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1.
Food Chem ; 457: 140132, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38917570

RESUMO

The clarification conditions and the selection of the clarification agent are pivotal in eliminating the haze components from red grape juice (RGJ) while minimizing the loss of functional color components. In this context, we synthesized a water glass-based APTES functionalized magnesium silica aerogel (MSA-NH3) incorporating 61.44 molecules/nm2 of amine groups, resulting in a positively charged zeta potential value of 33.9 mV (pH 3.4) for clarification of RGJ by targeting negatively charged polyphenols. The optimum clarification conditions using MSA-NH3 were determined as 0.18 g MSA-NH3/L RGJ, 20 °C, and 60 min through the application of Box-Behnken design. Under these conditions, MSA-NH3 exhibited excellent adsorption of haze components (3.61 NTU), outperforming the commercial bentonite-gelatine combination (BGC) (5.45 NTU). Furthermore, it exhibited greater efficacy in preserving anthocyanins while adsorbing browning components. MSA-NH3 has a high potential to serve as a functional alternative clarification agent in the beverage industry due to its promising clarification performance.

2.
ACS Omega ; 9(19): 21187-21203, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38764625

RESUMO

This study reports the fabrication and characterization of poly(vinyl alcohol) (PVA) and gelatin (Gel)-based nanofiber membranes cross-linked with citric acid (CA) by a green electrospinning method in which nano 45S5 bioglass (BG) and urea were incorporated. Various combinations of PVA, gelatin, and BG were prepared, and nanofiber membranes with average fiber diameters between 238 and 595 nm were fabricated. Morphological, chemical, and mechanical properties, porosity, swelling, water retention, and water vapor transmission rate of the fabricated membranes were evaluated. PVA:Gel (90:10), 15% CA, and 3% BG were determined as the optimum blend for nanofiber membrane fabrication via electrospinning. The membrane obtained using this blend was further functionalized with 10% w/w polymer urea coating by the electrospray method following the cross-linking. In vitro biocompatibility tests revealed that the fabricated membranes were all biocompatible except for the one that functionalized with urea. In vivo macroscopic and histopathological analysis results of PVA/Gel/BG and PVA/Gel/BG/Urea treated wounds indicated increased collagenization and vascularization and had an anti-inflammatory effect. Furthermore, careful examination of the in vivo macroscopic results of the PVA/Gel/BG/Urea membrane indicated its potential to decrease uneven scar formation. In conclusion, developed PVA/Gel/BG and PVA/Gel/BG/Urea electrospun membranes with multifunctional and biomimetic features may have the potential to be used as beneficial wound dressings.

3.
ACS Omega ; 9(18): 20243-20252, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38737063

RESUMO

This research explores the crystallization process of honey during storage with a focus on its dissolution dynamics and essential characteristics. The investigation includes the examination of the effects of heat treatment at different temperatures (45-90 °C) and durations (23-960 min) on the induced crystallization of honey at 14 °C. Various analyses were conducted, including pH, acidity, color, sugar profile, phenolic and flavonoid contents, DPPH-scavenging activity, hydroxymethylfurfural (HMF), viscosity, and sensory attributes. The results indicated a reduction in the moisture content and pH, an increase in acidity, and higher levels of HMF at elevated temperatures. While the ash content remained relatively unchanged, variables such as color, glucose, fructose, total phenol, flavonoid, and antioxidant content exhibited variations with temperature. Viscosity decreased with an increase in temperature, suggesting Newtonian behavior and implying potential colloidal changes. Consumer sensory tests revealed significant differences among samples, with honey treated at 75 °C demonstrating superior physicochemical and sensory attributes. This study offers valuable insights into the dynamics of crystallized honey, providing information for both production practices and understanding consumer preferences.

4.
Polymers (Basel) ; 16(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38399911

RESUMO

In bone tissue engineering, scaffold attributes such as pore dimensions and mechanical strength are crucial. This study synthesized polycaprolactone dimethacrylate (PCLDMA) from polycaprolactone (PCL), incorporating epichlorohydrin (Epi-PCL) and methacryloyl chloride (Meth-Cl). PCLDMA was blended with polylactic acid (p-PLA) to 3D-print bone scaffolds using stereolithography (SLA). Analytical techniques included nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and compression testing. Degradation kinetics and cell viability were investigated using human osteoblast (HOB) cells. Findings revealed PCLDMA/p-PLA composite scaffold superiority over the original polymers. Notably, PCLDMA-60 (60% PCLDMA, 40% p-PLA) displayed optimal properties. Compressive strength varied from 0.019 to 16.185 MPa, porosity from 2% to 50%, and degradation rates from 0% to 0.4% over three days. Cell viability assays affirmed biocompatibility across various PCLDMA ratios. In conclusion, PCLDMA/p-PLA composite scaffolds, particularly PCLDMA-60, show great potential in bone tissue engineering.

5.
ACS Omega ; 8(38): 34448-34457, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37779931

RESUMO

Okra (Abelmoschus esculentus L.) is known for its high nutritional value, including its content of phytochemicals. This study aims to investigate the effect of drying and freezing conditions on the phytochemical content of okra. Our results indicated that both air-drying and freezing okra during 6 months of storage showed a significant decrease in total phenolic content, flavonoid content, anthocyanin content, and antioxidant activity. Furthermore, higher levels of phytochemicals were found for okra samples treated with Na2SO4 solution when compared to untreated okra. The freezing process appeared to better preserve the content of the investigated phytochemicals when compared to the decrease after drying. Our research has determined that both immersing and freezing okra samples consistently yielded better results in the preservation of phytochemical properties over time, compared to other methods. This study is important for the food industry, as it highlights the importance of proper storage methods to retain the nutritional value of okra.

6.
ACS Omega ; 8(37): 33857-33869, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37744791

RESUMO

Photocatalysis reactions are of great interest as an effective tool against the profusely increasing population of antibiotic-resistant bacteria species. In particular, the promising evidence on plasmon-sensitized titanium dioxide (TiO2) photocatalysis inspired us to investigate their antibacterial activity stemming from the photogenerated reactive oxygen species (ROS). Herein, TiO2 nanostructures were grown in situ within a silica (SiO2) aerogel matrix with high surface area and porosity, and their ROS-related phototoxic effects against Escherichia coli bacteria were investigated under solar- and visible-light irradiations. Photodegradation profiles obtained from Rhodamine B (RhB) organic dye used as a chemical probe proved that the types of ROS produced by SiO2/TiO2 aerogels varied depending on the electromagnetic spectrum portion that was used during material irradiation. Further, the SiO2/TiO2 aerogel matrix was decorated with silver-gold nanostars (Ag@Au NSs) to enhance its photocatalytic efficiency under visible light irradiations. Our design showed that plasmon-enriched composite aerogels efficiently boosted ROS production under visible light exposures and that the structures containing Ag@Au NSs showed a much more effective antibacterial effect compared to their counterparts.

7.
Cureus ; 15(7): e41521, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37551216

RESUMO

Background Bone is a dramatically regenerating tissue with the ability to heal after trauma, although intensive surgical management is required to treat considerable damage. In this study, 45S5 bioactive grafts were prepared through the melt-quenched method in compliance with the guidelines on medical product requirements (MDD regulations; 93/42/EEC Annex-II section 3&4 and ISO standardizations; ISO 13485:2016) for bone repair and regeneration. Methodology After preparing the graft/scaffold, it was evaluated for biocompatibility according to the principles of "lSO 10993-6 2015 Biological evaluation of medical devices: Tests for local effects after implantation, Annex D 'Test method for implantation in bone,'" "lSO 10993-2:2005 Biological evaluation of medical devices: Animal welfare requirements," and "lSO 10993-12 2012 Biological evaluation of medical devices sample preparation rules and standards." Defects were created on the tibia of the right hind leg. The defects were filled with 3-mm bioactive granules, and a cylindrical polypropylene biocompatible material was used as a negative control. After 120 days, the sheep were sacrificed, and the tibia were analyzed. Results The results demonstrated the safety of 45S5 bioactive grafts. Histological evaluation showed no signs of pathological changes around the implant area. Hematoxylin and eosin sections demonstrated the presence of a few multinucleated giant cells, macrophages, and non-irritant mild fibrotic changes on the surface of the biomaterial. Conclusions 45S5 bioactive glass was found to be biocompatible in a sheep model, demonstrating its capacity to promote bone consolidation while also justifying its further preclinical application as a bone-bonded material owing to the layer formation of the growing bone mineral.

8.
Biopolymers ; 114(10): e23562, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37421643

RESUMO

Polymeric barrier membranes are used in periodontal applications to prevent fibroblastic cell migration into the cavities of bone tissue and to properly guide the proliferation of tissues. In this study, the fabrication, characterization, bioactivity, and in vitro biological properties of polyvinyl alcohol-based nanofibrous membranes containing nano-sized 45S5 bioactive glass (BG) loaded with chlorhexidine (CH) gluconate with biocompatible, bioactive, and antibacterial properties for using as dental barrier membranes were investigated. Nanofibrous membranes with an average fiber diameter, pore size, and porosity of 210 nm, 24.73 µm, and 12.42%, respectively, were loaded with 1% and 2% CH, and the release profile was investigated. The presence of BG in the membranes promoted fibroblastic proliferation and the presence of CH provided antibacterial properties. Nanofibrous membranes exhibit a high ability to restrict bacterial growth while fulfilling the necessary conditions for use as a dental barrier thanks to their low swelling rates, significant surface bioactivities, and appropriate degradation levels.


Assuntos
Regeneração Tecidual Guiada , Nanofibras , Álcool de Polivinil/farmacologia , Clorexidina/farmacologia , Regeneração Óssea , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia
9.
Int J Biol Macromol ; 242(Pt 2): 124901, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37210057

RESUMO

The application of powder or granule formed bioactive glasses in the defect area with the help of a liquid carrier to fill the defects is a subject of interest and is still open to development. In this study, it was aimed to prepare biocomposites of bioactive glasses incorporating different co-dopants with a carrier biopolymer and to create a fluidic material (Sr and Zn co-doped 45S5 bioactive glassessodium hyaluronate). All biocomposite samples were pseudoplastic fluid type, which may be suitable for defect filling and had excellent bioactivity behaviors confirmed by FTIR, SEM-EDS and XRD. Biocomposites with Sr and Zn co-doped bioactive glass had higher bioactivity considering the crystallinity of hydroxyapatite formations compared to biocomposite with undoped bioactive glasses. Biocomposites with high bioactive glass content had hydroxyapatite formations with higher crystallinity compared to biocomposites with low bioactive glass. Furthermore, all biocomposite samples showed non-cytotoxic effect on the L929 cells up to a certain concentration. However, biocomposites with undoped bioactive glass showed cytotoxic effects at lower concentrations compared to biocomposites with co-doped bioactive glass. Thus, biocomposite putties utilizing Sr and Zn co-doped bioactive glasses may be advantageous for orthopedic applications due to their specified rheological, bioactivity, and biocompatibility properties.


Assuntos
Ácido Hialurônico , Zinco , Estrôncio , Vidro , Durapatita
10.
ACS Omega ; 8(12): 11479-11491, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37008093

RESUMO

In this study, mesoporous calcium silica aerogels were produced for use as an anticaking food additive in powdered foods. A low-cost precursor (sodium silicate) was used, and calcium silica aerogels with superior properties were obtained with different pH values (pH 7.0 and pH 9.0) by modeling and optimizing the production process. The Si/Ca molar ratio, reaction time, and aging temperature were determined as independent variables, and their effects and interactions to maximize the surface area and water vapor adsorption capacity (WVAC) were evaluated by response surface methodology and analysis of variance. Responses were fitted with a quadratic regression model to find optimal production conditions. Model results showed that the maximum surface area and WVAC of the calcium silica aerogel that was produced with pH 7.0 were achieved at a Si/Ca molar ratio of 2.42, a reaction time of 5 min, and an aging temperature of 25 °C. The surface area and WVAC of calcium silica aerogel powder produced with these parameters were found to be 198 m2/g and 17.56%, respectively. According to the results of surface area and elemental analysis, calcium silica aerogel powder produced at pH 7.0 (CSA7) had the best results compared to that produced at pH 9.0 (CSA9). Therefore, detailed characterization methods were examined for this aerogel. The morphological review of the particles was performed with scanning electron microscopy. Elemental analysis was performed via inductively coupled plasma atomic emission spectroscopy. True density was measured in a helium pycnometer, and tapped density was calculated by the tapped method. Porosity was calculated using an equation using these two density values. The rock salt was powdered with a grinder and used as a model food for this study, and CSA7 was added at a rate of 1% by weight. The results showed that adding CSA7 powder to the rock salt powder at a rate of 1% (w/w) improved the flow behavior from the cohesive region to the easy-flow region. Consequently, calcium silica aerogel powder with a high surface area and high WVAC might be considered as an anticaking agent to use in powdered foods.

11.
Bioact Mater ; 5(1): 66-73, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31989060

RESUMO

The objective of this study was to investigate the effect of magnesium (1 wt%) and aluminum (1 wt%) incorporation on the in vitro bioactivity and biodegradation behavior of 45S5 bioactive glasses synthesized from rice husk biogenic silica. The performance of biogenic silica-based samples was compared well with commercial silica-based counterparts. The in vitro biodegradation behavior of bioactive glasses was evaluated by the weight loss of samples and pH variation in the Tris buffer solution. Based on composition, bioglasses possessed different properties before and after simulated body fluid (SBF) immersion. The incorporation of magnesium (Mg) and aluminum (Al) enhanced the Vickers hardness of bioglasses. All the bioglasses showed the hydroxyapatite layer formation after SBF treatment as confirmed by the dissolution, FTIR, SEM and XRD analysis, however it was more prominent in the rice husk silica-based 45S5 bioglass. The biogenic silica seems to be a promising starting material for bioglass systems to be used in bone tissue engineering applications.

12.
Biol Trace Elem Res ; 189(1): 277-290, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30146669

RESUMO

In this study, mineral nutrient and heavy metal (Al, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Zn) contents of the walnut kernels and their co-located soil samples collected from the four different zones of natural walnut forests (Sary-Chelek, Arslanbap, and Kara-Alma in Jalal-Abad Region and Kara-Shoro in Osh Region) in Kyrgyzstan were investigated. The highest concentrations for all elements determined in the soil samples were observed in the Sary-Chelek zone whereas the Arslanbap zone was found to be having the lowest concentrations except Fe and Zn. The highest concentrations in the kernels of walnut samples were found to be in the Sary-Chelek zone for Ca, Fe, K, Mg, and Zn; in the Kara-Shoro zone for Cu; in the Arslanbap zone for Mn; and in the Kara-Alma zone for Na whereas the lowest concentrations were found to be in the Arslanbap zone for Ca, Fe, K, Mg, Na, and Zn and in the Sary-Chelek zone for Cu and Mn, respectively. Also, the levels of Al, Cd, Ni, and Pb in kernel samples could not be detected by ICP-OES because their levels were lower than the threshold detection point (10 µg.kg-1). Additionally, our data indicated that the walnut kernels from Kyrgyzstan have higher values for RDA (recommended daily allowances) in comparison with the walnut kernels from other countries.


Assuntos
Juglans/química , Metais Pesados/análise , Minerais/química , Monitoramento Ambiental
13.
Biotechnol Lett ; 40(7): 1135-1147, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29777512

RESUMO

OBJECTIVES: To identify a robust NADP+ dependent formate dehydrogenase from Lactobacillus buchneri NRRL B-30929 (LbFDH) with unique biochemical properties. RESULTS: A new NADP+ dependent formate dehydrogenase gene (fdh) was cloned from genomic DNA of L. buchneri NRRL B-30929. The recombinant construct was expressed in Escherichia coli BL21(DE3) with 6 × histidine at the C-terminus and the purified protein obtained as a single band of approx. 44 kDa on SDS-PAGE and 90 kDa on native-PAGE. The LbFDH was highly active at acidic conditions (pH 4.8-6.2). Its optimum temperature was 60 °C and 50 °C with NADP+ and NAD+, respectively and its Tm value was 78 °C. Its activity did not decrease after incubation in a solution containing 20% of DMSO and acetonitrile for 6 h. The KM constants were 49.8, 0.12 and 1.68 mM for formate (with NADP+), NADP+ and NAD+, respectively. CONCLUSIONS: An NADP+ dependent FDH from L. buchneri NRRL B-30929 was cloned, expressed and identified with its unusual characteristics. The LbFDH can be a promising candidate for NADPH regeneration through biocatalysis requiring acidic conditions and high temperatures.


Assuntos
Proteínas de Bactérias/química , Formiato Desidrogenases/química , Lactobacillus/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Clonagem Molecular , Estabilidade Enzimática , Escherichia coli/genética , Formiato Desidrogenases/genética , Formiato Desidrogenases/metabolismo , Concentração de Íons de Hidrogênio , Lactobacillus/genética , NADP/metabolismo , Temperatura
14.
Water Sci Technol ; 75(2): 358-365, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28112663

RESUMO

The main objective of the present study was to optimize lead adsorption onto zeolite NaA. For this purpose, to synthesize zeolite NaA under hydrothermal conditions, local wheat husk was precleaned with chemical treatment using hydrochloric acid solution. The unmodified (ZU) and NaCl-modified (ZN) zeolites were characterized by Brunauer-Emmett-Teller, scanning electron microscopy coupled with energy dispersive spectroscopy and X-ray diffraction. The optimization of adsorption process was examined using Box-Behnken Experimental Design in response surface methodology by Design Expert Version 7.0.0 (Stat-Ease, USA). The effects of initial lead (II) concentration, temperature, and time were selected as independent variables. Lack of fit test indicates that the quadratic regression model was significant with the high coefficients of determination values for both adsorbents. Optimum process conditions for lead (II) adsorption onto ZU and ZN were found to be 64.40°C and 64.80°C, respectively, and 90.80 min, and 350 mg L-1 initial lead(II) concentration for both adsorbents. Under these conditions, maximum adsorption capacities of ZU and ZN for lead (II) were 293.38 mg g-1 and 321.85 mg g-1, respectively.


Assuntos
Chumbo/química , Modelos Químicos , Poluentes Químicos da Água/química , Zeolitas/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética
15.
Mater Sci Eng C Mater Biol Appl ; 68: 350-357, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27524030

RESUMO

Bioactive glass scaffolds that contain silica are high viable biomaterials as bone supporters for bone tissue engineering due to their bioactive behaviour in simulated body fluid (SBF). In the human body, these materials help inorganic bone structure formation due to a combination of the particular ratio of elements such as silicon (Si), calcium (Ca), sodium (Na) and phosphorus (P), and the doping of strontium (Sr) into the scaffold structure increases their bioactive behaviour. In this study, bioactive glass scaffolds were produced by using rice hull ash (RHA) silica and commercial silica based bioactive glasses. The structural properties of scaffolds such as pore size, porosity and also the bioactive behaviour were investigated. The results showed that undoped and Sr-doped RHA silica-based bioactive glass scaffolds have better bioactivity than that of commercial silica based bioactive glass scaffolds. Moreover, undoped and Sr-doped RHA silica-based bioactive glass scaffolds will be able to be used instead of undoped and Sr-doped commercial silica based bioactive glass scaffolds for bone regeneration applications. Scaffolds that are produced from undoped or Sr-doped RHA silica have high potential to form new bone for bone defects in tissue engineering.


Assuntos
Substitutos Ósseos/química , Vidro/química , Dióxido de Silício/química , Estrôncio/química , Alicerces Teciduais/química , Regeneração Óssea , Humanos
16.
Artif Cells Nanomed Biotechnol ; 44(2): 710-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25650647

RESUMO

This paper describes the formulation of archaeosomes and the evaluation of their abilities to facilitate in vitro DNA delivery. Lipids of the H.hispanica 2TK2 strain were used in archaeosome formation, which is formulated by mixing H.hispanica 2TK2 lipids with plasmid DNA encoding green fluorescent protein (GFP) or ß-galactosidase (ß-gal). Archaeosome/pDNA formation and unbound DNA were monitored by agarose gel electrophoresis. The archaeosome formulations were visualized by AFM and TEM. The zeta potential analysis showed the archaeosomes to be electronegative. The composition of archaeosomes and the DNA dose for transient transfection into HEK293 cells were optimized, and the relationship between the structure and activity of archaeosomes in DNA delivery was investigated. By themselves, archaeosomes showed low efficiency for DNA delivery, due to their anionic nature. By formulating archaeosomes with a helper molecule, such as DOTAP, CaCl2, or LiCl, the capability of archaeosomes for gene transfection is significantly enhanced. The transfection profiles of efficient archaeosomes are proved to have a long shelf-life when maintained at room temperature. Thus, the archaeal lipids have the potential to be used as transfection reagents in vitro.


Assuntos
DNA/química , DNA/genética , Portadores de Fármacos/química , Haloarcula/química , Plasmídeos/genética , Transfecção/métodos , DNA/administração & dosagem , Células HEK293 , Humanos , Lipossomos
17.
Braz. arch. biol. technol ; 55(5): 677-683, Sept.-Oct. 2012. tab
Artigo em Inglês | LILACS | ID: lil-651650

RESUMO

The proximate composition of eleven walnut (Juglans regia L.) genotypes (28 ŞK 010, 28 ŞK 055, 28 ŞK 041, 28 ŞK 601, 28 ŞK 925, 28 ŞK 028, 28 ŞK 118, 28 ŞK 350, 28 ŞK 930, 28 ŞK 850, 28 ŞK 036) and three walnut cultivars (Şebin, Bilecik, Kaman 1) produced in Turkey were determined. The oil content of the samples ranged from 61.32 to 69.35%, corresponding to an energy value of approximately 710 kcal per 100 g of kernel. The protein content ranged from 10.58 to 18.19%, and the carbohydrate composition was between 9.05 and 18.92%. The ash content ranged from 1.53 to 1.99%, and the moisture content of the kernels was between 1.91 and 4.48% the oleic acid content of the oils ranged from 17.90 to 33.35% of the total fatty acids. The linoleic acid content ranged from 43.15 to 60.20%. The linolenic acid content ranged from 9.98 to 13.00%. The palmitic acid content was between 5.21 and 8.40%. Stearic acid ranged from 2.36 to 4.25%. Potassium was the major mineral in all the samples, ranging from 359.73 to 482.97 mg/100 g. Calcium was the next most abundant mineral, ranging from 109.45 to 335.97 mg/100 g, followed by magnesium, ranging from 126.01 to 165.15 mg/100 g.

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