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1.
Anal Chem ; 96(5): 2032-2040, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38277772

RESUMO

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.


Assuntos
Quinolonas , Salmonella enterica , Sistemas CRISPR-Cas/genética , Alelos , Hibridização in Situ Fluorescente , Quinolonas/farmacologia , Salmonella enterica/genética , Reação em Cadeia da Polimerase
2.
Environ Res ; 228: 115898, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37054837

RESUMO

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%).


Assuntos
Mercúrio , Pontos Quânticos , Carbono/química , Nitrogênio , Pontos Quânticos/química , Enxofre/química , Íons , Mercúrio/análise , Água
3.
Molecules ; 28(19)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37836676

RESUMO

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.


Assuntos
Filmes Comestíveis , Eugenol , Animais , Bovinos , Eugenol/farmacologia , Gelatina , Emulsões , Óleo de Cravo
4.
Molecules ; 28(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36771037

RESUMO

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.


Assuntos
Metais Pesados , Poluentes do Solo , Humanos , Verduras , Águas Residuárias , Cádmio , Chumbo , Monitoramento Ambiental , Metais Pesados/toxicidade , Metais Pesados/análise , Níquel , Cromo/toxicidade , Cobalto , Solo , Manganês , Água , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Medição de Risco
5.
Anal Chem ; 94(48): 16953-16959, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36423327

RESUMO

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.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Camundongos , Humanos , Animais , DNA Catalítico/metabolismo , Chumbo , Bioacumulação , Íons , Limite de Detecção
6.
World J Surg ; 46(8): 1849-1854, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35501607

RESUMO

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.


Assuntos
Cirurgia Geral , Hérnia Inguinal , Internato e Residência , Abscesso , Competência Clínica , Educação Baseada em Competências , Estudos Transversais , Educação de Pós-Graduação em Medicina/métodos , Cirurgia Geral/educação , Hérnia Inguinal/cirurgia , Hospitais de Ensino , Humanos , Paquistão , Atenção Terciária à Saúde , Carga de Trabalho
7.
Molecules ; 27(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35164080

RESUMO

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.


Assuntos
Cicer/química , Lens (Planta)/química , Proteínas de Plantas/análise , Plântula/química , Vigna/química , Espectrofotometria
8.
Molecules ; 27(9)2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35566332

RESUMO

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.


Assuntos
Panax notoginseng , Panax notoginseng/química , Análise Espectral , Espectrometria de Massas em Tandem
9.
Molecules ; 26(8)2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33921808

RESUMO

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.


Assuntos
Metais Pesados/análise , Pintura/análise , Arsênio/análise , Cádmio/análise , Criança , Cobalto/análise , Cobre/análise , Monitoramento Ambiental , Humanos , Níquel/análise , Zinco/análise
10.
Molecules ; 26(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207072

RESUMO

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.


Assuntos
Cádmio/química , Cromo/química , Metais Pesados/química , Phoeniceae/química , Sementes/química , Água/química , Adsorção , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Íons/química , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Águas Residuárias/química , Poluentes Químicos da Água/química , Purificação da Água/métodos
11.
Molecules ; 26(23)2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34885659

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-32052969

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-32979097

RESUMO

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.


Assuntos
Nanopartículas Metálicas/química , Praguicidas/química , Poliestirenos/química , Humanos , Prata/química
14.
Carbohydr Polym ; 330: 121764, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38368079

RESUMO

The rheological properties of a substance depend greatly on its morphology, and rod-shaped cellulose nanocrystals (RCNCs) and cellulose nanofibrils (CNFs) have been extensively studied for their rheological properties. Nevertheless, the rheological properties of disc-shaped cellulose nanocrystals (DCNCs) with crystalline allomorph II derived from mercerized cellulose remain unknown yet. This work investigated the DCNCs' rheological properties in depth using steady-shear and oscillation measurements. At the same concentration, DCNC's suspension viscosity is lower than that of RCNC; RCNC has an instinct viscosity of 258.2, while DCNC has 187.9. Comparing RCNC suspensions with cellulose nanorods, DCNC has a lower aspect ratio and exhibits a distinct steady shear behavior. Under polarized film, DCNC suspension cannot self-assemble into chiral or liquid crystal phases, and with increasing concentrations, the system transitions from an isotropic phase to a gel phase. Oscillation sweeps demonstrate that the gel transition occurs at 7 %-8 %. Based on thixotropic recovery sweep outcomes, the high-stress oscillations enhance the network structure of DCNC suspensions, which is significantly different from that of RCNC suspensions. Results demonstrate the unique properties of DCNC, highlighting its application as a rheological modifier.

15.
Food Chem ; 451: 139441, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38678656

RESUMO

The utilization of agroindustrial wastes to enrich food protein resources and the exploration of their broader applications are crucial for addressing the food crisis and achieving sustainable development goals. In this study, reeling wastewater-derived sericin was hydrolyzed using papain and trypsin to prepare sericin peptide (SRP) and was used as an antihardening ingredient of high-protein nutrition bars (HPNBs). The mechanism of the antihardening effect of SRP was elucidated by investigating the content of advanced glycation end products and protein oxidation products (carbonyl and free sulfhydryl), and the molecular weight change of HPNBs during storage before and after the addition of SRP. Our results confirmed the fortification of HPNBs with SRP, which is beneficial for the promotion and expansion of sericin applications in the food industry, with positive implications for the rational utilization of protein resources and the enrichment of food protein sources.


Assuntos
Peptídeos , Sericinas , Águas Residuárias , Sericinas/química , Águas Residuárias/química , Peptídeos/química , Armazenamento de Alimentos , Proteínas Alimentares/metabolismo , Proteínas Alimentares/química
16.
Food Chem X ; 22: 101497, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38840725

RESUMO

The demand for crayfish surimi products has grown recently due to its high protein content. This study examined the effects of varying κ-carrageenan (CAR) and crayfish surimi (CSM) concentrations on the gelling properties of CAR-CSM composite gel and its intrinsic formation process. Our findings demonstrated that with the increasing concentration of carrageenan, the quality of CAR-CSM exhibited rising trend followed by subsequently fall. Based on the textural qualities, the highest quality CAR-CSM was achieved at 0.3% carrageenan addition. With the exception of chewiness, and the cooking loss of the gel system was 1.62%, whiteness was 82.35%, and the percentage of ß-sheets increased to 57.18%. Further increase in CAR (0.4-0.5%) addition resulted in internal build-up of LCAR-CSM, conversion of intermolecular forces into disulfide bonds and gel breakage. This study exudes timely recommendations for extending the CAR application for the continuous development of crayfish surimi and its derivatives and its overall economic worth.

17.
Int J Biol Macromol ; 258(Pt 2): 128936, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38143058

RESUMO

The properties of cellulose nanocrystals with allomorph II (CNC-II) vary with the sources and the treatments received. In this work, the influences of hydrolysis time, temperature, and the applied acid concentration on the crystal size of CNC-II were investigated by the surface response experimental design. The results showed that temperature was the most significant factor affecting the crystal size of CNC-II during hydrolysis from mercerized cellulose. Then the morphology and colloidal properties of CNC-II were revealed by dynamic laser scattering (DLS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), etc. XRD results indicated that CNC-II had slightly lower crystallinity (80.89 % vs 82.7 %) and larger crystallite size (5.21 vs. 5.13 nm) than CNC-I. TEM and AFM results showed that the morphology of CNC-II were disc-like and rod-like particles, with an average diameter of 14.6 ± 4.7 nm (TEM) and a thickness of 4- 8 nm (AFM). TG and XPS revealed the reduced thermal stability was due to the introduced sulfate groups in CNC-II during hydrolysis. This investigation has addressed the features of CNC-II derived from mercerized cellulose, and it would be promising in fabricating advanced materials.


Assuntos
Celulose , Nanopartículas , Hidrólise , Celulose/química , Nanopartículas/química , Temperatura
18.
Food Res Int ; 184: 114270, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38609246

RESUMO

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.


Assuntos
Lycium , Polygonatum , Vinho , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Sólida
19.
Food Chem ; 451: 139521, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38703735

RESUMO

This study explored the use of ionic liquid-ultrasound (ILU)-assisted extraction to enhance the extraction rate of Platycodon grandiflorum saponins (PGSs), and the content, extraction mechanism, antioxidant activity, whitening, and antiaging activity of PGSs prepared using ILU, ultrasound-water, thermal reflux-ethanol, and cellulase hydrolysis were compared. The ILU method particularly disrupted the cell wall, improved PGS extraction efficiency, and yielded a high total saponin content of 1.45 ± 0.02 mg/g. Five monomeric saponins were identified, with platycodin D being the most abundant at 1.357 mg/g. PGSs displayed excellent in vitro antioxidant activity and exhibited inhibitory effects on tyrosinase, elastase, and hyaluronidase. The results suggest that PGSs may have broad antioxidant, skin-whitening, and antiaging potential to a large extent. Overall, this study provided valuable insights into the extraction, identification, and bioactivities of PGSs, which could serve as a reference for future development and application of these compounds in the functional foods industry.


Assuntos
Antioxidantes , Líquidos Iônicos , Extratos Vegetais , Platycodon , Saponinas , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Saponinas/farmacologia , Saponinas/química , Saponinas/isolamento & purificação , Platycodon/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/isolamento & purificação , Líquidos Iônicos/química , Envelhecimento da Pele/efeitos dos fármacos , Humanos , Ondas Ultrassônicas
20.
Food Chem X ; 22: 101271, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38495455

RESUMO

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.

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