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1.
Environ Res ; 252(Pt 1): 118252, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38320716

RESUMO

To effectively remove tannic acid (TA) from wastewater, using green and natural materials has attracted increasing attention. Inspired by Galla Chinensis (GC) with high content of TA, this study synthesized a biomimetic porous adsorbent to mimic the GC structure using dialdehyde tapioca starch (DTS) and gelatin (GL). The TA adsorption performance and mechanism of synthetic porous material were investigated. Results revealed that the porous material exhibited a maximum TA adsorption capacity of 1072.01 mg/g, along with a high removal rate of 95.16% under the conditions of a DTS-GL mass ratio of 1:1, DTS aldehyde content of 48.16%, a solid content of 5%, and a pH of 2 at 25 °C. The adsorption of TA by DTS was not affected by water-soluble cationic and anion. The adsorption kinetics of TA on the porous material followed the pseudo-second-order model, and this Langmuir adsorption model (R2 = 0.9954) which were well described the adsorption of TA by the material, indicating that the adsorption primarily occurred in a monolayer. FTIR, XRD, DSC, TG, XPS, and SEM-EDS were employed to characterize the structure characteristics of the porous material. The cross-linking between DTS and GL by Schiff base reaction imparted a chemical structure could absorb TA by hydrogen bonding. The TA desorption rates of in 30% acetone and 40% ethanol solutions were 88.76% and 91.03%, respectively. The porous material prepared by the GC-inspired approach holds promise as an ideal choice for loading polyphenolic compounds and provides a new perspective for the design and application of bioinspired engineering materials.


Assuntos
Materiais Biomiméticos , Taninos , Águas Residuárias , Poluentes Químicos da Água , Taninos/química , Águas Residuárias/química , Adsorção , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Porosidade , Materiais Biomiméticos/química , Gelatina/química , Purificação da Água/métodos , Manihot/química , Eliminação de Resíduos Líquidos/métodos , Cinética
3.
Foods ; 12(19)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37835219

RESUMO

In this study, we addressed various challenges associated with the consumption of functional lipids from the Ericerus pela (Chavannes), including unfavorable taste, insolubility in water, difficulty in oral intake, low bioavailability, and low psychological acceptance. Our study focused on the microencapsulation of policosanol, the key active component of insect wax, which is a mixture of functional lipids secreted by the Ericerus pela (Chavannes). We developed two innovative policosanol products, microcapsules, and effervescent tablets, and optimized their preparation conditions. We successfully prepared microcapsules containing insect wax-derived policosanol using the spray-drying method. We achieved 92.09% microencapsulation efficiency and 61.67% powder yield under the following conditions: maltodextrin, starch sodium octenyl succinate, and (2-hydroxy)propyl-ß-cyclodextrin (HPßCD) at a ratio of 1:1:1, core-to-wall materials at a ratio of 1:10, 15% solid content, spray dryer feed temperature at 60 °C, inlet air temperature at 140 °C, and hot-air flow rate at 0.5 m3/min. The microcapsules exhibited a regular spherical shape with a minimal water content (1.82%) and rapid dispersion in water (within 143.5 s). These microcapsules released policosanol rapidly in simulated stomach fluid. Moreover, effervescent tablets were prepared using the policosanol-containing microcapsules. The tablets showed low friability (0.32%), quick disintegration in water (within 99.5 s), and high bubble volume. The microcapsules and effervescent tablets developed in this study presented effective solutions to the insolubility of policosanol in water. These products were portable and offered customizable tastes to address the psychological discomfort related to insect-based foods, thus providing a novel strategy for the consumption and secondary processing of insect lipids.

4.
ACS Appl Mater Interfaces ; 15(37): 43294-43308, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37695271

RESUMO

Developing safe and effective wound dressings that address the complexities of wound healing is an ongoing goal in biomaterials research. Inspired by the shield used to protect lac insects, we have designed and developed a type of bioactive shellac-based wound dressing in this paper. The dressing exhibited a high adhesion energy of 146.6 J·m-2 in porcine skin and showed a reversible binding due to its pH sensitivity. Meanwhile, a novel "shellac-like" compound, n-octacosanol gallate ester, has been synthesized and added to the dressing to improve its antibacterial and blood coagulation properties. The novel shellac-based dressing could be sprayed to form a sticky film within 70 s for rapid hemostasis and wound sealing, which could be conveniently applied to various wounds on extensible body parts. In addition, the shellac-based dressing can actively promote the healing of a full-thickness wound in the skin of mice. We also used molecular dynamics simulations to investigate the interactions between the shellac molecule and the phospholipid bilayer and attempted to show that the shellac molecule was beneficial for wound healing. This work provides a novel and practical bioinspired wound dressing with significant properties, facile preparation, and ease of use, which is an interesting alternative to its traditional counterparts.


Assuntos
Pele , Cicatrização , Suínos , Animais , Camundongos , Resinas Vegetais , Bandagens
5.
Biotechnol Adv ; 68: 108236, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37586543

RESUMO

Microalgae are microorganisms capable of producing bioactive compounds using photosynthesis. Microalgae contain a variety of high value-added natural pigments such as carotenoids, phycobilins, and chlorophylls. These pigments play an important role in many areas such as food, pharmaceuticals, and cosmetics. Natural pigments have a health value that is unmatched by synthetic pigments. However, the current commercial production of natural pigments from microalgae is not able to meet the growing market demand. The use of metabolic engineering and synthetic biological strategies to improve the production performance of microalgal cell factories is essential to promote the large-scale production of high-value pigments from microalgae. This paper reviews the health and economic values, the applications, and the synthesis pathways of microalgal pigments. Overall, this review aims to highlight the latest research progress in metabolic engineering and synthetic biology in constructing engineered strains of microalgae with high-value pigments and the application of CRISPR technology and multi-omics in this context. Finally, we conclude with a discussion on the bottlenecks and challenges of microalgal pigment production and their future development prospects.


Assuntos
Engenharia Metabólica , Microalgas , Microalgas/genética , Microalgas/metabolismo , Biologia Sintética , Carotenoides/metabolismo , Biotecnologia
6.
Mol Biol Rep ; 50(6): 5425-5438, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37101007

RESUMO

Since cells are the basic structural and functional units of organisms, the detection or quantitation of cells is one of the most common basic problems in life science research. The established cell detection techniques mainly include fluorescent dye labeling, colorimetric assay, and lateral flow assay, all of which employ antibodies as cell recognition elements. However, the widespread application of the established methods generally dependent on antibodies is limited, because the preparation of antibodies is complicated and time-consuming, and unrecoverable denaturation is prone to occur with antibodies. By contrast, aptamers that are generally selected through the systematic evolution of ligands by exponential enrichment can avoid the disadvantages of antibodies due to their controllable synthesis, thermostability, and long shelf life, etc. Accordingly, aptamers may serve as novel molecular recognition elements like antibodies in combination with various techniques for cell detection. This paper reviews the developed aptamer-based cell detection methods, mainly including aptamer-fluorescent labeling, aptamer-isothermal amplification assay, electrochemical aptamer sensor, aptamer-based lateral flow analysis, and aptamer-colorimetric assay. The principles, advantages, progress of application in cell detection and future development trend of these methods were specially discussed. Overall, different assays are suitable for different detection purposes, and the development of more accurate, economical, efficient, and rapid aptamer-based cell detection methods is always on the road in the future. This review is expected to provide a reference for achieving efficient and accurate detection of cells as well as improving the usefulness of aptamers in the field of analytical applications.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Aptâmeros de Nucleotídeos/química , Corantes Fluorescentes , Ligantes , Anticorpos/química , Tecnologia , Técnicas Biossensoriais/métodos
7.
Environ Technol ; : 1-7, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36727477

RESUMO

ABSTRACTLithium cobalt oxide (LCO) has been employed as cathode material for 40 years. However, the low solubility of LCOs in water and strong electrostatic force and H-bonding between the LCOs particles limited the use of the aqueous binders in the LCO system. We report a feasible and universal approach to fabricating a complex cathode of LCO and reduced graphene oxide (RGO). Tannic acid (TA) could simultaneously disperse LCO and RGO particles. Meanwhile, the branched polyphenol TA acts as a 'bridge' molecule for connecting the LCO and RGO, confirmed by the SEM test. The rheology properties of the PVDF slurry of cathode materials (LCO, LCO/, RGO, and TA/LCO/RGO) were also determined. It could be found that the TA could act as a crosslinking agent for the LCO and RGO particles, increasing the viscosity and storage modulus of the slurry. The cell employed the TA/LCO/RGO slurry as the cathode material, have a higher areal capacity, and had a higher redox potential than employed LCO/RGO and LCO as cathode materials, all of which could be attributed to the addition of the TA. This green molecule can be used to fabricate environmentally friendly and possibly biodegradable electrochemical energy storage devices.

8.
J Hazard Mater ; 449: 131043, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-36827721

RESUMO

Here, to give early waring for harmful algal blooms caused by Prorocentrum minimum, we reported a simple and rapid colorimetric assay that is named aptamer-gold nanoparticles (GNPs) based colorimetric assay (AGBCA). The GNPs maintain a dispersed state and have a strong characteristic absorption peak at 520 nm. With the addition of NaCl, the stability of the solution will be destroyed and the dispersed GNPs will aggregate. Therefore, the characteristic absorption peak of the GNPs solution will change from 520 nm to 670 nm. Aptamers can be adsorbed on the surface of GNPs, effectively preventing the aggregation of GNPs. In the presence of P. minimum, aptamers will specifically bind to P. minimum, causing the dissociation of the aptamers from GNPs. Consequently, the GNPs will aggregate in the NaCl solution, corresponding to a new absorption peak at 670 nm. A linear relationship between the absorbance ratio variation (ΔA670/A520) and the P. minimum concentration was observed in the concentration range of 1 × 102 - 1 × 107 cells mL-1, with a low detection limit of 8 cells mL-1. The developed AGBCA is characterized by simplicity, strong specificity, and high sensitivity and is thus promising for the quantitative detection of P. minimum in natural samples.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Ouro , Colorimetria/métodos , Cloreto de Sódio , Técnicas Biossensoriais/métodos
9.
Environ Res ; 220: 115099, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36563978

RESUMO

Harmful algal blooms (HABs) caused by Prorocentrum minimum have seriously posed economic losses and ecological disasters. To reduce these losses, aptamers are used as a new molecular probe to establish rapid methods. Herein, to improve the affinity and application of aptamers in the detection of harmful algae, the optimization was performed on the previously reported aptamers against P. minimum. First, a total of seven candidate aptamers, including three truncated aptamers (TA1, TA2 and TA3) and four mutant aptamers (MA1, MA2, MA3 and MA4), were obtained by truncation and G-quadruplex (GQ)-forming mutation. Next, the specificity and affinity test by flow cytometry revealed that except for TA1 and TA2, all of the candidate aptamers are specific with the equilibrium dissociation constant of (40.4 ± 5.5) nM for TA3, (63.3 ± 24.0) nM for MA1, (71.7 ± 14.6) nM for MA2, (365.9 ± 74.4) nM for MA3, and (21.1 ± 0.5) nM for MA4, respectively. The circular dichroism analysis of the mutant aptamers demonstrated that the GQ structures formed by MA1/MA2, MA3 and MA4 were antiparallel, mixed parallel and parallel, respectively. The affinity of aptamers with various GQ is in the order of parallel structure > antiparallel structure > mixed parallel structure. In addition, to further improve binding ability, the binding conditions of MA4 were optimized as follows: binding time, 60 min; binding temperature, 37 °C; pH of the binding buffer, 7.5; and Na+/Mg2+ concentration in the binding buffer, 100 mM/0.5 mM. The binding examination by fluorescence microscopy showed that MA4 had a stronger binding ability to P. minimum than the original aptamer. Taken together, this study not only obtained an aptamer with higher affinity than the original aptamer, which laid a good foundation for subsequent application, but also may provide a feasible reference method for aptamer optimization.


Assuntos
Aptâmeros de Nucleotídeos , Quadruplex G , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Sondas Moleculares
10.
Environ Sci Pollut Res Int ; 30(4): 10346-10359, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36076134

RESUMO

In recent years, Prorocentrum donghaiense, as a dominant species, has ranked first in terms of cumulative number and area of algal blooms in the East China Sea. In this study, the D1-D2 region of the large ribosomal subunit of P. donghaiense was used as the target gene, and specific primers DH-FP/DH-RP were designed according to the species-specific region of the target gene. An easy, sensitive and visual detection method refered to as polymerase chain reaction-nucleic acid chromatography strip (PCR-NACS) was established for P. donghaiense. The optimized parameters of the PCR amplification system are as follows: primer concentration, 0.15 µM; annealing temperature, 62 °C; and Mg2+ concentration, 1.5 mM. The specificity test showed that PCR-NACS was exlusively specific for the detection of the target algae. The sensitivity test show that the lowest detection limit (LDL) of PCR-NACS was 2.7 × 10-2 ng·µL-1 for genomic DNA and 3.58 × 102 copies·µL-1 for plasmid DNA, respectively. The tests using both genomic DNA and plasmid DNA as templates showed that the sensitivity of PCR-NACS was 10 times higher than that of ordinary PCR. The stability test showed that the interfering algal species did not affect the detection of the target algae by PCR-NACS. In addition, the test with simulated natural samples containing target algae showed that the LDL of PCR-NACS could reach 1.27 × 101 cells·mL-1. In summary, the PCR-NACS established in this study may provide a new method for easy identification of P. donghaiense in natural water samples.


Assuntos
Dinoflagellida , Ácidos Nucleicos , Dinoflagellida/genética , Reação em Cadeia da Polimerase , Proliferação Nociva de Algas , DNA , Cromatografia
11.
Food Chem X ; 14: 100349, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35663597

RESUMO

As an edible coating substrate, the detection of shellac resin has always been an intractable problem. In this paper, an authentication method of shellac resin in shellac-based edible coatings was established. Results showed that the authentication of shellac resin could be skillfully transformed as the identification of 13 targeted metabolites which were monomer compounds of shellac resin. The 13 targeted metabolites were further divided into 6 differential metabolites and 7 common metabolites with the metabonomic method and difference analysis of targeted metabolite contents. Then, four commercial soi-disant shellac-based coating solutions were selected to verify the feasibility of this method, and 7 common metabolites were detected in only one commercial sample, highly consistent with the results of shellac resin. All the above results indicated that the targeted metabolomics approach established in this study could provide a scientific basis for the qualitative authentication of shellac resin in the preservation coating.

12.
Sci Total Environ ; 830: 154771, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35339548

RESUMO

Prorocentrum minimum is a common diarrhetic shellfish toxins-producing marine microalga that may seriously endanger marine resources and cause great economic losses. The development of a novel rapid detection technique is of great importance for the prevention and control of the damage caused by P. minimum. In this study, the aptamer against P. minimum was for the first time generated from an artificially synthesized single-stranded DNA library by systematic evolution of ligand by exponential enrichment (SELEX), using P. minimum and P. minimum-related species, including Prorocentrum donghaiense, Prorocentrum lima and Prorocentrum micans as target and counter-screening species, respectively. The aptamer library was successfully obtained at the end of 18 rounds of SELEX-screening by continuously monitoring the binding ratio of the resultant ssDNA from each round. Three sequences (Apt 1, Apt 2 and Apt 3) with the highest frequency in the aptamer library resulted from high-throughput sequencing were first selected as candidate aptamers. The secondary structure of these sequences was predicted and analyzed. In addition, the specificity and affinity of these candidate aptamers were determined by flow cytometry analysis. The results indicated that these aptamers had high specificity and affinity, with a KD of (224.6 ± 8.8) nM (Apt 1), (286.6 ± 13.9) nM (Apt 2) and (388.5 ± 44.6) nM (Apt 3), respectively. Apt 1 was therefore chosen as the best aptamer against P. minimum. Finally, the fluorescence microscopic examination further confirmed that Apt 1 can well bind to P. minimum. In summary, Apt 1 may be promising for being used as a novel molecular recognition element for P. minimum.


Assuntos
Aptâmeros de Nucleotídeos , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/metabolismo , DNA de Cadeia Simples , Biblioteca Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Técnica de Seleção de Aptâmeros/métodos
13.
J Agric Food Chem ; 69(35): 10281-10291, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34432462

RESUMO

Food wastage represented by the deterioration of perishable food like fruits and vegetables is a serious global problem with tremendous ethical, financial, and environmental costs. The atmosphere (CO2 and O2) has a crucial role in food storage and can regulate physiological food metabolism and microbial growth. Modified atmosphere packaging (MAP) is a promising method used to extend shelf life and preserve the quality of perishable food; yet, its use depends on the specific gas permeability and selectivity of polymer membranes to generate an atmosphere desirable for storage. In this study, we established and validated a new plant leaf-mimetic shellac-based MAP membrane embedded with chitosan porous microspheres loaded with antimicrobial tannic acid (TA-CPM) as gas "switches" for regulating O2 and CO2 permeability and CO2/O2 selectivity. The effects of different amounts of TA-CPM added into the hybrid membranes were examined for litchi preservation at room temperature. Our results showed that this hybrid TA-CPM/shellac packaging membrane could regulate the internal CO2 and O2 concentrations and the CO2/O2 ratio within the packages containing litchis by adjusting the addition amount of TA-CPM. The 0.05% TA-CPM/shellac and 0.10% TA-CPM/shellac packages, especially 0.05% TA-CPM/shellac, generated a more desirable CO2 and O2 atmosphere for litchi preservation compared with controls, which was reflected by the delaying of browning and rotting, maintaining of the natural color of the litchi pericarp, preservation of pulp quality, inhibition of polyphenol oxidase and guaiacol peroxidase activities, and reduction of oxidative cell damage in litchis. The results suggested that 0.05% TA-CPM/shellac and 0.10% TA-CPM/shellac packaging membranes, especially 0.05% TA-CPM/shellac, could generate an ideal atmosphere for litchi storage at room temperature, demonstrating that this permeation-controlled hybrid membrane has great potential in food preservation and other applications requiring a modified atmosphere.


Assuntos
Litchi , Atmosfera , Microbiologia de Alimentos , Embalagem de Alimentos , Conservação de Alimentos , Frutas , Microesferas , Oxigênio , Porosidade
14.
ACS Nano ; 15(5): 8742-8752, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-33970594

RESUMO

About one-third of the world's food is lost and wasted each year, along with excessive carbon emission, disposals, and other environmental issues. The rotting of perishable products like fruits and vegetables accounts for the largest percentage of food waste due to their short shelf life. The storage atmosphere (H2O, O2, CO2) acts as a key role in the preservation process and could regulate plants' physiological metabolism and microbial growth. In this work, a facile and biomimetic strategy is introduced for food preservation at room temperature employing PLLA (poly(l-lactic acid)) or chitosan porous microspheres as gas "switches" or "stomata" in a shellac membrane to regulate O2, CO2, and H2O permeability and CO2/O2 selectivity. Surface coatings on fruits or packaging films prepared through this strategy show exceptional preservation performance on five selected model fruits with different respiratory metabolisms. These hybrid materials could effectively control the gases (O2, CO2, and H2O) permeability and CO2/O2 selectivity by adding different amounts of porous microspheres or depositing small functional molecules, which demonstrate excellent antioxidant, antimicrobial, water-resistant, and reusable properties. This gas permeation control strategy has great potential in food preservation as well as other applications where a controlled atmosphere is required.


Assuntos
Embalagem de Alimentos , Eliminação de Resíduos , Biomimética , Gases , Folhas de Planta
15.
Food Chem ; 354: 129510, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33752113

RESUMO

This study aimed to investigate the combined effects of a coating based on shellac and the active agent tannic acid (TA) on the storability and physiological variations of mangoes stored at room temperature. Results showed that TA-shellac prolonged shelf life and improved overall quality of mangoes to a higher extent compared with controls, which was reflected in the extension of shelf life for approximately 10 days, maintaining of tissue firmness and weight loss, slowing down of respiration rate, improvement of physical properties and chemical qualities, suppression of browning, reduction of lipid peroxidation, preservation of aromatic volatiles, and regulation of the related enzymes activities. Addition of TA to shellac coating also improved the antifungal effect of the formulation. The results suggest that a synergistic effect took place between TA and shellac, which demonstrates the high potential for shelf life extension and quality improvement of mangoes of this formulation.


Assuntos
Embalagem de Alimentos/métodos , Mangifera/metabolismo , Resinas Vegetais/química , Taninos/química , Antioxidantes/química , Antioxidantes/metabolismo , Cor , Filmes Comestíveis , Etilenos/metabolismo , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Malondialdeído/metabolismo , Temperatura , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química
16.
ACS Omega ; 5(35): 22551-22559, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32923814

RESUMO

Bleached shellac, a widely used material in food processing and products, was deeply affected in terms of structures and properties by the bleaching method. In the present study, a marked difference was observed between the damage performances of sodium hypochlorite-bleached shellac (SHBS) and hydrogen peroxide-bleached shellac (HPBS). The main bleaching damage reactions of sodium hypochlorite were the addition of double bonds to generate chlorine and the oxidation of hydroxyl to form aldehydes or ketones. In the case of hydrogen peroxide, degradation of shellac resin was caused by the hydrolysis of ester bonds and the oxidation of hydroxyl groups to form aldehydes and ketones, as well as carboxylic acids with deep oxidation. Based on the structural characterization of shellac resin, the bleaching damages were affected by the bleaching agent via the oxidizable groups, such as the unsaturated double bonds, hydroxyl and aldehyde groups in cyclic terpenes, and fatty acid chains. The differences could be attributed to the action of sodium hypochlorite on the hydroxyl group of aldehyde or ketone. Conversely, hydrogen peroxide bleaching oxidized the hydroxyl group and aldehyde group to carboxylic acid and initiated the hydrolysis reaction of the ester bond of the shellac resin, leading to the degradation of the resin. Thus, understanding the mechanism underlying the bleaching damage could provide a scientific basis for the subsequent targeted regulation of bleaching damage.

17.
J Agric Food Chem ; 68(12): 3779-3785, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32142264

RESUMO

Renewable biobased porous aerogels with excellent biodegradability have versatile applications in oil/water separation, catalysis, and tissue engineering. However, processing of the porous matrix is challenging due to the high energy consumption and low efficiency from the fabrication procedures, such as freeze-drying or critical-drying of the hydrogel, which need to be improved. In the present study, natural amphiphilic oligomer shellac secreted by the lac Kerriar Lacca insect was employed to fabricate the porous template, which could self-assemble into a continuous rigid network with a hydrophobic core. Because of the hydrophobic core, the hydrated shellac network could be directly dried without collapse by the ambient air. The air-drying shellac aerogel presented a great mechanical property. The silane-coating treatment converted this shellac aerogel into a hydrophobic material that absorbed various organic solvents and oils. Also, this silane-coated shellac aerogel also could remove organic solvent or oil from the bottom or surface of the water. Notably, the saturable aerogel rapidly degraded in pH 14 and released the solvent absorbed by this matrix. This porous and hydrophobic matrix also could be applied as a filter that could connect with a vacuum pump to assemble a device for continuous collecting of oil from water. It also has great potential to be employed as a high-efficiency strategy to treat large scale oil spill issues. A new porous template composed of natural resin secreted by the insect was fabricated, and the whole fabrication process was green, low-cost, and energy saving. The surface of this template could be modified further to effectuate other processes, such as catalysis, heavy metal absorption, and tissue proliferation.


Assuntos
Géis/química , Óleos/isolamento & purificação , Silanos/química , Poluentes Químicos da Água/isolamento & purificação , Água/análise , Adsorção , Animais , Liofilização/métodos , Interações Hidrofóbicas e Hidrofílicas , Insetos/química , Poluição por Petróleo/análise , Porosidade , Solventes/isolamento & purificação , Purificação da Água/métodos
18.
Carbohydr Polym ; 199: 186-192, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30143119

RESUMO

The smart polyphenol material could be designed to form two competitive interactions related to same one polyphenol molecule with different objects that could easily adhere to one surface through the weak interaction, and also could be entirely removed from the same surface by the strong interaction. In this study, the multi-scale pectin beads were fabricated by crosslinking with ions that could be acted as polyphenol loading agent through electrostatic force between the ions loading on the surface of pectin beads and polyphenol. The two effects on the size and appearance of pectin beads were detected. Because of the hydrogen bond between polyphenols loading on the beads and the surface of target, fluorescence-functionalized beads could easily adhere on target surfaces. Meanwhile, attributing to stronger electrostatic force between surface ions on beads and polyphenol, the thin membrane made of the beads can be entirely removed from the target surface to avoid the pollution of fluorescence probes.

19.
J Agric Food Chem ; 66(26): 6799-6805, 2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29878772

RESUMO

Sodium shellac constituted of a "surfactant" monomer, which is sensitive to shear stress, exhibits shear-thickening behavior at a low concentration (5 wt %), and reacts with H+ to retain transient high viscosity under shear, is introduced in this study. The steady shear flow test proved that, under a high shear rate, sodium shellac suspension could change from Newtonian fluid to continuous shear-thickening non-Newtonian fluid. The dynamic oscillation test suggested that the sodium shellac solution at low concentrations (0.1 and 1 wt %) under a low shear rate behaved as the viscous fluid ( G″ > G'), and the solution at high concentrations (5, 10, and 15 wt %) behaved as the elastic fluid ( G″ < G'). Moreover, a high shear rate caused a cross-linking point between the G″ and G' curve. At a low concentration, it could be the sol-gel point. At a high concentration, it could be the gel-sol point. All of these transforming points were related to the interaction between the sodium clusters. This interaction should be the hydrophobic association between the particles. To prove the assumption, hydrophilic polymer poly(ethylene oxide) (PEO) was employed as the disrupting factor to the hydrophobic association. As expected, the shear-thickening behavior vanished after mixing with PEO, which verified our assumption. On the other hand, the high viscosity of the suspension under shear could be retained by reaction with H+ to solidify the transient hydroclusters under shear. Meanwhile, sodium shellac had great potential as the functional shear thickener, which could modify the rheological property of the polymer with carboxyl groups, e.g., pectin, alginate, or poly(acrylic acid). Thus, this natural and green thicker has great potential in food, medical gel, green adhesive, or cosmetic products.


Assuntos
Aditivos Alimentares/química , Resinas Vegetais/química , Alginatos/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Interações Hidrofóbicas e Hidrofílicas , Reologia , Temperatura , Viscosidade
20.
PLoS One ; 13(5): e0197343, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29763430

RESUMO

BACKGROUND: Insect wax is a famous biological resource for the role in economic production in China. Insect wax is a good source of policosanol, which may is a candidate supplement in foodstuff and pharmaceuticals that has important physiological activities. Therefore, this work aims to investigate a high-yield and rapid method for policosanol fabrication from insect wax. RESULTS: The conditions for policosanol fabrication were optimized as follows: an oil bath temperature of 112.7°C and reductant dosage of 0.97 g (used for the reduction of 10.00 g of insect wax). The yield of policosanol reached 83.20%, which was 4 times greater than that of existing methods, such as saponification. The total content of policosanol obtained under the optimal conditions reached 87%. In other words, a high yield of policosanol was obtained from insect wax (723.84 mg/g), that was 55 times higher than that generated from beeswax-brown via saponification. The concentrations of metal residues in policosanol were within the limits of the European Union regulations and EFSA stipulation. The LD50 values for oral doses of insect wax and policosanol were both > 5 g/kg. CONCLUSION: Policosanol was fabricated via solvent-free reduction from insect wax using LiAlH4 at a high yield. The fabrication conditions were optimized. Policosanol and insect wax showed high security, which made them potential candidates as supplements in foods, pharmaceuticals and cosmetics. The rapid and high-yield method has great potential for commercial manufacturing of policosanol.


Assuntos
Álcoois Graxos/isolamento & purificação , Insetos , Ceras , Administração Oral , Compostos de Alumínio/química , Animais , Álcoois Graxos/química , Álcoois Graxos/toxicidade , Feminino , Compostos de Lítio/química , Ratos Sprague-Dawley , Temperatura
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