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1.
Anal Chem ; 96(5): 2032-2040, 2024 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-38277772

RESUMEN

In situ profiling of single-nucleotide variations (SNVs) can elucidate drug-resistant genotypes with single-cell resolution. The capacity to directly "see" genetic information is crucial for investigating the relationship between mutated genes and phenotypes. Fluorescence in situ hybridization serves as a canonical tool for genetic imaging; however, it cannot detect subtle sequence alteration including SNVs. Herein, we develop an in situ Cas12a-based amplification refractory mutation system-PCR (ARMS-PCR) method that allows the visualization of SNVs related to quinolone resistance inside cells. The capacity of discriminating SNVs is enhanced by incorporating optimized mismatched bases in the allele-specific primers, thus allowing to specifically amplify quinolone-resistant related genes. After in situ ARMS-PCR, we employed a modified Cas12a/CRISPR RNA to tag the amplicon, thereby enabling specific binding of fluorophore-labeled DNA probes. The method allows to precisely quantify quinolone-resistant Salmonella enterica in the bacterial mixture. Utilizing this method, we investigated the survival competition capacity of quinolone-resistant and quinolone-sensitive bacteria toward antimicrobial peptides and indicated the enrichment of quinolone-resistant bacteria under colistin sulfate stress. The in situ Cas12a-based ARMS-PCR method holds the potential for profiling cellular phenotypes and gene regulation with single-nucleotide resolution at the single-cell level.


Asunto(s)
Quinolonas , Salmonella enterica , Sistemas CRISPR-Cas/genética , Alelos , Hibridación Fluorescente in Situ , Quinolonas/farmacología , Salmonella enterica/genética , Reacción en Cadena de la Polimerasa
2.
Environ Res ; 228: 115898, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37054837

RESUMEN

In this study, we report the synthesis of photoluminescent (PL) nitrogen (N) and sulfur (S) co-doped carbon dots (NS-CDs) from nitazoxanide and 3-mercaptopropionic acid as a precursors via a one-pot hydrothermal methods. N and S co-doped materials allows more active sites in the CDs surface resulting in an enhancement of their PL properties. NS-CDs show bright blue PL, excellent optical properties, good water solubility, and a high quantum yield (QY) of 32.1%. The as-prepared NS-CDs were confirmed by UV-Visible, photoluminescence, FTIR, XRD and TEM analysis. An optimized excitation at 345 nm, the NS-CDs exhibited strong PL emission at 423 nm with an average size of 3.53 ± 0.25 nm. Under optimized conditions, the NS-CDs PL probe shows high selectivity with Ag+/Hg2+ ions detected, while other cations no significant changes the PL signal. The PL intensity of NS-CDs linearly quenching and enhancement with Ag+ and Hg2+ ions from 0 to 50 × 10-6 M, with the detection limit of 2.15 × 10-6 M and 6.77 × 10-7 M (S/N = 3). More interestingly, as-synthesized NS-CDs shows a strong binding to Ag+/Hg2+ ions with the PL quenching and enhancement to precise and quantitative detection of Ag+/Hg2+ ions in living cells. The proposed system was effectively utilized for the sensing of Ag+/Hg2+ ions in real samples resulting in high sensitivity and good recoveries (98.4-109.7%).


Asunto(s)
Mercurio , Puntos Cuánticos , Carbono/química , Nitrógeno , Puntos Cuánticos/química , Azufre/química , Iones , Mercurio/análisis , Agua
3.
Molecules ; 28(19)2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37836676

RESUMEN

The purpose of this study was to develop a composite film composed of eugenol Pickering emulsion and pullulan-gelatin, and to evaluate its preservation effect on chilled beef. The prepared composite film was comprehensively evaluated in terms of the stability of emulsion, the physical properties of the film, and an analysis of freshness preservation for chilled beef. The emulsion size (296.0 ± 10.2 nm), polydispersity index (0.457 ± 0.039), and potential (20.1 ± 0.9 mV) proved the success of emulsion. At the same time, the films displayed good mechanical and barrier properties. The index of beef preservation also indicated that eugenol was a better active ingredient than clove essence oil, which led to the rise of potential of hydrogen, chroma and water content, and effectively inhibited microbial propagation, protein degradation and lipid oxidation. These results suggest that the prepared composites can be used as promising materials for chilled beef preservation.


Asunto(s)
Películas Comestibles , Eugenol , Animales , Bovinos , Eugenol/farmacología , Gelatina , Emulsiones , Aceite de Clavo
4.
Molecules ; 28(3)2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36771037

RESUMEN

Water contaminated with heavy metals constitutes an important threat. This threat is a real problem with a negative impact in some developing countries where untreated industrial effluents are used for irrigation. The present study examines heavy metals in wastewater-irrigated vegetables (apple gourd, spinach, cauliflower, sponge gourd, and coriander) water, and soil from Chenab Nagar, Chiniot, Pakistan. In particular, the metals quantified were cadmium (Cd), chromium (Cr), cobalt (Co), nickel (Ni), lead (Pb), and manganese (Mn). Among them, Cr and Co in crops irrigated -wastewater exceeded the levels recommended by the World Health Organization (WHO). In contrast, Ni, Cu, Pb, and Mn concentrations were in line with WHO standards. Compared with the limits established by the Food and Agriculture Organization of the United Nations (FAO), all the study vegetables presented higher (thus unsafe) concentrations of Cd (0.38 to 1.205 mg/Kg). There were also unsafe concentrations of Cr in coriander, sponge gourd, and cauliflower. Pb was found at an unsafe concentration (0.59 mg/Kg) in cauliflower. Conversely, Ni and Mn concentrations were below the maximum permissible limits by WHO, and FAO in all of the analyzed samples. The contamination load index (CLI) in soil, bioconcentration factor (BCF) in plants, daily intake of metals (DIM), and health risk index (HRI) have also been evaluated to estimate the potential risk to human health in that area. We have found an important risk of transitions of Pb, Cd, Cr, and Co from water/soil to the edible part of the plant. The highest HRI value associated with Cd (6.10-13.85) followed by Cr (1.25-7.67) for all vegetable samples presented them as high health risk metal contaminants. If the issue is not addressed, consumption of wastewater-irrigated vegetables will continue posing a health risk.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Humanos , Verduras , Aguas Residuales , Cadmio , Plomo , Monitoreo del Ambiente , Metales Pesados/toxicidad , Metales Pesados/análisis , Níquel , Cromo/toxicidad , Cobalto , Suelo , Manganeso , Agua , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Medición de Riesgo
5.
Anal Chem ; 94(48): 16953-16959, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36423327

RESUMEN

Lead contamination in the environment tends to enter the food chain and further into the human body, causing serious health issues. Herein, we proposed a Csm6-DNAzyme tandem assay (termed cDNAzyme) using CRISPR/Cas III-A Csm6 and GR-5 DNAzyme, enabling one-pot and sensitive detection of lead contamination. We found that Pb2+-activated GR-5 DNAzyme produced cleaved substrates that can serve as the activator of Csm6, and the Csm6-DNAzyme tandem improved the sensitivity for detecting Pb2+ by 6.1 times compared to the original GR-5 DNAzyme. Due to the high specificity of DNAzyme, the cDNAzyme assay can discriminate Pb2+ from other bivalent and trivalent interfering ions and allowed precise detection of Pb2+ in water and food samples. Particularly, the assay can achieve one-step, mix-and-read detection of Pb2+ at room temperature. We used the cDNAzyme assay to investigate the accumulation of lead in mice, and found that lead accumulated at higher levels in the colon and kidney compared to the liver, and most of the lead was excreted. The cDNAzyme assay is promising to serve as analytical tools for lead-associated environmental and biosafety issues.


Asunto(s)
Técnicas Biosensibles , ADN Catalítico , Ratones , Humanos , Animales , ADN Catalítico/metabolismo , Plomo , Bioacumulación , Iones , Límite de Detección
6.
World J Surg ; 46(8): 1849-1854, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35501607

RESUMEN

BACKGROUND: In view of importance for competency-based education (CBE), we undertook a self-study to elicit the available operative surgical workload and supervision for residents in the general surgical residency program at the teaching hospital in Karachi. METHODOLOGY: This was a cross-sectional study spanning a 5-year period between January 2015 and December 2019. The numbers of surgical residents during this period were identified. Five procedures were selected as core general surgical procedures: incision and drainage of superficial abscess, laparoscopic appendectomy, laparoscopic cholecystectomy, open inguinal hernia repair, and perianal procedures. Trends of the number of residents per year and the numbers of procedures per year were determined. The mean number of core procedures per eligible resident during their entire training was calculated to represent potential operative surgical experience and were benchmarked. The ratio of the average number of residents rotating in general surgery per year to the number of attending surgeons was determined as a measure of available supervision. RESULT: The mean total number of general surgical residents per year was 31.2 (range 28-35). The numbers of core general surgical procedures were consistent over the years of study. Potential exposure of eligible residents to each core procedure during their entire training was: 19.5 cases for incision and drainage of superficial abscess; 89 cases for laparoscopic appendectomy; 113.6 for inguinal hernia repair, 267.5 for laparoscopic cholecystectomy and 64.5 for perianal procedures. The average yearly residents to full-time attending surgeons' ratio was 2.5. The workload of core general surgical procedures at AKUH was higher than the Accreditation Council for Graduate Medical Education (ACGME) recommended volumes for operative surgical experience for residents in the US. CONCLUSION: This method of assessing the potential of a surgical program for transitioning to CBE appears practical and can be generalized.


Asunto(s)
Cirugía General , Hernia Inguinal , Internado y Residencia , Absceso , Competencia Clínica , Educación Basada en Competencias , Estudios Transversales , Educación de Postgrado en Medicina/métodos , Cirugía General/educación , Hernia Inguinal/cirugía , Hospitales de Enseñanza , Humanos , Pakistán , Atención Terciaria de Salud , Carga de Trabajo
7.
Molecules ; 27(3)2022 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-35164080

RESUMEN

Protein scarcity is the most vital cause of long-lasting diseases and even untimely deaths in some developing nations. The application of protein in food is advantageous from the point of view of non-toxicity, biocompatibility, and dietary benefits. This study aimed to determine the protein contents of the sprouts of Vigna radiates (mung beans), Lens culinaris (lentils), and Cicer arietinum (chickpeas) using the Kjeldahl and Lowry methods. The results obtained from the Kjeldahl method identified protein concentrations of 2.54, 2.63, and 2.19%, whereas the Lowry method results identified protein concentrations of 2.96%, 4.10%, and 1.6% in mung beans, lentils, and chickpeas, respectively. In both the methods, lentils were found to have the highest amount of protein followed by mung beans and chickpeas. Both the Kjeldahl and Lowry methods demonstrated good protein values and low variation in the protein amount in the analyzed samples. Furthermore, the methods had greater sensitivity and comparable experimental variability. The outcomes revealed that assays can be applied for protein analysis in legumes. In the context of a lack of suitable standard procedures for evaluating legumes' compositions, the present study is suitable for food control laboratories. In addition, the studied samples represent a significant source of protein and can be used to fulfil the daily requirements for protein intake and other food applications.


Asunto(s)
Cicer/química , Lens (Planta)/química , Proteínas de Plantas/análisis , Plantones/química , Vigna/química , Espectrofotometría
8.
Molecules ; 27(9)2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-35566332

RESUMEN

Panax notoginseng is an important functional health product, and has been used worldwide because of a wide range of pharmacological activities, of which the taproot is the main edible or medicinal part. However, the technologies for origin discrimination still need to be further studied. In this study, an ICP-MS/MS method for the accurate determination of 49 elements was established, whereby the instrumental detection limits (LODs) were between 0.0003 and 7.716 mg/kg, whereas the quantification limits (LOQs) were between 0.0011 and 25.7202 mg/kg, recovery of the method was in the range of 85.82% to 104.98%, and the relative standard deviations (RSDs) were lower than 10%. Based on the content of multi-element in P. notoginseng (total of 89 mixed samples), the discriminant models of origins and cultivation models were accurately determined by the neural networks (prediction accuracy was 0.9259 and area under ROC curve was 0.9750) and the support vector machine algorithm (both 1.0000), respectively. The discriminant models established in this study could be used to support transparency and traceability of supply chains of P. notoginseng and thus avoid the fraud of geographic identification.


Asunto(s)
Panax notoginseng , Panax notoginseng/química , Análisis Espectral , Espectrometría de Masas en Tándem
9.
Molecules ; 26(8)2021 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-33921808

RESUMEN

Heavy metals are the harmful elements, regarded as carcinogens. Nevertheless, owing to their physical and chemical properties, they are still used in the production of several commercial products. Utilization of such products increases the chance for the exposure of heavy metals, some of them are categorized as probable human carcinogens (Group 1) by the International Agency for Research on Cancer. Exposure of heavy metals to school children at early age can result severe life time health issues and high chance of emerging cancer. Thus, we have performed study relating to the presence of heavy metals in acrylic color paints commonly used by the school children. Acrylic paints of different colors were assayed for seven potential heavy metals manganese (Mn), cobalt (Co), nickel (Ni), zinc (Zn), arsenic (As), cadmium (Cd) and lead (Pb) using microwave digestion and iCAPQ inductively coupled plasma mass spectrometry (ICP-MS) system. The optimized method including paints digestion reagents nitric acid (HNO3, 65%, 5 mL) and hydrofluoric acid (HF, 40%, 2 mL) have offered excellent method performance with recovery values ranged between 99.33% and 105.67%. The elements were identified in all of the analyzed samples with concentrations ranged from 0.05 to 372.59 µg/g. Cd constitutes the lower percentage (0.05%), whereas Zn constitutes high ratio contribution which was tremendously high (68.33%). Besides, the paints contamination was also color specific, with considerably total heavy metal concentrations found in brunt umber (526.57 µg/g) while scarlet color (12.62 µg/g) contained lower amounts. The outcomes of our investigation highlight the necessity for guidelines addressing the heavy metals in acrylic color paints intended for the school children usage.


Asunto(s)
Metales Pesados/análisis , Pintura/análisis , Arsénico/análisis , Cadmio/análisis , Niño , Cobalto/análisis , Cobre/análisis , Monitoreo del Ambiente , Humanos , Níquel/análisis , Zinc/análisis
10.
Molecules ; 26(12)2021 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-34207072

RESUMEN

The aim of the research was to prepare low-cost adsorbents, including raw date pits and chemically treated date pits, and to apply these materials to investigate the adsorption behavior of Cr(III) and Cd(II) ions from wastewater. The prepared materials were characterized using SEM, FT-IR and BET surface analysis techniques for investigating the surface morphology, particle size, pore size and surface functionalities of the materials. A series of adsorption processes was conducted in a batch system and optimized by investigating various parameters such as solution pH, contact time, initial metal concentrations and adsorbent dosage. The optimum pH for achieving maximum adsorption capacity was found to be approximately 7.8. The determination of metal ions was conducted using atomic adsorption spectrometry. The experimental results were fitted using isotherm Langmuir and Freundlich equations, and maximum monolayer adsorption capacities for Cr(III) and Cd(II) at 323 K were 1428.5 and 1302.0 mg/g (treated majdool date pits adsorbent) and 1228.5 and 1182.0 mg/g (treated sagai date pits adsorbent), respectively. It was found that the adsorption capacity of H2O2-treated date pits was higher than that of untreated DP. Recovery studies showed maximal metal elution with 0.1 M HCl for all the adsorbents. An 83.3-88.2% and 81.8-86.8% drop in Cr(III) and Cd(II) adsorption, respectively, were found after the five regeneration cycles. The results showed that the Langmuir model gave slightly better results than the Freundlich model for the untreated and treated date pits. Hence, the results demonstrated that the prepared materials could be a low-cost and eco-friendly choice for the remediation of Cr(III) and Cd(II) contaminants from an aqueous solution.


Asunto(s)
Cadmio/química , Cromo/química , Metales Pesados/química , Phoeniceae/química , Semillas/química , Agua/química , Adsorción , Peróxido de Hidrógeno/química , Concentración de Iones de Hidrógeno , Iones/química , Cinética , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos
11.
Molecules ; 26(23)2021 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-34885659

RESUMEN

Aqueous fluorescent dispersions containing dyed acrylic-based copolymer nanoparticles possess significant credentials concerning green technology as compared to those prepared with the conventional vinyl-based monomers in textile and garment sectors; however, their essential textile fastness properties are yet to achieve. In the present work, a series of acrylic nanodispersions were synthesized by varying the moles ratio of benzyl methacrylate (BZMA), methyl methacrylate (MMA), and 2-hydroxypropyl methacrylate (HPMA) monomers. This was done to study their effect on dye aggregation and dyed polymer particles agglomeration. FT-IR spectral analysis showed the formation of polymer structures, while Malvern Analyzer, Transmission Electron Microscopy, and Scanning Electron Microscopy analysis suggested that the particles are spherical in shape and their size is less than 200 nm. The obtained nanodispersions were later applied on cotton fabrics for the evaluation of wash fastness and colour migration. Premier color scan spectrophotometer and zeta potential measurement studies suggested that colour migration of printed cotton fabrics increased with an increasing agglomeration of particles and it was also observed to increase with the moles ratio of MMA and zeta potentials.

12.
Langmuir ; 36(11): 2794-2801, 2020 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-32052969

RESUMEN

We successfully fabricated a conductive E-textile and color-coated E-textile by depositing multilayer Al2O3/TiO2 on a conductive E-textile through atomic layer deposition (ALD). Pt was deposited on an E-textile as a conductive layer via low-temperature ALD. The color of the coated conductive E-textile could be tuned to violet, green, or pink by simply varying the thickness of the Al2O3 and TiO2 layers. Both experimental and simulation results revealed that seven different colors can be obtained with single-layer TiO2 and multilayer Al2O3/TiO2, depending on the film thickness and their refractive indices. This method is highly effective for enhancing the fastness of structural color on conductive E-textiles. Furthermore, the mechanical properties and chemical stability of the color-coated E-textiles were investigated. The color-coated E-textiles could withstand acidic and basic solutions, with almost negligible changes in their morphology; this in turn indicates their excellent chemical stability. These switchable stable color-based conductive E-textiles can be used as a platform to directly integrate future wearable electronics in textiles.

13.
Mikrochim Acta ; 187(10): 580, 2020 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-32979097

RESUMEN

A 3D flexible domestic waste styrofoam is reported as a surface enhanced Raman scattering (SERS) substrate loaded with BiOCl-BiOBr@Pt/Au semiconductor-plasmonic composites. The hydrothermally prepared BiOCl-BiOBr nanocomposite is thoroughly characterized for its crystal structure using X-Ray diffraction, morphology through scanning electron microscopy, and electronic states of the elements using X-ray photoelectron spectroscopy. The alpha cypermethrin (ACM) is chosen as a model pesticide analyte for SERS investigation. The BiOCl-BiOBr@Pt/Au loaded foam substrate exhibited a high enhancement factor (106) and low limit of detection (10-10 M) upon SERS investigation. The unique architecture of the semiconductor-plasmonic composite enables an efficient charge transfer capability and plasmonic hotspots which aids in the enhancement of target analytes. In order to better demonstrate the versatility towards other pesticides, SERS detection of glyphosate and paraquat pesticides are also performed using the fabricated SERS substrate. The stability of the substrate has been investigated in detail for 30 days and the substrate was highly stable. The BiOCl-BiOBr@Pt/Au-based foam substrate also performed well in rapid real-time sensing of alpha cypermethrin on the kiwi fruit exocarp at lower level concentrations. Graphical abstract.


Asunto(s)
Nanopartículas del Metal/química , Plaguicidas/química , Poliestirenos/química , Humanos , Plata/química
14.
Food Chem ; 463(Pt 3): 141363, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39321654

RESUMEN

This study focuses on evaluating new methods for the green extraction of saponin compounds from Polygonatum cyrtonema Hua (PCH). This study utilized a combination of carboxylic acid-based natural deep eutectic solvents (NADES) and various extraction techniques including conventional heat reflux-, ultrasound-, and microwave-assisted extraction. The primary objectives were to assess total saponin yield, antioxidant capacity, and enzyme inhibition efficiency. Additionally, the solvents and extracts were evaluated for their antibacterial activity. Oil-in-water (O/W) emulsions of NADES extracts were also characterized and analyzed for stability. Results indicated that three NADES systems were effective in extracting saponins, with choline chloride and lactic acid (ChCl-LA) system being the most efficient. The ChCl:LA extract exhibited antimicrobial and antioxidant activities superior to conventional organic solvent extracts. Additionally, it demonstrated maximum inhibitory activity (IC50 values: 0.98 ± 0.03 and 1.46 ± 0.07 mg/mL, respectively) against α-glucosidase and α-amylase. The NADES extract as an aqueous phase significantly improved the stationarity of the O/W emulsion. Collectively, the study highlights the antimicrobial and technological advantages of NADES as a potential solvent for extracting saponin compounds from PCH.

15.
Food Chem X ; 24: 101842, 2024 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-39377084

RESUMEN

In this study, zein-pectin nanoparticles loaded with Wampee [Clausena lansium (Lour.) Skeels] (WEO) were developed. The particle size of the nanoparticles is 515.9 nm, polydispersity index is 0.4 and zeta potential is -39.3 mV. Subsequently, the ZWP was incorporated into sodium alginate (SA)-based film (ZWP-S). The films were then analyzed to determine their physical properties and thermal stability, and also to examine their microstructure and intermolecular forces using SEM, FTIR, and XRD techniques. Additionally, the films were evaluated for their antimicrobial and antioxidant activity, as well as their ability to sustain the release of WEO. Overall, the ZWP-S film conferred excellent functional properties, including UV barrier performance, mechanical properties (21 % increase in tensile strength), water sensitivity, stability, more compact structure, high antioxidant activity and long-lasting antimicrobial activity, surpassing those of the control film. Consequently, it was applied as a novel coating for preserving strawberries, rotting rate of strawberries was reduced by 43 % at 6d, yielding promising results in prolonging the freshness of the fruit.

17.
Food Res Int ; 184: 114270, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38609246

RESUMEN

This work set out to investigate how the physicochemical markers, volatiles, and metabolomic characteristics of mixed fermented the fermentation of Lycium barbarum and Polygonatum cyrtonema compound wine (LPCW) from S. cerevisine RW and D. hansenii AS2.45 changed over the course of fermentation. HS-SPME-GC-MS combined with non-targeted metabolomics was used to follow up and monitor the fermentation process of LPCW. In total, 43 volatile chemical substances, mostly alcohols, esters, acids, carbonyl compounds, etc., were discovered in LPCW. After 30 days of fermentation, phenylethyl alcohol had increased to 3045.83 g/mL, giving off a rose-like fresh scent. The biosynthesis of valine, leucine, and isoleucine as well as the metabolism of alanine, aspartic acid, and glutamic acid were the major routes that led to the identification of 1385 non-volatile components in total. This study offers a theoretical foundation for industrial development and advances our knowledge of the fundamental mechanism underlying flavor generation during LPCW fermentation.


Asunto(s)
Lycium , Polygonatum , Vino , Fermentación , Cromatografía de Gases y Espectrometría de Masas , Microextracción en Fase Sólida
18.
Food Chem X ; 22: 101271, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38495455

RESUMEN

Recent studies have witnessed that chemical modification can improve the physicochemical and functional properties of plants' polysaccharides. Herein, we modified the natural Lycium barbarum seed dreg polysaccharides (LBSDPs) by sulfation (S-LBSDPs), phosphorylation (P-LBSDPs), and carboxymethylation (C-LBSDPs), and evaluated the chemical composition and antioxidant activity of their derivatives. Natural polysaccharides and their derivatives exhibited typical polysaccharide absorption peaks and characteristic group absorption peaks in FT-IR spectra along with maximum UV absorption. After modification, the total sugar and protein contents of the derivatives were decreased, whereas the uronic acid content was increased. Among the three derivatives, sulfated polysaccharides displayed excellent thermal stability. S-LBSDP and P-LBSDP showed the highest ABTS radical scavenging and reducing power while S-LBSDPs and C-LBSDPs showed better DPPH radical scavenging effect, and P-LBSDPs showed considerable Fe2+ chelating ability. Our data indicate that chemical modifications can impart a positive effect on the antioxidant potential of plant-derived polysaccharides.

19.
Food Chem X ; 22: 101270, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38495459

RESUMEN

Lycium barbarum seed dregs (LBSDs) were used for carboxymethyl modification, resulting in three degree of substitution samples (DS). Based on the substitution degree, samples were designated as low degree of substitution insoluble dietary fiber (L-IDF), medium degree of substitution insoluble dietary fiber (M-IDF) and high degree of substitution insoluble dietary fiber (H-IDF). Physicochemical and functional properties of IDFs were examined in relation to carboxymethylation degree. Infrared Fourier transform spectroscopy (FT-IR) confirmed the carboxymethyl group. According to the results, IDF, L-IDF, M-IDF, and H-IDF acquired higher enthalpy changes, and their thermal stability improved significantly. A higher DS resulted in an increase in hydration properties such as water retention capacity and water swelling capacity, as well as functional properties such as glucose adsorption capacity, nitrite ion adsorption capacity, and cholesterol adsorption capacity. As a result, carboxymethylation could effectively enhance the biological properties of L. barbarum seed dreg insoluble dietary fiber (LBSDIDF).

20.
Int J Biol Macromol ; 280(Pt 2): 135503, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39304045

RESUMEN

Thermal processing of meat leads to the development of Maillard's reaction intermediates, and carcinogenic toxicants. For the first time, the effectiveness of three (HX-12A, HX-12B and HX-12C) antimicrobial peptides (AMPs) against the formation of heterocyclic amines (HAs) in chemical and meat model systems. The results showed that AMPs especially 12A and 12C have strong metal chelation potential (48 and 40% at 1 mg/ml) and antioxidant activity (35 and 25% at 1 mg/ml), respectively, which were endorsed by their secondary structure (FTIR analysis) in terms of high ß-sheets (1628 cm-1 and 1672 cm-1) in those AMPs. UPLC-MS analysis revealed that 12A and 12C were the most capable AMPs in MeIQx and PhIP-producing chemical models, respectively, whereas 12B promoted the HAs formation even higher than control. In particular, 12C AMP significantly (P < 0.05) decreased the most abundant carcinogenic HAs (PhIP) up to 90% at 9 mg/100 g of fresh meat, whereas 12A inhibited up to 80% of mutagenic HAs at same level compared to control and 12B. Low Field Nuclear Magnetic Resonance (LF-NMR) test showed that inhibitory effect of 12A and 12C was mediated by means of retaining water (lower T22 and T23 relaxation time) inside the macromolecules. This favorable effect was also evidenced by significantly enhanced tryptophan fluorescent intensity. Finally, based on correlation and principle component analysis, the mechanism of action has been proposed. These outcomes recommend that 12A and 12C are potential AMPs for the attenuation of HAs in thermally processed meat-based products.

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