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1.
Phys Med Biol ; 69(10)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38565123

RESUMEN

Objective.To evaluate the reduction in energy dependence and aging effect of the lithium salt of pentacosa-10,-12-diynoic acid (LiPCDA) films with additives including aluminum oxide (Al2O3), propyl gallate (PG), and disodium ethylenediaminetetracetate (EDTA).Approach. LiPCDA films exhibited energy dependence on kilovoltage (kV) and megavoltage (MV) photon energies and experienced deterioration over time. Evaluations were conducted with added Al2O3and antioxidants to mitigate these issues, and films were produced with and without Al2O3to assess energy dependence. The films were irradiated at doses of 0, 3, 6, and 12 cGy at photon energies of 75 kV, 105 kV, 6 MV, 10 MV, and 15 MV. For the energy range of 75 kV to 15 MV, the mean and standard deviation (std) were calculated and compared for the values normalized to the net optical density (netOD) at 6 MV, corresponding to identical dose levels. To evaluate the aging effect, PG and disodium EDTA were incorporated into the films: sample C with 1% PG, sample D with 2% PG, sample E with 0.62% disodium EDTA added to sample D, and sample F with 1.23% disodium EDTA added to sample D.Main results. Films containing Al2O3demonstrated a maximum 15.8% increase in mean normalized values and a 15.1% reduction in std, reflecting a greater netOD reduction at kV than MV energies, which indicates less energy dependence in these films. When the OD of sample 1-4 depending on the addition of PG and disodium EDTA, was observed for 20 weeks, the transmission mode decreased by 8.7%, 8.3%, 29.3%, and 27.3%, respectively, while the reflection mode was 5.4%, 3.0%, 37.0%, and 34.5%, respectively.Significance. Al2O3effectively reduced the voltage and MV energy dependence. PG was more effective than disodium EDTA in preventing the deterioration of film performance owing to the aging effect.


Asunto(s)
Dosimetría por Película , Dosimetría por Película/instrumentación , Dosimetría por Película/métodos , Óxido de Aluminio/química , Ácido Edético/química , Galato de Propilo , Fotones
2.
Insects ; 15(4)2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38667386

RESUMEN

In recent years, the number of available chemical pesticides has been dramatically reduced, urging the need for the discovery of alternatives to chemical pesticide products such as, among others, natural zeolites (zeolitic rocks). We determined the mineralogical and chemical composition of a specific and continuous layer of zeolitic rock sample (ZeotP) from Petrota, Evros, Greece, and evaluated its oviposition-deterrent effect on the olive fruit fly Bactrocera oleae Gmelin (Diptera: Terphritidae). The tested natural zeolite contained 70 wt. % clinoptilolite, 18 wt. % amorphous material, 7 wt. % feldspars, 4 wt. % cristobalite, and 1 wt. % quartz. We tested the oviposition-deterrent effect of ZeotP mixed or not with an emulsifier adjuvant, NU-FILM-P®, in water and applied it to the surface of olive fruits. The ZeotP oviposition-deterrent effect on the olive fly was very high under a series of tested temperatures (17 °C, 20 °C, 25 °C, and 30 °C) and RHs (23%, 33%, 55%, 75%, and 94%). In addition, the ZeotP residual deterrent effect after equable water spraying was high, like the respective effect of the pyrethroid insecticide Decis® (deltamethrin). Our results may contribute to the effective control of the olive fruit fly using an alternative to chemical pesticides: natural zeolite (zeolitic rocks) products.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38668751

RESUMEN

p-type thin-film transistors (pTFTs) have proven to be a significant impediment to advancing electronics beyond traditional Si-based technology. A recent study suggests that a thin and highly crystalline Te layer shows promise as a channel for high-performance pTFTs. However, achieving this still requires specific conditions, such as a cryogenic growth temperature and an extremely thin channel thickness on the order of a few nanometers. These conditions critically limit the practical feasibility of the fabrication process. Here, we report a high-performance pTFT incorporating a 60-nm-thick highly crystalline Se-Te alloyed channel layer, produced using pulsed laser ablation at room temperature. The Se0.5Te0.5 alloy system enhances crystalline temperature and widens the band gap compared to a pure Te channel. Consequently, this approach results in a field-effect mobility of 3 cm2/V·s, with an on/off current ratio of 3 × 105, a subthreshold slope of 2.1 V/decade, and a turn-on voltage of 6.5 V, achieved through conventional annealing at 250 °C. To demonstrate its applicability in complementary circuit applications, we integrate a complementary-type inverter using a p-type Se0.5Te0.5 TFT and an n-type Al-doped InZnSnO, demonstrating a high voltage gain of 12 and a low static power consumption of 17 nW. This suggests that the Se-Te alloyed channel approach paves the way to a more straightforward and cost-effective process for Te-based pTFT devices and their applications.

4.
Prog Retin Eye Res ; 100: 101250, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38460758

RESUMEN

Changes in the bacterial flora in the gut, also described as gut microbiota, are readily acknowledged to be associated with several systemic diseases, especially those with an inflammatory, neuronal, psychological or hormonal factor involved in the pathogenesis and/or the perception of the disease. Maintaining ocular surface homeostasis is also based on all these four factors, and there is accumulating evidence in the literature on the relationship between gut microbiota and ocular surface diseases. The mechanisms involved are mostly interconnected due to the interaction of central and peripheral neuronal networks, inflammatory effectors and the hormonal system. A better understanding of the influence of the gut microbiota on the maintenance of ocular surface homeostasis, and on the onset or persistence of ocular surface disorders could bring new insights and help elucidate the epidemiology and pathology of ocular surface dynamics in health and disease. Revealing the exact nature of these associations could be of paramount importance for developing a holistic approach using highly promising new therapeutic strategies targeting ocular surface diseases.


Asunto(s)
Microbioma Gastrointestinal , Homeostasis , Humanos , Microbioma Gastrointestinal/fisiología , Homeostasis/fisiología , Oftalmopatías/microbiología
5.
Carbohydr Polym ; 334: 122043, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38553239

RESUMEN

Here, we prepared ionically crosslinked films using pectin extracted from agro-wastes, specifically ambarella peels (AFP) and jackfruit seed slimy sheath (JFS). Physiochemical properties of pectins, including moisture content, molecular weight (Mw), degree of esterification (DE), and galacturonic acid (GA), were analyzed. Optimal extraction was determined, i.e., citric acid concentration 0.3 M, time 60 min, solid/liquid ratio 1:25, and temperature 90 °C for AFP or 85 °C for JFS. Pectin yields under these conditions were 29.67 % ± 0.35 % and 29.93 ± 0.49 %, respectively. AFP pectin revealed Mw, DE, and GA values of 533.20 kDa, 67.08 % ± 0.68 %, and 75.39 ± 0.82 %, while JFS pectin exhibited values of 859.94 kDa, 63.04 % ± 0.47 %, and 78.63 % ± 0.71 %, respectively. The pectin films crosslinked with Ca2+, Cu2+, Fe3+, or Zn2+ exhibited enhanced tensile strength and Young's modulus, along with reduced elongation at break, moisture content, water solubility, water vapor permeability, and oxygen permeability. Structural analyses indicated metal ions were effectively crosslinked with carboxyl groups of pectin. Notably, the Cu2+-crosslinked film demonstrated superior water resistance, mechanical properties, and exhibited the highest antioxidant and antibacterial activities among all tested films. Therefore, the pectin films represent a promising avenue to produce eco-friendly food packaging materials with excellent properties.


Asunto(s)
Artocarpus , Pectinas , Artocarpus/química , Embalaje de Alimentos , Frutas/química , Iones/análisis , Pectinas/química , Semillas
6.
Int J Biol Macromol ; 264(Pt 1): 130626, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38453123

RESUMEN

Silver-Carrageenan (Ag/Carr) nanocomposite film for food packing application by the green method using Argemone albiflora leaf extract has been developed in this study. Different plant parts of Argemone albiflora (blue stem prickly poppy) are used all over the world for the treatment of microbial infections, jaundice, skin diseases etc. GC-MS analysis was used to examine the phytochemical found in the Argemone albiflora leaf extract which reduces the metal ions to nanoscale. The biopolymer employed in the synthesis of nanocomposite film was carrageenan, a natural carbohydrate (polysaccharide) extracted from edible red seaweeds. We developed a food packing that is biodegradable, eco-friendly, economical and free from harmful chemicals. These films possess better UV barrier and mechanical and antimicrobial properties with 1 mM AgNO3 solution. The presence of silver nanoparticles in the carrageenan matrix was evident from FESEM. The mechanical properties were analysed by a Universal testing machine (UTM) and different properties like water vapour permeability (WVP), moisture content (MC) and total soluble matter (TSM) important for food packing applications were also analysed. The antimicrobial properties of the synthesized film samples were studied against E. coli and S. aureus pathogenic bacteria. These films were employed for the storage of cottage cheese (dairy product) and strawberries (fruit). This packing increased the shelf life of the packed food effectively. Ag/Carr films are biodegradable within four weeks.


Asunto(s)
Antiinfecciosos , Argemone , Nanopartículas del Metal , Nanocompuestos , Carragenina/química , Plata/química , Embalaje de Alimentos , Nanopartículas del Metal/química , Escherichia coli , Staphylococcus aureus , Antiinfecciosos/farmacología , Antiinfecciosos/química , Nanocompuestos/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Antibacterianos/farmacología , Antibacterianos/química
7.
Int J Biol Macromol ; 266(Pt 2): 131001, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38547951

RESUMEN

The main objective of this work is to develop biodegradable active films through the combination of the extracts with different solvents sourced from Eucalyptus citriodora leaves, with films made of chitosan (Cs) and polyvinylpyrrolidone (PVP). Chromatographic profiling investigations were carried out to examine the antibacterial characteristics of E. citriodora extracts before their direct incorporation into the polymer films. At this point, the potent antimicrobial properties of the phenol compounds and bioactive components demonstrated an antibacterial activity that was particularly noticeable at a hexane resolution. Different morphological characteristics were seen on films made from these solvent extracts, such as Cs/PVP-AE, Cs/PVP-EAE, and Cs/PVP-HE, when scanning electron microscopy was used. Numerous other outcomes of all the interactions between the extract particles and the film were shown by the pores defined by the Cs/PVP film's porous nature. The addition of the extracts, either alone or in combination, greatly enhanced the Cs/NC/PVP films' mechanical characteristics. It has also been shown that adding plant extracts greatly increased the antibacterial activity of these films. These findings reveal that Cs/PVP films loaded with extract may be utilized as more environmentally acceptable substitutes for possible food packaging application by increasing shelf life of food products.


Asunto(s)
Antibacterianos , Quitosano , Eucalyptus , Extractos Vegetales , Povidona , Quitosano/química , Eucalyptus/química , Antibacterianos/farmacología , Antibacterianos/química , Povidona/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Embalaje de Alimentos , Pruebas de Sensibilidad Microbiana
8.
Sci Rep ; 14(1): 5789, 2024 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-38461344

RESUMEN

The production of surface compounds coated with active substances has gained significant attention in recent years. This study investigated the physical, mechanical, antioxidant, and antimicrobial properties of a composite made of starch and zinc oxide nanoparticles (ZnO NPs) containing various concentrations of Ferula gummosa essential oil (0.5%, 1%, and 1.5%). The addition of ZnO NPs improved the thickness, mechanical and microbial properties, and reduced the water vapor permeability of the starch active film. The addition of F. gummosa essential oil to the starch nanocomposite decreased the water vapor permeability from 6.25 to 5.63 g mm-2 d-1 kPa-1, but this decrease was significant only at the concentration of 1.5% of essential oils (p < 0.05). Adding 1.5% of F. gummosa essential oil to starch nanocomposite led to a decrease in Tensile Strength value, while an increase in Elongation at Break values was observed. The results of the antimicrobial activity of the nanocomposite revealed that the pure starch film did not show any lack of growth zone. The addition of ZnO NPs to the starch matrix resulted in antimicrobial activity on both studied bacteria (Staphylococcus aureus and Escherichia coli). The highest antimicrobial activity was observed in the starch/ZnO NPs film containing 1.5% essential oil with an inhibition zone of 340 mm2 on S. aureus. Antioxidant activity increased significantly with increasing concentration of F. gummosa essential oil (P < 0.05). The film containing 1.5% essential oil had the highest (50.5%) antioxidant activity. Coating also improved the chemical characteristics of fish fillet. In conclusion, the starch nanocomposite containing ZnO NPs and F. gummosa essential oil has the potential to be used in the aquatic packaging industry.


Asunto(s)
Antiinfecciosos , Ferula , Nanopartículas , Aceites Volátiles , Óxido de Zinc , Animales , Aceites Volátiles/farmacología , Aceites Volátiles/química , Óxido de Zinc/farmacología , Óxido de Zinc/química , Antioxidantes/farmacología , Antioxidantes/química , Staphylococcus aureus , Vapor , Antiinfecciosos/farmacología , Antiinfecciosos/química , Almidón/química , Escherichia coli , Nanopartículas/química
9.
Int J Biol Macromol ; 264(Pt 1): 130483, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38430999

RESUMEN

To investigate the efficacy of sodium alginate-konjac glucomannan (SA-KGM) films with anthocyanins (LRA) and tea polyphenols (TP) in meat, beef and grass carp were selected as representative meat products for preservation and freshness monitoring experiments at 4 °C. Concurrently, storage experiments of the films were conducted in this controlled environment. The results of the storage experiment showed that the films delayed meat spoilage by 2-4 days, nearly doubling the preservation time compared to the blank control. Additionally, the film exhibited significant capability to monitor the spoilage process of beef and grass carp. It was revealed by curve fitting analysis that there was a significant correlation between the color change of the film and the spoilage index of the meat. Throughout the storage experiment with the film, it was observed that moisture significantly influenced the microstructure and bonding situation of the films, thereby impacting their mechanical and barrier properties. However, the films were still able to maintain satisfactory physicochemical properties in general. The above findings were crucial in guiding the promotion of the film within the food preservation industry.


Asunto(s)
Alginatos , Lycium , Mananos , Animales , Bovinos , Alginatos/química , Antocianinas/química , Polifenoles/química , Té/química , Embalaje de Alimentos
10.
Int J Biol Macromol ; 265(Pt 1): 130765, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38462119

RESUMEN

Essential oils (EOs) are liquid extracts derived from various parts of herbal or medicinal plants. They are widely accepted in food packaging due to their bioactive components, which exhibit remarkable antioxidant and antimicrobial properties against various pathogenic and food spoilage microorganisms. However, the functional efficacy of EOs is hindered by the high volatility of their bioactive compounds, leading to rapid release. Combining biopolymers with EOs forms a complex network within the polymeric matrix, reducing the volatility of EOs, controlling their release, and enhancing thermal and mechanical stability, favoring their application in food packaging or processing industries. This study presents a comprehensive overview of techniques used to encapsulate EOs, the natural polymers employed to load EOs, and the functional properties of EOs-loaded biopolymeric particles, along with their potential antioxidant and antimicrobial benefits. Additionally, a thorough discussion is provided on the widespread application of EOs-loaded biopolymers in the food industries. However, research on their utilization in confectionery processing, such as biscuits, chocolates, and others, remains limited. Further studies can be conducted to explore and expand the applications of EOs-loaded biopolymeric particles in food processing industries.


Asunto(s)
Antiinfecciosos , Aceites Volátiles , Aceites Volátiles/farmacología , Antioxidantes/farmacología , Industria de Procesamiento de Alimentos , Embalaje de Alimentos/métodos , Biopolímeros , Polímeros , Industria de Alimentos
11.
Int J Biol Macromol ; 265(Pt 1): 130949, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38508545

RESUMEN

This study addresses the growing interest in bio-based active food packaging by infusing Lepidium sativum (Garden cress) seeds extract (GRCE) into sodium alginate (SALG) films at varying concentrations (1, 3, and 5 %). The GRCE extract revealed six phenolic compounds, with gallic and chlorogenic acids being prominent, showcasing substantial total phenolic content (TPC) of 139.36 µg GAE/mg and total flavonoid content (TFC) of 26.46 µg RE/mg. The integration into SALG films significantly increased TPC, reaching 30.73 mg GAE/g in the film with 5 % GRCE. This enhancement extended to DPPH and ABTS activities, with notable rises to 66.47 and 70.12 %, respectively. Physical properties, including tensile strength, thickness, solubility, and moisture content, were positively affected. A reduction in water vapor permeability (WVP) was reported in the film enriched with 5 % GRCE (1.389 × 10-10 g H2O/m s p.a.). FT-IR analysis revealed bands indicating GRCE's physical interaction with the SALG matrix, with thermal stability of the films decreasing upon GRCE integration. SALG/GRCE5 effectively lowered the peroxide value (PV) of sunflower oil after four weeks at 50 °C compared to the control, with direct film-oil contact enhancing this reduction. Similar trends were observed in the K232 and K270 values.


Asunto(s)
Alginatos , Lepidium sativum , Alginatos/química , Espectroscopía Infrarroja por Transformada de Fourier , Embalaje de Alimentos/métodos , Fenoles , Extractos Vegetales/química , Estrés Oxidativo
12.
Wound Repair Regen ; 32(3): 279-291, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38353052

RESUMEN

Pressure ulcer (PU) is a worldwide problem that is difficult to address because of the related inflammatory response, local hypoxia, and repeated ischaemia/reperfusion, causing great suffering and financial burden to patients. Traditional Chinese medicine turtle plate powder can treat skin trauma, but its composition is complex and inconvenient to use. Here, we combined cholesterol myristate (S8) with berberine (BBR), with anti-inflammatory and antibacterial effects, as a drug and used hydroxypropyl methylcellulose and polyvinylpyrrolidone K30 as carriers to construct a novel film-forming polymeric solution (S8 + BBR FFPS), comprehensively study its reparative effect on PU and explore the potential mechanism in rat PU models. The results showed that S8 + BBR FFPS inhibits excessive inflammatory response, promotes re-epithelialization, and promotes hair follicle growth during the healing process of PU, which may be related to the activation of the Wnt/ß-catenin signalling pathway by S8 + BBR FFPS to mediate hair follicle stem cell proliferation and maintain skin homeostasis. Therefore, S8 + BBR FFPS may be a potential candidate for the treatment of chronic skin injury, and its association with the Wnt/ß-catenin signalling pathway may provide new ideas to guide the design of biomaterial-based wound dressings for chronic wound repair.


Asunto(s)
Berberina , Modelos Animales de Enfermedad , Úlcera por Presión , Ratas Sprague-Dawley , Vía de Señalización Wnt , Cicatrización de Heridas , Animales , Úlcera por Presión/tratamiento farmacológico , Berberina/farmacología , Berberina/uso terapéutico , Ratas , Cicatrización de Heridas/efectos de los fármacos , Vía de Señalización Wnt/efectos de los fármacos , Masculino , Polímeros/farmacología , Proliferación Celular/efectos de los fármacos
13.
Heliyon ; 10(4): e26323, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38404824

RESUMEN

The integration of photovoltaic technologies within the agricultural framework, known as agrivoltaics, emerges as a promising and sustainable solution to meet the growing global demands for energy and food production. This innovative technology enables the simultaneous utilization of sunlight for both photovoltaics (PV) and photosynthesis. A key challenge in agrivoltaic research involves identifying technologies applicable to a wide range of plant species and diverse geographic regions. To address this challenge, we adopt a multi-experimental and multi-species approach to assess the viability of semi-transparent, spectrally selective thin-film silicon PV technology. Our findings demonstrate compatibility with crop production in controlled environments for both plants and algae. Notably, selective thin-film PV exhibits the potential to enhance crop yields and serves as a photo-protectant. We observe that plant and algal growth increases beneath the selective PV film when supplemented with appropriate diffuse light in the growth environment. Conversely, in situations where light intensity exceeds optimal levels for plant growth, the selective PV film provides a photo-protective effect. These results suggest potential supplementary benefits of employing this technology in regions characterized by excessive light irradiation, where it can contribute to healthy plant growth.

14.
Int J Biol Macromol ; 263(Pt 1): 130288, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38378108

RESUMEN

This work aimed to assess the synergistic antibacterial effects of thyme and oregano essential oils in various ratios (thyme:oregano; 10:0, 8:2, 6:4, 4:6, 2:8, 10:0). We hypothesized that the synergistic combination of thyme and oregano essential oils can be effectively incorporated into sericin/pectin film to enhance its functional properties. Among the combinations tested, the mixture of thyme/oregano essential oil (TOE) at an 8:2 ratio exhibited the most potent synergistic activity against P. aeruginosa and S. aureus, with fractional inhibitory concentration index (FICindex) of 0.9. In this combination, thymol constituting 51.83 % of TOE (8:2), was the predominant component. TOE at an 8:2 ratio was selected to incorporate into sericin/pectin film. Different concentrations of TOE (0.8 %, 1.2 % and 1.6 %) were applied to evaluate their impact on film properties compared to a film without essential oil (control). It was found that increasing TOE concentration (control; 0 %) to 1.6 % reduced film moisture content (from 21.53 % to 16.91 %), decreased yellowness (from 18.24 to 15.92), diminished gloss (from 63.79 to 11.18), lowered swelling index (from 1.24 to 0.98), and reduced tensile strength (from 9.70 to 4.14 MPa). However, the addition of TOE showed higher film total phenolic content (8.59-31.53 mg gallic acid/g dry sample) and increased antioxidant activity (0.99-3.68 µmol Trolox /g dry sample). Moreover, the film with 1.2 % and 1.6 % of thyme/oregano essential oil exhibited inhibitory effects against all tested bacteria. Therefore, the thyme/oregano essential oil combination can provide the desirable physicochemical properties of the sericin/pectin film, as well as its antibacterial and antioxidant activities, making it a promising alternative for food packaging material applications.


Asunto(s)
Aceites Volátiles , Origanum , Aceites de Plantas , Sericinas , Timol , Thymus (Planta) , Aceites Volátiles/farmacología , Aceites Volátiles/química , Origanum/química , Pectinas , Thymus (Planta)/química , Staphylococcus aureus , Antibacterianos/farmacología , Antioxidantes/farmacología
15.
Int J Biol Macromol ; 263(Pt 1): 130297, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38382781

RESUMEN

In this study, we have successfully produced a corn starch-based composite film through the casting method, formulated with clove essential oil nanoemulsion (NCEO) and corn starch. The physical and chemical changes of the composite films were investigated at various concentrations (10 %, 20 % and 40 %) of NCEO. Furthermore, the non-contact preservation effects of the composite films on bread during 15-day storage were also examined in this study. As the concentration of NCEO increased, the composite films presented a gradual thinning, roughening, and yellowing in appearance. Following this, the water content, water vapor permeability rate, and elongation at break of the films decreased, while their hydrophobicity, tensile strength, antioxidant and antimicrobial activity increased accordingly. Through FT-IR, X-ray diffraction and thermal gravimetric analysis, it was demonstrated that NCEO has strong compatibility with corn starch. Additionally, the indices' analysis indicated that utilizing the composite film incorporating 40 % NCEO can significantly boost the shelf life and quality of bread. Moreover, it was revealed that application of the non-contact treatment with composite film could potentially contribute certain preservation effects towards bread. In light of these findings, the composite film with non-contact treatment exhibits potential as an effective, safe, and sustainable preservation technique for grain products.


Asunto(s)
Aceites Volátiles , Syzygium , Aceites Volátiles/farmacología , Aceites Volátiles/química , Aceite de Clavo/farmacología , Aceite de Clavo/química , Almidón/química , Espectroscopía Infrarroja por Transformada de Fourier , Pan , Permeabilidad , Embalaje de Alimentos
16.
Int J Biol Macromol ; 263(Pt 1): 130286, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38382795

RESUMEN

This study evaluated the physicochemical and antioxidant properties of clove essential oil (0, 0.2, 0.4, 0.6, 0.8, 1.0 % v/v) nanoemulsion (CEON) loaded chitosan-based films. With the increasing concentrations of the CEON, the thickness, b* and ΔE values of the films increased significantly (P < 0.05), while L* and light transmission dropped noticeably (P < 0.05). The hydrogen bonds formed between the CEON and chitosan could be demonstrated through Fourier-transform infrared spectra, indicating their good compatibility and intermolecular interactions. Furthermore, the added CEON considerably reduced the crystallinity and resulted in a porous structure of the films, as observed through X-ray diffraction plots and scanning electron microscopy images, respectively. This eventually led to a drop in both tensile strength and moisture content of the films. Moreover, the antioxidant properties were significantly enhanced (P < 0.05) with the increase in the amount of clove essential oil (CEO) due to the encapsulation of CEO by the nanoemulsion. Films containing 0.6 % CEO had higher elongation at break, higher water contact angle, lower water solubility, lower water vapor permeability, and lower oxygen permeability than the other films; therefore, such films are promising for application in meat preservation.


Asunto(s)
Quitosano , Aceites Volátiles , Syzygium , Quitosano/química , Aceites Volátiles/farmacología , Aceite de Clavo/farmacología , Antioxidantes/farmacología , Antioxidantes/química , Syzygium/química , Espectroscopía Infrarroja por Transformada de Fourier , Permeabilidad , Embalaje de Alimentos/métodos , Vapor
17.
Behav Res Ther ; 174: 104495, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38401468

RESUMEN

Imagery Rescripting (ImRs) has proven effective in reducing involuntary emotional memories. However, it is unclear whether and when it may lead to reduced accuracy of voluntary memory. Although previous analogue studies suggest that ImRs does not pose a general risk regarding memory distortion, it can not be ruled out that ImRs could cause memory impairment under certain risk conditions. In our three-day online trauma film study we investigated in a healthy sample (N = 267) whether specific instructions during ImRs as typically provided in clinical practice (i.e., detailed imagery with a sensory focus) increase the risk of memory distortions. Additionally, we examined whether the completeness of the original memory moderates these instruction effects. Contrary to our expectations, a sensory focus during ImRs was associated with higher memory accuracy in a recognition task, independently of the quality of the original memory. These results extend previous findings by suggesting that ImRs does not even impair memory performance when the quality of the original memory is poor and when the production of sensory-rich images is specifically encouraged. Our results question current practices employed to assess witness statement credibility, which are partly based on concerns that trauma-focused interventions like ImRs undermine memory accuracy.


Asunto(s)
Emociones , Imágenes en Psicoterapia , Humanos , Imágenes en Psicoterapia/métodos , Trastornos de la Memoria , Cognición , Reconocimiento en Psicología
18.
Chemosphere ; 352: 141366, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38311037

RESUMEN

The oxidation of pyrite results in the formation of a solid film passivation layer on its surface. This layer effectively hinders the direct interaction between H2O, O2, and the pyrite surface, thereby impeding the oxidation dissolution of pyrite. There are few studies on whether alumina (Al2O3), a common aluminum-containing oxide, affects the formation of a solid film passivation layer on the surface of pyrite and inhibits the oxidation dissolution of pyrite. This research investigates the impact of Al2O3 incorporation on the speciation transformation of S, Fe, and Al on the surface of pyrite during oxygen pyrite process. The oxidation of pyrite followed the "polysulfide-thiosulfate" complex oxidation pathway. When <1.5 g/L Al2O3 was introduced, it increase pyrite oxidation, whereas ≥1.5 g/L Al2O3 prevented pyrite oxidation. The process of Al2O3 dissolution results in the consumption of H+ and the subsequent release of Al3+. This, in turn, facilitates the hydrolysis of Fe3+ and Al3+ to generate a secondary mineral layer on the pyrite surface. As a result of the accumulation of S promotes the formation of polysulfide chemical (FeSn) or iron deficiency sulfide (Fe1-xS), resulting in the formation of a solid film passivation layer composed of sulfur film and secondary mineral layer. The results demonstrated that Al2O3 can promote the formation of a solid film passivation layer on the surface of pyrite, which has significant implications for controlling the oxidation dissolution process of pyrite and offers a new perspective for the source control of acid mine drainage.


Asunto(s)
Óxido de Aluminio , Hierro , Minerales , Sulfuros/metabolismo , Oxidación-Reducción , Estrés Oxidativo
19.
Food Chem ; 443: 138506, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38306905

RESUMEN

Researchers are addressing environmental concerns related to petroleum-based plastic packaging by exploring biopolymers from natural sources, chemical synthesis, and microbial fermentation. Despite the potential of individual biopolymers, they often exhibit limitations like low water resistance and poor mechanical properties. Blending polymers emerges as a promising strategy to overcome these challenges, creating films with enhanced performance. This review focuses on recent advancements in chitosan/polyvinyl alcohol (PVA) blend food packaging films. It covers molecular structure, properties, strategies for performance improvement, and applications in food preservation. The blend's excellent compatibility and intermolecular interactions make it a promising candidate for biodegradable films. Future research should explore large-scale thermoplastic technologies and investigate the incorporation of additives like natural extracts and nanoparticles to enhance film properties. Chitosan/PVA blend films offer a sustainable alternative to petroleum-based plastic packaging, with potential applications in practical food preservation.


Asunto(s)
Quitosano , Petróleo , Alcohol Polivinílico/química , Quitosano/química , Embalaje de Alimentos , Biopolímeros/química
20.
Food Chem ; 445: 138721, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38359571

RESUMEN

The aim of this study was to modify carboxymethyl cellulose (CMC) films with onion peel extract (OPE) (0-2 g), onion peel powder (OPP) (0-2 g) and boron nitride nanoparticles (BN) (0-100 mg). 17 different CMC/OPE/OPP/BN films were provided and the physicochemical properties of films were studied. The release of active compounds of the composite film was investigated over time. The obtained results showed that OPE, OPP and BN increased the physical resistance and flexibility of the films. The percentage of moisture and solubility of the films decreased with the increase of OPE, OPP and BN. By adding BN, OPE and OPP, the structure of the film became stronger and the permeability to water vapor decreased. Addition of OPE and OPP significantly increased the antioxidant property of the film. In general, it can be said that the antioxidant substances of the onion peel are protected inside the film by preparing a CMC/OPE/OPP/BN film, which, in addition to stabilizing the antioxidants, can play an effective role in the controlled release of these antioxidant substances.


Asunto(s)
Antioxidantes , Compuestos de Boro , Cebollas , Antioxidantes/química , Cebollas/química , Carboximetilcelulosa de Sodio/química , Polvos , Embalaje de Alimentos
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