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1.
Curr Microbiol ; 81(6): 142, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625396

RESUMO

The present work aims to quantitatively and qualitatively monitor the production of lipopeptide mixtures by Bacillus methylotrophicus DCS1 strain in Landy medium and to investigate the antifungal activities of DCS1 strain and its produced lipopeptides. The in vitro activities were tested by the direct confrontation and agar well diffusion methods, while the in vivo study was carried out in order to test the efficiency of DCS1 bacterial suspension in the control of Fusarium wilt in tomato plants. Identification of lipopeptides by mass spectrometry (LC/MSD-TOF) showed that lipopeptide isoforms produced during the first 24 h and 48 h of fermentation are identical, belonging to bacillomycin D and fengycins A and B homologues with a difference in the yield of production. After 72 h of fermentation corresponding to the end of incubation period, B. methylotrophicus DCS1 is able to produce a mixture of surfactin, pumilacidin, iturin A/mycosubtilin, iturin C1, bacillomycin D and fengycins A and B isoforms. The results of in vitro antifungal experiments suggest that B. methylotrophicus DCS1 has a significant potential as a biocontrol agent, owing to lipopeptides produced, endowed with antifungal activity against several phytopathogenic fungi. The curative treatment of tomato plants with DCS1 bacterial suspension was more effective in the protection against Fusarium oxysporum f. sp. radicis-lycopersici (FORL) than the preventive treatment by comparing the average number of leaves remaining healthy after 30 days of each treatment and the appearance of tomato plants roots. The results indicate that B. methylotrophicus DCS1 exhibit a significant suppression of Fusarium wilt symptoms in tomato plants comparable to that of commercial fungicides and could be an alternative to chemically synthesized pesticides.


Assuntos
Bacillus , Fusarium , Solanum lycopersicum , Antifúngicos/farmacologia , Lipopeptídeos/farmacologia , Isoformas de Proteínas
2.
Food Chem ; 366: 130530, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34303204

RESUMO

In this study, the effects of different temperatures, incubation times and types of reducing sugars, including glucose and different low molecular weight (Mw) chito-oligosaccharides (COS) with varying acetylation degree (AD), on the extent of Maillard reaction (MR) on chitosan-based films were studied. Interestingly, an improvement of structural and functional properties of all MR-crosslinked films was noted, which is more pronounced by heating at higher temperature and exposure time. These findings were proved through Fourier-transform infrared and X-ray diffraction analyses. In addition, color change and Ultraviolet spectra demonstrate that glucose addition provides the high extent of MR, followed by COS1 (Mw < 4.4 kDa; AD, 18.20%) and COS2 (Mw < 4.4 kDa; AD, 10.63%). These results were confirmed by enhanced water resistance and thermal properties. Moreover, MR-chitosan/COS films showed the highest mechanical properties, whereas, glucose-loaded films were brittle, as demonstrated by scanning electron microscopy micrographs. Furthermore, MR-chitosan/COS1 films exhibited the better antioxidant behavior followed by chitosan/glucose and chitosan/COS2 films, mainly at higher heating-conditions. Thereby, MR-crosslinked chitosan/COS based films were attractive to be applied as functional and active coating-materials in various fields.


Assuntos
Quitosana , Antioxidantes , Glucose , Reação de Maillard , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Heliyon ; 7(10): e08099, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34632129

RESUMO

The physical and functional properties of gelatin-based films enriched with organic extracts from Lepidium sativum seeds were studied. Gelatin was extracted from the skin of dogfish (Squalus acanthias) and the functional gelatin-based films were used to preserve cheese during chilled storage. Ethanol extract (LSE3) and gelatin-based film enriched with LSE3 at 20 µg/mL showed high antioxidant potential using various complementary methods. No significant difference was measured in the mechanical parameters of the enriched films in terms of thickness, tensile strength and elongation at break. LSE3 incorporation at the highest level slighltly decreased the film L∗ value from 90.30 ± 0.10 to 88.10 ± 0.12, while the b∗ value increased from 0.91 ± 0.07 to 8.89 ± 0.12. Wrapping the cheese with gelatin-based film enriched with 20 µg LSE3/mL reduced the syneresis by 40% and stabilized the color, peroxidation and bacteria growth as compared to the unwrapped sample after 6 days of storage. In addition, cheese wrapped with the active gelatin-based film showed the lowest changes in texture parameters. Overall results suggest the use of the enriched gelatin film as active packaging material to preserve cheese quality.

4.
Int J Biol Macromol ; 182: 730-742, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33836191

RESUMO

The purpose of this study was to develop and characterize chitosan (Ch)-based films incorporated with varying molecular weight (Mw) and acetylation degree (AD) chitosan-depolymerization-products (CDP), to be applied as drug delivery materials. As compared to Ch-film, optical and antioxidant potentials of Ch/CDP-based films were improved, particularly using low Mw and AD-CDP. Whereas, films water resistance, mechanical and antibacterial properties increased as CDP-Mw increased and AD decreased. For the thermal and swelling behaviors, better values were obtained using higher Mw and AD-CDP. Further, to assess their in vitro ciprofloxacin (CFX)-release behavior, loaded-CFX Ch/CDP-based films, crosslinked using glutaraldehyde, were prepared. Expect of elongation at break, crosslinked CFX-loaded films showed increased optical, water resistance, tensile strength and thermal properties, as compared to unloaded films. The CFX-release profiles indicated that a slower and sustained release was observed, particularly when using lower Mw and AD-CDP, and mainly for the crosslinked films during 48 h. These films can release CFX for up to 54% in 6 and 24 h, at pH 1.2 and 7.4, respectively. Through this study, novel biodegradable, swellable and pH-sensitive crosslinked Ch/CDP-based films may be considered as suitable and promising drug delivery systems.


Assuntos
Antibacterianos/química , Antioxidantes/química , Quitosana/análogos & derivados , Portadores de Fármacos/química , Filmes Comestíveis , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Ciprofloxacina/administração & dosagem , Reagentes de Ligações Cruzadas/química , Portadores de Fármacos/farmacologia , Liberação Controlada de Fármacos , Glutaral/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Resistência à Tração
5.
Int J Biol Macromol ; 182: 1-10, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33775767

RESUMO

The current work aimed to prepare emulsion gels based on European eel skin gelatin (ESG). The results revealed that the ESG exhibited interesting antioxidant and functional properties in a dose-dependent manner. The ESG has a gel strength of 354.86 g and high gelling and melting temperatures of about 33 and 43 °C, respectively. Hence, based on its interesting gelling ability, the ESG-based gel was employed to stabilize European eel oil (EO) emulsions. In this context, two emulsions were prepared by homogenization or homogenization followed by sonication at EO:ESG weight ratios of 1:2 and 1:4. The physicochemical, textural, structural and thermal properties of emulsion gelatin-based gels (EGGs) were evaluated. The EGGs had a rigid and a cohesive gel network, according to the textural and microstructural analysis. Structural and thermogravimetric analyses showed the effective entrapment of EO in the ESG gel network.


Assuntos
Óleos de Peixe/química , Indústria Alimentícia/métodos , Gelatina/química , Géis/química , Animais , Enguias , Emulsões/química , Temperatura Alta , Oxirredução , Transição de Fase , Viscosidade
6.
Food Sci Nutr ; 9(3): 1551-1563, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33747469

RESUMO

A fucoidan, sulfated polysaccharide, was extracted from the brown seaweed Cystoseira schiffneri during 4 harvest periods (December, April, July, and September) and studied for its structural and chemical properties. The Cystoseira schiffneri fucoidan (CSF) showed important variation in sulfate content ranging from 7.8% in December to 34.8% in July. This was confirmed by Fourier transform infrared and nuclear magnetic resonance spectroscopies showing characteristic signals of sulfated polysaccharides. Molecular mass of the CSF varied as a function of season from 3,745 in December to 26,390 Da in July. Gas chromatography-mass spectroscopy showed that CSF fractions were "mannogalactofucans" composed mainly of mannose, fucose, and galactose with low levels of other monosaccharides. Moreover, interesting in vitro antioxidant activities that depend on the harvest season were noted for CSF. Thus, the present work might contribute to establish criteria for extracting bioactive fucoidans from an endemic Tunisian seaweed C. schiffneri.

7.
Carbohydr Polym ; 255: 117341, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33436184

RESUMO

This work focused on studying the physicochemical and antioxidant properties changes of varying molecular weight (Mw) chitosan-depolymerization products (CDP)-based films occurring after crosslinking by heat-treatment and Maillard reaction (MR). Based on color properties and browning index, an enhancement of films properties was observed after treatment at 90 °C with a reduction in their water content, solubility and contact angle. Brown MR products were developed in heated films containing glucose thus improving their barrier properties. This effect was more pronounced in lower Mw-CDP based films. In addition, according to TGA, EAB and TS analyses an improvement in heat-treated films thermal stability and mechanical properties was detected and further confirmed through FTIR, X-ray and SEM analyses. The evaluation of the antioxidant potential through four different assays allowed to conclude that glucose addition, thermal treatment and the use of low Mw-CDP highly enhanced the MR-modified films antioxidant capacity. Consequently, MR crosslinked chitosan-based films could be potentially used as an alternative for bioactive and functional packaging effective in food oxidation inhibition, especially using low Mw chitosan derivatives.

8.
Int J Mol Sci ; 22(3)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499004

RESUMO

This study reports on the purification and characterization of a digestive α-amylase from blue crab (Portunussegnis) viscera designated Blue Crab Amylase (BCA). The enzyme was purified to homogeneity by ultrafiltration, Sephadex G-100 gel filtration and Sepharose mono Q anion exchange chromatography, with the final purification fold of 424.02, specific activity of 1390.8 U mg-1 and 27.8% recovery. BCA, showing a molecular weight of approximately 45 kDa, possesses desirable biotechnological features, such as optimal temperature of 50 °C, interesting thermal stability which is enhanced in the presence of starch, high stability towards surfactants (Tween 20, Tween 80 and Triton X-100), high specific activity, quite high storage and broad pH range stability. The enzyme displayed Km and Vmax values, of 7.5 ± 0.25 mg mL-1 and 2000 ± 23 µmol min-1 mg-1 for potato starch, respectively. It hydrolyzed various carbohydrates and produced maltose, maltotriose and maltotetraose as the major end products of starch hydrolysis. In addition, the purified enzyme was successfully utilized for the improvement of the antioxidant potential of oat flour, which could be extended to other cereals. Interestingly, besides its suitability for application in different industrial sectors, especially food industries, the biochemical properties of BCA from the blue crab viscera provide novel features with other marine-derived enzymes and better understanding of the biodegradability of carbohydrates in marine environments, particularly in invasive alien crustaceans.


Assuntos
Antioxidantes/metabolismo , Avena/química , Braquiúros/enzimologia , Farinha , alfa-Amilases/metabolismo , Animais , Antioxidantes/química , Metabolismo dos Carboidratos , Cromatografia em Gel , Cromatografia por Troca Iônica , Cromatografia em Camada Fina , Concentração de Íons de Hidrogênio , Hidrólise , Íons , Cinética , Peso Molecular , Solanum tuberosum , Amido , Especificidade por Substrato , Tensoativos , Temperatura , Vísceras/enzimologia , alfa-Amilases/química
9.
Int J Biol Macromol ; 167: 1445-1451, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33212105

RESUMO

The present work aims to encapsulate goby fish protein hydrolysate (GPH), endowed with antioxidant activity, through ionic gelation process using blue crab chitosan (CH) and tripolyphosphate anions and to evaluate the structural, thermal and antioxidant properties of the elaborated microparticles (MPs). The GPH-loaded MPs present spherical shape as seen by scanning electron microscopy (SEM) images and positive zeta potential. The increase of loaded GPH concentration led to the increase of encapsulation efficiency (EE) and to the reduction of the particle size. In fact, MPs, loaded with 2 and 5 mg/ml GPH, had EE values of 44 and 58% and mean particles size of 4.81 and 3.78 µm, respectively. Furthermore, thermogravimetric analysis (TGA) profiles revealed the enhanced thermal stability of encapsulated biopeptides compared to the free ones. Release kinetic data showed a Fickian diffusion behavior which follows swelling and a diffusion-controlled mechanism for peptides liberation. Finally, as opposed to unloaded MPs, an improvement of the antioxidant activity of the loaded MPs with biopeptides was observed.


Assuntos
Antioxidantes/química , Braquiúros/química , Cápsulas/química , Quitosana/química , Sistemas de Liberação de Medicamentos/métodos , Peptídeos/química , Hidrolisados de Proteína/química , Animais , Ânions/química , Difusão , Peixes , Temperatura Alta , Cinética , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Polifosfatos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
10.
Int J Biol Macromol ; 167: 516-527, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33279565

RESUMO

A novel water-soluble polysaccharide named AGP1 was successfully isolated from seeds of Anethum graveolens by hot water extraction and further purified by DEAE-Sepharose chromatography. AGP1 has a relative molecular weight of 2.1 104 Da determined by Ultra-high-performance liquid chromatography (UHPLC). The AGP1 characterization was investigated by chemical and instrumental analysis including gas chromatography mass spectrometry (GC-MS), Fourier transform infrared (FT-IR) spectroscopy and X-ray diffraction. Results showed that AGP1 was mainly composed of glucose, galactose, mannose and arabinose in a molar percent of 54.3, 23.8, 14.7 and 7.2, respectively. The thermogravimetry analysis (TGA) and the differential scanning calorimetry (DSC) were used and showed that AGP1 has good thermal stability until 275 °C. Moreover, the purified polysaccharide demonstrated an appreciable in vitro antioxidant potential. The addition of the AGP1, particularly at 0.3% (w/w), in turkey sausages instead of ascorbic acid, as preservative, reduced the lipid peroxidation, preserved the pH and color and improved the bacterial stability during cold storage at 4 °C for 12 days. Overall, the results showed that the AGP1 deserves to be developed as functional and bioactive components for the food and nutraceutical industries.


Assuntos
Anethum graveolens/química , Antioxidantes/química , Conservantes de Alimentos/química , Polissacarídeos/química , Antioxidantes/farmacologia , Configuração de Carboidratos , Cromatografia Líquida de Alta Pressão , Suplementos Nutricionais , Conservantes de Alimentos/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Polissacarídeos/farmacologia , Sementes/química , Solubilidade , Termogravimetria
11.
Biomed Environ Sci ; 33(10): 760-770, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33228835

RESUMO

OBJECTIVE: This research was performed to evaluate the effect of tebuconazole (TBZ) on reproductive organs of male rats and to assess the protective role of combined essential trace elements in alleviating the detrimental effect of TBZ on male reproductive function. METHODS: For this purpose, 48 rats were exposed to 100 mg/kg TBZ, TBZ supplemented with zinc (Zn), selenium (Se), copper (Cu), and iron (Fe), TBZ + (Se + Zn); TBZ + Cu; or TBZ + Fe. The experiment was conducted for 30 consecutive days. RESULTS: TBZ caused a significant perturbation in mineral levels and reduction in reproductive organs weights, plasma testosterone level, and testicular antioxidant enzyme activities. The TBZ-treated group also showed a significant increase in sperm abnormalities (count, motility, and viability percent), plasma follicle-stimulating hormone and luteinizing hormone concentrations, lipid peroxidation, protein oxidation, and severe DNA degradation in comparison with the controls. Histopathologically, TBZ caused testis impairments. Conversely, treatment with trace elements, in combination or alone, improved the reproductive organ weights, sperm characteristics, TBZ-induced toxicity, and histopathological modifications in testis. CONCLUSION: TBZ exerts significant harmful effects on male reproductive system. The concurrent administration of trace elements reduces testis dysfunction, fertility, and toxicity induced by TBZ.


Assuntos
Antioxidantes/metabolismo , Fungicidas Industriais/efeitos adversos , Minerais/metabolismo , Espermatozoides/fisiologia , Testículo/efeitos dos fármacos , Oligoelementos/metabolismo , Triazóis/efeitos adversos , Ração Animal/análise , Animais , Dieta , Suplementos Nutricionais/análise , Masculino , Testes de Mutagenicidade , Ratos , Ratos Wistar , Espermatozoides/efeitos dos fármacos , Testículo/fisiologia , Oligoelementos/administração & dosagem
12.
Mater Sci Eng C Mater Biol Appl ; 116: 111164, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32806248

RESUMO

The present study investigates the potential of sardinelle protein isolate (SrPI) combined to maltodextrin (MD), at different ratios (1:0, 1:1, 1:2, 1:3 and 1:4, w/w), as wall matrix to stabilize and encapsulate corn oil (1:2, oil/ wall material ratio). Emulsions were prepared by homogenization followed by sonication treatment and then dried by the spray-drying process. The obtained microcapsules were characterized regarding the encapsulation efficiency (EE), scanning electron microscopy (SEM), infrared spectroscopy (FTIR), and thermodynamic analyses (thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC)). Data revealed that the combination of SrPI and MD resulted in very high EE compared to SrPI used alone as wall material, and the EE increased with the amount of MD incorporated to the SrPI solution. SEM images showed the production of irregular and larger particles with the increase of MD concentration. Moreover, TGA showed that microparticles obtained by 1:4 w/w ratio (SrPI/MD) displayed the highest protection of corn oil. Thus, these findings revealed the effectiveness of SrPI and MD mixture to encapsulate and protect corn oil, which offered a promote application for food and pharmaceutical industries.


Assuntos
Sonicação , Animais , Cápsulas , Composição de Medicamentos , Emulsões , Termogravimetria
13.
Environ Sci Pollut Res Int ; 27(31): 39402-39412, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32642904

RESUMO

The present study focused on the full valorization of the tomato by-product, also known as tomato pomace consisting mainly of tomato peels and tomato seeds, by recovering natural antioxidants and edible oil, and subsequently reutilizing the leftover solid residues for the production of low-cost biosorbent. The tomato peel extract recovered using ethanol as food-grade solvent contained high phenol and flavonoid contents (199.35 ± 0.35-mg gallic acid equivalents (GAE)/g and 102.10 ± 0.03-mg quercetin equivalent (QE)/g, respectively). Even its lower content of lycopene (3.67 ± 0.04 mg/100 g), tomato peel extract showed potent antioxidant activity and can be therefore used as natural antioxidants either for food or cosmetic applications. High nutritional quality edible oil (17.15%) was extracted from tomato seeds and showed richness in unsaturated fatty acids (74.62%), with linoleic acid being the most abundant polyunsaturated fatty acid (49.70%). After recovery of these valuable compounds, the extraction solid leftovers were used to produce low-cost biosorbent tested for dye removal. Results showed that the highest biosorption yields were increasingly attributed to the acidic, direct, anthraquinone, then reactive dyes. Overall, the obtained results strongly support the complete utilization of tomato pomace for the recovery of valuable compounds and the sequential production of low-cost biosorbent.


Assuntos
Solanum lycopersicum , Antioxidantes , Licopeno , Fenóis/análise , Extratos Vegetais , Sementes/química
14.
Carbohydr Polym ; 241: 116303, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32507187

RESUMO

This work aimed to modify blue crab chitosan-based films through the Maillard reaction (MR) as a novel alternative to improve their functional and biological properties. To this end, different saccharides (glucose (aldohexose), fructose (ketohexose), xylose (aldopentose) and arabinose (aldopentose)), at different weight ratios 0.5, 1.0 and 2.0 % (g/100 g polymer), were studied, and films were heated at 90 °C for 24 h. Based on color changes and browning index measurements, the extent of MR was the highest with aldopentoses, whereas hexoses and particularly ketohexoses, exhibited a relative crosslinking rate. These findings were further reflected with an improvement in treated films mechanical properties and thermal degradation temperatures, and advantageously, barrier properties against UV light and water. In addition, the MR-modified Cs-based films antioxidant activity was interestingly enhanced with mainly aldopentoses. Consequently, MR crosslinked chitosan-based films are promising alternative for active and functional packaging able of food oxidation hindering, especially using aldopentoses.


Assuntos
Braquiúros/química , Quitosana , Monossacarídeos/análise , Animais , Antioxidantes/análise , Quitosana/análogos & derivados , Quitosana/química , Embalagem de Alimentos , Reação de Maillard
15.
Int J Biol Macromol ; 162: 1-10, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32553953

RESUMO

The effects of two pretreatments (microwaves or oven-drying) on the dogfish (Squalus acanthias) skin as well as two drying processes (freeze-drying or spray-drying) on the extracted gelatins were studied. Thus six types of gelatins were obtained, three of which were freeze-dried (FG) and the others were spray-dried (SG), from the untreated skin (US), microwaves-pretreated skin (MS) and oven-pretreated skin (OS). The highest yield (8.67%) was obtained for the OSFG, while the lowest one (3.06%) was measured for the OSSG. Interestingly, all gelatins exhibited relatively high protein (84.02-89.53%), and low lipid (0.50-1.71%) and ash (3.05-7.17%) contents. In addition, gelatins were analyzed by the Fourier transform infrared and the spectra displayed important differences in some specific peaks, particularly in the amide I, amide II and amide III. The gelatins extracted from the untreated skin, regardless the drying method, presented the highest foaming capacity. The textural profile analysis showed that USSG was the hardest (213.6 g) and the chewier (23.8 N × mm) gelatin. Moreover, analysis of thermal properties showed that USSG also has the highest glass-transition temperature. The interesting properties of gelatin extracted from dogfish skin encourage their future use as a functional ingredient in industrial food formulations.


Assuntos
Dessecação/métodos , Cação (Peixe)/metabolismo , Liofilização/métodos , Gelatina/análise , Gelatina/isolamento & purificação , Pele/química , Amidas/análise , Aminoácidos/análise , Animais , Varredura Diferencial de Calorimetria , Cor , Gelatina/química , Gelatina/ultraestrutura , Géis/química , Dureza , Microscopia Eletrônica de Varredura , Micro-Ondas , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura de Transição
16.
Int J Biol Macromol ; 160: 593-601, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32485252

RESUMO

The present study was undertaken to establish a distinct relationship between blue crab chitosan (Cs) acetylation degree (AD) and molecular weight (Mw) and its structural features, thermal properties and bioactivity. Therefore, chitosans with different AD were prepared and Cellulase was used to produce Cs derivatives with decreasing Mw. Results clearly display a decrease of the ordered structure of Cs, with the increase of AD and the decrease of Mw. Thermal stability/degradation screening disclose a greater thermal resistance for Cs with lower AD and higher Mw. The anti-adhesive potential of Cs was, additionally, studied, as function of AD and Mw. The effectiveness of Cs in preventing biofilm adhesion was strongly influenced by its AD and Mw, with the lowest inhibition values for higher AD and lower Mw. Interestingly, the effectiveness of Cs in disrupting pre-formed biofilms increased with decreasing Mw. Moreover, Cs derivatives were found to be advantageously efficient in prolonging human blood clotting times, based on data of activated partial thromboplastin time, Quick time and thrombin time assays, typically for the intrinsic coagulation pathway. Accordingly, depending on the predicted application of Cs, either in food, biomedical and pharmaceutical industries, AD and Mw are critical traits to be inevitably reflected on.


Assuntos
Adesivos/química , Adesivos/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Braquiúros/química , Quitosana/química , Quitosana/farmacologia , Acetilação/efeitos dos fármacos , Animais , Biofilmes/efeitos dos fármacos , Humanos , Peso Molecular , Trombina/metabolismo
17.
Mater Sci Eng C Mater Biol Appl ; 113: 110978, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32487393

RESUMO

This work aimed to the development of chitosan and protein isolate composite hydrogels, for carotenoids-controlled delivery and wound healing. By increasing the concentration of the protein isolate, chitosan hydrogels were more elastic at a protein isolate concentration not exceeding 15% (w/w). Chitosan-protein isolate composite hydrogels revealed low cytotoxicity towards MG-63 osteosarcoma cells. Thanks to its appropriate structural, swelling and mechanical resistance properties, chitosan hydrogel (3%; w/v), reinforced with 15% (w/w) of protein isolate, was selected for the carotenoids in vitro release study. Release profiles, show delivery patterns, where carotenoids were more barely released at a pH 7.4 medium (p < .05), compared to more acidic microenvironments (pH 4.0 and pH 2.0). Thus, developed hydrogels could be applied as pH-sensitive intelligent carriers, for drugs-controlled release, with interesting antioxidant abilities. The in vivo healing potential of hydrogels in rats' models was further studied. Topical application of hydrogel-based patches allowed the acceleration of wound healing and the complete healing, for composite hydrogel enriched with carotenoids.


Assuntos
Materiais Biocompatíveis/farmacologia , Braquiúros/metabolismo , Carotenoides/química , Quitosana/química , Hidrogéis/química , Proteínas de Frutos do Mar/química , Cicatrização/efeitos dos fármacos , Animais , Antioxidantes/química , Materiais Biocompatíveis/química , Carotenoides/metabolismo , Carotenoides/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Humanos , Hidrogéis/metabolismo , Concentração de Íons de Hidrogênio , Ratos , Ratos Wistar , Solubilidade , Temperatura
18.
Carbohydr Polym ; 236: 116046, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32172860

RESUMO

Hydrogels properties open up many possibilities for medical applications. In the present study, protein drug insulin was selected as a model drug to test the in vitro release behavior of hydrogels based on blue crab chitosan (Cs) and red marine macroalga Falkenbergia rufolanosa polysaccharide (FRP). The FRP/Cs composed hydrogels were characterized in terms of structural, morphological, thermal and antioxidant properties. Data revealed that FRP addition enhanced the water holding capacity and the water uptake percentages, as well as the textural behavior. Moreover, the prepared hydrogels are simultaneous sensitive to pH, ionic strength and temperature as demonstrated in the swelling ratio test. Additionally, hydrogels at pH 1.2 PBS underwent greater degradation, compared to samples immersed in pH 7.4 PBS. Similarly, the kinetics of insuline release, through the FRP/Cs composed hydrogels exhibited higher released amounts in acidic systems. Through this study, the prepared hydrogels provided suitable and promising microenvironment in drugs delivery.


Assuntos
Quitosana/química , Portadores de Fármacos/química , Hidrogéis/química , Insulina/química , Polissacarídeos/química , Animais , Braquiúros/química , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/química , Portadores de Fármacos/síntese química , Liberação Controlada de Fármacos , Sequestradores de Radicais Livres/síntese química , Sequestradores de Radicais Livres/química , Hidrogéis/síntese química , Concentração de Íons de Hidrogênio , Rodófitas/química
19.
Carbohydr Polym ; 236: 116063, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32172878

RESUMO

The aim of this work was to explore the effect of various molecular weight (Mw) chitosan depolymerization products (CDP) on the silver nanoparticles (AgNPs) and chitosan/AgNPs blend films production. Produced AgNPs, stable during 30 days in a colloïdal form, were characterized in terms of UV-vis, transmission electron microscopy (TEM), dynamic light scattering (DLS) and fourier transform infrared spectroscopy (FTIR) analyses. AgNPs displayed interesting antibacterial and antioxidant properties that were affected by the physicochemical properties of used chitosans. Interestingly, CDP may be used for the preparation of bioactive and stable AgNPs. Additionally, chitosan/AgNPs blend films were prepared and characterized in terms of physiochemical and biological properties. As compared to the chitosan film, various properties were enhanced in the chitosan/AgNPs blend films, including light barrier, opacity, elongation at break, as well as bioactivities, thus suggesting that films could be used as novel alternative food packaging applications.


Assuntos
Antibacterianos/farmacologia , Quitosana/análogos & derivados , Sequestradores de Radicais Livres/farmacologia , Nanopartículas Metálicas/química , Prata/farmacologia , Antibacterianos/química , Bactérias/efeitos dos fármacos , Embalagem de Alimentos , Sequestradores de Radicais Livres/química , Química Verde , Testes de Sensibilidade Microbiana , Prata/química
20.
Biotechnol Prog ; 36(3): e2965, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31951103

RESUMO

This work deals with the optimization of the culture conditions of Bacillus invictae AH1 in order to increase the production level of the proteolytic activity. Response-surface methodology (RSM) was applied for the most significant fermentation parameters (concentration of wheat bran and K2 HPO4 /KH2 PO4 ) that were earlier identified by Plackett-Burman Design from seven possible factors. A central composite design was used and the quadratic regression model of producing active protease was built. A maximum protease activity was reached and validated experimentally, using a maximum wheat bran concentration (50 g/L) with increased K2 HPO4 /KH2 PO4 concentration (2.275 g/L). Protease production obtained experimentally coincident with the predicted value and the model was proven to be adequate. Interestingly, the use of RSM increased the protease production by four times (7,000 U/mL) using a low-cost substrate and a culture time of 40 hr, as compared to the standard culture conditions. In the second part of this study, a H2 O2 -tolerant alkaline protease produced from B. invictae AH1 with a molecular mass of about 41 kDa, noted P3, was purified by successive steps of ultrafiltration, gel filtration and ion exchange chromatography. The K m and Vmax values of the purified protease using casein, as substrate, were about 4 mg/mL and 27 µM/min, respectively. The highest enzyme activity was found at pH 9.0 and a temperature of 60°C. In addition, the enzyme showed a quasi-total stability against H2 O2 (5% for 1 hr) and against most of the tested solid and liquid detergents, suggesting its eventual use in bio-detergent formulations.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Caseínas/química , Meios de Cultura/química , Endopeptidases/isolamento & purificação , Peróxido de Hidrogênio/farmacologia , Bacillus/enzimologia , Proteínas de Bactérias/química , Cromatografia em Gel , Cromatografia por Troca Iônica , Meios de Cultura/farmacologia , Fibras na Dieta/metabolismo , Endopeptidases/química , Fermentação , Peróxido de Hidrogênio/efeitos adversos , Propriedades de Superfície/efeitos dos fármacos
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