Lactic acid bacteria produce a variety of antibacterial and larvicidal metabolites, which could be used to cure diseases caused by pathogenic bacteria and to efficiently overcome issues regarding insecticide resistance. In the current study, the antibacterial and larvicidal potential of Bis-(2-ethylhexyl) phthalate isolated from Lactiplantibacillus plantarum BCH-1 has been evaluated. Bioactive compounds were extracted by ethyl acetate and were fractionated by gradient column chromatography from crude extract. Based on FT-IR analysis followed by GC-MS and ESI-MS/MS, the active compound was identified to be Bis-(2-ethylhexyl) phthalate. Antibacterial potential was evaluated by disk diffusion against E. coli (12.33 ± 0.56 mm inhibition zone) and S. aureus (5.66 ± 1.00 mm inhibition zone). Larvicidal potency was performed against Culex quinquefasciatus Say larvae, where Bis-(2-ethylhexyl) phthalate showed 100% mortality at 250 ppm after 72 h with LC₅₀ of 67.03 ppm. Furthermore, after 72 h the acetylcholinesterase inhibition was observed as 29.00, 40.33, 53.00, 64.00, and 75.33 (%) at 50, 100, 150, 200, and 250 ppm, respectively. In comet assay, mean comet tail length (14.18 ± 0.28 μm), tail DNA percent damage (18.23 ± 0.06%), tail movement (14.68 ± 0.56 µm), comet length (20.62 ± 0.64 µm), head length (23.75 ± 0.27 µm), and head DNA percentage (39.19 ± 0.92%) were observed at 250 ppm as compared to the control. The current study for the first time describes the promising antibacterial and larvicidal potential of Bis-(2-ethylhexyl) phthalate from Lactiplantibacillus plantarum that would have potential pharmaceutical applications.

In this study, we evaluated the morphological behavior of polyurethane elastomers (PUEs) by modifying the soft segment chain length. This was achieved by increasing the soft segment molecular weight (Mn = 400–4000 gmol⁻¹). In this regard, polycaprolactone diol (PCL) was selected as the soft segment, and 4,4′-cyclohexamethylene diisocyanate (H₁₂MDI) and 1,6-hexanediol (HDO) were chosen as the hard segments. The films were prepared by curing polymer on Teflon surfaces. Fourier transform infrared spectroscopy (FTIR) was utilized for functional group identification in the prepared elastomers. FTIR peaks indicated the disappearance of −NCO and −OH groups and the formation of urethane (NHCOO) groups. The morphological behavior of the synthesized polymer samples was also elucidated using scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. The AFM and SEM results indicated that the extent of microphase separation was enhanced by an increase in the molecular weight of PCL. The phase separation and degree of crystallinity of the soft and hard segments were described using X-ray diffraction (XRD). It was observed that the degree of crystallinity of the synthesized polymers increased with an increase in the soft segment’s chain length. To evaluate hydrophilicity/hydrophobicity, the contact angle was measured. A gradual increase in the contact angle with distilled water and diiodomethane (38.6°–54.9°) test liquids was observed. Moreover, the decrease in surface energy (46.95–24.45 mN/m) was also found to be inconsistent by increasing the molecular weight of polyols.

A series of xanthan gum/titanium dioxide-based polyurethane elastomers were synthesized through the prepolymer method by the step growth polymerization. In the present work, xanthan gum was used as a bioactive material, with TiO₂ as a nanofiller. The structural characterization of newly prepared polyurethane samples was carried out with the help of Fourier Transform Infrared Spectroscopy. Thermogravimetric Analysis gave us the information about the thermal stability. Differential Scanning Calorimetry directs the thermal changes in the polyurethane samples. The Atomic Force Microscopy technique revealed that the degree of micro-phase separation increases by augmenting the % age of TiO₂, which was further confirmed by X-Ray Diffraction results. XRD confirmed the crystallinity of the final sample at about 2θ = 20°. Antimicrobial activity determined through the Disc Diffusion Method, and the results indicated that the synthesized polyurethane have antimicrobial activity. The water absorption capability of the polyurethane samples showed that these polymer samples are hydrophilic in nature.

The word "versatility" defines polyurethane. The reaction between di-isocyanate and polyester polyol led to the formation of polyurethane. The focus of this work is to generate eco-friendly, sustainable polyols by using waste material, such as polyethylene terephthalate (PET) which was further used to prepare hot melt polyurethane adhesive. PET was degraded via the chemical degradation method under controlled conditions, as prepared polyol was further used to prepare hot melt polyurethane adhesive with di-isocyanate (MDI), polyol (PEG), and chain extender (BDO). By taking into account the advantage of nanotechnology SiO₂ nanoparticles were incorporated to impart mechanical strength to prepared hot melt polyurethane adhesives. FTIR and NMR spectrographs confirm the formation of the final product by the absence of -NCO- peak and the presence of -NH- peak. Surface morphology and crystallinity results through AFM and XRD represent well-stabilized formulations by the continuous distribution of PET polyol, and SiO₂ in polyurethane matrix. The addition of PET polyol and SiO₂ provides mechanical stability to the prepared sample, by resisting the deformation at elevated temperatures, indicated by TGA/DSC thermograms. A remarkable improvement in adhesion properties and chemical resistance was observed in the prepared hot melt adhesives with an increase in melting viscosity and T-peel strength. These enhancements were attributed to the increased content of PET polyol and the incorporation of SiO₂ into the adhesive formulations. The current research provides evidence that recycled PET, when combined with optimized adhesive formulations, can be effectively used in hot melt adhesive applications across a variety of uses.

The current research was conducted to study the use of waste materials to isolate lignin, which was further used to prepare polyurethane hot-melt adhesives. To enhance the reactivity of lignin, its hydroxyl content was increased by hydroxymethylation, and then it was polymerized with 4,4′-methylenediphenyl diisocyanate (MDI), polyethylene glycol (PEG), and 1,4-butanediol (BDO) to prepare polyurethane hot-melt adhesives. SiO₂ nanoparticles were added to provide mechanical strength to the final polymer. The structure of the final polymer was confirmed by FT-IR spectroscopy. Morphological behaviors were analyzed by using SEM and XRD. Thermomechanical characteristics were studied by using thermogravimetric analysis (TGA\DSC). Finally, the adhesion properties were analyzed by using melting viscosity, softening temperature, and a T-peel strength test. The absence of the -NCO peak of monomers in the FT-IR spectra confirmed the completion of the reaction. The gradual decrease in thermal transition and increasing crystallinity in the DSC\TGA thermograms represent its stable thermal behavior. SEM and XRD show that the prepared hot-melt polyurethane adhesives have distinct crystallinity and peaks. Melting viscosity, softening temperature, and T-peel strength test exhibit the strong adhesive behaviors of the prepared biobased polymers in different time intervals under stress and heating conditions. HMPUA-4 with optimum values of lignin and SiO₂ nanoparticles is considered to be the best product due to its high adhesive properties and sustainability. Lignin’s strong antibacterial activity is also evidence that a promising polymeric adhesive was prepared that can be used in various fields.