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1.
J Agric Food Chem ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728528

RESUMO

In this study, we devised a photothermally stable phytochemical dye by leveraging alizarin in conjunction with the metal-organic framework ZIF-8 (AL@ZIF-8). The approach involved grafting alizarin into the microporous structure of ZIF-8 through physical adsorption and hydrogen-bonding interactions. AL@ZIF-8 significantly enhanced the photostability and thermostability of alizarin. The nanoparticles demonstrate substantial color changes in various pH environments, showcasing their potential for meat freshness monitoring. Furthermore, we introduced an intelligent film utilizing poly(vinyl alcohol)-sodium alginate-AL@ZIF-8 (PA-SA-ZA) for detecting beef freshness. The sensor exhibited a superior water contact angle (52.34°) compared to the alizarin indicator. The color stability of the film was significantly enhanced under visible and UV light (ΔE < 5). During beef storage, the film displayed significant color fluctuations correlating with TVB-N (R2=0.9067), providing precise early warning signals for assessing beef freshness.

2.
Foods ; 13(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38611406

RESUMO

In this work, a gelatin/chia mucilage (GN/CM) composite coating material doped with Lactococcus lactis (LS) was developed for strawberry preservation applications. The results of the scanning electron microscope and Fourier transform infrared spectroscopy stated that the enhanced molecular interaction between the CM and GN matrix strengthened the density and compactness of the GN film. Antifungal results indicated that the addition of LS significantly (p < 0.05) improved the ability of the GN coating to inhibit the growth of Botrytis cinerea (inhibition percentage = 62.0 ± 4.6%). Adding CM significantly (p < 0.05) decreased the water vapour permeability and oxygen permeability of the GN coating by 32.7 ± 4.0% and 15.76 ± 1.89%, respectively. In addition, the incorporated CM also significantly (p < 0.05) improved the LS viability and elongation at break of the film by 13.11 ± 2.05% and 42.58 ± 1.21%, respectively. The GN/CM/LS composite coating material also exhibited an excellent washability. The results of this study indicated that the developed GN/CM/LS coating could be used as a novel active material for strawberry preservation.

3.
Cell Mol Biol (Noisy-le-grand) ; 70(3): 174-181, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38650145

RESUMO

Ovarian cancer is a prevalent malignancy in the female reproductive system, representing a significantly fatal and incurable tumor. Chelerythrine (CHE), a natural benzopyridine alkaloid, has demonstrated a broad spectrum of anticancer activities. Nevertheless, the ovarian cancer inhibitory impact of CHE remains unclear. In this study, we investigated the cytotoxic mechanism and potential targets of CHE on in vitro cultures of A2780 and SKOV3 cells derived from ovarian cancer. Additionally, in vivo experiments were conducted to confirm the suppressive impact of CHE on tumor growth in nude mice. The findings revealed that CHE impeded the growth of A2780 and SKOV3 cells in a concentration-time-dependent manner and significantly suppressed the development of tumors in nude mice. CHE elevated the level of oxidative stress in tumor cells, prompted cell cycle halt in the S phase, and increased their mitochondrial membrane potential. Western blotting results demonstrated that CHE could modulate the expression of proteins associated with apoptotic and ferroptosis processes in A2780 and SKOV3 cells. Nrf2 was verified to be an upstream key target mediating the inhibitory impact of CHE on ovarian cancer cells. In summary, CHE exerts its anti-cancer effects on ovarian cancer by modulating Nrf2, inhibiting cellular proliferation, and promoting apoptosis and ferroptosis.


Assuntos
Apoptose , Benzofenantridinas , Proliferação de Células , Ferroptose , Camundongos Nus , Fator 2 Relacionado a NF-E2 , Neoplasias Ovarianas , Feminino , Benzofenantridinas/farmacologia , Humanos , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Linhagem Celular Tumoral , Ferroptose/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
4.
EClinicalMedicine ; 71: 102580, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38618206

RESUMO

Background: The pathological examination of lymph node metastasis (LNM) is crucial for treating prostate cancer (PCa). However, the limitations with naked-eye detection and pathologist workload contribute to a high missed-diagnosis rate for nodal micrometastasis. We aimed to develop an artificial intelligence (AI)-based, time-efficient, and high-precision PCa LNM detector (ProCaLNMD) and evaluate its clinical application value. Methods: In this multicentre, retrospective, diagnostic study, consecutive patients with PCa who underwent radical prostatectomy and pelvic lymph node dissection at five centres between Sep 2, 2013 and Apr 28, 2023 were included, and histopathological slides of resected lymph nodes were collected and digitised as whole-slide images for model development and validation. ProCaLNMD was trained at a dataset from a single centre (the Sun Yat-sen Memorial Hospital of Sun Yat-sen University [SYSMH]), and externally validated in the other four centres. A bladder cancer dataset from SYSMH was used to further validate ProCaLNMD, and an additional validation (human-AI comparison and collaboration study) containing consecutive patients with PCa from SYSMH was implemented to evaluate the application value of integrating ProCaLNMD into the clinical workflow. The primary endpoint was the area under the receiver operating characteristic curve (AUROC) of ProCaLNMD. In addition, the performance measures for pathologists with ProCaLNMD assistance was also assessed. Findings: In total, 8225 slides from 1297 patients with PCa were collected and digitised. Overall, 8158 slides (18,761 lymph nodes) from 1297 patients with PCa (median age 68 years [interquartile range 64-73]; 331 [26%] with LNM) were used to train and validate ProCaLNMD. The AUROC of ProCaLNMD ranged from 0.975 (95% confidence interval 0.953-0.998) to 0.992 (0.982-1.000) in the training and validation datasets, with sensitivities > 0.955 and specificities > 0.921. ProCaLNMD also demonstrated an AUROC of 0.979 in the cross-cancer dataset. ProCaLNMD use triggered true reclassification in 43 (4.3%) slides in which micrometastatic tumour regions were initially missed by pathologists, thereby correcting 28 (8.5%) missed-diagnosed cases of previous routine pathological reports. In the human-AI comparison and collaboration study, the sensitivity of ProCaLNMD (0.983 [0.908-1.000]) surpassed that of two junior pathologists (0.862 [0.746-0.939], P = 0.023; 0.879 [0.767-0.950], P = 0.041) by 10-12% and showed no difference to that of two senior pathologists (both 0.983 [0.908-1.000], both P > 0.99). Furthermore, ProCaLNMD significantly boosted the diagnostic sensitivity of two junior pathologists (both P = 0.041) to the level of senior pathologists (both P > 0.99), and substantially reduced the four pathologists' slide reviewing time (-31%, P < 0.0001; -34%, P < 0.0001; -29%, P < 0.0001; and -27%, P = 0.00031). Interpretation: ProCaLNMD demonstrated high diagnostic capabilities for identifying LNM in prostate cancer, reducing the likelihood of missed diagnoses by pathologists and decreasing the slide reviewing time, highlighting its potential for clinical application. Funding: National Natural Science Foundation of China, the Science and Technology Planning Project of Guangdong Province, the National Key Research and Development Programme of China, the Guangdong Provincial Clinical Research Centre for Urological Diseases, and the Science and Technology Projects in Guangzhou.

5.
Anal Chim Acta ; 1304: 342515, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38637032

RESUMO

Aiming for sustainable crop productivity under changing climate conditions, it is essential to develop handy models for in-situ monitoring of reactive oxygen species (ROS). Herein, this work reports a simple electrochemical sensing toward hydrogen peroxide (H2O2) for tracking crop growth status sensitized with electron-migration nanostructure. To be specific, Cu-based metal-organic frameworks (MOFs) with high HOMO energy level are designed for H2O2 reduction on account of Cu(I)/Cu(II) redox switchability. Importantly, the sensing performance is improved by electrochemically reduced graphene oxide (GO) with ready to use feature. To overcome the shortcomings of traditional liquid electrolytes, conductive hydrogel as semi-solid electrolyte exhibits the adhesive property to the cut plant petiole surface. Benefitting from the preferred composite models and conductive hydrogel, the electrochemical sensing toward H2O2 with high sensitivity and good anti-interference against the coexistent molecules, well qualified for acquiring plant growth status.

6.
EClinicalMedicine ; 71: 102566, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38686219

RESUMO

Background: Urine cytology is an important non-invasive examination for urothelial carcinoma (UC) diagnosis and follow-up. We aimed to explore whether artificial intelligence (AI) can enhance the sensitivity of urine cytology and help avoid unnecessary endoscopy. Methods: In this multicentre diagnostic study, consecutive patients who underwent liquid-based urine cytology examinations at four hospitals in China were included for model development and validation. Patients who declined surgery and lacked associated histopathology results, those diagnosed with rare subtype tumours of the urinary tract, or had low-quality images were excluded from the study. All liquid-based cytology slides were scanned into whole-slide images (WSIs) at 40 × magnification and the WSI-labels were derived from the corresponding histopathology results. The Precision Urine Cytology AI Solution (PUCAS) was composed of three distinct stages (patch extraction, features extraction, and classification diagnosis) and was trained to identify important WSI features associated with UC diagnosis. The diagnostic sensitivity was mainly used to validate the performance of PUCAS in retrospective and prospective validation cohorts. This study is registered with the ChiCTR, ChiCTR2300073192. Findings: Between January 1, 2018 and October 31, 2022, 2641 patients were retrospectively recruited in the training cohort, and 2335 in retrospective validation cohorts; 400 eligible patients were enrolled in the prospective validation cohort between July 7, 2023 and September 15, 2023. The sensitivity of PUCAS ranged from 0.922 (95% CI: 0.811-0.978) to 1.000 (0.782-1.000) in retrospective validation cohorts, and was 0.896 (0.837-0.939) in prospective validation cohort. The PUCAS model also exhibited a good performance in detecting malignancy within atypical urothelial cells cases, with a sensitivity of over 0.84. In the recurrence detection scenario, PUCAS could reduce 57.5% of endoscopy use with a negative predictive value of 96.4%. Interpretation: PUCAS may help to improve the sensitivity of urine cytology, reduce misdiagnoses of UC, avoid unnecessary endoscopy, and reduce the clinical burden in resource-limited areas. The further validation in other countries is needed. Funding: National Natural Science Foundation of China; Key Program of the National Natural Science Foundation of China; the National Science Foundation for Distinguished Young Scholars; the Science and Technology Planning Project of Guangdong Province; the National Key Research and Development Programme of China; Guangdong Provincial Clinical Research Centre for Urological Diseases.

7.
Compr Rev Food Sci Food Saf ; 23(3): e13339, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38578165

RESUMO

The importance of food quality and safety lies in ensuring the best product quality to meet consumer demands and public health. Advanced technologies play a crucial role in minimizing the risk of foodborne illnesses, contamination, drug residue, and other potential hazards in food. Significant materials and technological advancements have been made throughout the food supply chain. Among them, quantum dots (QDs), as a class of advanced nanomaterials with unique physicochemical properties, are progressively demonstrating their value in the field of food quality and safety. This review aims to explore cutting-edge research on the different applications of QDs in food quality and safety, including encapsulation of bioactive compounds, detection of food analytes, food preservation and packaging, and intelligent food freshness indicators. Moreover, the modification strategies and potential toxicities of diverse QDs are outlined, which can affect performance and hinder applications in the food industry. The findings suggested that QDs are mainly used in analyte detection and active/intelligent food packaging. Various food analytes can be detected using QD-based sensors, including heavy metal ions, pesticides, antibiotics, microorganisms, additives, and functional components. Moreover, QD incorporation aided in improving the antibacterial and antioxidant activities of film/coatings, resulting in extended shelf life for packaged food. Finally, the perspectives and critical challenges for the productivity, toxicity, and practical application of QDs are also summarized. By consolidating these essential aspects into this review, the way for developing high-performance QD-based nanomaterials is presented for researchers and food technologists to better capitalize upon this technology in food applications.


Assuntos
Pontos Quânticos , Pontos Quânticos/toxicidade , Contaminação de Alimentos/prevenção & controle , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Qualidade dos Alimentos , Embalagem de Alimentos/métodos
8.
Small ; : e2312129, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593332

RESUMO

Lithium (Li) metal is widely recognized as a viable candidate for anode material in future battery technologies due to its exceptional energy density. Nevertheless, the commercial Li foils in common use are too thick (≈100 µm), resulting in a waste of Li resources. Herein, by applying the vacuum evaporation plating technology, the ultra-thin Li foils (VELi) with high purity, strong adhesion, and thickness of less than 10 µm are successfully prepared. The manipulation of evaporation temperature allows for convenient regulation of the thickness of the fabricated Li film. This physical thinning method allows for fast, continuous, and highly accurate mass production. With a current density of 0.5 mA cm-2 for a plating amount of 0.5 mAh cm-2, VELi||VELi cells can stably cycle for 200 h. The maximum utilization of Li is already more than 25%. Furthermore, LiFePO4||VELi full cells present excellent cycling performance at 1 C (1 C = 155 mAh g-1) with a capacity retention rate of 90.56% after 240 cycles. VELi increases the utilization of active Li and significantly reduces the cost of Li usage while ensuring anode cycling and multiplication performance. Vacuum evaporation plating technology provides a feasible strategy for the practical application of ultra-thin Li anodes.

9.
CNS Neurosci Ther ; 30(3): e14663, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38439636

RESUMO

BACKGROUND: Epilepsy is a widespread and chronic disease of the central nervous system caused by a variety of factors. Mitochondrial ferritin (FtMt) refers to ferritin located within the mitochondria that may protect neurons against oxidative stress by binding excess free iron ions in the cytoplasm. However, the potential role of FtMt in epilepsy remains unclear. We aimed to investigate whether FtMt and its related mechanisms can regulate epilepsy by modulating ferroptosis. METHODS: Three weeks after injection of adeno-associated virus (AAV) in the skull of adult male C57BL/6 mice, kainic acid (KA) was injected into the hippocampus to induce seizures. Primary hippocampal neurons were transfected with siRNA using a glutamate-mediated epilepsy model. After specific treatments, Western blot analysis, immunofluorescence, EEG recording, transmission electron microscopy, iron staining, silver staining, and Nissl staining were performed. RESULTS: At different time points after KA injection, the expression of FtMt protein in the hippocampus of mice showed varying degrees of increase. Knockdown of the FtMt gene by AAV resulted in an increase in intracellular free iron levels and a decrease in the function of iron transport-related proteins, promoting neuronal ferroptosis and exacerbating epileptic brain activity in the hippocampus of seizure mice. Additionally, increasing the expression level of FtMt protein was achieved by AAV-mediated upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) gene in the hippocampus of seizure mice. CONCLUSIONS: In epilepsy, Nrf2 modulates ferroptosis by involving the expression of FtMt and may be a potential therapeutic mechanism of neuronal injury after epilepsy. Targeting this relevant process for treatment may be a therapeutic strategy to prevent epilepsy.


Assuntos
Epilepsia , Ferroptose , Masculino , Animais , Camundongos , Camundongos Endogâmicos C57BL , Ácido Caínico/toxicidade , Fator 2 Relacionado a NF-E2/genética , Epilepsia/induzido quimicamente , Convulsões , Ácido Glutâmico , Dependovirus , Modelos Animais de Doenças , Ferritinas , Homeostase
10.
Int J Biol Macromol ; 266(Pt 2): 131000, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521333

RESUMO

In recent years, the development of probiotic film by incorporating probiotics into edible polymers has attracted significant research attention in the field of active packaging. However, the influence of the external environment substantially reduces the vitality of probiotics, limiting their application. Therefore, to improve the probiotic activity, this study devised a novel nanofiber film incorporating chia mucilage protection solution (CPS), gum arabic (GA), pullulan (PUL), and Lactobacillus bulgaricus (LB). SEM images indicated the successful preparation of the nanofiber film incorporating LB. CPS incorporation significantly improved the survival ability of LB, with a live cell count reaching 7.62 log CFU/g after 28 days of storage at 4 °C - an increase of 1 log CFU/g compared to the fiber film without CPS. The results showed that the fiber film containing LB inhibited Escherichia coli and Staphylococcus aureus. Finally, the novel probiotic nanofiber film was applied to beef. The results showed that the shelf life of the beef during the experiments was extended for 2 days at 4 °C. Therefore, the novel probiotic film containing LB was suitable for meat preservation.


Assuntos
Antibacterianos , Glucanos , Goma Arábica , Nanofibras , Nanofibras/química , Glucanos/química , Glucanos/farmacologia , Goma Arábica/química , Antibacterianos/farmacologia , Antibacterianos/química , Salvia/química , Lactobacillus delbrueckii , Probióticos/química , Animais , Conservação de Alimentos/métodos , Carne Vermelha/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Mucilagem Vegetal/química , Escherichia coli/efeitos dos fármacos , Bovinos , Embalagem de Alimentos/métodos
12.
Environ Res ; 251(Pt 2): 118708, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38493858

RESUMO

The mode of action (MOA) framework is proposed to inform a biological link between chemical exposures and adverse health effects. Despite a significant increase in knowledge and awareness, the application of MOA in human health risk assessment (RA) remains limited. This study aims to discuss the adoption of MOA for health RA within a regulatory context, taking our previously proposed but not yet validated MOA for lead neurotoxicity as an example. We first conducted a quantitative weight of evidence (qWOE) assessment, which revealed that the MOA has a moderate confidence. Then, targeted bioassays were performed within an in vitro blood-brain barrier (BBB) model to quantitatively validate the scientific validity of key events (KEs) in terms of essentiality and concordance of empirical support (dose/temporal concordance), which increases confidence in utilizing the MOA for RA. Building upon the quantitative validation data, we further conducted benchmark dose (BMD) analysis to map dose-response relationships for the critical toxicity pathways, and the lower limit of BMD at a 5% response (BMDL5) was identified as the point of departure (POD) value for adverse health effects. Notably, perturbation of the Aryl Hydrocarbon Receptor (AHR) signaling pathway exhibited the lowest POD value, measured at 0.0062 µM. Considering bioavailability, we further calculated a provisional health-based guidance value (HBGV) for children's lead intake, determining it to be 2.56 µg/day. Finally, the health risk associated with the HBGV was assessed using the hazard quotient (HQ) approach, which indicated that the HBGV established in this study is a relative safe reference value for lead intake. In summary, our study described the procedure for utilizing MOA in health RA and set an example for MOA-based human health risk regulation.

13.
Mol Neurobiol ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546929

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the abnormal aggregation of α-synuclein (α-syn) and the loss of dopaminergic neurons. Although microbial infection has been implicated in the pathogenesis of PD, the associated virulence factors and the underlying molecular mechanisms require further elucidation. Here, we found that intestinal infection with Nocardia farcinica induced a series of PD-like symptoms in Caenorhabditis elegans, such as the accelerated degeneration of dopaminergic neurons, impaired locomotion capacity, and enhanced α-syn aggregation, through the disturbance of mitochondrial functions. To identify the potential virulence factors involved in these effects, we knocked out the nbtB/C and nbtS genes in N. farcinica, which are localized in the gene clusters responsible for nocobactin biosynthesis. The deletion of either gene partially rescued the degenerative effects of wild-type N. farcinica on dopaminergic neurons by attenuating mitochondrial dysfunction. LC-MS analysis further identified a decrease in the abundance of several siderophores in the two mutants, including nocobactin NA-a, nocobactin NA-b, and nocardimicin B. Collectively, our results demonstrated that intestinal N. farcinica infection in C. elegans facilitates PD-like pathogenesis and provides novel evidence for the involvement of pathogenic bacteria in neurodegenerative diseases via non-neuroinvasive mechanisms.

14.
Cancer Lett ; 587: 216728, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38431036

RESUMO

Lysosomes are crucial organelles responsible for the degradation of cytosolic materials and bulky organelles, thereby facilitating nutrient recycling and cell survival. However, lysosome also acts as an executioner of cell death, including ferroptosis, a distinctive form of regulated cell death that hinges on iron-dependent phospholipid peroxidation. The initiation of ferroptosis necessitates three key components: substrates (membrane phospholipids enriched with polyunsaturated fatty acids), triggers (redox-active irons), and compromised defence mechanisms (GPX4-dependent and -independent antioxidant systems). Notably, iron assumes a pivotal role in ferroptotic cell death, particularly in the context of cancer, where iron and oncogenic signaling pathways reciprocally reinforce each other. Given the lysosomes' central role in iron metabolism, various strategies have been devised to harness lysosome-mediated iron metabolism to induce ferroptosis. These include the re-mobilization of iron from intracellular storage sites such as ferritin complex and mitochondria through ferritinophagy and mitophagy, respectively. Additionally, transcriptional regulation of lysosomal and autophagy genes by TFEB enhances lysosomal function. Moreover, the induction of lysosomal iron overload can lead to lysosomal membrane permeabilization and subsequent cell death. Extensive screening and individually studies have explored pharmacological interventions using clinically available drugs and phytochemical agents. Furthermore, a drug delivery system involving ferritin-coated nanoparticles has been specifically tailored to target cancer cells overexpressing TFRC. With the rapid advancements in understandings the mechanistic underpinnings of ferroptosis and iron metabolism, it is increasingly evident that lysosomes represent a promising target for inducing ferroptosis and combating cancer.


Assuntos
Ferro , Neoplasias , Humanos , Morte Celular , Ferro/metabolismo , Ferritinas/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Lisossomos/metabolismo
15.
Int J Biol Macromol ; 265(Pt 1): 130466, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432274

RESUMO

A novel colorimetric aerogel was developed by the complexation of carboxymethyl cellulose (CMC), sodium alginate (SA), and black goji anthocyanin (BGA) followed by freeze-drying for monitoring fish (Coho salmon) freshness during storage at 4 °C and 25 °C. The various aerogels (C/S/B3:1, C/S/B2:1, C/S/B1:1, C/S/B1:2, and C/S/B1:3) externally and internally were characterized using SEM, FTIR, XRD, DSC, and TGA. Among them, the aerogel composite C/S/B1:2 exhibited the most uniform pore size, largest specific surface area, rapid color changes in various alkaline vapors (5 µM and 50 µM), and better mechanical strength. Furthermore, the colorimetric aerogel became dark blue from light purple during fish storage at temperatures of 4 °C and 25 °C when it reached pH 7.49 and 7.33, TVC 8.9 × 107 CFU/g and 8.5 × 107 CFU/g, and TVB-N 33.8 mg/100 g and 26.12 mg/100 g, respectively, indicating fish completely deteriorated. Taken together, the colorimetric aerogel composite C/S/B1:2 was promising for determining fish freshness, which could be utilized as a non-destructive and useful intelligent sensor in monitoring various fish and meat freshness and/or quality.


Assuntos
Alginatos , Carboximetilcelulose Sódica , Animais , Carboximetilcelulose Sódica/química , Antocianinas/química , Colorimetria , Embalagem de Alimentos
16.
Food Chem ; 447: 138663, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38489878

RESUMO

The combination of carbon dots (CDs) with covalent organic frameworks (COFs) was used to design an innovative sensor based on fluorescence resonance energy transfer (FRET) for the detection of Escherichia coli O157:H7 (E. coli O157:H7) in food samples. Carbon dots were used as fluorescence donors, covalent organic frameworks as fluorescence acceptors. The antibody (Ab) specific to E. coli O157:H7 was used to form a CD-Ab-COF immunosensor by linking CDs and COFs. The antibody was specifically bound with E. coli O157:H7, which caused the connection between CDs and COFs to be interrupted, and the carbon dots exhibited fluorescence restoration. The sensor exhibited a linear detection range spanning from 0 to 106 CFU/mL, with the limit of detection (LOD) of 7 CFU/mL. The analytical performance of the developed immunosensor was evaluated using spiked food samples with different concentrations of E. coli O157:H7, validating the capability of assessing risks in food testing.


Assuntos
Técnicas Biossensoriais , Escherichia coli O157 , Estruturas Metalorgânicas , Transferência Ressonante de Energia de Fluorescência , Carbono , Imunoensaio , Anticorpos
17.
Food Chem ; 444: 138467, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38309078

RESUMO

Packaging plays an important role in protecting food from environmental impacts. However, traditional petroleum-based packaging has difficulty in meeting the antimicrobial and antioxidant requirements of prepared foods. This study introduced carbon dots (CDs), prepared by using carrot as a precursor, into corn starch (CS) to construct a bio-friendly composite film with high freshness retention properties. The scavenging of DPPH radicals reached 92.77 % at a CDs concentration of 512 µg/mL, and the antimicrobial activity of CS/5% CDs against Escherichia coli and Staphylococcus aureus was increased to 99.9 %. Notably, the homogeneous doping of CDs creates a dense surface and high carbon content inside the film, which promotes the elasticity and thermal stability of the composite film. Finally, we encapsulated deep-fried meatballs in CS-CDs films. The results showed that the CS-CDs films effectively protected the quality of deep-fried meatballs, and have excellent potential for application in food preservation.


Assuntos
Anti-Infecciosos , Quitosana , Embalagem de Alimentos/métodos , Zea mays , Amido/química , Quitosana/química , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Infecciosos/química
18.
Foods ; 13(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38338639

RESUMO

Accurate assessment of dough kneading is pivotal in pasta processing, where both under-kneading and over-kneading can detrimentally impact dough quality. This study proposes an innovative approach utilizing a cost-effective current sensor to ascertain the optimal kneading time for dough. Throughout the kneading process, the dough's tensile resistance gradually increases, reflecting the evolution of properties such as the gluten network. This leads to a discernible ascending phase in dough quality, evident through an increase in the load current of the mixing machine, succeeded by a subsequent decline beyond a certain threshold. The identification of this peak point enables the achievement of optimal dough consistency, thereby enhancing the overall quality of both the dough and subsequent pasta products. After the final product quality assessment, this novel method promises to be a valuable tool in optimizing pasta processing and ensuring consistent product quality.

19.
Anal Chim Acta ; 1292: 342199, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38309856

RESUMO

In this study, a bimetallic surfaced-enhanced Raman spectroscopy (SERS)-active substrate consisting of AuNR@AgNCs was proposed for the rapid detection of dithianon. Due to the significant synergistic enhancement of the core-shell nanocuboids, the obtained AuNR@AgNC substrate exhibited excellent SERS performance. The simulation findings supported the practical SERS results and demonstrated that interactions were mainly maintained by the nitrile functional group. The AuNR@AgNCs could be used to detect dithianon with an LOD value of 20 nM. Moreover, dithianon in river water and apple juice could be detected with recovery in the satisfactory ranges of 97.41%-98.35% and 97.77%-98.70%, respectively, by using this substrate under optimal conditions, indicating that the AuNR@AgNC substrate could serve as an excellent SERS detection platform for pesticide residues in fruit.


Assuntos
Malus , Nanopartículas Metálicas , Resíduos de Praguicidas , Análise Espectral Raman/métodos , Malus/química , Resíduos de Praguicidas/análise , Frutas/química , Sucos de Frutas e Vegetais , Ouro/química , Nanopartículas Metálicas/química
20.
Foods ; 13(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38254550

RESUMO

As a traditional Chinese dish cutting technology process, Gaidao artificially create cuts embedded in the food surface by cutting through it with knife, a process that currently plays an important role in the beef marinating process. And different Gaidao processes directly affect the beef marination flavour and marination efficiency. This study is the first to propose the use of Hyperspectral imaging technology (HSI) combined with finite element analysis to investigate the effect of Gaidao process on the quality of marinated beef. The study was carried out by collecting spectral information of beef marinated with different sucrose concentrations and combining various pre-processing methods and algorithms such as PLS, BiPLS, iPLS, and SiPLS to establish a quantitative model of sucrose concentration in beef, and finally optimizing parameters such as the length, position and number of Gaidao by Finite Element Analysis (FEA), which showed that when marinated with 1.0 mol/m³ sucrose solution, the concentration of sucrose in all tissues in the Gaidao steak reached 0.8 mol/m³ and above, which greatly improved the diffusion effect of the marinade. This work provides new ideas and methods to optimize the beef marinade Gaidao process, which has important practical value and research significance.

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