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The contamination of environmental sites due to the presence of persistent species represents an important issue to be tackled. In particular, the presence of high levels of metals in soil and surface water is more frequent. One of the metals that sometimes exceeds the permissible limit set by regulatory authorities is copper. For instance, copper-based fungicides are widely used in viticulture. However, copper ions remain in soil and can enter the food chain, posing threats to human health and environmental safety. Although the rapid detection of copper ions using portable sensors is effective in enhancing early warning, it sometimes solves only half of the problem as remediation is not considered. In this paper, we present a novel integrated/portable approach that merges the remediation and sensing of metals by proposing a remediate-and-sense concept. In order to realize this concept, alginate beads were coupled with printed electrochemical strips for on-site copper detection. Within the same architecture, alginate beads were used to remove copper ions from the soil, and printed electrochemical strips were used to evaluate the efficacy of remediation at the point of need. The concept was applied towards soil containing copper ions at the parts per billion level; with few alginate beads and in the absence of additional species, copper ions were quantitatively removed from the matrix; and 3D printing allowed us to combine the printed strips and spheres within a unique tool. The architecture was optimized and the results were compared to inductively coupled plasma-mass spectrometry (ICP-MS) measurements with a recovery percentage of 90%-110%. It should be noted that this novel portable approach may be applied to other pollutants, opening new possibilities for integrated remediation and sensing.
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In the present work, a comprehensive study was carried out to better understand the molecular characteristics of amylose extracted from sago starch, using butanol as the extraction solvent. The sago derived amylose was compared with amylose extracted from corn starch and both characterized through different techniques, i.e. size exclusion chromatography, X-ray diffraction (XRD), Fourier transform infrared spectroscopy, Raman spectroscopy, Scanning electron microscopy, Atomic force microscopy and Zeta potential measurements. The purity of the amylose extracted from sago and corn was 99.20 % and 93.46 %, respectively. From XRD results, it was revealed that sago amylose had more crystallinity with high thermal stability compared to corn amylose. Based on Raman spectra, single and double helices formed in both extracted amyloses, but due to their intrinsic differences, the intensities associated with these helices varied for sago and corn amylose. Purified amyloses were shown to have two different forms of spherulite morphology: torus and spherical shapes with varying degrees of roughness. Our findings demonstrated that sago starch is a novel and low-cost source for supplying amylose, a promising polymer for different applications.
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Amilosa , Zea mays , Amilosa/química , Zea mays/química , Almidón/química , Difracción de Rayos X , SolventesRESUMEN
Nanocellulose has received immense consideration owing to its valuable inherent traits and impressive physicochemical properties such as biocompatibility, thermal stability, non-toxicity, and tunable surface chemistry. These features have inspired researchers to deploy nanocellulose as nanoscale reinforcement materials for bio-based polymers. A simple yet efficient characterization method is often required to gain insights into the effectiveness of various types of nanocellulose. Despite a decade of continuous research and booming growth in scientific publications, nanocellulose research lacks a measuring tool that can characterize its features with acceptable speed and reliability. Implementing reliable characterization techniques is critical to monitor the specifications of nanocellulose alone or in the final product. Many techniques have been developed aiming to measure the nano-reinforcement mechanisms of nanocellulose in polymer composites. This review gives a full account of the scientific underpinnings of techniques that can characterize the shape and arrangement of nanocellulose. This review aims to deliver consolidated details on the properties and characteristics of nanocellulose in biopolymer composite materials to improve various structural, mechanical, barrier and thermal properties. We also present a comprehensive description of the safety features of nanocellulose before and after being loaded within biopolymeric matrices.
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Celulosa , Nanocompuestos , Celulosa/química , Reproducibilidad de los Resultados , Polímeros/química , Nanocompuestos/química , BiopolímerosRESUMEN
In this work, an egg yolk protein hydrolysate (EYPH) with a high iron-chelating ability (87.32%) was prepared. The fractionation using 60% (v/v) ethanol concentration (E3 fraction) led to the efficiently accumulating the iron-chelating peptides in EYPH. The characterization results showed that iron mainly chelated with carboxyl, amino and phosphate groups of peptides. From E3 fraction, six iron-chelating peptides with MW ranging from 1372.36 to 2937.04 Da were identified and a hypothesized molecular model of DDSSSpSpSpSpSpSVLSK-Fe was simulated. In vitro stability determination showed that E3-Fe chelate owned a good heat, alkalinity and digestion tolerance, but a relatively bad acid tolerance. Finally, iron transport analysis showed that iron in the E3-Fe would be absorbed in caco-2 cell membrane more effectively than that of iron salts, indicating that it was possible to apply the E3-Fe complex as iron supplements.
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Essential oils (EOs) have been proved as natural food preservatives because of their effective and wide-spectrum antimicrobial activity. They have been extensively explored for potential applications in food industry, and substantial progresses have been achieved. However well EOs perform in antibacterial tests in vitro, it has generally been found that a higher level of EOs is needed to achieve the same effect in foods. Nevertheless, this unsimilar effect has not been clearly quantified and elaborated, as well as the underlying mechanisms. This review highlights the influence of intrinsic properties (e.g., oils and fats, carbohydrates, proteins, pH, physical structure, water, and salt) and extrinsic factors (e.g., temperature, bacteria characteristics, and packaging in vacuum/gas/air) of food matrix systems on EOs action. Controversy findings and possible mechanism hypotheses are also systematically discussed. Furthermore, the organoleptic aspects of EOs in foods and promising strategies to address this hurdle are reviewed. Finally, some considerations about the EOs safety are presented, as well as the future trends and research prospects of EOs applications in foods. The present review aims to fill the evidenced gap, providing a comprehensive overview about the influence of the intrinsic and extrinsic factors of food matrix systems to efficiently orientate EOs applications.
Both intrinsic properties and extrinsic factors of food matrix affect the EOs action.EOs influence on the food organoleptic aspects were reviewed.Promising strategies for overcoming the organoleptic aspects of EOs were listed.Future research prospects are outlined to accelerate EOs application in foods.
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The reprocessing of vegetal-waste represents a new research field in order to design novel biomaterials for potential biomedical applications and in food industry. Here we obtained a biomaterial from Lupinus albus L. hull (LH) that was characterized micro-structurally by scanning electron microscopy and for its antimicrobial and scaffolding properties. A good adhesion and proliferation of human mesenchymal stem cells (hMSCs) seeded on LH scaffold were observed. Thanks to its high content of cellulose and beneficial phytochemical substances, LH and its derivatives can represent an available source for fabrication of biocompatible and bioactive scaffolds. Therefore, a reprocessing protocol of LH was optimized for producing a new LH bioplastic named BPLH. This new biomaterial was characterized by chemico-physical analyses. The water uptake, degradability and antimicrobial properties of BPLH were evaluated, as well as the mechanical properties. A good adhesion and proliferation of both fibroblasts and hMSCs on BPLH were observed over 2 weeks, and immunofluorescence analysis of hMSCs after 3 weeks indicates an initial commitment toward muscle differentiation. Our work represents a new approach toward the recovery and valorization of the vegetal waste showing the remarkable properties of LH and BPLH as cellular waste-based scaffold with potential applications in cell-based food field as well as in medicine for topical patches in wound healing and bedsores treatment.
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Lupinus , Células Madre Mesenquimatosas , Humanos , Materiales Biocompatibles/química , Andamios del Tejido/química , Verduras , Diferenciación Celular , Proliferación Celular , Osteogénesis , Ingeniería de Tejidos/métodosRESUMEN
Today, the development of multifunctional and versatile packaging materials based on green ingredients has received a lot of attention from researchers and consumers due to their biodegradability, biocompatibility, sustainability, and renewable nature of biomaterials. These emerging packaging materials in addition to increasing the shelf life of food products (active packaging), informs the consumer about the freshness and spoilage of the product in real-time (smart packaging). The limitations reported for biopolymers-based packaging, such as hydrophilicity and poor mechanical resistance, can be modified and improved by combining biopolymers with various materials including nanomaterials, cross-linkers, bioactive compounds, and other polymers. Consequently, the use of innovative, high performance, and green bio-nanocomposites reveal a promising opportunity to replace conventional non-biodegradable petroleum-based plastics. Likewise, interest in making polymeric bio-nanocomposites for active and smart packaging purposes has been increased in response to a global request for more effective and safe food packaging systems. There are various factors affecting the quality of bio-nanocomposites, such as biomaterials type, additives like nanoparticles, foods type, storage conditions, and the approaches for their preparation. In this review paper, we aimed to discuss the main challenges of the techniques commonly employed to prepare polymeric bio-nanocomposites, including casting, melt mixing (extrusion), electrospinning, and polymerization techniques. The casting has captured scientists' interest more than other techniques, due to the easy handling. The extrusion methods showed a more industrial approach than other techniques in this field. The electrospinning process has attracted a lot of interest due to the production of fibrous membranes, able to encapsulate and stabilize bioactive molecules. The polymerization technique shows less interest amongst scientists due to its complicated conditions, its reaction-based process and the use of toxic and not green reactants and solvents. In conclusion, all techniques should be optimized based on relevant specific parameters to obtain bio-nanocomposites with notable mechanical behaviors, barrier and permeability properties, contact angle/wettability, uniform structures, low cost of production, environmental-friendly nature, migration and penetration, and biodegradability features.
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Embalaje de Alimentos , Nanocompuestos , Embalaje de Alimentos/métodos , Nanocompuestos/química , Biopolímeros/química , Materiales Biocompatibles , PolímerosRESUMEN
Caffeine, as one of the most consumed bioactive compounds globally, has gained considerable attention during the last years. Considering the bitter taste and adverse effects of high levels of caffeine consumption, it is crucial to apply a strategy for masking the caffeine's bitter taste and facilitating its programmable deliverance within a long time. Other operational parameters such as food processing parameters, exposure to sunlight and oxygen, and gastrointestinal digestion could also degrade the phenolic compounds in general and caffeine in special. To overcome these challenges, various nano/micro-platforms have been fabricated, including lipid-based (e.g., nanoliposomal vehicles; nanoemulsions, double emulsions, Pickering emulsions; microemulsions; niosomal vehicles; solid lipid nanoparticles and nanostructured lipid carriers), as well as biopolymeric (e.g., nanoparticles; hydrogels, organogels, oleogels; nanofibers and nanotubes; protein-polysaccharide nanocomplexes, conjugates; cyclodextrin inclusion complexes) and inorganic (e.g., gold and silica nanoparticles) nano/micro-structures. In this review, the findings on various caffeine-loaded nano/micro-carriers and their potential applications in functional food products/supplements will be discussed. Also, the controlled release and bioavailability of encapsulated caffeine will be given, and finally, the toxicity and safety of encapsulated caffeine will be presented.
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Biopolymers are important due to their exceptional functional and barrier properties and also their non-toxicity and eco-friendly nature for various food, biomedical, and pharmaceutical applications. However, biopolymers usually need reinforcement strategies to address their poor mechanical, thermal, and physical properties as well as processability aspects. Several natural nanoparticles have been proposed as reinforcing agents for biopolymeric food packaging materials. Among them, zein nanoparticles (ZNPs) have attracted a lot of interest, being an environmentally friendly material. The purpose of the present review paper is to provide a comprehensive overview of the ZNPs-loaded nanocomposites for food packaging applications, starting from the synthesis, characteristics and properties of ZNPs, to the physicochemical properties of the ZNPs-loaded nanocomposites, in terms of morphology, permeability, solubility, optical features, hydrophobic/hydrophilic behavior, structural characteristics, thermal features, and mechanical attributes. Finally, at the end of this review, some considerations about the safety issues and gastrointestinal fate of ZNPs, as well as the use of ZNPs-based nanocomposites as food packaging, are reported, taking into account that, despite the enormous benefits, nanotechnology also presents some risks associated to the use of nanometric materials.
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The aim of this study is to bio-monitor the levels of 16 polycyclic aromatic hydrocarbons (PAHs) in cold smoked beef and sausages. The ability of probiotics to remove PAHs was also investigated as function of the cell viability (viable, non-viable and acid-treated cells), bacterial counts (107, 108, and 109 CFU/mL), pH (3, 5, and 7), and incubation time (6, 12, and 24 h). The results indicated a significant difference (p < 0.05) among the analyzed sausages and beef samples for the PAHs concentration. Non-viable probiotics achieved the highest PAHs reduction rates. Limosilactobacillus fermentum EMCC 1346 presented the lowest binding activity value (i.e. 41.10-56.80 %) for all PAHs, followed by Lacticaseibacillus rhamnosus EMCC 1105 with binding percentage of 50.40-65.80 %. On the other hand, the highest removal for all PAHs was achieved by Lactobacillus bulgaricus EMCC 1102 with binding rate of 60.50-76.80 %, at 109 CFU/mL, pH 7, after incubation for 24 h. The fortified sausages results revealed that L. bulgaricus EMCC 1102 cultures exhibited the maximum and significant reduction (p < 0.05) of PAHs with values of 44.71 µg/kg for the center part, compared to control non treated sausages (82.65 µg/kg). Regarding the sensorial profile, treated samples with probiotics led to a preference from the panelists, compared to control. Consequently, the results confirm that fermented probiotic suspension is a feasible future strategy to control PAHs levels in cold smoked meat stuffs.
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Limosilactobacillus fermentum , Productos de la Carne , Hidrocarburos Policíclicos Aromáticos , Probióticos , Animales , Bovinos , Productos de la Carne/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Probióticos/metabolismo , HumoRESUMEN
Viral infections are a major cause of severe, fatal diseases worldwide. Recently, these infections have increased due to demanding contextual circumstances, such as environmental changes, increased migration of people and product distribution, rapid demographic changes, and outbreaks of novel viruses, including the COVID-19 outbreak. Internal variables that influence viral immunity have received attention along with these external causes to avert such novel viral outbreaks. The gastrointestinal microbiome (GIM), particularly the present probiotics, plays a vital role in the host immune system by mediating host protective immunity and acting as an immune regulator. Bacteriocins possess numerous health benefits and exhibit antagonistic activity against enteric pathogens and immunobiotics, thereby inhibiting viral infections. Moreover, disrupting the homeostasis of the GIM/host immune system negatively affects viral immunity. The interactions between bacteriocins and infectious viruses, particularly in COVID-19, through improved host immunity and physiology are complex and have not yet been studied, although several studies have proven that bacteriocins influence the outcomes of viral infections. However, the complex transmission to the affected sites and siRNA defense against nuclease digestion lead to challenging clinical trials. Additionally, bacteriocins are well known for their biofunctional properties and underlying mechanisms in the treatment of bacterial and fungal infections. However, few studies have shown the role of probiotics-derived bacteriocin against viral infections. Thus, based on the results of the previous studies, this review lays out a road map for future studies on bacteriocins for treating viral infections.
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OBJECTIVES: Open surgery is a reliable choice for congenital subglottic stenosis, that represents the third most common congenital anomaly of the larynx. One of the procedures performed is anterior laryngotracheal reconstruction (LTR) with anterior rib graft. The objective of this preliminary study was to evaluate the potential of 3D printing technology for the realization of laryngo-tracheal scaffold in Polycaprolactone (PCL) implanted in vivo in ovine animal model. METHODS: A 3D computer model of a laryngeal graft and a tracheal graft was designed and printed with PCL through 3D additive manufacturing technology. The scaffolds were seeded with autologous mesenchymal stem cells and cultured in vitro for up to 14 days. Anterior graft LTR with 3D printed scaffolds was performed on 5 sheep. The animals underwent endoscopic examinations at the first, 3rd, 6th, and 12th weeks after surgery and before sacrifice. The integration of the material was evaluated by the pathologist. RESULTS: Two animals showed a favourable postoperative course and were sacrificed at 6 months postoperatively. In these cases, we observed endoscopically a complete integration of the cellularized PCL scaffold into the peri-implant tissues, and the pathologist found the growth of respiratory epithelium on the scaffold's inner surface. Other two animals showed a difficult post-operative recovery characterized by respiratory distress resulting in early sacrifice on postoperative days 31 and 33. In these animals we found a poor integration of the grafts into the tracheal structure, and a better integration of the laryngeal scaffold. The last animal developed a wound abscess and was sacrificed 80 days after surgery. We observed, in this case, a poor scaffold integration and an acute inflammatory reaction. CONCLUSIONS: From the preliminary data obtained we found that the excessive stiffness of the material, along with the anatomical features of the sheep, is a major limitation of this study. It will be necessary in the future to create a new biocompatible, more flexible and elastic graft, to achieve greater integration into surrounding tissues. Bioconstructed grafts could simplify surgery for the treatment of laryngo-tracheal stenosis, particularly in the treatment of long tracheal stenoses, which have, at the moment, very complex surgical options. LEVEL OF EVIDENCE: NA.
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Bioimpresión , Laringoestenosis , Procedimientos de Cirugía Plástica , Estenosis Traqueal , Animales , Laringoestenosis/cirugía , Proyectos Piloto , Impresión Tridimensional , Procedimientos de Cirugía Plástica/métodos , Ovinos , Andamios del Tejido , Tráquea/cirugía , Estenosis Traqueal/cirugíaRESUMEN
The beany flavor adversely influences consumer acceptance of soymilk (SM) products. Thus, in this work, the co-fermentation of isolated new yeasts (Kluyveromyces marxianus SP-1, Candida ethanolica ATW-1, and Pichia amenthionina Y) and Kluyveromyces marxianus K (a commercial yeast) along with an XPL-1 starter (including five strains of lactic acid bacteria (LAB)) was utilized to mend the beany flavor of fermented SM (FSM) beverages. Probiotic count, pH, titratable acidity, syneresis, water holding capacity, rheological characteristics, and sensory attributes were investigated. Furthermore, the free amino acids, nucleotides, and volatile compounds (VCs) were analyzed, also presenting the collected VC data by exploiting a principal component analysis (PCA) and a heatmap with a hierarchical cluster analysis. The co-fermentation with Kluyveromyces marxianus SP-1 and K remarkably enhanced the LAB strain growth and acid production, improving the rheological attributes, whereas that of yeast along with XPL-1 as a mullite starter could reduce the beany odor. PCA chart displayed that higher amounts of alcohols, ketones, acids, and esters that significantly improved the flavor quality of FSM beverages were generated throughout the co-fermentation process. The co-fermentation with Pichia amenthionina Y generated the highest acetoin (36.19%) and diacetyl (2.02%), thus improving the overall acceptance of FSM, as well as the sensory characteristics of FSM beverages with the highest umami, sweet, odorless amino acids, and umami nucleotides, and the lowest content of alcohol and inosine. Taken together, the co-fermentation of Pichia amenthionina Y along with XPL-1 within SM provides novel insights regarding the development of FSM and fermented beverages.
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Kluyveromyces , Lactobacillales , Aminoácidos/metabolismo , Fermentación , Kluyveromyces/metabolismo , Lactobacillales/metabolismo , Nucleótidos/metabolismo , Levaduras/metabolismoRESUMEN
Recently, the research and innovation to produce raw materials from microbial processes has gained much attention due to their economic and environmental impacts. Lactic acid is a very important microbial product due to its wide application in the food, pharmaceutical, cosmetic, and chemical industries. In the current study, poly (L-lactic acid) (PLLA) was produced by the ring opening polymerization (ROP) technique of L-lactic acid recovered from whey fermentation, and was used for the production of nanocomposites films reinforced with chitosan nanoparticles (CNPs) (average diameter ca. 100-200 nm). Three different CNPs concentrations, namely 1, 3, and 5% w/w, were tested, and their influence on the physical, mechanical, thermal, antibacterial and structural attributes of PLLA film was assessed. The results showed that the addition of CNPs up to 3% caused a significant improvement in water vapor permeability, appearance, tensile strength and elongation at break. The antibacterial properties of nanocomposites followed a dose-depended pattern as a result of CNPs addition. Therefore, the best inhibitory effects on Escherichia coli and Staphylococcus aureus was made by the addition of 5% of CNPs and lower dosages slightly affected the growth of pathogens or didn't cause any inhibitory effects (in 1% of CNPs). It can be concluded that the incorporation of CNPs into the PLLA matrix allows to improve the structural, thermal, physical, mechanical and antibacterial properties of the polymer, generating promising systems for food packaging and biomedical applications.
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Goat milk (GM) is an excellent alternative to cow milk and has recently been used in commercial infant formula preparation due to its superior fat composition. Here, the fatty acid (FA) composition, triacylglycerol (TAG) molecular species, thermal behavior and infrared spectra of extracted milk fat from the milk of the two main breeds of dairy goat bred in China (Guanzhong GM (GZG) and Xinong Saanen GM (XSG)) are investigated. Gas chromatography, Fourier-transform infrared spectroscopy, differential scanning calorimetry and ultra-performance convergence chromatography with quadrupole time-of-flight mass spectrometry are applied. The obtained results evidence significant fat compositional differences based on the breed that produced the considered GM. The major FAs in both GM fats were capric (C10:0), myristic (C14:0), palmitic (C16:0), stearic (C18:0) and oleic (C18:1 n-9c). GZG presented a higher content of medium-chain saturated FAs, while XSG had higher unsaturated FAs with higher ratios of L/Ln and n-6/n-3. A total of 339 and 359 TAGs were detected and quantified in GZG and XSG, and the major TAGs were those of m/z 740.6712 (14.10 ± 0.27%) and m/z 684.6094 (10.94 ± 0.02%), respectively. Milk TAGs of GZG and XSG showed 24-54 and 26-54 total acyl carbon numbers with a 0-4 and 0-5 double bond number at 68 and 72 various retention times, respectively. Thermal analysis showed that all GM fat samples melted below normal body temperature. Infrared spectra revealed higher absorption values of GZG milk fat. This study provides valuable information to the dairy industry sector about GM fat produced in China, assessing the appropriateness of Chinese GM fat to be applied in Chinese infant formula.
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Cabras , Leche , Animales , Bovinos , Ácidos Grasos/análisis , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Leche/química , Análisis Espectral , Triglicéridos/análisisRESUMEN
Fruit juices (FJs) are frequently taken owing to their nutritious benefits, appealing flavour, and vibrant colour. The colours of the FJs are critical indicators of the qualitative features that influence the consumer's attention. Although FJs' intrinsic acidity serves as a barrier to bacterial growth, their enzymatic stability remains an issue for their shelf life. Inactivation of enzymes is critical during FJ processing, and selective inactivation is the primary focus of enzyme inactivation. The merchants, on the other hand, want the FJs to stay stable. The most prevalent technique of processing FJ is by conventional heat treatment, which degrades its nutritive value and appearance. The FJ processing industry has undergone a dramatic transformation from thermal treatments to nonthermal treatments (NTTs) during the past two decades to meet the requirements for microbiological and enzymatic stability. The manufacturers want safe and stable FJs, while buyers want high-quality FJs. According to the past investigation, NTTs have the potential to manufacture microbiologically safe and enzymatically stable FJs with low loss of bioactive components. Furthermore, it has been demonstrated that different NTTs combined with or without other NTTs or mild heating as a hurdle technology increase the synergistic effect for microbiological safety and stability of FJs. Concise information about the variables that affect NTTs' action mode has also been addressed. Primary inactivates enzymes by modifying the protein structure and active site conformation. NTTs may increase enzyme activity depending on the nature of the enzyme contained in FJs, the applied pressure, pH, temperature, and treatment period. This is due to the release of membrane-bound enzymes as well as changes in protein structure and active sites that allow substrate interaction. Additionally, the combination of several NTTs as a hurdle technology, as well as temperature and treatment periods, resulted in increased enzyme inactivation in FJs. Therefore, a combination of thermal and non-thermal technologies is suggested to increase the effectiveness of the process as well as preserve the juice quality.
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Manipulación de Alimentos , Jugos de Frutas y Vegetales , Manipulación de Alimentos/métodos , Frutas/química , Calor , Valor Nutritivo , GustoRESUMEN
With an increasing demand for industrial dyes in our daily lives, water conditions have become worse. Recently, the removal of such environmentally hazardous pollutants from wastewaters through photocatalytic degradation has been drawing increased attention. Three mesoporous nanophases of BiFeVOx.y as (Bi2FeIIIV1-yO5.5-y) visible light photocatalysts were synthesized in this study using ethylene glycol-citrate sol-gel synthesis combined with microwave- assisted calcination. X-ray diffraction (XRD), differential thermal analysis (DTA), FTIR spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy coupled with energy dispersive X-ray spectrometry (SEM-EDS), nitrogen adsorption-desorption isotherms, and UV-Vis diffuse reflectance spectrophotometry (UV-Vis/DRS) were used to characterize the BiFeVOx.y photocatalysts. The visible light-induced photocatalytic activities of the BiFeVOx.y phases were evaluated by the degradation of methylene blue (MB) dye in aqueous solution at pH ~10.0. The results of this study show that the combination of doping strategy with the utilization of advanced synthesis methods plays an important role in improving the structure and surface properties of BiFeVOx.y phases, and thereby enhancing their adsorption and photocatalytic efficiencies. The synthesized mesoporous tetragonal γ-BiFeVOx.y nanophase has been proven to be a potential visible-light photocatalyst for the degradation of organic dyes.
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The incorporation of antibiotics and bioactive compounds into non-toxic nanoparticles has been popularly used to produce effective antimicrobial nanocarriers against foodborne pathogens. These systems can protect antimicrobials against harsh environments, control their release, and increase their antimicrobial activities; however, their functions can be decreased by some major barriers. Intracellular localization of bacteria protects them from the host immune system and antimicrobial agents. Also, bacteria can cause constant infection by nestling in professional phagocytic cells. In the last years, surface functionalization of nanocarriers by passive and active modification methods has been applied for their protection against clearance from the blood, increasing both circulation time and uptake by target cells. For achieving this objective, different functional agents such as specifically targeted peptides internalize ligands, saccharide ligands, or even therapeutic molecules (e.g., antibodies or enzymes) are used. In this review, techniques for functionalizing the surface of antimicrobial-loaded nanocarriers have been described. This article offers a comprehensive review of the potential of functional nanoparticles to increase the performance of antimicrobials against foodborne pathogens through targeting delivery.
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Antiinfecciosos , Nanopartículas , Antibacterianos/química , Antibacterianos/farmacología , Antiinfecciosos/química , Antiinfecciosos/farmacología , Bacterias , Portadores de Fármacos/química , Nanopartículas/químicaRESUMEN
This study aimed to develop a plasticized starch (PS) based film loaded with chitosan nanoparticles (CNPs, 1, 2, 3, and 4%) as a reinforcing and antibacterial agent. We examined the morphology, biodegradability, mechanical, thermo-mechanical, and barrier properties of the PS/CNPs films. The antimicrobial activity against both Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria was investigated by colony forming unit (CFU) and disc diffusion methods. A dense structure was obtained for all PS/CNPs films and, thus, their complete biodegradation occurred in more days than neat PS. The increase in the CNPs percentage led to improved mechanical behaviour and barrier properties. PS-CNPs composite films revealed inhibition zones against both E. coli and S. aureus, with the 100% reduction in CFU against S. aureus. The current study exhibited that PS-CNPs films were more effective in inhibiting bacteria growth than neat PS film, confirming the composite films potential application as antimicrobial food packaging.
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Antiinfecciosos/farmacología , Plásticos Biodegradables/farmacología , Quitosano/farmacología , Almidón/química , Antiinfecciosos/síntesis química , Antiinfecciosos/química , Plásticos Biodegradables/síntesis química , Plásticos Biodegradables/química , Quitosano/síntesis química , Quitosano/química , Pruebas Antimicrobianas de Difusión por Disco , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Embalaje de Alimentos , Nanocompuestos , Tamaño de la Partícula , Permeabilidad , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrolloRESUMEN
Chitosan is mainly derived from seafood by-products and the thereof chitosan nanoparticles (CNPs) are known as nontoxic, biocompatible, biodegradable and functionalized nanostructures. CNPs, as green fillers, showed an appropriate potential in reinforcement of various biodegradable composites for food packaging and biomedical applications. After evaluation of different fabrication approaches and characterization techniques of CNPs, the changes in physical, mechanical, thermal, structural, morphological, and antimicrobial attributes of nanobiocomposites as a result of CNPs addition are discussed. The influence of bioactive loaded-CNPs and hybrid CNPs with metal nanoparticles, graphene, and montmorillonite in nanocomposites is also presented. Finally, the safety aspects of CNPs-loaded structures are highlighted to evaluate their implementation in food packaging and biomedical systems. It can be concluded that regardless of a few drawbacks, CNPs are promising nanomaterials to improve various operational, structural and antimicrobial properties of biocomposites for various applications in food packaging, delivery systems and biomedical uses.