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1.
Biomacromolecules ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956952

RESUMEN

The surface of food processing equipment is easily affected by biofilm-forming bacteria, leading to cross-contamination and food safety hazards. The critical issue is how to endow the surface of contact materials with antibacterial and antibiofilm abilities. A sustainable, stable, and antibiofilm coating was prepared by phase transition of glutenin. The disulfide bonds in glutenin were reduced by tris(2-carboxyethyl)phosphine, triggering the phase transition of glutenin. Hydrophobic interactions and intermolecular disulfide bonds may be the primary forces. Furthermore, the phase-transited products formed a nanoscale coating on the surface of stainless steel and glass under their own adhesion force and gravity. The coating exhibited good stability in harsh environments. More importantly, after 3 h of direct contact, the colony of Escherichia coli and Staphylococcus aureus decreased by one logarithm. The amount of biofilm was observed to be significantly decreased through optical microscopy and scanning electron microscopy. This article provides a foundational module for developing novel coatings.

2.
Environ Res ; 259: 119498, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38942254

RESUMEN

Microplastics (MPs) can enter the reproductive system and can be potentially harmful to human reproductive health. In this study, 13 types of microplastics (MPs) were identified in patient blood, cancer samples, and paracarcinoma samples using Raman spectroscopy, with polyethylene, polypropylene and polyethylene-co-polypropylene being the most abundant polymer types. Futher, cotton was also found in our study. The diversity and abundance of MPs were higher in blood samples than in cancerous tissues, and there was a significant positive correlation between diversity (p < 0.05). Furthermore, the diversity and abundance of MPs in cancerous tissues were higher than in paracancerous tissues. The dimensional sizes of MPs in these samples were also very similar, with the majority of detected MPs being smaller in size. Correlation analysis showed that patient's age correlated with the abundance of MPs in blood samples, body mass index (BMI) correlated with the abundance of MPs in cancerous tissues. Notably, the frequency with which patients consume bottled water and beverages may also increase the abundance of MPs. This study identifies for the first time the presence of MPs and cotton in cancerous and paracancerous tissues of human cervical cancer patients. This provides new ideas and basic data to study the risk relationship between MP exposure and human health.

3.
Food Microbiol ; 117: 104387, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37919011

RESUMEN

Ultrasonic treatment is widely used for surface cleaning of vegetables in the processing of agricultural products. In the present study, the molecular and proteomic response of Pseudomonas fluorescens biofilm cultured on lettuce was investigated after ultrasound treatment at different intensity levels. The results show that the biofilm was efficiently removed after ultrasound treatment with intensity higher than 21.06 W/cm2. However, at an intensity of less than 18.42 W/cm2, P. fluorescens was stimulated by ultrasound leading to promoted bacterial growth, extracellular protease activity, extracellular polysaccharide secretion (EPS), and synthesis of acyl-homoserine lactones (AHLs) as quorum-sensing signaling molecules. The expression of biofilm-related genes, stress response, and dual quorum sensing system was upregulated during post-treatment ultrasound. Proteomic analysis showed that ultrasound activated proteins in the flagellar system, which led to changes in bacterial tendency; meanwhile, a large number of proteins in the dual-component system began to be regulated. ABC transporters accelerated the membrane transport of substances inside and outside the cell membrane and equalized the permeability conditions of the cell membrane. In addition, the expression of proteins related to DNA repair was upregulated, suggesting that bacteria repair damaged DNA after ultrasound exposure.


Asunto(s)
Lactuca , Pseudomonas fluorescens , Pseudomonas fluorescens/fisiología , Proteómica , Biopelículas , Percepción de Quorum
4.
J Sci Food Agric ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967243

RESUMEN

BACKGROUND: Mycotoxin contamination of food has been gaining increasing attention. Hidden mycotoxins that interact with biological macromolecules in food could make the detection of mycotoxins less accurate, potentially leading to the underestimation of the total exposure risk. Interactions of the mycotoxins alternariol (AOH) and alternariol monomethyl ether (AME) with high-molecular glutenin were explored in this study. RESULTS: The recovery rates of AOH and AME (1, 2, and 10 µg kg-1) in three types of grains (rice, corn, and wheat) were relatively low. Molecular dynamics (MD) simulations indicated that AOH and AME bound to glutenin spontaneously. Hydrogen bonds and π-π stacking were the primary interaction forces at the binding sites. Alternariol with one additional hydroxyl group exhibited stronger binding affinity to glutenin than AME when analyzing average local ionization energy. The average interaction energy between AOH and glutenin was -80.68 KJ mol-1, whereas that of AME was -67.11 KJ mol-1. CONCLUSION: This study revealed the mechanisms of the interactions between AOH (or AME) and high-molecular glutenin using MD and molecular docking. This could be useful in the development of effective methods to detect pollution levels. These results could also play an important role in the evaluation of the toxicological properties of bound altertoxins. © 2024 Society of Chemical Industry.

5.
Environ Geochem Health ; 46(8): 276, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958774

RESUMEN

The occurrence of microplastics (MPs) and organic pollutants (OPs) residues is commonly observed in diverse environmental settings, where their interactions can potentially alter the behavior, availability, and toxicity of OPs, thereby posing risks to ecosystems. Herein, we particularly emphasize the potential for bioaccumulation and the biomagnification effect of MPs in the presence of OPs within the food chain. Despite the ongoing influx of novel information, there exists a dearth of data concerning the destiny and consequences of MPs in the context of food pollution. Further endeavors are imperative to unravel the destiny and repercussions of MPs/OPs within food ecosystems and processing procedures, aiming to gain a deeper understanding of the joint effect on human health and food quality. Nevertheless, the adsorption and desorption behavior of coexisting pollutants can be significantly influenced by MPs forming biofilms within real-world environments, including temperature, pH, and food constituents. A considerable portion of MPs tend to accumulate in the epidermis of vegetables and fruits, thus necessitating further research to comprehend the potential ramifications of MPs on the infiltration behavior of OPs on agricultural product surfaces.


Asunto(s)
Cadena Alimentaria , Contaminación de Alimentos , Microplásticos , Humanos , Contaminación de Alimentos/análisis , Bioacumulación , Monitoreo del Ambiente
6.
Crit Rev Food Sci Nutr ; : 1-15, 2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37584269

RESUMEN

The extensive utilization of pesticides in agriculture has resulted in the presence of pesticide residues in food and feed, which poses a significant threat to human health. Various physical and chemical methods have been proposed to remove pesticides, but most of these methods are either costly or susceptible to secondary contamination. Consequently, the utilization of microorganisms, such as probiotics, for eliminating pesticides, has emerged as a promising alternative. Probiotics, including lactic acid bacteria, yeasts, and fungi, have demonstrated remarkable efficiency and convenience in eliminating pesticide residues from food or feed. To promote the application of probiotic decontamination, this review examines the current research status on the utilization of probiotics for pesticide reduction. The mechanisms involved in microbial decontamination are discussed, along with the toxicity and potential health risks of degradation products. Furthermore, the review explores strategies to enhance probiotic detoxification and outlines prospects for future development.

7.
Crit Rev Food Sci Nutr ; 63(27): 8808-8822, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35389275

RESUMEN

G-quadruplex (G4) is a very interesting DNA structure, commonly associated with cancer and its treatment. With flexible binding ability, G4 has been extended as a significant component in biosensors. On account of its simple operation, high sensitivity and low cost, G4-based biosensors have attracted considerable interest for the detection of food contaminants. In this review, research published in recent 5 years is collated from a principle perspective, that is target recognition and signal transduction. Contaminants with G4 binding capacity are illustrated, emerging G4-based biosensors including colorimetric, electrochemical and fluorescent sensors are also elaborated. The current review indicates that G4 has provided an efficient and effective solution for the rapid detection of food contaminants. A distinctive feature of G4 as recognition unit is the simple composition, but the selectivity is still unsatisfactory. As signal reporter, G4/hemin DNAzyme has not only achieved amplified signals, but also enabled visualized detection, which offers great potential for on-site measurement. With improved selectivity and visualized signal, the combination of aptamer and G4 seems to be an ideal strategy. This promising combination should be developed for the real-time monitor of multiple contaminants in food matrix.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , ADN Catalítico , G-Cuádruplex , ADN , ADN Catalítico/química , ADN Catalítico/metabolismo , Aptámeros de Nucleótidos/química
8.
Int J Mol Sci ; 24(9)2023 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-37175414

RESUMEN

Mancozeb, an antifungal typically used for the growth of fruits, has the characteristic of non-internal absorption, and has a risk of binding to the waxy components of fruits. This work investigated the interaction of pesticide molecules with the waxy layer on the grape surface and their effects on pesticide residues in grapes. The study observed significant changes in the compositions of the waxy layer on the grape surface after soaking in a mancozeb standard solution. The six substances-oleanolic acid, ursolic acid, lupeol, octacosanol, hexacosanal, and γ-sitosterol-with discernible content differences were chosen for molecular docking. Docking results were further visualized by an independent gradient model based on Hirshfeld partition (IGMH). Hydrogen bonds and van der Waals forces were found between mancozeb and the six waxy components. Moreover, the negative matrix effects caused by the presence or absence of wax for the determination of mancozeb were different through the QuEChERS-HPLC-MS method. Compared with the residue of mancozeb in grapes (5.97 mg/kg), the deposition of mancozeb in grapes after dewaxing was significantly lower (1.12 mg/kg), which further supports that mancozeb may interact with the wax layer compositions. This work not only provides insights into the study of the interaction between pesticides and small molecules but also provides theoretical guidelines for the investigation of the removal of pesticide residues on the surface of fruits.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Vitis , Vitis/química , Residuos de Plaguicidas/análisis , Ceras/análisis , Simulación del Acoplamiento Molecular , Plaguicidas/análisis , Frutas
9.
Molecules ; 28(10)2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37241867

RESUMEN

Rice, which is a major part of the daily diet, is becoming more and more contaminated by cadmium (Cd). This study combined low-intensity ultrasonic waves with the Lactobacillus plantarum fermentation method and optimized this technique by a single-factor and response surface experiment, aiming to solve the practical problems that the current Cd removal methods for rice cannot address, due to the fact that they require a long time (nearly 24 h), which prevents meeting the rice production demands. The described technique required a short time (10 h), and the highest Cd removal reached 67.05 ± 1.38%. Further analysis revealed that the maximum adsorption capacity of Lactobacillus plantarum for Cd increased by nearly 75%, and the equilibrium adsorption capacity increased by almost 30% after the ultrasonic intervention. Additionally, a sensory evaluation and other experiments proved that the properties of the rice noodles prepared from Cd-reduced rice obtained by ultrasound-assisted fermentation were comparable to those of traditional rice noodles, indicating that this method can be used in actual rice production.


Asunto(s)
Lactobacillus plantarum , Oryza , Contaminantes del Suelo , Cadmio/análisis , Fermentación , Manipulación de Alimentos/métodos , Contaminantes del Suelo/análisis , Suelo
10.
Gastroenterol Hepatol ; 46(7): 531-541, 2023.
Artículo en Inglés, Español | MEDLINE | ID: mdl-36584755

RESUMEN

AIMS: Nonalcoholic fatty liver disease (NAFLD) is a chronic liver disease that affects adipose function. This study aimed to explore the function of adipocytes-derived exosomal (ADEs) miR-122 in NAFLD. METHODS: A high-fat and high-fructose diet-induced rat model and a palmitic acid (PA)-induced in vitro model were established. The RNA level of miR-122 and Sirt1 was measured using qRT-PCR. The protein levels of exosome biomarkers, and lipogenesis, inflammation and fibrosis biomarkers were determined by western blotting. Cell viability and apoptosis were assessed using cell counting kit-8 and flow cytometry, respectively. Serum alanine aminotransferase, aspartate aminotransferase, total cholesterol, triglyceride levels were measured. Liver tissue damage was assessed using haematoxylin and eosin staining. The interaction between miR-122 and Sirt1 3'UTR was assessed using a luciferase reporter gene assay. RESULTS: ADEs exhibited abundant level of miR-122 and promoted lipogenesis, impaired hepatocyte survival, enhanced liver damage and increased serum lipid levels in vivo and in vitro. Inhibition of miR-122 in ADEs alleviated NAFLD progression, lipid and glucose metabolism, liver inflammation and fibrosis both in vivo and in vitro. miR-122 binds directly to the 3'UTR of Sirt1 to suppress its expression. Moreover, Sirt1 overexpression reversed the increase in cell apoptosis, glucose and lipid metabolism, liver inflammation and fibrosis induced by ADEs in vivo and in vitro. CONCLUSIONS: The ADEs miR-122 promotes the progression of NAFLD via modulating Sirt1 signalling in vivo and in vitro. The ADEs miR-122 may be a promising diagnostic biomarker and therapeutic target for NAFLD.


Asunto(s)
MicroARNs , Enfermedad del Hígado Graso no Alcohólico , Ratas , Animales , Enfermedad del Hígado Graso no Alcohólico/genética , Sirtuina 1/genética , Sirtuina 1/metabolismo , Sirtuina 1/uso terapéutico , Regiones no Traducidas 3' , MicroARNs/metabolismo , Fibrosis , Hígado/patología , Biomarcadores , Progresión de la Enfermedad , Cirrosis Hepática/patología , Lípidos
11.
J Food Sci Technol ; 60(1): 372-381, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36618067

RESUMEN

Erwinia carotovora and Pseudomonas fluorescens were two bacteria commonly caused the spoilage of vegetables through biofilm formation and secretion of extracellular enzymes. In this study, N-(3-oxohexanoyl)-L-homoserine lactone (3-oxo-C6-HSL) and N-Octanoyl-L-homoserine lactone (C8-HSL) were confirmed as acylated homoserine lactones (AHLs) signal molecule produced by E. carotovora and P. fluorescens, respectively. In addition, quorum sensing inhibitory (QSI) effects of hexanal on AHLs production were evaluated. Hexanal at 1/2 minimum inhibitory concentration (MIC) was achieved 76.27% inhibitory rate of 3-oxo-C6-HSL production in E. carotovora and a inhibitory rate of C8-HSL (60.78%) in P. fluorescens. The amount of biofilm formation and activity of extracellular enzymes treated with 1/2 MIC of hexanal were restored with different concentrations (10 ng/mL, 50 ng/mL, 100 ng/mL) of exogenous AHLs (P < 0.05), which verified QSI effect of hexanal on biofilm and extracellular enzymes were due to its inhibition on AHLs production. Molecular docking analysis showed that hexanal could interact with EcbI and PcoI protein to disrupt AHLs production. Furthermore, results showed that sub-MICs of hexanal could suppress expressions of ecbI and pcoI genes in AHL-mediated QS system of E. carotovora and P. fluorescens. This study provides theoretical support for the application of essential oils as QS inhibitors in the preservation of vegetables. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05624-9.

12.
Crit Rev Food Sci Nutr ; 62(7): 1740-1751, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33207954

RESUMEN

The problem of drug resistance of food borne pathogens is becoming more and more serious. Although traditional antimicrobial agents have good therapeutic effects on a variety of food borne pathogens, more effective antimicrobial agents are still needed to combat the development of drug-resistant food borne pathogens. Plant-based natural essential oils (EOs) are widely used because of their remarkable antimicrobial activity. A potential strategy to address food borne pathogens drug resistance is to use a combination of EOs and antimicrobial agents. Because EOs have multi-target inhibitory effects on microorganisms, combining them with drugs can enhance the activity of the drugs and avoid the emergence of food borne pathogens drug resistance. This paper introduces the main factors affecting the antibacterial activity of EOs and describes methods for evaluating their synergistic antibacterial effects. The possible mechanisms of action of EOs and the synergistic inhibitory effects on pathogens of EOs in combination with antimicrobial agents is described. In summary, the combined use of EOs and existing antimicrobial agents is a promising potential new antibacterial therapy.


Asunto(s)
Antiinfecciosos , Aceites Volátiles , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Sinergismo Farmacológico , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología
13.
J Appl Microbiol ; 133(4): 2122-2136, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35007388

RESUMEN

AIM: Hexanal and geraniol are essential oil components with anti-quorum sensing (QS) activity against Pseudomonas fluorescens. This study demonstrated that QS inhibition (QSI) efficacy of the hexanal and geraniol combination (HG) was significantly higher when compared to those of their mono-counterparts at the same concentration. METHODS AND RESULTS: Tests on P. fluorescens motility, biofilm formation, acyl-homoserine lactones' (AHLs) production, gene expression in vitro, and molecular docking in silico were conducted to evaluate the synergistic effect of hexanal and geraniol on QSI. HG mixture at 0.5 minimal inhibitory concentration (MIC) showed a strong synergistic inhibition of biofilm formation (51.8%), motility (60.13%), and extracellular protease activity (58.9%) of P. fluorescens. The synthesis of AHLs, e.g., C8 -HSL and C12 -HSL, was inhibited by hexanal, geraniol, and HG; both AHLs are responsible for regulating virulence factors in P. fluorescens. The expression of pcoI and gacA genes regulating AHL synthetase and sensor kinase was significantly down-regulated by HG (0.29 and 0.38-fold) at 0.5 MIC. Hexanal and HG showed significant inhibition of the expression of pcoR and gacS genes, which are responsible for AHL receptor protein and response regulation; however, geraniol failed to downregulate the two genes. Molecular docking in silico also supported these findings. Hexanal, which gets inserted into the minor groove of pcoI/pcoR DNA fragments, inhibits the expression of both the genes. Both hexanal (-31.487 kcal/mol) and geraniol (-25.716 kcal/mol) had a higher binding affinity with PcoI protein than the halogenated furanone C30 (-24.829 kcal/mol), which is a known competitor of AHLs. Similarly, hexanal and geraniol strongly bind to the PcoR protein also. CONCLUSIONS: It was found that HG at 0.5 MIC could effectively inhibit QS by suppressing the expression of pcoR/gacS and gacA/gacS genes and therefore, could inhibit the motility and biofilm formation of P. fluorescens. SIGNIFICANCE AND IMPACT OF THE STUDY: The present study indicated that HG at sub-MIC as QS inhibitor could be further developed as a new preservative of agri-food products.


Asunto(s)
Aceites Volátiles , Pseudomonas fluorescens , Monoterpenos Acíclicos , Acil-Butirolactonas/metabolismo , Aldehídos , Biopelículas , Ligasas/metabolismo , Simulación del Acoplamiento Molecular , Aceites Volátiles/metabolismo , Aceites Volátiles/farmacología , Péptido Hidrolasas/metabolismo , Pseudomonas fluorescens/fisiología , Factores de Virulencia/metabolismo
14.
J Sci Food Agric ; 102(14): 6612-6622, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35596658

RESUMEN

BACKGROUND: Ultrasound has the potential to increase microbial metabolic activity, so this study explored the stimulatory effect of ultrasound pre-treatment on the degradation of four common pesticides (fenitrothion, chlorpyrifos, profenofos, and dimethoate) during milk fermentation by Lactobacillus plantarum and its effect on yogurt quality. RESULTS: Appropriate ultrasound pretreatment significantly enhanced the growth of L. plantarum. The degradation percentages of pesticides increased by 19-38% under ultrasound treatment. Ultrasonic intensity, pulse duty cycle, and duration time were key factors affecting microbial growth and pesticide degradation. Under optimal ultrasonic pre-treatment conditions, the degradation rate constants of four pesticides were at least 3.4 times higher than those without sonication. In addition, such ultrasound pretreatment significantly shortened yogurt fermentation time, increased the water holding capacity, hardness and antioxidant activity of the yogurt, and improved the flavor quality of the yogurt. CONCLUSION: Ultrasonic pretreatment significantly accelerated the degradation of the four pesticides during yogurt fermentation. In addition, such ultrasound pretreatment increased the efficiency of yogurt making and improved the quality of yogurt in terms of water holding capacity, firmness, antioxidant activity, and flavor. These findings provide a basis for the application of ultrasound to the removal of pesticide residues and quality improvement of yogurt. © 2022 Society of Chemical Industry.


Asunto(s)
Cloropirifos , Residuos de Plaguicidas , Plaguicidas , Terapia por Ultrasonido , Animales , Antioxidantes/análisis , Cloropirifos/análisis , Dimetoato/análisis , Fenitrotión/análisis , Fenitrotión/metabolismo , Fermentación , Leche/química , Residuos de Plaguicidas/análisis , Plaguicidas/análisis , Agua/análisis , Yogur/análisis
15.
Compr Rev Food Sci Food Saf ; 21(5): 4402-4421, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36037152

RESUMEN

Drying is an important and influential process to prolong the shelf-life of food in the food industry. Recent studies have shown that cold plasma (CP) as an emerging drying pretreatment technology can improve drying performance, reduce drying energy consumption, and improve dried food quality. This paper comprehensively reviewed the mechanism of CP improving drying performance, related equipment, energy consumption, influencing factors, and impact on drying quality. This review also discusses the advantages and disadvantages and proposes possible challenges and suggestions for future research. Most studies indicated that CP pretreatment could improve the drying rate and quality and reduce the drying energy consumption. CP can promote moisture diffusion and improve drying efficiency by etching the surface and affecting the internal microstructure. In addition, CP can enhance the quality of dried products by reducing drying time and enzyme activity. Further research is needed to explore the drying mechanisms and equipment innovations to promote the application of CP in the food drying industry.


Asunto(s)
Gases em Plasma , Desecación , Calidad de los Alimentos
16.
Crit Rev Food Sci Nutr ; 61(9): 1545-1555, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32393047

RESUMEN

With the development in international food trade, there has been emerging risks in the food chain. Food contamination can be caused by several factors in a complex food chain. This articles provides a comprehensive review of known chemical contaminants from the production of raw materials to the consumption of food products as well as prevention and control measures. Specifically, this review discusses the following topics, raw material contamination caused by environmental pollution, endogenous food contamination caused by processing methods, and cold chain system challenges in food e-commerce.


Asunto(s)
Contaminación de Alimentos , Manipulación de Alimentos , Contaminación Ambiental , Alimentos , Contaminación de Alimentos/análisis
17.
Crit Rev Food Sci Nutr ; 61(21): 3555-3568, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32772549

RESUMEN

With the globalization of food and its complicated networking system, a wide range of food contaminants is introduced into the food system which may happen accidentally, intentionally, or naturally. This situation has made food safety a critical global concern nowadays and urged the need for effective technologies capable of dealing with the detection of food contaminants as efficiently as possible. Hence, Surface-enhanced Raman spectroscopy (SERS) has been taken as one of the primary choices for this case, due to its extremely high sensitivity, rapidity, and fingerprinting interpretation capabilities which account for its competency to detect a molecule up to a single level. Here in this paper, we present a comprehensive review of various SERS-based novel approaches applied for direct and indirect detection of single and multiple chemical and microbial contaminants in food, food products as well as water. The aim of this paper is to arouse the interest of researchers by addressing recent SERS-based, novel achievements and developments related to the investigation of hazardous chemical and microbial contaminants in edible foods and water. The target chemical and microbial contaminants are antibiotics, pesticides, food adulterants, Toxins, bacteria, and viruses. In this paper, different aspects of SERS-based reports have been addressed including synthesis and use of various forms of SERS nanostructures for the detection of a specific analyte, the coupling of SERS with other analytical tools such as chromatographic methods, combining analyte capture and recognition strategies such as molecularly imprinted polymers and aptasensor as well as using multivariate statistical analyses such as principal component analysis (PCA)to distinguish between results. In addition, we also report some strengths and limitations of SERS as well as future viewpoints concerning its application in food safety.


Asunto(s)
Nanoestructuras , Plaguicidas , Inocuidad de los Alimentos , Análisis de Componente Principal , Espectrometría Raman
18.
Artículo en Inglés | MEDLINE | ID: mdl-34129421

RESUMEN

Hg2+ toxicity is one of the most common chemical poisonings that occurs mainly from drinking polluted water. In the current work, Phycocyanin (PC) was exploited as a fluorescent sensor for sensitive and selective detection of Hg2+ in an aqueous system. PC-Hg2+ interaction was monitored using a spectro-fluorometer under different buffered solutions at pH values of 6,7,8,9, or 10 above the isoelectric point of PC (5.18). A remarkable decrease of PC fluorescence intensity was observed under Tris-buffer at pH 6 upon the addition of increasing Hg2+ concentrations (1-120 nM). Under the maintained experimental conditions, the current sensor showed a good linear relationship with R2 = 0.9971 and a limit of detection as low as 0.7 nM was achieved. In addition, a notable selectivity of Hg2+ over other nine heavy metals (Cu2+, Zn2+, Pb2+, Mg2+, Mn4+, Li+, Fe3+, Co2+, and Al3+) was achieved in the presence of 120 nM of each metal. Moreover, the current fluorescent detection assay was also tested in real samples of pond water, and recoveries as well as relative standard deviations within the acceptable limits were recorded.


Asunto(s)
Mercurio , Metales Pesados , Colorantes , Ficocianina , Agua
19.
Bull Environ Contam Toxicol ; 107(2): 221-227, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34129063

RESUMEN

At present, the detection of chlorothalonil is generally based on chromatography and immunoassay; both of which are time-consuming and costly. In this study, Surface-enhanced Raman Spectroscopy (SERS) has been successfully utilized in the detection of chlorothalonil coupled with photochemistry and meanwhile, gold nanoparticles were prepared to enhance the Raman signal. Two Raman peaks (2246 cm- 1 and 2140 cm- 1) of chlorothalonil were appeared after ultraviolet (UV) irradiation compared to the original solution. Chlorothalonil generated excited and weakened C≡N bonds in its structure by absorbing UV energy, thus leading to two kinds of corresponding peaks. These two kinds of peaks were both selected as analytical peaks in chlorothalonil detection. Different light sources and solvents were made different contributions to the final spectra. Chlorothalonil methanol solution under 302 nm wavelength irradiation was performed the best. The 2246 cm- 1 sharp peak represented to the normal C≡N bond appeared at first, which overall trend was significantly increased followed by a gradual decrease. The 2140 cm- 1 broad peak represented to the weakened C≡N bond appeared later, which overall trend was increased as the irradiation time passing by and then kept stable. Natural bond orbital (NBO) analysis indicates that the downshift of C≡N bond from 2246 cm- 1 to 2140 cm- 1 is due to the increase of electronic populations of π* orbital of C≡N bond transited from π orbital excited by UV irradiation. The positively charged C≡N bond had more chance to approach negatively charged gold nanoparticles. The detection limit of chlorothalonil was as low as 0.1 ppm in the standard solution. Orange peels spiked with chlorothalonil oil were also detected in this paper to confirm the practical operability of this method. The SERS method may be further developed as a rapid detection of pesticides that contains a triple bond by utilizing photochemistry.


Asunto(s)
Citrus sinensis , Nanopartículas del Metal , Oro , Nitrilos , Espectrometría Raman
20.
Crit Rev Food Sci Nutr ; 60(17): 2825-2836, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-30040433

RESUMEN

Consumers' pursuit to a healthy lifestyle has promoted people to develop new technologies that can prolong the shelf life of food without the use of preservatives. Compared with other types of preservation, edible microcapsules containing essential oils (EOs) are becoming more and more popular especially the starch microcapsules containing essential oil (EOs-starch microcapsules) because of their environmentally friendly, healthier characteristics and the ability to carry active ingredients. In addition, the EOs-starch microcapsules can also reduce the flavor influence and prolong the action time of essential oil on food through its slow release effect, which can promote the use of EOs in food. Understanding the different collocation of edible starch microcapsules and EOs and the related antibacterial mechanism will be more effective and targeted to promote the application of EOs in the real food system. The review focus on the contribution of EOs-starch microcapsules to prolong the shelf life of food products, (1) binding characteristics of EOs-starch microcapsules were analyzed, (2) systematically summarizing the main materials and methods for preparing the EOs-microcapsules, (3) specifically addressing the action mechanisms of EOs-starch microcapsules on microorganism, (4) discussing the applications of EOs-starch microcapsules in specific food.


Asunto(s)
Aceites Volátiles , Almidón , Cápsulas , Conservación de Alimentos , Conservantes de Alimentos , Humanos
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