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1.
Int J Biol Macromol ; 273(Pt 2): 132969, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38857733

RESUMO

Lactoferrin (LAC) is an iron-binding glycoprotein found in mammalian secretion, such as milk and colostrum, which has several advantageous biological characteristics, such as antioxidant and antimicrobial activity, intestinal iron absorption and regulation, growth factor activity, and immune response. LAC is an active GRAS food ingredient and can be included in the food packaging/film matrix in both free and encapsulated forms to increase the microbial, mechanical, barrier, and thermal properties of biopolymer films. Additionally, LAC-containing films maintain the quality of fresh food and extend the shelf life of food products. This paper primarily focuses on examining how LAC affects the antimicrobial, antioxidant, physical, mechanical, thermal, and optical properties of packaging films. Moreover, the paper explains the attributes of films incorporating LAC within different matrices, exploring the interaction between LAC and polymers. The potential of LAC-enhanced food packaging technologies is highlighted, showcasing their promising applications in sustainable food packaging.


Assuntos
Embalagem de Alimentos , Lactoferrina , Embalagem de Alimentos/métodos , Lactoferrina/química , Antioxidantes/química , Antioxidantes/farmacologia , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Humanos
2.
Int J Biol Macromol ; 259(Pt 2): 129182, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176499

RESUMO

Increasing demand for high-quality fresh fruits and vegetables has led to the development of innovative active packaging materials that exhibit controlled release of antimicrobial/antioxidant agents. In this study, composite biopolymer films consisting of methylcellulose (MC) and chitosan nanofibers (ChNF) were fabricated, which contained lactoferrin (LAC)-loaded silver-metal organic framework (Ag-MOF) nanoparticles. The results indicated that the nanoparticles were uniformly distributed throughout the biopolymer films, which led to improvements in tensile strength (56.1 ± 3.2 MPa), thermal stability, water solubility, swelling index, water vapor barrier properties (from 2.2 ± 2.1 to 1.9 ± 1.9 × 10-11 g. m/m2. s. Pa), and UV-shielding effects. The Ag-MOF-LAC2% films also exhibited strong and long-lasting antibacterial activity against E. coli (19.8 ± 5.2 mm) and S. aureus (20.1 ± 3.2 mm), which was attributed to the slow release of antimicrobial LAC from the films. The composite films were shown to maintain the fresh appearance of apples for at least seven days, which was attributed to their antimicrobial and antioxidant activities. Consequently, these composite films have the potential in the assembly of innovative active packaging materials for protecting fresh fruits and vegetables. However, further work is required to ensure their safety and economic viability.


Assuntos
Anti-Infecciosos , Quitosana , Malus , Nanofibras , Nanopartículas , Metilcelulose , Antioxidantes/farmacologia , Lactoferrina , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Biopolímeros , Embalagem de Alimentos/métodos
3.
Food Chem X ; 20: 100883, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38144784

RESUMO

As tetracycline antibiotics were used in the poultry sector, their residue in edible animal products may adversely affect food safety and human health. The development of selective and sensitive tetracycline sensors has garnered a lot of interest due to the complexity of food samples. Therefore, a fluorescent sensing probe based on chromium(III)-metal-organic framework was developed for the rapid detection of tetracycline. After the addition of tetracycline, blue emission at λem 410 nm was effectively quenched by the interaction between TC and Cr(III)-metal-organic framework material. Under optimized conditions (sensor concentration: 30 mg/L and pH: 10.0), the sensing probe showed a fast response time (1 min), and low detection limit (0.78 ng/mL) with a linear range (5-45 ng/mL). Interestingly, the Cr(III)-metal-organic framework was successfully applied to quantity tetracycline residue in chicken meat and egg samples with recoveries of 95.17-06.93%. To deduce, our work can provide a new strategy for the direct detection of tetracycline in food samples.

4.
Heliyon ; 9(11): e20890, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37928024

RESUMO

The health-care industry is in a state of constant flux, with new challenges and opportunities emerging regularly. Hospitals, as the cornerstone of health-care delivery, must adapt and embrace change to provide optimal patient care. One crucial aspect that plays a significant role in the success of hospitals is sustainable learning. Sustainable learning refers to acquiring knowledge, skills, and competencies that enable health-care professionals to adapt to changes, implement best practices, and deliver high-quality care. Sustainable learning, a concept gaining prominence, emphasizes the ability of hospitals to learn from experiences and adapt to changing circumstances while maintaining quality health-care delivery. This article aims to investigate the role of hospital capabilities in sustainable learning and explore how hospitals can foster an environment that promotes continuous learning and development. Another goal of the paper is to test the relationships between cultural capabilities, structural capabilities, knowledge management capabilities, Information Technology (IT) infrastructure, top management support, application capabilities, and sustainable learning. The Partial Least-Squares (PLS) algorithm was performed using SmartPLS 3.0 to attain this goal. The results successfully support the study goals. This study verified that cultural capability, structural capabilities, knowledge management capabilities, IT infrastructure, top management support, and application capabilities positively affected sustainable learning. This investigation contributes to hospital, management, and education research by developing an integrated paradigm for sustainable learning. In conclusion, the new conceptual model presented here provides a robust framework for investigating the role of hospital capabilities in sustainable learning. By understanding and improving their capabilities, hospitals can not only adapt to change but also thrive in an ever-changing health-care landscape.

5.
Int J Biol Macromol ; 253(Pt 6): 127342, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37838133

RESUMO

The effect of zinc oxide nanoparticles (ZnONPs) on various properties of basil seed mucilage (a heteropolysaccharide)-polyvinyl alcohol (BSM-PVA) films was investigated. Increasing concentration of ZnONPs in BSM-PVA films reduced moisture content (from 24.73 to 17.09 %), water solubility (from 36.36 to 27.65 %), water vapor permeability (from 4.66 × 10-7 to 2.55 × 10-7 g·m/m2·Pa·h), oxygen permeability (from 2.96 to 2.13 cm3 µm/m2 d kPa), and elongation at break (from 40.34 to 29.44 %), and increased ultimate tensile strength (from 16.81 to 21.48 MPa). Color and light transmission were affected by ZnONPs concentrations. The lack of formation of new peaks, along with the displacement of peaks, indicated the formation of hydrogen bonds between ZnONPs and the film matrix. Dynamic mechanical-thermal analysis showed that storage modulus and glass transition temperature increased with the concentration of ZnONPs. Scanning electron microscopy images illustrated that the addition of ZnONPs improved film integrity. X-ray diffraction pattern showed that the crystal shape of nanoparticles was preserved in the film matrix. Films containing ZnONPs showed good antibacterial activity against Staphylococcus aureus (reductions ≥ 3 log CFU/cm2) and Escherichia coli (reductions ≥ 4 log CFU/cm2). Films containing ZnONPs also showed a suitable antifungal activity during the storage of wheat bread.


Assuntos
Nanopartículas , Ocimum basilicum , Óxido de Zinco , Álcool de Polivinil/química , Ocimum basilicum/química , Óxido de Zinco/química , Polissacarídeos/análise , Nanopartículas/química , Biopolímeros/análise , Antibacterianos/química , Sementes/química
6.
Anal Biochem ; 681: 115334, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37774996

RESUMO

This work reports the profit of using a MOF compound for developing a sensitive electrochemical sensor to free chlorine detection in an aqueous solution. Co-MOF and FGO composites were synthesized and combined with the carbon paste (CP) to prepare an efficient electrochemical sensor with high sensing ability. The fabricated Co-MOF and FGO composites were characterized by SEM, EDX, FT-IR, and XRD techniques. Meanwhile, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were utilized to assess the electrochemical performance of the Co-MOF-FGO/CP modified electrode. Under the optimized condition, the amperometric detection showed that the reduction current of free chlorine increased linearly with a coefficient determination of 0.995 during its wide concentration range of 0.1-700 ppm. Also the detection limit (LOD) (S/N = 3) was 0.01 ppm. The selectivity of the sensor was tested with possible interferences, and satisfactory results were obtained. The proposed sensor was successfully used to determine the free chlorine in tap water and swimming pool water real samples. The results suggested that this proposed sensor could pave the way for developing the electrochemical sensor of free chlorine in aqueous media with MOFs.

7.
ACS Omega ; 8(35): 31600-31619, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37692216

RESUMO

Catalysts played a crucial role in advancing modern human civilization, from ancient times to the industrial revolution. Due to high cost and limited availability of traditional catalysts, there is a need to develop cost-effective, high-activity, and nonprecious metal-based electrocatalysts. Metal-organic frameworks (MOFs) have emerged as an ideal candidate for heterogeneous catalysis due to their physicochemical properties, hybrid inorganic/organic structures, uncoordinated metal sites, and accessible organic sections. MOFs are high nanoporous crystalline materials that can be used as catalysts to facilitate polymerization reactions. Their chemical and structural diversity make them effective for various reactions compared to traditional catalysts. MOFs have been applied in gas storage and separation, ion-exchange, drug delivery, luminescence, sensing, nanofilters, water purification, and catalysis. The review focuses on MOF-enabled heterogeneous catalysis for value-added compound production, including alcohol oxidation, olefin oligomerization, and polymerization reactions. MOFs offer tunable porosity, high spatial density, and single-crystal XRD control over catalyst properties. In this review, MOFs were focused on reactions of CO2 fixation, CO2 reduction, and photoelectrochemical water splitting. Overall, MOFs have great potential as versatile catalysts for diverse applications in the future.

8.
Mikrochim Acta ; 190(9): 371, 2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37646854

RESUMO

The measurement of food contaminants faces a great challenge owing to the increasing demand for safe food, increasing consumption of fast food, and rapidly changing patterns of human consumption. As different types of contaminants in food products can pose different levels of threat to human health, it is desirable to develop specific and rapid methods for their identification and quantification. During the past few years, metal-organic framework (MOF)-based materials have been extensively explored in the development of food safety sensors. MOFs are porous crystalline materials with tunable composition, dynamic porosity, and facile surface functionalization. The construction of high-performance biosensors for a range of applications (e.g., food safety, environmental monitoring, and biochemical diagnostics) can thus be promoted through the synergistic combination of MOFs with aptamers. Accordingly, this review article delineates recent innovations achieved for the aptamer-functionalized MOFs toward the detection of food contaminants. First, we describe the basic concepts involved in the detection of food contaminants in terms of the advantages and disadvantages of the commonly used analytical methods (e.g., DNA-based methods (PCR/real-time PCR/multiplex PCR/digital PCR) and protein-based methods (enzyme-linked immunosorbent assay/immunochromatography assay/immunosensor/mass spectrometry). Afterward, the progress in aptamer-functionalized MOF biosensors is discussed with respect to the sensing mechanisms (e.g., the role of MOFs as signal probes and carriers for loading signal probes) along with their performance evaluation (e.g., in terms of sensitivity). We finally discuss challenges and opportunities associated with the development of aptamer-functionalized MOFs for the measurement of food contaminants.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Humanos , Imunoensaio , Oligonucleotídeos , Alimento Processado
9.
Int J Biol Macromol ; 251: 126334, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37586631

RESUMO

In this study, antimicrobial biocomposite films based on gelatin-κ-carrageenan (Gκ) with 1, 2 and 4 % lactoferrin (L) loaded chromium-based metal-organic frameworks (L@Cr-MOFs) nanoparticles were synthesized by casting methods. The addition of L loaded Cr-MOFs into Gκ based films increased elongation at break from 2.19 to 14.92 % and decreased the tensile strength from 65.1 to 31.22 MPa. L@Cr-MOFs addition reduced swelling index (from 105 to 70.8 %), water solubility (from 61.3 to 34.63 %) and water vapor permeability (from 2.46 to 2.19 × 10-11 g. m/m2. s). When the additional amount was 4 wt%, the Gκ/L@Cr-MOFs films showed antibacterial effects against Escherichia coli and Staphylococcus aureus with the inhibition zone of 19.7 mm and 20.2 mm, respectively. In addition, strawberries preservation trial shown that the Gκ/L@Cr-MOFs films delayed the growth of spoilage molds on the surface of fruits. This research indicated that Gκ/L@Cr-MOFs are promising active packaging materials for the preservation of perishable fruits.

10.
Front Immunol ; 14: 1170475, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37483604

RESUMO

During B cell development in bone marrow, large precursor B cells (large Pre-B cells) proliferate rapidly, exit the cell cycle, and differentiate into non-proliferative (quiescent) small Pre-B cells. Dysregulation of this process may result in the failure to produce functional B cells and pose a risk of leukemic transformation. Here, we report that AT rich interacting domain 5B (ARID5B), a B cell acute lymphoblastic leukemia (B-ALL) risk gene, regulates B cell development at the Pre-B stage. In both mice and humans, we observed a significant upregulation of ARID5B expression that initiates at the Pre-B stage and is maintained throughout later stages of B cell development. In mice, deletion of Arid5b in vivo and ex vivo exhibited a significant reduction in the proportion of immature B cells but an increase in large and small Pre-B cells. Arid5b inhibition ex vivo also led to an increase in proliferation of both Pre-B cell populations. Metabolic studies in mouse and human bone marrow revealed that fatty acid uptake peaked in proliferative B cells then decreased during non-proliferative stages. We showed that Arid5b ablation enhanced fatty acid uptake and oxidation in Pre-B cells. Furthermore, decreased ARID5B expression was observed in tumor cells from B-ALL patients when compared to B cells from non-leukemic individuals. In B-ALL patients, ARID5B expression below the median was associated with decreased survival particularly in subtypes originating from Pre-B cells. Collectively, our data indicated that Arid5b regulates fatty acid metabolism and proliferation of Pre-B cells in mice, and reduced expression of ARID5B in humans is a risk factor for B cell leukemia.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras B , Fatores de Transcrição , Animais , Humanos , Camundongos , Proliferação de Células , Proteínas de Ligação a DNA/metabolismo , Ácidos Graxos , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Células Precursoras de Linfócitos B/metabolismo , Fatores de Transcrição/metabolismo
11.
J Environ Manage ; 344: 118379, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37329582

RESUMO

The Azo dyes are primarily utilized in textile industries. Treatment of textile wastewater because of the presence of recalcitrant dyes using conventional processes is greatly challenging and ineffective. So far, no experimental work has been conducted on the decolorization of Acid Red 182 (AR182) in aqueous media. Hence, in this novel experimental work, the treatment of AR182 from the Azo dyes family was explored using the electro-Peroxone (EP) process. For the optimization of operating factors, including AR182 concentration, pH, applied current, and O3 flowrate in the decolorization of AR182, Central Composite Design (CCD) was utilized. The statistical optimization presented a highly satisfactory determination coefficient value and a satisfactory second-order model. The expected optimum conditions by the experimental design were as the following: AR182 concentration at 483.12 mg.L-1, applied current at 0.627,113 A, pH at 8.18284 and O3 flowrate at 1.13548 L min-1. The current density is directly proportional to dye removal. However, increasing the amount of applied current beyond a critical value has a contradictory impact on dye removal performance. The dye removal performance in both acidic and highly alkaline environments was negligible. Hence, ascertaining the optimum pH value and conduction of the experiment at that point is critical. At optimum points, the decolorization performance in predicted and experimental conditions for AR182 were 99 and 98.5%, respectively. The outcomes of this work clearly substantiated that the EP can be successfully utilized for the decolorization of AR182 in textile wastewater.


Assuntos
Têxteis , Águas Residuárias , Rodaminas , Compostos Azo , Corantes , Indústria Têxtil
12.
Mikrochim Acta ; 190(7): 253, 2023 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-37286753

RESUMO

An innovative aptamer labeled with 5-FAM has been developed with a high affinity for Yersinia enterocolitica (Y. enterocolitica) using graphene oxide (GO) as a quenching platform. The selectivity of the prepared system was evaluated in the presence of common coexisted bacteria like Yersinia pseudotuberculosis, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, and Salmonella typhimurium. Some experimental factors like pH and stability were investigated. The results showed that in the absence of Y. enterocolitica, aptamer labeled with 5-FAM was bonded with GO, causing fluorescence to be relatively weak. After the addition of Y. enterocolitica, the aptamer is released from the GO surface and binds to the target bacteria, and significantly increases the fluorescence intensity with an excitation wavelength of 410 nm and an emission wavelength of 530 nm. After optimizing all conditions, the system exhibited a wide linear response for Y. enterocolitica in the concentration range 10 to 1.0 × 109 CFU•mL-1 and the limit of detection (LOD) was 3 CFU•mL-1. This system demonstrated that GO-designed aptamers can be successful in detecting Y. enterocolitica in whole-cell forms, making them potentially useful for screening and rapid detection.


Assuntos
Yersinia enterocolitica , Yersinia pseudotuberculosis , Limite de Detecção , Salmonella typhimurium , Oligonucleotídeos , Escherichia coli
13.
Adv Colloid Interface Sci ; 316: 102908, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37148581

RESUMO

Metal-organic frameworks (MOFs), also called porous coordination polymers, represent a class of crystalline porous materials made up of organic ligands and metal ions/metal clusters. Herein, an overview of the preparation of different metal-organic frameworks and the recent advances in MOF-based stimuli-responsive drug delivery systems (DDSs) with the drug release mechanisms including pH-, temperature-, ion-, magnetic-, pressure-, adenosine-triphosphate (ATP)-, H2S-, redox-, responsive, and photoresponsive MOF were rarely introduced. The combination therapy containing of two or more treatments can be enhanced treatment effectiveness through overcoming limitations of monotherapy. Photothermal therapy (PTT) combined with chemotherapy (CT), chemotherapy in combination with PTT or other combinations were explained to overcome drug resistance and side effects in normal cells as well as enhancing the therapeutic response. Integrated platforms containing of photothermal/drug-delivering functions with magnetic resonance imaging (MRI) properties exhibited great advantages in cancer therapy.


Assuntos
Estruturas Metalorgânicas , Estruturas Metalorgânicas/farmacologia , Estruturas Metalorgânicas/química , Sistemas de Liberação de Medicamentos , Metais
14.
Int J Biol Macromol ; 242(Pt 3): 125044, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37224901

RESUMO

In this study, pectin (PC)/chitosan nanofiber (ChNF) films containing a novel anthocyanin from sumac extract were successfully developed for freshness monitoring and shelf-life extension of shrimp. The physical, barrier, morphological, color, and antibacterial properties of biodegradable films were evaluated. The addition of sumac anthocyanins to the films caused intramolecular interactions (such as hydrogen bonds) in the film structure, as confirmed by using attenuated total reflectance Fourier transform infrared (ATR-FTIR) analysis, suggesting good compatibility of film ingredients. Also, intelligent films showed significant sensitivity to ammonia vapors and changed color from reddish to olive color at the first 5 min. Moreover, the results showed that PC/ChNF and PC/ChNF/sumac films have significant antibacterial activity against Gram-positive bacteria and Gram-negative bacteria. In addition to the good functional characteristics of the smart film, the resulting films showed acceptable physicomechanical properties. So, PC/ChNF/sumac smart film exhibited the strength = 60 MPa with the flexibility = 23.3 %. Likewise, water vapor barrier reduced from 2.5 (×10-11 g. m/m2. s. Pa) to 2.3 (×10-11 g. m/m2. s. Pa) after adding anthocyanin. The results of the application of intelligent film containing anthocyanins of sumac extract for shrimp freshness monitoring showed that the color of the intelligent film changed from reddish to greenish color after 48 h of storage, which shows the high potential of the produced film for monitoring the spoilage of seafood products.


Assuntos
Quitosana , Nanofibras , Rhus , Quitosana/química , Antocianinas/farmacologia , Antocianinas/química , Pectinas , Concentração de Íons de Hidrogênio , Alimentos Marinhos , Antibacterianos/farmacologia , Embalagem de Alimentos/métodos
15.
Comb Chem High Throughput Screen ; 26(15): 2598-2606, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36927436

RESUMO

Biogenic amines (BAs) are compounds deemed to be foodstuff contaminants and are the cause of poisoning or allergy. The main BAs found in foods include histamine, tyramine, putrescine, cadaverine, spermine and spermidine. The number of poisoning cases related to BAs in food has increased, which is reinforcing the need for BAs detection to ensure food safety. BAs are found in varying quantities in different foods such as fish, fruits, meat, cheese, vegetables, beer, and wine. Currently, different analytical techniques are used for BAs detection, as well as sample treatment methods that allow greater sensitivity, higher analyzing speed and lower detection limits. Moreover, BAs can be precursors of nitrosamines, which have been associated with mutagenic and carcinogenic activity. This review aims to provide a general approach to the different detection techniques of the BAs in foods, their concentrations and treatment methods.


Assuntos
Aminas Biogênicas , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida , Cromatografia Líquida de Alta Pressão/métodos , Aminas Biogênicas/análise , Aminas Biogênicas/química , Produtos Pesqueiros/análise
16.
Adv Pharm Bull ; 13(1): 134-142, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36721817

RESUMO

Purpose: This study aimed to investigate the effects of nanoliposomes containing crocin and nisin in milk samples as a food model. Therefore, three formulations were prepared and compared, including (1) milk samples containing free nisin and crocin, (2) samples with nanoliposomes containing nisin and crocin, and (3) nisin and crocin-loaded nanoliposomes coated with chitosan. Methods: In order to find the optimum amount of both bioactives within nanoliposomes, analyses of size, polydispersity index (PDI), zeta potential, and encapsulation efficiency were accomplished. Then, the best formulated nanoliposome was evaluated and compared with a solution containing free bioactives and nanoliposomes coated with chitosan using other experiments, including antioxidant and antibacterial activities, viscosity, colorimetric and bacterial growth. Results: The best nanoliposomal system based on the factors of size, PDI, zeta potential, and encapsulation efficiency was related for the nanocarrier with 4 mg crocin, 4.5 mg nisin, and 40 mg lecithin. Based on the results obtained, both nanoliposome (a*=5.41) and chitosancoated nanoliposome (a*=5.09) solutions could significantly (P<0.05) reduce the redness of milk induced by free bioactives (a*=12.32). However, viscosity of milk in chitosan-coated nanoliposome solution was found to be higher (3.42 cP) than other formulations (viscosity of samples with free bioactives was 1.65 cP and viscosity of samples containing nanoliposome was 1.71 cP). In addition, chitosan-coated nanoliposomes could inhibit the growth of Listeria monocytogenes stronger than other samples. Conclusion: Encapsulation of nisin and crocin in nanoliposomes showed promising results for preserving food safety and quality.

17.
Biosensors (Basel) ; 13(1)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36671929

RESUMO

In this research, a simple, label-free, and ultra-sensitive fluorescent platform based on a metal-organic framework (MOF) has been developed to detect melamine in milk powder. This fluorescence sensor was fabricated from sensitized terbium (Tb)@NH2-MIL-253 (Al) MOF using a hydrothermal method that involved combining the green emission of Tb (λem = 545 nm) with the blue emission of NH2-MIL-253(Al) MOF (λem = 430 nm) under a single excitation wavelength (λex = 335 nm). The fluorescence sensor was then used under optimized conditions (pH = 9.0; sensor concentration = 30 mg/L; response time = 30 s) to quantify melamine in milk powder. The accuracy, sensitivity, and reproducibility of this sensor were established compared to the high-performance liquid chromatography (HPLC) method. The linear range and lower limit of detection (LLOD, computed with 3σ/S) of the sensor were between 40-396.45 nM (equal to 25 µg/kg-0.25 mg/kg) and 40 nM (equal to 25 µg/kg), respectively, which is much less than the maximum residual level (MRL) for the detection of melamine in infant formula (1 mg/kg) and other foods/feeds (2.5 mg/kg). Additionally, the results had good agreement with the HPLC outcomes, suggesting that the NH2-MIL-253(Al) MOF sensing probe has great precision and repeatability. To conclude, the new fluorescence sensor developed in this study can accurately and sensitively detect melamine in food samples, which may be useful for screening for adulteration of milk powders and other foods.


Assuntos
Estruturas Metalorgânicas , Humanos , Animais , Estruturas Metalorgânicas/química , Pós/análise , Leite/química , Reprodutibilidade dos Testes , Limite de Detecção
18.
Crit Rev Food Sci Nutr ; 63(19): 4009-4025, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34751073

RESUMO

As a bioactive component in Capsicum species, capsaicin is a compound of hot chili peppers which is known as the main substance responsible for the spiciness of these fruits. Besides its taste and physiological effects, it exhibits good antioxidant activity in food matrix and antimicrobial activity against foodborne pathogens and viruses. Considering its low stability and bioaccessibility, and also regarding its irritation, the entrapment methods of capsaicin are fully developed. To compensate the limitations of capsaicin, various encapsulation methods have been used so far, including coacervation, emulsion, spray chilling, and liposomal delivery. Capsaicin has been widely used as a flavoring and preservative agent in food formulations and even as an active compound in packaging film and functional foods. This review provides an overview of the techno-functional properties, stabilization procedures, and burgeoning usages of capsaicin in the latest studies of the food sector. So, it may introduce new windows for the application of this compound.


Assuntos
Capsaicina , Capsicum , Capsaicina/farmacologia , Frutas/química , Indústria Alimentícia , Antioxidantes/farmacologia
19.
J Hum Nutr Diet ; 36(1): 181-190, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35822612

RESUMO

BACKGROUND: Contaminated blenderised tube feeding (BTF) causes numerous infections in patients with deficient immune systems. The microbial quality of BTF should be thoroughly monitored to reduce the risks of microbial agents and prevent food safety problems such as food poisoning and food-borne illnesses. The aim of this study was to survey the contamination rate of BTF samples prepared in the teaching hospitals in Mashhad, Iran. METHODS: This study was conducted on 24 samples of BTF prepared in four teaching hospitals in Mashhad city; the samples were collected randomly. Then specific culture media were used for detected and counted Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, Clostridium perfringens, Bacillus cereus, coliforms and Escherichia coli. The final confirmation of the isolates was performed using polymerase chain reaction. RESULTS: The total bacterial count was determined in the BTF samples and compared with the Food and Drug Administration medical food standards; 91.6% of the samples had 5.2 ± 0.1 log CFU/ml microbial bacterial contamination considering the standard range. The mean prevalence of contamination in these samples was measured for coliforms 4.9 ± 0.17 log CFU/ml, B. cereus 3.6 ± 0.16 log CFU/ml, S. aureus 3.7 ± 0.15 log CFU/ml and C. perfringens 4.7 ± 0.08 log CFU/ml (p < 0.05). Moreover, E. coli 11 (45.8%), Salmonella spp. 9 (37.5%) and L. monocytogenes 17 (70.8%) samples were detected. CONCLUSION: Given the high consumption of BTF and the transmission of food contamination to hospitalised patients, it is essential to improve the hygienic conditions at the site of BTF preparation to prevent re-contamination.


Assuntos
Microbiologia de Alimentos , Doenças Transmitidas por Alimentos , Estados Unidos , Humanos , Escherichia coli , Nutrição Enteral , Staphylococcus aureus , Manipulação de Alimentos , Contagem de Colônia Microbiana , Doenças Transmitidas por Alimentos/prevenção & controle , Salmonella , Hospitais
20.
Int J Biol Macromol ; 234: 122944, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36549625

RESUMO

The purpose of the current investigation was to produce a novel functional composite biodegradable film by Gellan (Gla) and Carboxymethyl cellulose (CMC) biopolymers containing rosemary essential oils (REO) and evaluate their physicochemical and antimicrobial features. The film containing 5 % REO, due to its better mechanical properties (UTS = 13.44 ± 0.30 Mpa and SB = 21.14 ± 1.15 %) compared to other emulsified samples containing REO, was selected as the optimal film. Furthermore, it had less water vapor permeability (WVP = 6.60 ± 0.31 (g/mhPa) × 10-8) in comparison to control sample (8.21 ± 0.10 (g/mhPa) × 10-8) and the best color properties among the samples. The Scanning Electron Microscopy (SEM) images didn't show the phenomenon of agglomeration and point accumulation of REO. Also, 5 % of REO contributed to the increased compactness of the film in comparison to the film without the REO. Based on the results of Fourier-transform infrared spectroscopy (FTIR) spectra, no new chemical bonds were created by adding REO to the biopolymer substrate, and the REO was well dispersed and distributed among the Gla-CMC chains throughout the film substrate. Adding 5 % REO showed antioxidant effects. Considering the antimicrobial tests, all films containing REO had antimicrobial effects against the Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, and Pseudomonas fluorescens bacterial strains.


Assuntos
Anti-Infecciosos , Óleos Voláteis , Rosmarinus , Antibacterianos/farmacologia , Antibacterianos/química , Carboximetilcelulose Sódica/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Biopolímeros/farmacologia , Escherichia coli , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Embalagem de Alimentos/métodos
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