Polyphenols redirects the self-assembly of serum albumin into hybrid nanostructures

Mechanistic insight into association of lysozyme, serum albumin, and insulin with aloin: Thermodynamic and conformational analysis

Lysozyme, serum albumin, and insulin carry out essential functions in the living systems. The properties and functions of these proteins may be positively impacted in association with Aloe vera, which is known to have usefulness as dietary supplement and clinical conditions. In this work, the conformational changes in these proteins have been analysed as a result of interaction with aloin, which has a long history of use in traditional health management. A combination of circular dichroism spectroscopy, fluorescence spectroscopy, and isothermal titration calorimetry have been used in analysing the associated thermodynamic signatures and structural changes. It is observed that lysozyme, and bovine serum albumin showed weak binding behaviour with aloin at molar ratio of (1:1), which is found to be entropically driven at first binding site while enthalpically driven at second binding site. Similarly for insulin also, the interaction of aloin increased with increase in its concentration and the binding of ligand at first and second site is entropically and enthalpically driven, respectively. These three proteins offer hydrophobic and hydrophilic functionalities for establishing intermolecular interactions with aloin. Differential scanning calorimetry and circular dichroism spectroscopy have provided mechanistic details on tertiary structural changes in these proteins as a result of interactions. The results offer valuable insights into molecular mechanism of conformational changes in these proteins and hence their properties in association with aloin, thereby, having biological implications related to health and food industry.

Fabrication of Robust Superhydrophobic Polyester Fabrics with Photothermal Conversion and Oil-Water Separation Performance through Deposition of Natural Polyphenols

Superhydrophobic polyester (PET) fabrics were created by increasing fabric surface roughness and decreasing surface energy through interactions between natural polyphenols, ferrous sulfate heptahydrate, and hexadecyltrimethoxysilane. The superhydrophobic fabric can be obtained with different natural polyphenols, including tannic acid, ferulic acid, gallic acid, guaiacol, and caffeic acid. Durability tests were carried out on the superhydrophobic PET fabric, investigating resistance to washing, rubbing, UV aging, acids, alkalis, and organic reagents. The results demonstrate the stability and versatility of modified PET in complex environments. The modified superhydrophobic PET fabric exhibited exceptional oil-water separation and self-cleaning properties, exhibiting a water contact angle of 161.3° and a sliding angle of 4°. In addition, the modified fabric demonstrated a remarkable photothermal conversion efficiency, with the surface temperature increasing from 29.1 to 72 °C in 300 s, and it maintained a degree of photothermal conversion capability even upon completion of four cycles. This study offers novel perspectives on extending the utilization of natural polyphenols for constructing durable, robust, and multifunctional superhydrophobic fabrics.

Comparative Evaluation of the Antiglycation and Anti-α-Glucosidase Activities of Baicalein, Baicalin (Baicalein 7-O-Glucuronide) and the Antidiabetic Drug Metformin

The discovery of new oral antidiabetic drugs remains a priority in medicine. This research aimed to evaluate the activity of the flavonoid baicalein and its natural glucuronide baicalin, compared to the antidiabetic drug metformin, as potential antiglycation, anti–radical, and anti-α–glucosidase agents, in order to assess their potential role in counteracting hyperglycemia-induced tissue damage. The study considered: (i) the BSA assay, to detect the formation of advanced glycation end products (AGEs), (ii) the GK peptide–ribose assay, which evaluates the cross–linking between the peptide and ribose, and (iii) the carbonyl content assay to detect the total carbonyl content, as a biomarker of tissue damage. In addition, to obtain a reliable picture of the antiglycation capacity of the investigated compounds, DPPH scavenging and oxygen radical absorbance capacity (ORAC) assays were performed. Furthermore, the anti–α–glucosidase activity of baicalein and baicalin was detected. Furthermore, to estimate cell permeability, preliminarily, the cytotoxicity of baicalein and baicalin was evaluated in HT–29 human colon adenocarcinoma cells using the MTT assay. Successively, the ability of the compounds to pass through the cytoplasmic membranes of HT–29 cells was detected as a permeability screen to predict in vivo absorption, showing that baicalein passes into cells even if it is quickly modified in various metabolites, being its main derivative baicalin. Otherwise, baicalin per se did not pass through cell membranes. Data show that baicalein is the most active compound in reducing glycation, α-glucosidase activity, and free radicals, while baicalin exhibited similar activities, but did not inhibit the enzyme α–glucosidase.