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In this work, smart edible coating and films with excellent UV barrier properties were prepared from alginate, whey protein isolate, and curcumin. The primary focus of this investigation centered on assessing the impact of whey protein and curcumin on the physical and functional properties of the alginate films. Whey protein reduced the film transparency while simultaneously enhancing the hydrophobicity and antioxidant properties of the alginate film. Curcumin imparted a yellow hue to the film, consequently decreasing the transparency of the film. It also substantially improved hydrophobicity, antioxidant activity, and UV-blocking efficiency within the films. Remarkably, curcumin demonstrated a significant reduction in the water vapor transmission rate of the film. For the preservation of apples, a higher concentration of curcumin was required, which effectively suppressed the respiration rate and moisture loss post-harvest, resulting in an extended shelf-life for the apples. As a result, the coated apples exhibited significantly reduced enzymatic browning and weight loss in comparison to their uncoated counterparts. Furthermore, these curcumin-containing films underwent a reversible color change from orange to red when exposed to ammonia vapor. This attribute highlights the potential of the developed coating and film as a smart, active food packaging solution, particularly for light-sensitive food products. [ABSTRACT FROM AUTHOR]

In this study, the dyeing performance and antibacterial properties of pomegranate (Punica granatum) peel extracts were investigated, when applied to hemp fabric. A tannin-rich natural dye was extracted using water at 100°C. As the antibacterial agent was sensitive to temperature, it was extracted using Soxhlet apparatus with methanol at 55°C. The color strength (K / S) values were investigated and found to increase in line with the dye concentration, dyeing time, and temperature. Optimal dyeing of the hemp fabric was achieved when applying 6% w / v of extract at 80°C for 60 min. This produced a yellowish-brown appearance. The dyed fabrics were rated as good to excellent for color fastness against washing, water, sea water, and perspiration. The dyed fabrics were next finished with the antibacterial agent extracted from the peel and tested for activity against Staphylococcus aureus (Gram positive) and Klebsiella pneumoniae (Gram negative), using the AATCC-100 (percentage reduction) test. The fabric was demonstrated to be 99.99% effective against Staphylococcus aureus, and this was conserved across 20 wash cycles. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) halogen-bonded organic frameworks were readily engineered by strong and directional effects of the primary Br⋯O and the secondary Br⋯π halogen bonding interactions from the tetrabromobenzene-1,4-dicarboxylic acid (H2Br4BDC) building molecule involving 100% supramolecular yields. The 2D assembly can function as a host layered framework for the intercalation of various guest solvents including acetone (ATN), ethanol (EtOH), dimethyl sulfoxide (DMSO), and ethylene glycol (EG) resulting in a 1 : 2 host : guest complexation stoichiometry viz. H2Br4BDC·2S (S = ATN (1ATN), EtOH (2EtOH), DMSO (3DMSO), and EG (4EG)). All the solvates show remarkable similarities in their 2D layered sheets and the bilayer distance significantly responds to the size, shape, molecular conformation, and strength of the hydrogen bonding capability of the intercalated solvent molecules. The transition between solvate formation and desolvation was found to be facile and reversible upon the desolvation–resolvation process. The estimated Br⋯O halogen bonding energy of the solvates is in the −0.6 to −1.7 kcal mol−1 range, which was determined by quantum-mechanical calculations based on density functional theory (DFT) calculations. Furthermore, to quantitatively identify the host–guest intermolecular interactions of these solvates, they were visually compared by Hirshfeld surface analysis. [ABSTRACT FROM AUTHOR]

This is the first investigation of a rhodamine B derivative (RBD)/cellulose acetate (CA) colorimetric test strip for Cu2+ sensing in water. The test strip allowed both semi-quantitative naked-eye detection and quantitative detection when spectroscopy was applied. A chemosensor, RBD, was doped into a CA solution and this was electrospun to produce a test strip. The average diameter of the electrospun fibers was 750±270 nm. The nonwoven test strip changed from off-white to pink when exposed to aqueous Cu2+ solutions. A linear relationship was found between the color strength of the test strip and the Cu2+ concentration (20–300 ppm, R2=0.989). The limit of detection (LOD) was 18 ppm. Alkaline treatment of the electrospun sample with sodium hydroxide produced partial deacetylation of the CA, reducing the number of acetyl groups while increasing the number of hydroxyl groups in the fibrous structure. Fiber swelling and improved wettability of the solid sensor was also observed. The treated sensor responded approximately 33 times faster to Cu2+ than the untreated sensor. When tested with Cu2+, the sensor produced K/S values approximately 5–10 times greater than when tested with Mn2+, Pb2+, Cd2+, Ni2+, Zn2+ or Sn2+, and three times greater than Fe2+. The electrospun sensor showed a slight improvement in Cu2+ adsorption after alkaline treatment. [ABSTRACT FROM AUTHOR]

The environmental-friendly, economical, and simple one pot formulation for enhanced antibacterial and mechanical property finishing on medical cotton fabrics was successfully developed and optimized using a central composite design in conjunction with response surface methodology. It combines the concepts of in situ synthesis of AgNPs and photocatalytic property of TiO2 in waterborne polyurethane as the finishing emulsion without additional organic reducing or stabilizing agent. The optimal formulation with contents of AgNO3 (240 ppm) and TiO2 NPs (980 ppm) exhibited excellent antibacterial activities against Klebsiella pneumoniae and Staphylococcus aureus with over 99% reduction and improved mechanical properties as well as non-toxicity to mammalian cells. [ABSTRACT FROM AUTHOR]