. The adsorption of CNCs at the oil-water interface increases the encapsulation efficiency (89.4 %) of curcumin in the Cur-PE-C0.5W0.1 and protects curcumin from pepsin digestion in the gastric phase. However, the Cur-PE-C0.5W0.1 was sensitive to release curcumin in the intestine phase. The CNCs-WPI complex developed in this study could serve as a promising stabilizer to make Pickering emulsions stable at pH 2 for the encapsulation and delivery of curcumin to the expected target area.


Assuntos
Curcumina , Nanopartículas , Emulsões/química , Curcumina/química , Proteínas do Soro do Leite/química , Celulose/química , Digestão , Excipientes , Nanopartículas/química , Lipídeos , Tamanho da Partícula
6.
Sci Total Environ ; 878: 163156, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37003328

RESUMO

The environmental impact associated with fossil fuel-based polymers has paved the way to explore biopolymer-based plastics, their properties, and their applications. Bioplastics are polymeric materials that are greatly interesting due to their eco-friendlier and non-toxic nature. In recent years, exploring the different sources of bioplastics and their applications has become one of the active research areas. Biopolymer-based plastics have applications in food packaging, pharmaceuticals, electronics, agricultural, automotive and cosmetic sectors. Bioplastics are considered safe, but there are several economic and legal challenges to implementing them. Hence, this review aims to i) outline the terminology associated with bioplastics, its global market, major sources, types and properties of bioplastics, ii) discuss the major bioplastic waste management and recovery options, iii) provide the major standards and certifications regarding bioplastics, iv) explore the various country-wise regulations and restrictions associated with bioplastics, and v) enumerate the various challenges and limitations associated with bioplastics and future directions. Therefore, providing adequate knowledge about various bioplastics, their properties and regulatory aspects can be of great importance in the industrialization, commercialization and globalization of bioplastics to replace petroleum-based products.


Assuntos
Plásticos , Polímeros , Biopolímeros , Embalagem de Alimentos , Certificação
7.
Int J Biol Macromol ; 249: 126040, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37541465

RESUMO

Innovative active and pH-colorimetric composite films were fabricated from gelatin/poly(vinyl alcohol) (Gel/PVA) integrated with copper-based metal-organic frameworks (Cu-MOFs) and red cabbage anthocyanin (RCA). The incorporation of Cu-MOFs improved the tensile strength, water resistance, and UV shielding properties of the developed composite films. The addition of anthocyanins and 3 wt% Cu-MOFs endowed the polymer matrix with excellent antioxidant (100 % against ABTS and DPPH radicals) and antibacterial (against Gram-positive and Gram-negative foodborne pathogenic bacteria) functions. The fabricated composite films exhibited significant color change at alkaline conditions of pH 7-12 and a marked color change upon exposure to ammonia. The designed indicator films used for shrimp freshness tracking and a visual color change from pink (for fresh shrimp) to green (for spoiled shrimp) was observed during storage at 28 °C for 24 h. The potential applications of the engineered composite films were studied by shrimp packaging, and the quality parameters of packaged samples were monitored during storage. The synergistic effects of adding anthocyanins and MOF nanostructures works for better product freshness preservation and responds well to shrimp spoilage level, introducing novel active and intelligent packaging options for practical smart packaging applications.


Assuntos
Embalagem de Alimentos , Estruturas Metalorgânicas , Álcool de Polivinil , Antocianinas , Cobre , Gelatina , Concentração de Íons de Hidrogênio
8.
Int J Biol Macromol ; 242(Pt 3): 124905, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37224902

RESUMO

Five natural pigments including water-soluble [butterfly pea (BP), red cabbage (RC), and aronia (AR)] and alcohol-soluble [shikonin (SK) and alizarin (ALZ)] were extracted, characterized, and loaded onto cellulose for preparing pH-sensitive indicators. The indicators were tested for their color response efficiency, gas sensitivity, response to lactic acid, color release, and antioxidant activity. Cellulose-water soluble indicators showed more obvious color changes than alcohol-soluble indicators in lactic acid solution and pH solutions (1-13). All cellulose-pigment indicators exhibited prominent sensitivity to ammonia compared to acidic vapor. Antioxidant activity and release behavior of the indicators were influenced by pigment type and simulants. Kimchi packaging test was carried out using original and alkalized indicators. The alkalized indicators were more effective in showing visible color changes during kimchi storage than the original indicators, and cellulose-ALZ displayed the most distinct color change from violet (fresh kimchi, pH 5.6, acidity 0.45 %) to gray (optimum fermented kimchi, pH 4.7, acidity 0.72 %), and to yellow (over fermented kimchi, pH 3.8, acidity 1.38 %) which followed by BP, AR, RC, SK respectively. The findings of the study suggest that the alkalization method could be used to show noticeable color changes in a narrow pH range for application with acidic foods.


Assuntos
Brassica , Alimentos Fermentados , Celulose/química , Embalagem de Alimentos/métodos , Antioxidantes , Concentração de Íons de Hidrogênio , Ácidos , Ácido Láctico , Água
9.
ACS Appl Mater Interfaces ; 15(16): 20435-20443, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37053446

RESUMO

Face masks are increasingly important in the battle against infectious diseases and air pollution. Nanofibrous membranes (NFMs) are promising filter layers for removing particulate matter (PM) without restricting air permeability. In this study, tannic-acid-enriched poly(vinyl alcohol) (PVA-TA) NFMs were fabricated by electrospinning PVA solutions containing large amounts of tannic acid (TA), a multifunctional polyphenol compound. We were able to prepare uniform electrospinning solution without coacervate formation by inhibiting the robust hydrogen bonding between PVA and TA. Notably, the NFM maintained its fibrous structure even under moist conditions after heat treatment without the use of a cross-linking agent. Further, the mechanical strength and thermal stability of the PVA NFM were improved by the introduction of TA. The functional PVA NFM with a high TA content showed excellent UV-shielding (UV-A: 95.7%, UV-B: 100%) and antibacterial activity against Escherichia coli (inhibition zone: 8.7 ± 1.2 mm) and Staphylococcus aureus (inhibition zone: 13.7 ± 0.6 mm). Moreover, the particle filtration efficiency of the PVA-TA NFM for PM0.6 particles was 97.7% at 32 L min-1 and 99.5% at 85 L min-1, indicating excellent filtration performance and a low pressure drop. Therefore, the TA-enriched PVA NFM is a promising mask filter layer material with excellent UV-blocking and antibacterial properties and has the potential for various practical applications.


Assuntos
Nanofibras , Álcool de Polivinil , Álcool de Polivinil/química , Nanofibras/química , Máscaras , Antibacterianos/farmacologia , Antibacterianos/química , Filtração , Material Particulado , Taninos
10.
Int J Biol Macromol ; 213: 381-393, 2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35654221

RESUMO

Aronia or black chokeberry (Aronia melanocarpa), cellulose nanocrystals (CNCs), and grapefruit seed extract (GSE) were used for the preparation of multifunctional polyvinyl alcohol/chitosan (PVA/CS) composite films with pH-sensitivity, antimicrobial, antioxidant, and UV-barrier properties. Aronia extract showed total phenolic content of 297 ± 0.5 µg GAE/mg aronia extract, potent antioxidant activity, and high color-response efficiency. Isolated CNCs showed a needle-like structure with a length of 470 nm and a width of 35 nm. The tensile strength of the PVA/CS composite film increased by 74% after the incorporation of CNCs, whereas the film flexibility was enhanced by 75% after adding GSE. The PVA/CS-A (aronia extract) composite film showed a significant color change at different pHs and potent antioxidant activity. At the same time, the PVA/CS-G (GSE) showed the highest antimicrobial activity against Escherichia coli (Gram-negative) and Listeria monocytogenes (Gram-positive) bacteria. The PVA/CS-CGA composite film, reinforced with CNCs/GSE/Aronia extract, showed the highest UV-barrier (95.5%), highest antioxidant activity (95%), potent antimicrobial activity, pH-sensitivity, lowest water vapor permeability (WVP), and desirable mechanical properties. The multifunctional properties of the produced composite films encourage their use as active and intelligent food packaging films to extend shelf life and monitor food quality.


Assuntos
Anti-Infecciosos , Quitosana , Nanopartículas , Photinia , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Celulose/química , Quitosana/química , Citrus paradisi , Escherichia coli , Embalagem de Alimentos , Bactérias Gram-Positivas , Nanopartículas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Álcool de Polivinil/química
11.
Int J Biol Macromol ; 194: 736-745, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34838863

RESUMO

Poly (vinyl alcohol) (PVA) films with high transparency, UV-barrier, antioxidant, and antimicrobial properties were prepared using oregano essential oil (OEO) and cinnamon essential oil (CEO) Pickering emulsions. The effect of Pickering emulsion type and concentration on the PVA film properties was studied. Cellulose nanocrystals (CNCs) were used as a natural stabilizer to prepare OEO and CEO Pickering emulsions. Both emulsions showed spherical droplets with diameters of 155-291 nm, zeta potential of -36.2 to -49.6 mV, minimum inhibition concentration of 6.25-12.5 µL/mL, and inhibition zone of 40-65 mm, depending on oil type. Morphology and FTIR analysis showed that OEO and CEO Pickering emulsions were compatible with the PVA matrix. The UV-transmittance of PVA films decreased from 77.3% to 30.4% and 2.0% without sacrificing the transparency after adding OEO and CEO Pickering emulsions, respectively. Antimicrobial results showed that E. coli was more sensitive to CEO, while S. aureus was sensitive to OEO Pickering emulsion. PVA/CEO film displayed higher properties than PVA/OEO film.


Assuntos
Celulose/química , Emulsões/química , Nanopartículas/química , Óleos Voláteis , Antibacterianos/química , Antibacterianos/farmacologia , Cinnamomum zeylanicum/metabolismo , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Origanum/metabolismo
12.
Food Chem ; 392: 133306, 2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-35636193

RESUMO

Curcumin-nanostructured lipid carrier-loaded oleogels (Cur-NLC-OGs) have been developed with biopolymer cryogels as an efficient delivery system to overcome the extremely low water solubility and instability of curcumin. The effect of NLC and biopolymer types on the encapsulation and release of curcumin from Cur-OGs was investigated. Alginate, carboxymethyl cellulose (CMC), and pectin solutions were firstly freeze dried to make biopolymer cryogels and they were mixed with Cur and Cur-NLC to obtain stable and self-standing Cur-OGs and Cur-NLC-OGs, respectively. As compared to Cur-OGs, Cur-NLC-OGs had higher encapsulation efficiency and showed slower release of curcumin under acidic condition. Although Cur-NLC affected the rapid release of free fatty acids, the Cur-NLC-OGs prepared with CMC cryogel was most efficient in delaying lipid digestion. Overall, NLC and CMC-based OGs could be effectively used to improve encapsulation efficiency and control lipolysis of lipid droplets. These results will be advantageous for the development of oleogels with desirable functionality.


Assuntos
Curcumina , Biopolímeros , Criogéis , Digestão , Portadores de Fármacos , Lipídeos , Compostos Orgânicos , Tamanho da Partícula
13.
Int J Biol Macromol ; 209(Pt A): 895-903, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35447259

RESUMO

W/O/W double emulsion-based iron-solid lipid nanoparticles (Fe-SLNs) and water-soluble chitosan-coated Fe-SLNs (WSC-Fe-SLNs) were developed to increase the bioaccessibility and stability of iron. Fe-SLNs exhibited a small diameter (158.17 ± 0.72 nm) and adequate zeta potential (-34.31 ± 0.41 mV) to maintain stable dispersion. The coating with WSC resulted in an increase in particle diameter (up to 226.13 ± 1.97 nm) and change of zeta potential to positive value (+47.83 ± 1.24 mV) because of the amine groups of chitosan. The lipid peroxidation of the Fe-SLNs and WSC-Fe-SLNs was substantially lower than that of pure iron. Both Fe-SLNs and WSC-Fe-SLNs were also able to protect the encapsulated iron in simulated gastric fluid, while effectively releasing almost 80% of the iron in simulated intestinal fluid. The Fe-SLNs and WSC-Fe-SLNs showed a great potential as functional materials to apply to various food industries through enhancement of physical stability and bioaccessibility of the encapsulated iron.


Assuntos
Quitosana , Nanopartículas , Portadores de Fármacos , Emulsões , Ferro , Lipídeos , Lipossomos , Tamanho da Partícula , Água
14.
Int J Biol Macromol ; 208: 520-529, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35337911

RESUMO

Curcumin-loaded nanostructured lipid carriers (Cur-NLCs)-based hydroxypropyl methylcellulose (HPMC) oleogels (Cur-NLCs-HPMC-OGs) were fabricated using a cryogel template. The effect of the HPMC viscosity grade on the oleogel characteristics and in situ intestinal absorption were examined. Highly stable Cur-NLCs were prepared with a mean particle size of 314 nm and polydispersity index of 0.275. Cur-NLCs affected the creamy texture of self-standing Cur-NLCs-HPMC-OGs. The Cur-NLCs were tightly packed as oil droplets in the network of HPMC. However, a high viscosity of HPMC-4000 led to a greater ability to entrap and prevent droplet coalescence compared to a low viscosity of HPMC-400. NLCs promoted the release of free fatty acids during in vitro lipid digestion, whereas HPMC-4000 maintained the strength and durability of oleogels against mechanical and enzymatic breakdown. The in situ loop results revealed higher curcumin absorption by Cur-NLCs-HPMC-OGs than by Cur-HPMC-OGs. HMPC-4000 showed slightly higher curcumin absorption compared to HPMC-400.


Assuntos
Curcumina , Animais , Digestão , Portadores de Fármacos , Derivados da Hipromelose , Absorção Intestinal , Lipídeos , Compostos Orgânicos , Tamanho da Partícula , Ratos
15.
Water Res ; 202: 117417, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34271456

RESUMO

The effectiveness of traditional drinking water treatment plants for the removal of Microplastics (MPs) in the size range of tens of micrometers is currently uncertain. This study investigated the behavior and removal efficiency of four different sized polystyrene MPs (10-90 µm in diameter) in a simulated cascade of coagulation/sedimentation, sand filtration, and UV-based oxidation over technically relevant time frames. In the coagulation and sand filtration steps, the larger the MP size, the better it was removed. The coagulant type and water characteristics (i.e., pH and the presence of natural organic matter) influenced the coagulation efficiency for MPs. X-ray microcomputed tomography technique and two-site kinetic modeling were used to identify the mechanisms involved in sand filtration. The MPs > 20 µm could be completely retained in sand by straining, while the attachment to the sand surface was likely responsible for the retention of MPs < 20 µm. However, approximately 16% of 10 µm MPs injected passed through the sand, which were further fragmented by UV oxidation. UV/H2O2 treatment promoted the MP fragmentation and chemical leaching more significantly than UV treatment, resulting in a higher toxicity for UV/H2O2-treated water. Our findings pave the way for deeper understanding of how MPs behave and transform in a sequential drinking water treatment process.


Assuntos
Água Potável , Poluentes Químicos da Água , Purificação da Água , Peróxido de Hidrogênio , Microplásticos , Plásticos , Poluentes Químicos da Água/análise , Microtomografia por Raio-X
16.
Appl Microbiol Biotechnol ; 81(5): 865-74, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18773201

RESUMO

To search for new cold-active lipases, a metagenomic library was constructed using cold-sea sediment samples at Edison Seamount and was screened for lipolytic activities by plating on a tricaprylin medium. Subsequently, a fosmid clone was selected, and the whole sequence of 36 kb insert of the fosmid clone was determined by shotgun sequencing. The sequence analysis revealed the presence of 25 open reading frames (ORF), and ORF20 (EML1) showed similarities to lipases. Phylogenetic analysis of EML1 suggested that the protein belonged to a new family of esterase/lipase together with LipG. The EML1 gene was expressed in Escherichia coli, and purified by metal-chelating chromatography. The optimum activity of the purified EML1 (rEML1) occurred at pH 8.0 and 25 degrees C, respectively, and rEML1 displayed more than 50% activity at 5 degrees C. The activation energy for the hydrolysis of olive oil was determined to be 3.28 kcal/mol, indicating that EML1 is a cold-active lipase. rEML1 preferentially hydrolyzed triacylglycerols acyl-group chains with long chain lengths of > or = 8 carbon atoms and displayed hydrolyzing activities toward various natural oil substrates. rEML1 was resistant to various detergents such as Triton X-100 and Tween 80. This study represents an example which developed a new cold-active lipase from a deep-sea sediment metagenome.


Assuntos
Sedimentos Geológicos/microbiologia , Lipase/genética , Lipase/metabolismo , Caprilatos/metabolismo , Cromatografia de Afinidade , Clonagem Molecular , Inibidores Enzimáticos/farmacologia , Estabilidade Enzimática , Escherichia coli , Expressão Gênica , Concentração de Íons de Hidrogênio , Lipase/química , Dados de Sequência Molecular , Octoxinol/farmacologia , Azeite de Oliva , Filogenia , Óleos de Plantas/metabolismo , Polissorbatos/farmacologia , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Temperatura , Triglicerídeos/metabolismo
17.
J Food Sci ; 81(2): N494-501, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26766628

RESUMO

Nanosuspensions (NSs) were fabricated to enhance water solubility, dissolution rate, and oral adsorption of water insoluble curcumin using sonoprecipitation method. As a good stabilizer, d-α-Tocopherol polyethylene glycol 1000 succinate (TPGS) was used to improve the stability of curcumin-TPGS NSs (Cur-TPGS NSs). Ultrasonic homogenization (UH) could effectively enhance the solubility of curcumin and to produce homogeneous NSs with small particle sizes. Water solubility of curcumin was significantly improved from 0.6 µg/mL in pure water to 260 µg/mL in the mixture of curcumin and TPGS (1:10) with UH treatment. The mean particle size of Cur-TPGS NSs was decreased significantly after UH and maintained between 208 and 246 nm. Lyophilized powder of Cur-TPGS NSs was dissolved about 91.08% whereas the pristine curcumin powder was dissolved only 6.5% at pH 7.4. This study showed a great potential of Cur-TPGS NSs as a good nano-formulation of curcumin with enhanced solubility and improved oral adsorption.


Assuntos
Curcuma/química , Curcumina/química , Nanotecnologia , Tamanho da Partícula , Vitamina E/análogos & derivados , Química Farmacêutica/métodos , Cristalização , Estabilidade de Medicamentos , Polietilenoglicóis/química , Pós , Solubilidade , Vitamina E/química , alfa-Tocoferol/química
18.
J Food Sci ; 81(3): N745-53, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26807662

RESUMO

Curcumin nanoemulsions (Cur-NEs) were developed with various surfactant concentrations by using high pressure homogenization and finally applied to the commercial milk system. Characterization of Cur-NEs was performed by measuring the droplet size and polydispersity index value at different Tween 20 concentrations. The morphology of the Cur-NEs was observed by confocal laser scanning microscopy and transmission electron microscopy. Antioxidant activity and in vitro digestion ability were tested using 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, pH-stat method, and thiobarbituric acid reactive substances assays. Cur-NEs were found to be physically stable for 1 mo at room temperature. The surfactant concentration affects particle formation and droplet size. The mean droplet size decreased from 122 to 90 nm when surfactant concentration increased 3 times. Cur-NEs had shown an effective oxygen scavenging activity. Cur-NEs-fortified milk showed significantly lower lipid oxidation than control (unfortified) milk and milk containing curcumin-free nanoemulsions. These properties make Cur-NEs suitable systems for the beverage industry.


Assuntos
Antioxidantes/química , Curcuma/química , Curcumina/química , Emulsões/química , Manipulação de Alimentos/métodos , Peroxidação de Lipídeos/efeitos dos fármacos , Leite/química , Animais , Antioxidantes/farmacologia , Disponibilidade Biológica , Compostos de Bifenilo/metabolismo , Curcumina/farmacologia , Dieta , Digestão , Humanos , Técnicas In Vitro , Oxirredução , Picratos/metabolismo , Polissorbatos/química , Espécies Reativas de Oxigênio/metabolismo , Solubilidade , Tensoativos/química
19.
Environ Int ; 85: 292-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26453819

RESUMO

Human biomonitoring is a valid method to determine exposure, identify time trends, and monitor the effects of restrictions and measures. To characterize the recent exposure of Germans to persistent or emerging substances, we analyzed 4 dechloranes, 33 polychlorinated naphthalenes (PCNs), and 3 cyclic volatile methyl siloxanes (cVMS) in 42 plasma samples. The samples were collected from blood donors on a random selection. The median values of both Dechlorane Plus (DDC-CO) isomers were 1.23ng/gl.w. for anti- and 0.77ng/gl.w. for syn-DDC-CO. The two other dechloranes were found at lower levels. The median level of ∑-PCNs was 575pg/gl.w. (range: 101-1406pg/gl.w.). On average, the levels of PCNs in plasma were dominated by the congeners CN73, CN66/67, and CN51, which were responsible for approximately 71% of the total amount of PCNs. The cVMS octa-, deca-, and dodecamethylcyclotetrasiloxane could be determined in only some samples, with maximum values of 0.73, 0.48, and 0.79µg/l, respectively. Regarding dechloranes, our results are similar to those from other western countries but slightly lower than results from China. The levels of PCNs in German blood are similar to those observed in the U.S.A., but considerably lower than those reported for Korea. Using a preliminary TEF (toxic equivalency factor), the mean TEQ of the 9 quantifiable PCNs in Germany was low (0.36pg TEQ/gl.w.). The PCN levels in our study group are lower compared to previous studies.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/sangue , Hidrocarbonetos Clorados/sangue , Naftalenos/sangue , Siloxanas/análise , Compostos Orgânicos Voláteis/sangue , Adulto , Poluentes Ambientais/química , Alemanha , Humanos , Hidrocarbonetos Clorados/química , Estrutura Molecular , Naftalenos/química , Siloxanas/química , Compostos Orgânicos Voláteis/química
20.
J Agric Food Chem ; 61(46): 11119-26, 2013 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-24175657

RESUMO

Chitosan-coated curcumin nanoliposomes (CS-Cur-NLs) were fabricated by the ethanol injection method (EIM), and their physicochemical properties were compared with the properties of those fabricated by the dry thin film method (DTFM). The mean size and zeta potential of CS-Cur-NLs gradually increased with CS concentration. The encapsulation efficiency of Cur-NLs prepared by EIM was 54.70%, which was significantly improved compared to that (42.60%) of Cur-NLs prepared by DTFM. Further improvement of encapsulation efficiency was attained (up to 64.93%) by EIM with 0.1% CS coating. The mucoadhesive property of Cur-NLs improved from 33.60 to 56.47% with CS coating. The results indicate that the encapsulated curcumin will show prolonged adsorption in the gastrointestinal tract because of higher mucoadhesion. Thus, EIM can be considered to be effective for food-grade delivery carriers with higher encapsulation efficiency and absence of harmful solvents. EIM-generated CS-Cur-NLs showed higher bioavailability, with enhanced high mucoadhesive property, storage stability, and encapsulation efficiency.


Assuntos
Quitosana/química , Curcumina/química , Portadores de Fármacos/química , Lipossomos/química , Nanopartículas/química , Disponibilidade Biológica , Curcumina/farmacologia , Estabilidade de Medicamentos , Tamanho da Partícula
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