Interaction studies of copper complex containing food additive carmoisine dye with human serum albumin (HSA): Spectroscopic investigations

Abstract

In this study, the interaction between human serum albumin (HSA) and a copper complex of carmoisine dye; [Cu(carmoisine) (H O) ], was studied in vitro using multi-spectroscopic methods. It was found that the intrinsic fluorescence of HSA was quenched by the addition of the [Cu(carmoisine) (H O) ] complex and the quenching mechanism was considered as static quenching by formation of a [Cu(carmoisine) (H O) ]-HSA complex. The binding constant was about 10 M at room temperature. The values of the calculated thermodynamic parameters (ΔH < 0 and ΔS > 0) suggested that both hydrogen bonds and the hydrophobic interactions were involved in the binding process. The site marker competitive experiments revealed that the binding of [Cu(carmoisine) (H O) ] to HSA primarily occurred in subdomain IIIA (site II) of HSA. The results of circular dichroism (CD) and UV-vis spectroscopy showed that the micro-environment of amino acid residues and the conformation of HSA were changed after addition of the [Cu(carmoisine) (H O) ] complex. Finally, the binding of the [Cu(carmoisine) (H O) ] complex to HSA was modelled by a molecular docking method. Excellent agreement was obtained between the experimental and theoretical results with respect to the binding forces and binding constant.

Esterase activity and conformational changes of bovine serum albumin toward interaction with mephedrone: Spectroscopic and computational studies

“…The values of ∆ H , ∆ S , and ∆ G for the interaction between 4MMC and BSA were listed in Table . From the table, the negative value of ∆ H and the positive value of ∆ S indicate that the formation of 4MMC‐BSA complex is driven by exothermic process, which involves the hydrophobic interaction with hydrogen bonding, playing a major role in the 4MMC‐BSA binding interaction . Further, the negative value of ∆G suggested that the interaction process is spontaneous.…”

Multi‐Spectroscopic and Theoretical Analyses of Human Serum Albumin Binding to a Water‐Soluble Zinc(II) Complex including β‐Amino Alcohol

“…CD technique is employed for studying the secondary structure of polypeptides and proteins in biological chemistry [43] . Commonly, far UV‐vis CD spectra (from 200 nm to 260 nm) reveal the secondary structure of the albumin protein [44] .…”

“…Commonly, far UV‐vis CD spectra (from 200 nm to 260 nm) reveal the secondary structure of the albumin protein [44] . The advent of two negative signals at 208 and 222 nm is the characteristic of the albumin α‐helical form, which is caused by charge transition (n→π*) in the covalent peptide bond of the α‐helix structure [43] . The serum protein CD spectra were taken before and after interacting with the zinc(II) complex to investigate the alterations in the secondary form of HSA and to acquire more specific information regarding it [45] .…”

“…[44] The advent of two negative signals at 208 and 222 nm is the characteristic of the albumin α-helical form, which is caused by charge transition (n!π*) in the covalent peptide bond of the α-helix structure. [43] The serum protein CD spectra were taken before and after interacting with the zinc(II) complex to investigate the alterations in the secondary form of HSA and to acquire more specific information regarding it. [45] The α-helical content of free albumin and albumin involved in the binding was assessed by MRE (mean residue ellipticity in deg cm 2 dmol À 1 ) amounts at 222 nm, which is displayed as the equation ( 9):…”

Caracterização De Corantes Para Elaboração De Cerejas Candeada: Eritrosina Versus Vermelho Gardenia

“…Estos últimos se continúan usando dado que poseen tres características muy interesantes: producción muy barata, tinte muy fuerte y una buena estabilidad química (Downham y Collins, 2000;Oreopoulou et al, 2009). No obstante, los colorantes sintéticos, si bien son muy versátiles en la industria alimentaria se han hallado en varios estudios que presentan una correlación positiva entre el consumo de los mismos y diversas alteraciones en la salud como: la hiperactividad (Bateman et al, 2004;McCann et al, 2007;Oplatowska-Stachowiak y Elliott, 2015), los defectos en el ADN (Khan et al, 2020), las reacciones alérgicas dermatológicas (Bateman et al, 2004;Panachiyil et al, 2019), la interacción con proteínas (Basu Y Suresh Kumar, 2015; Shahabadi et al, 2017;Wang et al, 2019) (Wopara et al, 2021).…”