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1.
Food Chem ; 367: 130635, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34352690

RESUMO

In this study, tailored-made citrus pectin-derived compounds were produced through controlled enzymatic and/or chemical modifications of commercial citrus pectin with different degrees of methylesterification (DM) and similar average molecular weight (MW). In the first treatment, degradation of the citrus pectin (CP) materials by endo-polygalacturonase (EPG) yielded pectins with average Mw's (between 2 and 60 kDa). Separation and identification of the oligosaccharide fraction present in these samples, revealed the presence of non-methylesterified galacturonic acid oligomers with degree of polymerization (DP) 1-5. In the second treatment, exploiting the combined effect of EPG and pectin lyase, compounds with MW between 2 and 21 kDa, containing methylesterified and non-methylesterified polygalacturonans (DP 1-6), were generated. Finally, CP was sequentially modified by chemical saponification and the action of EPG. A sample of DM 11% and MW 2.7 kDa, containing POS (DP 1-5), was produced. Diverse pectin-derived compounds were successfully generated for further studies exploring their functionality.


Assuntos
Citrus , Pectinas , Peso Molecular , Oligossacarídeos , Poligalacturonase/genética
2.
Food Chem ; 367: 130726, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34352698

RESUMO

The impact of different complexes on the properties of ß-carotene-loaded emulsions was investigated by measuring the droplet size, encapsulation efficiency, droplet morphology, and physical stability. The photo and thermal stability of ß-carotene and its bioaccessibility during digestion were also analyzed. Comparing to the emulsions stabilized by other complexes, the emulsion stabilized by the high methoxyl pectin-rhamnolipid-pea protein isolate-curcumin (HMP-Rha-PPI-Cur) complex had the smallest droplet size (17.53 ± 0.15 µm) and the maximum encapsulation efficiency for curcumin (90.33 ± 0.03 %) and ß-carotene (92.16 ± 0.01 %). The emulsion stabilized by the HMP-Rha-PPI-Cur complex exhibited better physical stability against creaming. The retention rate of ß-carotene in the HMP-Rha-PPI-Cur complex-stabilized emulsion was 17.75 ± 0.02 and 33.64 ± 0.02 % after UV irradiation and thermal treatment. The HMP-Rha-PPI-Cur complex-stabilized emulsion also had a higher level of free fatty acid released (43.67 %) and higher bioaccessibility of ß-carotene (32.35 ± 0.02 %).


Assuntos
Curcumina , Proteínas de Ervilha , Carotenoides , Emulsões , Tamanho da Partícula , Pectinas , Tensoativos , beta Caroteno
3.
An Acad Bras Cienc ; 93(4): e20200721, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495203

RESUMO

The aim of the study was to evaluate the effect of the jambolan (Syzigium cumini L.) peel and leaves extract added in pectin based edible coating onto color changes, mass loss and ß-carotene retention of minimally processed papaya during storage at 5 ±2 °C for 9 days. Leaves and peels were crushed in water in solid:liquid ratio, 1:1.5 and 1:2.0 and filtrered to obtain vegetable extracts. After, aqueous solutions were prepared adding 2% of pectin and 5% of extract. The mass loss increasing in all treatments evaluated in this work, being that in the final of 9 days of storage, control and P2 (peel 2%) treatment presented the highest loss, 6.23 and 10.12% respectively. The L1.5 (leaf 1.5%) treatment was the one presented the lowest percentage of mass loss (3.8%). The values of () of the control samples reduced significantly during the storage period, reaching 21% of reduction after 9 days. Coating with vegetable extract from jambolan peel and leaf reduced the loss of ß-carotene in minimally processed papaya during the storage, being that the treatment P1.5 provided the highest retention value of the compound. The results demonstrated that the studied coating set with extracts (peel and leaves) of jambolan, was efficient to preserve the color, the mass loss and the ß-carotene content of the minimally processed papaya.


Assuntos
Carica , Filmes Comestíveis , Pectinas , Extratos Vegetais , Verduras , beta Caroteno/análise
4.
Enzyme Microb Technol ; 150: 109894, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34489047

RESUMO

Aspergillus oryzae is a safe microorganism that is commonly used in food production. We constructed a self-cloning vector capable of high expression in A. oryzae. Using the vector, three putative pectin methylesterase (PME) genes belonging to Carbohydrate Esterase family 8 derived from A. oryzae were expressed, and several characteristics of the gene products were examined. The effects of temperature and pH on the three enzymes (AoPME1, 2, and 3) were similar, with optimal reaction temperatures of 50 - 60 °C and optimal reaction pH range of 5 - 6. The specific activities of AoPME1, 2, and 3 for apple pectin were significantly different (34, 7,601, and 2 U/mg, respectively). When the substrate specificity was examined, AoPME1 showed high activity towards pectin derived from soybean and pea. Although AoPME2 showed little activity towards these pectins, it showed very high activity towards apple- and citrus-derived pectins. AoPME3 showed low specific activity towards all substrates tested. Sugar composition analysis revealed that apple- and citrus-derived pectins were rich in homogalacturonan, while soybean- and pea-derived pectins were rich in xylogalacturonan. When pea pectin was treated with endo-polygalacturonase or endo-xylogalacturonase in the presence of each PME, specific synergistic actions were observed (endo-polygalacturonase with AoPME1 or AoPME2 and endo-xylogalacturonase with AoPME1 or AoPME3). Thus, AoPME1 and AoPME3 hydrolyzed the methoxy group in xylogalacturonan. This is the first report of this activity in microbial enzymes. Our findings on the substrate specificity of PMEs should lead to the determination of the distribution of methoxy groups in pectin and the development of new applications in the field of food manufacturing.


Assuntos
Aspergillus oryzae , Aspergillus oryzae/genética , Hidrolases de Éster Carboxílico/genética , Vetores Genéticos , Ácidos Hexurônicos , Pectinas
5.
Soft Matter ; 17(37): 8517-8522, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34494060

RESUMO

Electrostatic complexation of negatively charged polysaccharides with ß-lactoglobulin (ß-lg) has been shown to bolster the protein films at oil/water interfaces thereby improving emulsion stability. However, recent sub-phase exchange experiments demonstrated that highly charged polysaccharides such as low methyl-esterified pectin are complementary only if sequentially introduced to a pre-formed interfacial ß-lg film. In this study, results of transient interfacial shear rheology show that, by using high-methylesterified pectins instead, complexes can be formed in pre-mixed solutions with ß-lg at pH 4 that can lead to reinforced protein films at dodecane/water interfaces. Using this one-shot adsorption of such complexes, pectins as well as short chain polysaccharides like homogalacturonan nearly doubled the steady state shear elastic moduli as compared to that of a pure ß-lg film. The lag times of film formation were established to be primarily decided by the charge density and pattern on the polysaccharide. Based on the results from mixed solutions of ß-lg monomers, it is proposed that the polysaccharide at pH 4 strengthens the resulting interfacial layer by concatenating adsorbed ß-lg molecules thereby establishing cross-links in the aqueous phase.


Assuntos
Lactoglobulinas , Pectinas , Adsorção , Emulsões , Concentração de Íons de Hidrogênio , Eletricidade Estática
6.
Pestic Biochem Physiol ; 178: 104919, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34446195

RESUMO

BACKGROUND: Paraquat poisoning leads to lung injury and pulmonary fibrosis. The effect of paraquat encapsulation by previously described Pectin/Chitosan/Tripolyphosphate nanoparticles on its pulmonary toxicity was investigated in present study in a rat model of poison inhalation. MATERIAL AND METHOD: The rats inhaled nebulized different formulation of paraquat (n = 5) for 30 min in various experimental groups. Lung injury and fibrosis scores, Lung tissue enzymatic activities, apoptosis markers were determined compared among groups. RESULTS: Encapsulation of paraquat significantly rescued both lung injury and fibrosis scores. Lung MDA level was reduced by encapsulation. Paraquat poisoning led to lung tissue apoptosis as was evidenced by higher Caspase-3 and Bax/Bcl2 expressions in rats subjected to paraquat inhalation instead of normal saline or free nanoparticles. Again, nanoencapsulation reduced these apoptosis markers significantly. Alpha-SMA expression was also reduced by encapsulation. Nanoparticles per se have no or little toxicity as was evidenced by inflammatory and apoptotic markers and histological scores. CONCLUSION: In a rat model of inhalation toxicity of paraquat, loading of this herbicide on PEC/CS/TPP nanoparticles reduced acute lung injury and fibrosis. The encapsulation also led to lower apoptosis, oxidative stress and alpha-SMA expression in the lung tissue.


Assuntos
Quitosana , Paraquat , Animais , Apoptose , Fibrose , Pulmão/patologia , Paraquat/toxicidade , Pectinas , Polifosfatos , Ratos
7.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 33(7): 871-875, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34412760

RESUMO

OBJECTIVE: To evaluate the intestinal function in rats with exertional heat stroke (EHS) and explore the protective role of Ruifuping pectin (RFP) against heat related intestinal mucosal injury. METHODS: One hundred and twenty healthy special pathogen free (SPF) male Sprague-Dawley (SD) rats were randomly divided into normothermic control group, EHS model group, hyperthermic plus drinking water group (H2O+EHS group) and hyperthermic plus pectin group (RFP+EHS group) with 30 rats in each group. The rats in the H2O+EHS group and RFP+EHS group were given water 20 mL/kg or RFP 20 mL/kg orally for 5 days during adaptive training period. After 1 week, the temperature control range was adjusted to (37±1) centigrade using the temperature control treadmill, and the rat model of EHS was reproduced by one-time high temperature exhaustive exercise. No rehydration intervention was given during the training adaptation period in the EHS model group. The rats in the normothermic control group were maintained to room temperature (25±2) centigrade and humidity (55±5)% without other treatment. Behavior tests including withdraw response, righting, and muscle strength were performed immediately after onset of EHS. Blood of inferior vena cava was collected, and the serum inflammatory cytokines [tumor necrosis factor-α (TNF-α) and interleukins (IL-6, IL-1ß, IL-10)] and activity of diamine oxidase (DAO) were detected by enzyme linked immunosorbent assay (ELISA). The intestinal mucosa was collected, after hematoxylin-eosin (HE) staining, and Chiu score was performed to assess EHS induced pathological changes under light microscope. RESULTS: The rats in the EHS model group had behavioral, inflammatory and pathological changes, such as delayed withdraw response and righting, decreased forelimb pulling, increased inflammatory index, and obvious intestinal mucosal injury, which indicated that the reproduction of the EHS model was successful. There was no significant difference in above parameters between the H2O+EHS group and the EHS model group except that the inflammatory index in the RFP+EHS group was improved. Compared with the EHS model group, the withdraw reflex to pain and righting after RFP pretreatment in the RFP+EHS group were significantly improved (righting score: 1.4±0.2 vs. 0.3±0.2, withdraw reflex to pain score: 1.0±0.1 vs. 0.2±0.1, both P < 0.05), the muscle strength was significantly increased (N: 13.0±0.5 vs. 8.2±0.6, P < 0.01). The levels of pro-inflammatory factors in the RFP+EHS group were significantly lower than those in the EHS model group [TNF-α (ng/L): 67.5±9.2 vs. 194.3±13.7, IL-6 (ng/L): 360.0±54.1 vs. 981.2±84.4, IL-1ß (ng/L): 33.7±9.0 vs. 88.7±6.1, all P < 0.01], while the level of anti-inflammatory factor IL-10 was higher than that in the EHS model group (ng/L: 208.7±10.5 vs. 103.7±7.0, P < 0.01). The degree of intestinal mucosal injury in the RFP+EHS group was less severe than that in the EHS model group, and the Chiu score and DAO were significantly lower than those in the EHS model group [Chiu score: 1.5±0.2 vs. 3.8±0.0, DAO (U/L): 83.7±6.7 vs. 128.7±10.5, both P < 0.05]. CONCLUSIONS: High temperature training can damage the intestinal barrier function, and induce endotoxemia and systemic inflammatory response syndrome (SIRS) in rats. Oral prophylactic RFP can protect the intestinal barrier function, alleviate SIRS, and promote the recovery of basic nerve reflex and muscle strength after the occurrence of EHS in rats.


Assuntos
Golpe de Calor , Pectinas , Animais , Mucosa Intestinal , Masculino , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa
8.
J Food Sci ; 86(10): 4539-4553, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34431096

RESUMO

Persimmon is among the fruits with a significant postharvest loss over the last few years. Thus, it is important to investigate new technical feasibilities to obtain products with higher added value from this fruit. In this study persimmon puree films (Diospyros kaki L.) incorporated with glycerol and pectin by casting technique were formulated using a Plackett-Burman design and characterized. The puree showed high carbohydrate content (175.70 g/kg). In descending order, fructose, glucose, and maltohexaose were the sugars found in persimmon. All the independent variables studied-puree concentration, pectin, glycerol, and temperature-statistically influenced the tensile strength (0.75-1.30 MPa), elongation at break (17.69-26.02%), and Young's modulus (3.34-10.94 MPa) of the films. Water solubility ranged from 68.80% to 80.86%, which were very similar to other films based on puree fruit in the literature. Samples presented high vapor permeability (5.77-6.63 × 10-6 g/h/m/Pa) when compared to biodegradable films. Scanning electron microscopy showed smooth surfaces and good plasticizer dispersion. The colorimetric coordinates indicated the films are reddish and yellowish, giving them an orange-ish visual aspect. The films exhibited antimicrobial activity, especially against Escherichia coli and Staphylococcus aureus. These results indicate that the developed films might be a good candidate for antimicrobial food packaging improving food quality and safety. PRACTICAL APPLICATION: The production of fruit-film packaging with functional and biodegradable characteristics might reduce postharvest loss of fruit and have the potential to develop active food packaging. In this sense, this study is in line with precepts of the circular economy, once it takes advantage of exceeded resources that would be discarded by generating biodegradable films which can be used as edible packaging. Furthermore, given the antimicrobial potential of the films developed, they might be applied as active packaging to improve food safety and extend shelf life.


Assuntos
Diospyros , Embalagem de Alimentos , Glicerol , Pectinas , Antibacterianos/farmacologia , Diospyros/química , Embalagem de Alimentos/métodos , Frutas/química , Glicerol/química , Pectinas/química , Permeabilidade , Resistência à Tração
9.
Life Sci ; 284: 119910, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34453939

RESUMO

AIMS: Quercetin has been investigated as an agent to treat rheumatoid arthritis. At high doses it improves inflammation and the antioxidant status of arthritic rats, but it also exerts mitochondriotoxic and pro-oxidant activities. Beneficial effects of quercetin have not been found at low doses because of its chemical instability and low bioavailability. In the hope of overcoming these problems this study investigated the effects of long-term administration of quercetin-loaded pectin/casein microparticles on the oxidative status of liver and brain of rats with adjuvant-induced arthritis. MAIN METHODS: Particle morphology was viewed with transmission electron microscopy and the encapsulation efficiency was measured indirectly by X-ray diffraction. Quercetin microcapsules (10 mg/Kg) were orally administered to rats during 60 days. Inflammation indicators and oxidative stress markers were measured in addition to the respiratory activity and ROS production in isolated mitochondria. KEY FINDINGS: Quercetin was efficiently encapsulated inside the polymeric matrix, forming a solid amorphous solution. The administration of quercetin microparticles to arthritic rats almost normalized protein carbonylation, lipid peroxidation, the levels of reactive oxygen species as well as the reduced glutathione content in both liver and brain. The paw edema in arthritic rats was not responsive, but the plasmatic activity of ALT and the mitochondrial respiration were not affected by quercetin, indicating absence of mitochondriotoxic or hepatotoxic actions. SIGNIFICANCE: Quercetin-loaded pectin/casein microcapsules orally administered at a low dose improve oxidative stress of arthritic rats without a strong anti-inflammatory activity. This supports the long-term use of quercetin as an antioxidant agent to treat rheumatoid arthritis.


Assuntos
Artrite Experimental/patologia , Caseínas/química , Microesferas , Estresse Oxidativo , Pectinas/química , Quercetina/farmacologia , Alanina Transaminase/sangue , Animais , Antioxidantes/farmacologia , Artrite Experimental/sangue , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Varredura Diferencial de Calorimetria , Respiração Celular/efeitos dos fármacos , Edema/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
10.
Science ; 373(6556): 774-779, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34385392

RESUMO

The oomycete Phytophthora infestans is a damaging crop pathogen and a model organism to study plant-pathogen interactions. We report the discovery of a family of copper-dependent lytic polysaccharide monooxygenases (LPMOs) in plant pathogenic oomycetes and its role in plant infection by P. infestans We show that LPMO-encoding genes are up-regulated early during infection and that the secreted enzymes oxidatively cleave the backbone of pectin, a charged polysaccharide in the plant cell wall. The crystal structure of the most abundant of these LPMOs sheds light on its ability to recognize and degrade pectin, and silencing the encoding gene in P. infestans inhibits infection of potato, indicating a role in host penetration. The identification of LPMOs as virulence factors in pathogenic oomycetes opens up opportunities in crop protection and food security.


Assuntos
Lycopersicon esculentum/parasitologia , Oxigenases de Função Mista/metabolismo , Pectinas/metabolismo , Phytophthora infestans/enzimologia , Doenças das Plantas/parasitologia , Solanum tuberosum/parasitologia , Cobre , Oxigenases de Função Mista/química , Oxigenases de Função Mista/genética , Modelos Moleculares , Oxirredução , Phytophthora infestans/genética , Phytophthora infestans/patogenicidade , Folhas de Planta/parasitologia , Polissacarídeos/metabolismo , Conformação Proteica , Domínios Proteicos , Fatores de Virulência/química , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
11.
J Agric Food Chem ; 69(32): 9376-9382, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34351140

RESUMO

Past investigations have shown high browning potential during the caramelization of sugar acids in comparison to reducing sugars. However, no approaches to elucidate the chemical mechanisms have been made. Therefore, this study aims to clarify the reasons for the high browning potential by measuring the mutarotation velocity and the elimination of CO2 during the heat treatment of uronic acids. Performed polarimetric experiments show that the mutarotation velocity of d-galacturonic acid exceeds that of d-galactose by a factor of nearly 4.5. However, the ring opening velocity is not the only parameter that differs between the two carbohydrate structures. Measurements of the release of CO2 of heated d-galacturonic acid at 60 °C show a steady increase, and after 48 h, 6% of degraded d-galacturonic acid has eliminated CO2. CO2 release was also found during the heating of pectin, indicating a decarboxylation reaction during thermal degradation. One of the degradation reactions postulated for the release of CO2 leads to α-ketoglutaraldehyde, which is responsible for the formation of several chromophoric substances.


Assuntos
Polímeros , Ácidos Urônicos , Ácidos Hexurônicos , Pectinas
12.
Colloids Surf B Biointerfaces ; 206: 111936, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34214839

RESUMO

In this study, the effect of high-pressure steam sterilization (121 °C for 15 min) on whey protein hydrolysate-pectin solutions and emulsions was studied. The interaction and emulsification characteristics of pectin and whey protein concentrate (WPC) were evaluated from the solution system to the emulsion system. Enzymatic hydrolysis of WPC (WPH, 2 % and 8 % degree of hydrolysis) increased the covalent binding with pectin, which reduced the heat-induced aggregation of protein and improved emulsification. The thermodynamic incompatibility between WPC and pectin was not conducive to the covalent bonding under high temperature sterilization and produced serious aggregates, which also made a rapid increase in particle size (up to ∼3 µm), compared to WPH-pectin emulsion (∼ 400 nm). In addition, if emulsion was stirred during the sterilization, the creaming and protein aggregation could be avoided. By comparing low methoxy pectin (LMP) and high methoxy pectin (HMP), it was found that the whey protein-HMP complex had better emulsification stability, and the steric stabilization played a more important role in emulsion stability than the electrostatic repulsion. The changes of whey protein and pectin at the oil-water interface of the emulsion during the sterilization process may provide a reference for the sterilized bioactive ingredient delivery system.


Assuntos
Pectinas , Hidrolisados de Proteína , Emulsões , Temperatura Alta , Esterilização , Temperatura , Soro do Leite , Proteínas do Soro do Leite
13.
Int J Biol Macromol ; 185: 441-450, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34197849

RESUMO

Biomaterials for effective hemorrhage control are urgently needed in clinics as uncontrolled bleeding is associated with high mortality. Herein, we developed an injectable and in situ photo-crosslinkable hybrid hemostatic hydrogel by combining pectin methacrylate (PECMA) and gelatin methacryloyl (GelMA). This modular material system combines ionic- and photo-crosslinking chemistries to design interpenetrating networks (IPN) exhibiting tunable rheology, highly porous structure, and controllable swelling and mechanical properties. By simply changing the calcium (0-15 mM) and polymer (1.5-7%) content used for the sequential crosslinking of hydrogels via calcium gelation and UV-photopolymerization, it was possible to precisely modulate the injectability, degradation, and swelling ratio. Moreover, it is demonstrated that PECMA/GelMA hydrogels present good cytocompatibility and uniquely synergize the hemostatic properties of calcium ions on PECMA, the amine residues on GelMA, and the highly porous network toward rapid blood absorption and fast coagulation effect. An in vitro porcine skin bleeding model confirmed that the hydrogel could be directly injected into the wound and rapidly photo-crosslinked, circumventing the bleeding and decreasing the coagulation time by 39%. Importantly, the crosslinked hydrogel could be easily removed to prevent secondary wound injury. Overall, this injectable hybrid PECMA/GelMA hydrogel stands as a promising hemostatic material.


Assuntos
Cálcio/metabolismo , Gelatina/química , Metacrilatos/química , Pectinas/química , Cicatrização/efeitos dos fármacos , Animais , Linhagem Celular , Hemostasia , Injeções , Camundongos , Fenômenos Físicos , Porosidade , Suínos
14.
Int J Biol Macromol ; 185: 959-965, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34229017

RESUMO

Raspberry pomace extracts (RPE) with different concentrations (0.5 g/L, 1.5 g/L and 3 g/L) were incorporated into pectin/sodium alginate/xanthan gum composite film (PAX) to prepare colorimetric raspberry films (PAXR5, PAXR15 and PAXR30). Fourier Transform Infrared and Scanning Electron Microscopy analysis showed RPE had good compatibility with PAX. Compared to PAX, the raspberry films had lower water vapor permeability and water swelling ratio, higher tensile strength, opacity and antioxidant capacity. The films presented a smoother surface and denser structure than PAX. Furthermore, PAXR15 had an excellent discoloration at pH 1-13, especially at pH 5-10, the color changes of PAXR15 from pink-red-brown-blue-dark green distinguished by the naked eyes. Therefore, it has the potential to become a pH-sensitive film used in monitoring protein-rich food freshness.


Assuntos
Alginatos/química , Pectinas/química , Polissacarídeos Bacterianos/química , Rubus/química , Embalagem de Alimentos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Resistência à Tração
15.
Colloids Surf B Biointerfaces ; 207: 111999, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34325297

RESUMO

Here we report on the robust synthesis of zinc sulfide nanoparticles (ZnSNP) using a simple one-pot reaction. The prepared ZnSNP was characterized and confirmed to be a petal-shaped nanoparticle. The ZnSNP was added to fabricate the pectin/agar-based functional composite film. The integration of ZnSNP has greatly improved the physical properties of the film, such as mechanical and UV protection properties, without significantly changing the transparency of the film. The addition of the nanofillers did not affect the film's hydrophobicity, water vapor barrier, and thermal properties. Moreover, the composite film showed intense antibacterial activity against foodborne pathogenic bacteria, E. coli and L. monocytogenes. The functional bio-nanocomposite films based on pectin/agar have high potential in active packaging applications.


Assuntos
Listeria monocytogenes , Nanocompostos , Ágar , Antibacterianos/farmacologia , Escherichia coli , Embalagem de Alimentos , Pectinas , Sulfetos , Compostos de Zinco
16.
Food Chem ; 365: 130585, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34325351

RESUMO

Citrus is one of the main fruits processed worldwide, producing a lot of industrial by-products. As the main part of citrus "residue", citrus peels have a wide application prospect. They could not only be directly used to produce various food products, but also be used as promising biofuels to produce ethanol and methane. Additionally, functional components (flavonoids, limonoids, alkaloids, essential oils and pectin) extracted from citrus peels have been related to the improvement of human health against active oxygen, inflammatory, cancer and metabolic disorders. Therefore, it is clear that the citrus peels have great potential to be developed into useful functional foods, medicines and biofuels. This review systematically summarizes the recent advances in current uses, processing, bioactive components and biological properties of citrus peels. A better understanding of citrus peels may provide reference for making full use of it.


Assuntos
Citrus , Óleos Voláteis , Flavonoides , Frutas , Humanos , Pectinas
17.
J Agric Food Chem ; 69(30): 8403-8414, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34313419

RESUMO

We characterized the structure of prepared citrus pectin oligosaccharides (POS) and investigated the immunometabolism-modulating effects of POS and their microbial metabolites on human macrophages. Both POS and metabolites activated immune responses and exhibited anti-inflammatory properties in the presence of lipopolysaccharide (LPS) via regulating expressions of inflammatory cytokines and nuclear factor-kappa B. Cholesterol efflux was also facilitated via increased gene expressions of the liver X receptor-α-adenosine triphosphate-binding cassette transporter (ABC) A1/ABCG1 pathway and suppressed cholesterol synthesis via suppressing expressions of 3-hydroxy-3-methylglutaryl-coenzyme A reductase. Microbial degradation prevented POS from attenuating palmitoyl-3-cysteine-serine-lysine-4-induced inflammation and promoting M2 polarization, but it is capable of inhibiting cholesterol uptake-related genes CD36 and SR-A. These findings indicate that immunometabolism-modulating effects of POS are not solely microbiota-dependent effects. Both POS and their microbial metabolites are potential immunometabolism modulators via different mechanisms.


Assuntos
Colesterol , Macrófagos , Humanos , Oligossacarídeos/farmacologia , Pectinas
18.
Acta Biomater ; 131: 149-161, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34171460

RESUMO

We report a new injectable and biodegradable self-healing hydrogel that shows enhanced anticancer drug release property. The hydrogel was prepared based on biodegradable pectin aldehyde (pectin-CHO) and acylhydrazide functionalized polymer poly(N-isopropylacrylamide-stat-acylhydrazide) P(NIPAM-stat-AH). Due to the dynamic nature of acylhydrazone bonds, the hydrogel exhibits self-healing behavior and its mechanical properties can be regulated by the weight ratio of P(NIPAM-stat-AH) to pectin-CHO. The in vitro and in vivo experiments show the hydrogel has not only good biocompatibility and biodegradability, but also decreases the toxicity of the drugs to living body and exhibits controlled drug release behavior as synergetic anti-tumor drug delivery carriers. The results demonstrate that the pectin-based self-healing hydrogels are injectable, biodegradable, and self-healable that is promising for localized anti-tumor therapy. STATEMENT OF SIGNIFICANCE: Injectable hydrogels with self-healing property and biodegradability are excellent candidates as drug loading and release carrier for biomedical applications. However the pectin as a biobased material is always neglected in self-healing hydrogel preparation. In this study, we fabricated biodegradable self-healing hydrogels from aldehyde group bearing pectin (pectin-CHO) and thermo-responsive copolymer of P(NIPAM-stat-AH). The hydrogel showed sustained drug release behavior, good biocompatibility and biodegradability both in vitro and in vivo. The in vivo experiment shows that the hydrogel with coloaded DOX and CA4 has synergetic therapy to CT26 tumors and this kind of biodegradable hydrogel has great potential application in antitumor therapy.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Liberação Controlada de Fármacos , Humanos , Hidrogéis , Pectinas
19.
Molecules ; 26(9)2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-34062995

RESUMO

A single ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) that causes inflammation of the colonic mucosa at the distal colon and rectum. The mainstay therapy involves anti-inflammatory immunosuppression based on the disease location and severity. The disadvantages of using systemic corticosteroids for UC treatment is the amplified risk of malignancies and infections. Therefore, topical treatments are safer as they have fewer systemic side effects due to less systemic exposure. In this context, pH sensitive and enzymatically triggered hydrogel of pectin (PC) and polyacrylamide (PAM) has been developed to facilitate colon-targeted delivery of budesonide (BUD) for the treatment of UC. The hydrogels were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), swelling ratio, and drug release. FT-IR spectroscopy confirmed the grafting as well loading of BUD in hydrogel. XRD showed the amorphous nature of hydrogel and increment in crystallinity after drug loading. On the other hand, SEM showed that the hydrogels exhibited a highly porous morphology, which is suitable for drug loading and also demonstrated a pH-responsive swelling behaviour, with decreased swelling in acidic media. The in-vitro release of BUD from the hydrogel exhibited a sustained release behaviour with non-ficken diffusion mechanism. The model that fitted best for BUD released was the Higuchi kinetic model. It was concluded that enzyme/pH dual-sensitive hydrogels are an effective colon-targeted delivery system for UC.


Assuntos
Resinas Acrílicas/química , Budesonida/farmacologia , Liberação Controlada de Fármacos , Hidrogéis/química , Pectinas/química , Varredura Diferencial de Calorimetria , Preparações de Ação Retardada , Hidrogéis/síntese química , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
20.
Molecules ; 26(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068822

RESUMO

The contribution of rheological properties and viscoelasticity of the interfacial adsorbed layer to the emulsification mechanism of enzymatic modified sugar beet pectin (SBP) was studied. The component content of each enzymatic modified pectin was lower than that of untreated SBP. Protein and ferulic acid decreased from 5.52% and 1.08% to 0.54% and 0.13%, respectively, resulting in a decrease in thermal stability, apparent viscosity, and molecular weight (Mw). The dynamic interfacial rheological properties showed that the interfacial pressure and modulus (E) decreased significantly with the decrease of functional groups (especially proteins), which also led to the bimodal distribution of particle size. These results indicated that the superior emulsification property of SBP is mainly determined by proteins, followed by ferulic acid, and the existence of other functional groups also promotes the emulsification property of SBP.


Assuntos
Beta vulgaris/química , Emulsões/química , Enzimas/metabolismo , Pectinas/metabolismo , Reologia , Adsorção , Difusão , Elasticidade , Cinética , Peso Molecular , Óleos/química , Tamanho da Partícula , Pressão , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termogravimetria , Fatores de Tempo , Viscosidade , Água/química
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