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1.
Food Chem ; 460(Pt 2): 140521, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39083964

RESUMEN

Vitamin B is easily degraded by light and heat during storage, which results in nutritional loss of food. Whey protein is expected to protect vitamin B by forming complexes through secondary bonds. The properties of the complexes and protective effects of whey protein on vitamins B1, B2, B3 and B6 were characterized. The percentage losses of vitamin B were decreased by more than 60% with the protection of whey protein. FTIR, fluorescence spectroscopy, thermodynamic analysis and molecular docking were used to investigate the binding interaction between vitamin B and whey protein. Vitamin B quenched the intrinsic fluorescence of whey protein, mainly with a static nature (Kq > 2.0 × 1010 L/(mol·s)). The interactions between whey protein and vitamin B were mostly mediated by hydrogen bonds and van der Waals forces, as demonstrated by the thermodynamic parameters and molecular docking.


Asunto(s)
Enlace de Hidrógeno , Simulación del Acoplamiento Molecular , Termodinámica , Proteína de Suero de Leche , Proteína de Suero de Leche/química , Proteína de Suero de Leche/metabolismo , Unión Proteica , Espectrometría de Fluorescencia
2.
Food Chem ; 452: 139544, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38723571

RESUMEN

This study investigated the effects of high hydrostatic pressure (HHP) on the binding interactions of cyanindin-3-O-glucoside (C3G) to bovine serum albumin, human serum albumin (HSA), bovine lactoferrin, and ovotransferrin. Fluorescence quenching revealed that HHP reduced C3G-binding affinity to HSA, while having a largely unaffected role for the other proteins. Notably, pretreating HSA at 500 MPa significantly increased its dissociation constant with C3G from 24.7 to 34.3 µM. Spectroscopic techniques suggested that HSA underwent relatively pronounced tertiary structural alterations after HHP treatments. The C3G-HSA binding mechanisms under pressure were further analyzed through molecular dynamics simulation. The localized structural changes in HSA under pressure might weaken its interaction with C3G, particularly polar interactions such as hydrogen bonds and electrostatic forces, consequently leading to a decreased binding affinity. Overall, the importance of pressure-induced structural alterations in proteins influencing their binding with anthocyanins was highlighted, contributing to optimizing HHP processing for anthocyanin-based products.


Asunto(s)
Antocianinas , Presión Hidrostática , Unión Proteica , Antocianinas/química , Antocianinas/metabolismo , Humanos , Animales , Bovinos , Albúmina Sérica/química , Albúmina Sérica/metabolismo , Simulación de Dinámica Molecular
3.
Front Nutr ; 11: 1378884, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38725578

RESUMEN

Myofibrillar proteins are an important component of proteins. Flavor characteristics are the key attributes of food quality. The ability of proteins to bind flavor is one of their most fundamental functional properties. The dynamic balance of release and retention of volatile flavor compounds in protein-containing systems largely affects the sensory quality and consumer acceptability of foods. At present, research on flavor mainly focuses on the formation mechanism of flavor components, while there are few reports on the release and perception of flavor components. This review introduces the composition and structure of myofibrillar proteins, the classification of flavor substances, the physical binding and chemical adsorption of myofibrillar proteins and volatile flavor substances, as well as clarifies the regulation law of flavor substances from the viewpoint of endogenous flavor characteristics and exogenous environment factors, to provide a theoretical reference for the flavor regulation of meat products.

4.
Food Chem ; 448: 139063, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38579555

RESUMEN

The rice glutelin (RG), the separated retentate (RGFs) and filtrate (FGFs) fractions from total glutelin fibrils (TGFs) at pH 3.5 were used as carrier for curcumin in this test. The solubility and antioxidant activities of curcumin were improved after binding with protein and fibrils. Compared to other complexes, the RGFs-curcumin complex exhibited a highest curcumin solubility (48.05%) and a superior sustained release property, probably owing to the stable hydrogen bond between the surface groups of fibrils and hydroxyl groups of polyphenols. In addition, thermodynamic parameters revealed that the RG/TGFs/RGFs-curcumin complexes were stabilized by hydrogen bonds and van der Waals forces, whereas FGFs interacted with curcumin through specific electrostatic interaction. Besides, after interacting with curcumin, the fibrils gathered into coarsened and agglutinated fibrillar aggregates, relating to the increment of a-helix and ß-sheet structure. These results suggested that RGFs could be a good alternative for curcumin delivery in food industry.

5.
J Hazard Mater ; 471: 134351, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38653136

RESUMEN

Macrophyte rhizospheric dissolved organic matter (ROM) served as widespread abiotic components in aquatic ecosystems, and its effects on antibiotic residues and antibiotic resistance genes (ARGs) could not be ignored. However, specific influencing mechanisms for ROM on the fate of antibiotic residues and expression of ARGs still remained unclear. Herein, laboratory hydroponic experiments for water lettuce (Pistia stratiotes) were carried out to explore mutual interactions among ROM, sulfamethoxazole (SMX), bacterial community, and ARGs expression. Results showed ROM directly affect SMX concentrations through the binding process, while CO and N-H groups were main binding sites for ROM. Dynamic changes of ROM molecular composition diversified the DOM pool due to microbe-mediated oxidoreduction, with enrichment of heteroatoms (N, S, P) and decreased aromaticity. Microbial community analysis showed SMX pressure significantly stimulated the succession of bacterial structure in both bulk water and rhizospheric biofilms. Furthermore, network analysis further confirmed ROM bio-labile compositions as energy sources and electron shuttles directly influenced microbial structure, thereby facilitating proliferation of antibiotic resistant bacteria (Methylotenera, Sphingobium, Az spirillum) and ARGs (sul1, sul2, intl1). This investigation will provide scientific supports for the control of antibiotic residues and corresponding ARGs in aquatic ecosystems.


Asunto(s)
Antibacterianos , Sulfametoxazol , Antibacterianos/farmacología , Antibacterianos/química , Farmacorresistencia Microbiana/genética , Bacterias/genética , Bacterias/metabolismo , Genes Bacterianos , Rizosfera , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/química , Microbiota , Biopelículas
6.
Water Res ; 256: 121562, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38604064

RESUMEN

Halophenylacetamides (HPAcAms) have been identified as a new group of nitrogenous aromatic disinfection byproducts (DBPs) in drinking water, but the toxicity mechanisms associated with HPAcAms remain almost completely unknown. In this work, the cytotoxicity of HPAcAms in human hepatoma (HepG2) cells was evaluated, intracellular oxidative stress/damage levels were analyzed, their binding interactions with antioxidative enzyme were explored, and a quantitative structure-activity relationship (QSAR) model was established. Results indicated that the EC50 values of HPAcAms ranged from 2353 µM to 9780 µM, and the isomeric structure as well as the type and number of halogen substitutions could obviously induce the change in the cytotoxicity of HPAcAms. Upon exposure to 2-(3,4-dichlorophenyl)acetamide (3,4-DCPAcAm), various important biomarkers linked to oxidative stress and damage, such as reactive oxygen species, 8­hydroxy-2-deoxyguanosine, and cell apoptosis, exhibited a significant increase in a dose-dependent manner. Moreover, 3,4-DCPAcAm could directly bind with Cu/Zn-superoxide dismutase and induce the alterations in the structure and activity, and the formation of complexes was predominantly influenced by the van der Waals force and hydrogen bonding. The QSAR model supported that the nucleophilic reactivity as well as the molecular compactness might be highly important in their cytotoxicity mechanisms in HepG2 cells, and 2-(2,4-dibromophenyl)acetamide and 2-(3,4-dibromophenyl)acetamide deserved particular attention in future studies due to the relatively higher predicted cytotoxicity. This study provided the first comprehensive investigation on the cytotoxicity mechanisms of HPAcAm DBPs.


Asunto(s)
Desinfección , Agua Potable , Agua Potable/química , Humanos , Células Hep G2 , Relación Estructura-Actividad Cuantitativa , Acetamidas/toxicidad , Acetamidas/química , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/química , Estrés Oxidativo/efectos de los fármacos , Desinfectantes/toxicidad , Desinfectantes/química , Especies Reactivas de Oxígeno/metabolismo
7.
Int J Biol Macromol ; 264(Pt 1): 130535, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38432277

RESUMEN

This study investigated the molecular mechanism underlying the binding interaction between apigenin (API) and α-glucosidase (α-glu) by a combination of experimental techniques and computational simulation strategies. The spontaneously formation of stable API-α-glu complex was mainly driven by hydrogen bonds and hydrophobic forces, leading to a static fluorescence quenching of α-glu. The binding of API induced secondary structure and conformation changes of α-glu, decreasing the surface hydrophobicity of protein. Computational simulation results demonstrated that API could bind into the active cavity of α-glu via its interaction with active residues at the binding site. The important roles of key residues responsible for the binding stability and affinity between API and α-glu were further revealed by MM/PBSA results. In addition, it can be found that the entrance of active site tended to close after API binding as a result of its interaction with gate keeping residues. Furthermore, the structural basis for the binding interaction behavior of API was revealed and visualized by weak interaction analysis. The findings of our study revealed atomic-level mechanism of the interaction between API, which might shed light on the development of better inhibitors.


Asunto(s)
Apigenina , alfa-Glucosidasas , alfa-Glucosidasas/metabolismo , Inhibidores de Glicósido Hidrolasas/química , Simulación del Acoplamiento Molecular , Análisis Espectral , Sitios de Unión , Unión Proteica , Termodinámica
8.
Bioorg Chem ; 144: 107177, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38335756

RESUMEN

In order to find effective α-glucosidase inhibitors, a series of thiazolidine-2,4-dione derivatives (C1 âˆ¼ 36) were synthesized and evaluated for α-glucosidase inhibitory activity. Compared to positive control acarbose (IC50 = 654.35 ± 65.81 µM), all compounds (C1 âˆ¼ 36) showed stronger α-glucosidase inhibitory activity with IC50 values of 0.52 ± 0.06 âˆ¼ 9.31 ± 0.96 µM. Among them, C23 with the best anti-α-glucosidase activity was a reversible mixed-type inhibitor. Fluorescence quenching suggested the binding process of C23 with α-glucosidase in a static process. Fluorescence quenching, CD spectra, and 3D fluorescence spectra results also implied that the binding of C23 with α-glucosidase caused the conformational change of α-glucosidase to inhibit the activity. Molecular docking displayed the binding interaction of C23 with α-glucosidase. Compound C23 (8 âˆ¼ 64 µM) showed no cytotoxicity against LO2 and 293 cells. Moreover, oral administration of C23 (50 mg/kg) could reduce blood glucose and improve glucose tolerance in mice.


Asunto(s)
Inhibidores de Glicósido Hidrolasas , Hipoglucemiantes , Tiazolidinedionas , Ratones , Animales , Inhibidores de Glicósido Hidrolasas/química , Hipoglucemiantes/química , Estructura Molecular , Relación Estructura-Actividad , alfa-Glucosidasas/metabolismo , Simulación del Acoplamiento Molecular , Tiazolidinas
9.
J Oleo Sci ; 73(1): 113-119, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38171727

RESUMEN

Cluster of differentiation 36 (CD36) is a scavenger receptor expressed in various vertebrate cells that contains diverse ligands, including long-chain fatty acids. This receptor has recently been suggested as a captor of specific volatile odorants (e.g., aliphatic acetates) in the mammalian nasal epithelium. This study used a fluorescence-intensifying assay to produce the first evidence that lauric acid, an odorous fatty acid, directly binds to CD36. This expansion of the repertoire of volatile ligands supports potential applications for nasal CD36. Our present findings could promote future research aimed at understanding the mechanisms of fatty acid interactions with CD36.


Asunto(s)
Antígenos CD36 , Ácidos Grasos , Animales , Antígenos CD36/metabolismo , Fluorescencia , Odorantes , Ácidos Láuricos , Mamíferos/metabolismo
10.
J Hazard Mater ; 465: 133132, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38056269

RESUMEN

As highly toxic nitrogenous disinfection byproducts (DBPs), monohaloacetamides (monoHAcAms) generally exhibited a cytotoxic rank order of iodoacetamide ˃ bromoacetamide ˃ chloroacetamide. However, the mechanisms underlying the halogen-dependent cytotoxic pattern remain largely veiled as yet. In this work, oxidative stress/damage levels in monoHAcAm-treated Chinese hamster ovary cells were thoroughly analyzed, and binding interactions between monoHAcAms and antioxidative enzyme Cu/Zn-superoxide dismutase (Cu/Zn-SOD) were investigated by multiple spectroscopic techniques and molecular docking. Upon exposure to monoHAcAms, the intracellular levels of key biomarkers associated with oxidative stress/damage, including reactive oxygen species, malondialdehyde, lactate dehydrogenase, 8-hydroxy-2-deoxyguanosine, cell apoptosis, and G1 cell cycle arrest, were all significantly increased in a dose-response manner with the same halogen-dependent rank order as their cytotoxicity. Moreover, this rank order was also determined to be applicable to the monoHAcAm-induced alterations in the conformation, secondary structure, and activity of Cu/Zn-SOD, the microenvironment surrounding aromatic amino acid residues in Cu/Zn-SOD, as well as the predicted binding energy of SOD-monoHAcAm interactions. Our results revealed that the halogen-dependent cytotoxic pattern of monoHAcAms was attributed to their differential capacity to induce oxidative stress/damage and their interaction with antioxidative enzyme, which contribute to a better understanding of the halogenated DBP-induced toxicological mechanisms.


Asunto(s)
Desinfección , Halógenos , Animales , Cricetinae , Desinfección/métodos , Células CHO , Simulación del Acoplamiento Molecular , Cricetulus , Antioxidantes , Superóxido Dismutasa/metabolismo
11.
J Biomol Struct Dyn ; 42(3): 1170-1180, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37079322

RESUMEN

The study of the intermolecular binding interaction of small molecules with DNA can guide the rational drug design with greater efficacy and improved or more selective activity. In the current study, nintedanib's binding interaction with salmon sperm DNA (ssDNA) was thoroughly investigated using UV-vis spectrophotometry, spectrofluorimetry, ionic strength measurements, viscosity measurements, thermodynamics, molecular docking, and molecular dynamic simulation techniques under physiologically simulated conditions (pH 7.4). The obtained experimental results showed that nintedanib and ssDNA had an apparent binding interaction. Nintedanib's binding constant (Kb) with ssDNA, as determined using the Benesi-Hildebrand plot, was 7.9 × 104 M-1 at 298 K, indicating a moderate binding affinity. The primary binding contact forces were hydrophobic and hydrogen bonding interactions, as verified by the enthalpy and entropy changes (ΔH0 and ΔS0), which were - 16.25 kJ.mol-1 and 39.30 J mol-1 K-1, respectively. According to the results of UV-vis spectrophotometry, viscosity assays, and competitive binding interactions with ethidium bromide or rhodamine B, the binding mode of nintedanib to ssDNA was minor groove. Molecular docking and molecular dynamic simulation studies showed that nintedanib fitted into the B-DNA minor groove's AT-rich region with high stability. This study can contribute to further understanding of nintedanib's molecular mechanisms and pharmacological effects.


Asunto(s)
Indoles , Salmón , Masculino , Animales , Simulación del Acoplamiento Molecular , Salmón/metabolismo , Dicroismo Circular , Espectrometría de Fluorescencia/métodos , Espectrofotometría Ultravioleta , Semen/metabolismo , ADN/química , Termodinámica , Inhibidores de Proteínas Quinasas
12.
Expert Opin Ther Pat ; 33(10): 631-649, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37982191

RESUMEN

INTRODUCTION: Matrix metalloproteinases (MMPs) are strongly interlinked with the progression and mechanisms of several life-threatening diseases including cancer. Thus, novel MMP inhibitors (MMPIs) as promising drug candidates can be effective in combating these diseases. However, no MMPIs are marketed to date due to poor pharmacokinetics and lower selectivity. Therefore, this review was performed to study the newer MMPIs patented after the COVID-19 period for an updated perspective on MMPIs. AREAS COVERED: This review highlights patents related to MMPIs, and their therapeutic implications published between January 2021 and August 2023 available in the Google Patents, Patentscope, and Espacenet databases. EXPERT OPINION: Despite various MMP-related patents disclosed up to 2020, newer patent applications in the post-COVID-19 period decreased a lot. Besides major MMPs, other isoforms (i.e. MMP-3 and MMP-7) have gained attention recently for drug development. This may open up newer dimensions targeting these MMPs for therapeutic advancements. The isoform selectivity and bioavailability are major concerns for effective MMPI development. Thus, adopting theoretical approaches and experimental methodologies can unveil the development of novel MMPIs with improved pharmacokinetic profiles. Nevertheless, the involvement of MMPs in cancer, and the mechanisms of such MMPs in other diseases should be extensively studied for novel MMPI development.


Asunto(s)
Antineoplásicos , COVID-19 , Neoplasias , Humanos , Antineoplásicos/farmacología , Inhibidores de la Metaloproteinasa de la Matriz/farmacología , Metaloproteinasas de la Matriz/uso terapéutico , Patentes como Asunto , Neoplasias/tratamiento farmacológico
13.
Chem Biodivers ; 20(12): e202301217, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37870539

RESUMEN

The binding of pseudallecin A (PA), a potential antibiotic with strong inhibitory activities against Gram-positive Escherichia coli and Gram-negative Staphylococcus aureus, to human serum albumin (HSA) was explored. The interaction between them was assessed by multi-spectroscopic analysis, binding site competitive analysis, molecular docking and molecular dynamic simulation, showing the results as follows: PA effectively quenched the innate fluorescence of HSA by a static quenching process, formed a complex at a molar ratio of approximately 1 : 1 and performed an effective non-radiative energy transfer; the binding of PA to HSA was a spontaneous exothermic reaction driven by enthalpy with strong affinity and had a slight effect on the conformation of HSA; PA bound at site III of HSA and hydrogen bonds were the major binding forces to maintain the stability of the PA-HSA complex. Molecular dynamic simulation was performed to calculate the root mean square deviation (RMSD), root mean square fluctuation (RMSF) and radius of gyration (Rg) for this complex and effectively supported the spectroscopic outcome. These results meant that the delivery and distribution of PA as a water-insoluble molecule can be efficiently accomplished via HSA in human blood and, it has a good potential for future drug application and pharmacological development.


Asunto(s)
Simulación de Dinámica Molecular , Albúmina Sérica Humana , Humanos , Albúmina Sérica Humana/metabolismo , Simulación del Acoplamiento Molecular , Unión Proteica , Sitios de Unión , Termodinámica , Dicroismo Circular , Espectrometría de Fluorescencia
14.
J Mol Recognit ; 36(8): e3043, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37386810

RESUMEN

The in vitro interactions of homopterocarpin, a potent antioxidant and anti-ulcerative isoflavonoid, with human serum albumin (HSA) and human aldehyde dehydrogenase (hALDH) were explored using various spectroscopic methods, in silico and molecular dynamic (MD) studies. The result showed that homopterocarpin quenched the intrinsic fluorescences of HSA and hALDH. The interactions were entropically favorable, driven primarily by hydrophobic interactions. The proteins have one binding site for the isoflavonoid. This interaction  increased the proteins hydrodynamic radii by over 5% and caused a slight change in HSA surface hydrophobicity Homopterocarpin preferentially binds to HSA subdomain IB with a binding affinity of -10.1 kcal/mol before interaction stoke with hALDH (-8.4 kcal/mol). HSA-homopterocarpin complex attained pharmacokinetic-pharmacodynamics reversible equilibration time faster than ALDH-homopterocarpin. However, the probable and eventual therapeutic effect of homopterocarpin is the mixed inhibition ALDH activity having a Ki value of 20.74 µM. The MD results revealed the stabilization of the complex in HSA-homopterocarpin and ALDH-homopterocarpin from their respective spatial structures of the complex. The findings of this research will provide significant benefits in understanding the pharmacokinetics characteristics of homopterocarpin at the clinical level.


Asunto(s)
Aldehído Deshidrogenasa , Albúmina Sérica Humana , Humanos , Albúmina Sérica Humana/química , Unión Proteica , Aldehído Deshidrogenasa/metabolismo , Simulación del Acoplamiento Molecular , Termodinámica , Sitios de Unión , Espectrometría de Fluorescencia , Dicroismo Circular
15.
Int J Mol Sci ; 24(8)2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37108523

RESUMEN

Protein kinase p38γ is an attractive target against cancer because it plays a pivotal role in cancer cell proliferation by phosphorylating the retinoblastoma tumour suppressor protein. Therefore, inhibition of p38γ with active small molecules represents an attractive alternative for developing anti-cancer drugs. In this work, we present a rigorous and systematic virtual screening framework to identify potential p38γ inhibitors against cancer. We combined the use of machine learning-based quantitative structure activity relationship modelling with conventional computer-aided drug discovery techniques, namely molecular docking and ligand-based methods, to identify potential p38γ inhibitors. The hit compounds were filtered using negative design techniques and then assessed for their binding stability with p38γ through molecular dynamics simulations. To this end, we identified a promising compound that inhibits p38γ activity at nanomolar concentrations and hepatocellular carcinoma cell growth in vitro in the low micromolar range. This hit compound could serve as a potential scaffold for further development of a potent p38γ inhibitor against cancer.


Asunto(s)
Antineoplásicos , Simulación de Dinámica Molecular , Antineoplásicos/farmacología , Bioensayo , Descubrimiento de Drogas , Ligandos , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad Cuantitativa , Proteína Quinasa 12 Activada por Mitógenos/metabolismo
16.
Food Res Int ; 168: 112760, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37120211

RESUMEN

Tea processing steps affected the proximate composition, enzyme activity and bioactivity of coffee leaves; however, the effects of different tea processing steps on the volatiles, non-volatiles, color, and sensory characteristics of coffee leaves have yet been demonstrated. Here the dynamic changes of volatile and non-volatile compounds in different tea processing steps were investigated using HS-SPME/GC-MS and HPLC-Orbitrap-MS/MS, respectively. A total of 53 differential volatiles (alcohol, aldehyde, ester, hydrocarbon, ketone, oxygen heterocyclic compounds, phenol, and sulfur compounds) and 50 differential non-volatiles (xanthone, flavonoid, organic acid, amino acid, organic amine, alkaloid, aldehyde, and purine et al.) were identified in coffee leaves prepared from different processing steps. Kill-green, fermentation, and drying steps significantly influenced the volatiles; however, kill-green, rolling, and drying steps significantly affected the color of coffee leaves and their hot water infusion. The coffee leaf tea that was prepared without the kill-green process was found to have a more pleasant taste as compared to the tea that was prepared with the kill-green process. This can be attributed to the fact that the former contained lower levels of flavonoids, chlorogenic acid, and epicatechin, but had higher levels of floral, sweet, and rose-like aroma compounds. The binding interactions between the key differential volatile and non-volatile compounds and the olfactory and taste receptors were also investigated. The key differential volatiles, pentadecanal and methyl salicylate generate fresh and floral odors by activating olfactory receptors, OR5M3 and OR1G1, respectively. Epicatechin showed a high affinity to the bitter receptors, including T2R16, T2R14, and T2R46. Since the specific content of differential compounds in different samples varies greatly, the dose-effect and structure-function relationships of these key compounds and the molecular mechanism of the odor and taste of coffee leaf tea need to be further studied.


Asunto(s)
Camellia sinensis , Catequina , Coffea , Compuestos Orgánicos Volátiles , Aldehídos , Camellia sinensis/química , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Simulación del Acoplamiento Molecular , Microextracción en Fase Sólida , Espectrometría de Masas en Tándem , Gusto , Té/química , Compuestos Orgánicos Volátiles/análisis
17.
Molecules ; 28(7)2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-37049692

RESUMEN

A new series of ternary metal complexes, including Co(II), Ni(II), Cu(II), and Zn(II), were synthesized and characterized by elemental analysis and diverse spectroscopic methods. The complexes were synthesized from respective metal salts with Schiff's-base-containing amino acids, salicylaldehyde derivatives, and heterocyclic bases. The amino acids containing Schiff bases showed promising pharmacological properties upon complexation. Based on satisfactory elemental analyses and various spectroscopic techniques, these complexes revealed a distorted, square pyramidal geometry around metal ions. The molecular structures of the complexes were optimized by DFT calculations. Quantum calculations were performed with the density functional method for which the LACVP++ basis set was used to find the optimized molecular structure of the complexes. The metal complexes were subjected to an electrochemical investigation to determine the redox behavior and oxidation state of the metal ions. Furthermore, all complexes were utilized for catalytic assets of a multi-component Mannich reaction for the preparation of -amino carbonyl derivatives. The synthesized complexes were tested to determine their antibacterial activity against E. coli, K. pneumoniae, and S. aureus bacteria. To evaluate the cytotoxic effects of the Cu(II) complexes, lung cancer (A549), cervical cancer (HeLa), and breast cancer (MCF-7) cells compared to normal cells, cell lines such as human dermal fibroblasts (HDF) were used. Further, the docking study parameters were supported, for which it was observed that the metal complexes could be effective in anticancer applications.


Asunto(s)
Complejos de Coordinación , Humanos , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Bases de Schiff/farmacología , Bases de Schiff/química , Valina , Escherichia coli , Staphylococcus aureus , Metales/química , Antibacterianos/farmacología , Antibacterianos/química , Ligandos , Cobre/química
18.
Molecules ; 28(7)2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-37049792

RESUMEN

This work aimed to evaluate in vitro DNA binding mechanistically of cationic nitrosyl ruthenium complex [RuNOTSP]+ and its ligand (TSPH2) in detail, correlate the findings with cleavage activity, and draw conclusions about the impact of the metal center. Theoretical studies were performed for [RuNOTSP]+, TSPH2, and its anion TSP-2 using DFT/B3LYP theory to calculate optimized energy, binding energy, and chemical reactivity. Since nearly all medications function by attaching to a particular protein or DNA, the in vitro calf thymus DNA (ctDNA) binding studies of [RuNOTSP]+ and TSPH2 with ctDNA were examined mechanistically using a variety of biophysical techniques. Fluorescence experiments showed that both compounds effectively bind to ctDNA through intercalative/electrostatic interactions via the DNA helix's phosphate backbone. The intrinsic binding constants (Kb), (2.4 ± 0.2) × 105 M-1 ([RuNOTSP]+) and (1.9 ± 0.3) × 105 M-1 (TSPH2), as well as the enhancement dynamic constants (KD), (3.3 ± 0.3) × 104 M-1 ([RuNOTSP]+) and (2.6 ± 0.2) × 104 M-1 (TSPH2), reveal that [RuNOTSP]+ has a greater binding propensity for DNA compared to TSPH2. Stopped-flow investigations showed that both [RuNOTSP]+ and TSPH2 bind through two reversible steps: a fast second-order binding, followed by a slow first-order isomerization reaction via a static quenching mechanism. For the first and second steps of [RuNOTSP]+ and TSPH2, the detailed binding parameters were established. The total binding constants for [RuNOTSP]+ (Ka = 43.7 M-1, Kd = 2.3 × 10-2 M-1, ΔG0 = -36.6 kJ mol-1) and TSPH2 (Ka = 15.1 M-1, Kd = 66 × 10-2 M, ΔG0 = -19 kJ mol-1) revealed that the relative reactivity is approximately ([RuNOTSP]+)/(TSPH2) = 3/1. The significantly negative ΔG0 values are consistent with a spontaneous binding reaction to both [RuNOTSP]+ and TSPH2, with the former being very favorable. The findings showed that the Ru(II) center had an effect on the reaction rate but not on the mechanism and that the cationic [RuNOTSP]+ was a more highly effective DNA binder than the ligand TSPH2 via strong electrostatic interaction with the phosphate end of DNA. Because of its higher DNA binding affinity, cationic [RuNOTSP]+ demonstrated higher cleavage efficiency towards the minor groove of pBR322 DNA via the hydrolytic pathway than TSPH2, revealing the synergy effect of TSPH2 in the form of the complex. Furthermore, the mode of interaction of both compounds with ctDNA has also been supported by molecular docking.


Asunto(s)
Complejos de Coordinación , Rutenio , Simulación del Acoplamiento Molecular , Rutenio/química , Ligandos , Óxido Nítrico , ADN/química , Complejos de Coordinación/química , División del ADN
19.
J Hazard Mater ; 453: 131389, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37043854

RESUMEN

Comprehending the interactions between graphene oxide (GO) and enzymes is critical for understanding the toxicities of GO. In this study, the inherent interactions of GO with α-amylase as a typical enzyme, and the impacts of GO on the conformation and biological activities of α-amylase were systematically investigated. The results reveal that GO formed ground-state complex with α-amylase primarily via hydrogen bonding and van der Waals interactions, thus quenching the intrinsic fluorescence of the protein statically. Particularly, the strong interactions altered the microenvironment of tyrosine and tryptophan residues, caused rearrangement of polypeptide structure, and reduced the contents of α-helices and ß-sheets, thus changing the conformational structure of α-amylase. According to molecular docking results, GO binds with the amino acid residues (i.e., His299, Asp300, and His305) of α-amylase mainly through hydrogen bonding, which is in accordance with in vitro incubation experiments. As a consequence, the ability of α-amylase to catalyze starch hydrolysis into glucose was depressed by GO, suggesting that GO might cause dysfunction of α-amylase. This study discloses the intrinsic binding mechanisms of GO with α-amylase and provides novel insights into the adverse effects of GO as it enters organisms.


Asunto(s)
Grafito , alfa-Amilasas , alfa-Amilasas/metabolismo , Simulación del Acoplamiento Molecular , Conformación Molecular , Grafito/química
20.
J Food Sci Technol ; 60(4): 1376-1388, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36936118

RESUMEN

Curcumin, bioactive from turmeric Curcuma longa, has been known for its therapeutic properties. However, its lipophilic nature and poor bioavailability are the constraints to harnessing its properties. Encapsulation in nano-size helps to alleviate the constraints and enhance its biological properties due to its higher surface area. The study aims to encapsulate curcumin in a nanometer size range by solubilizing in lipid (milk fat) and using milk protein as a water-soluble carrier. The lipid:curcumin ratio (1:0.05, 1:0.1, 1:0.2, 1.5:0.1, 1.5:0.2, 2.0:0.1 and 2:0.2% (w/w)) produced nanoemulsion with droplets sizes 30-200 nm. The sample containing lipid: curcumin, as 1.0:0.05 resulted in an encapsulation efficiency of 92.6%, and its binding interaction with the carrier, was KD = 4.7 µM. A high solubility of curcumin in milk fat and digestion during in vitro lipolysis increased its bioaccessibility. A simulated gastro-intestinal in vitro studies showed that cumulative release percentage of nanoencapsulated curcumin was 60% at pH 7.4 compared to 0.8% of native curcumin. The anti-microbial property of nanoencapsulated curcumin was more potent than native curcumin against food pathogenic organisms such as S. aureus, B. cereus, E. coli, B. subtilis, P. aeruginosa, P. aeruginosa, C. violaceum. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05684-5.

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