This study focuses on the synthesis of new materials based on hydroxyethyl cellulose (HEC) and (3-aminopropyl)triethoxysilane (APTES) in a single-step process, adopting an efficient and innovative approach. The structural and physical properties of the synthesized polymers were meticulously characterized using analytical techniques, including FTIR/ATR, ¹H, ¹³C, 135-DEPT, ²⁹Si NMR, elemental analysis, and TGA/DTA. The morphology and amorphous profile of HEC-APTES were examined through SEM-EDX and XRD, respectively. In this study, a comprehensive analysis was conducted to gain a deeper understanding of the underlying mechanism and critical reaction conditions governing the interaction between HEC and the organosilane reagent. Various reaction parameters, such as reaction time, silane molar ratio (0.5:1, 1:1, 2:1, and 3:1 relative to HEC), and the autocatalysis of HEC alkoxides, were systematically investigated. Particularly, the combined influence of the reaction medium and the amount of added APTES on the grafting mechanism and mode was carefully examined. Lastly, an assessment of the solubility, dispersion, contact angle and bioactivity against various types of bacteria and fungi in the HEC-APTES samples was conducted to conclude this study. HEC-APTES demonstrates notable antifungal activity against Rhodotorula glutinis, Geotrichum candidum, and Aspergillus niger, with minimum fungicidal concentrations (MFC) of >20 mg/L, 2.5 mg/L, and 2.5 mg/L, respectively.

This study aimed to characterize the fermentation of commercial xylooligosaccharide (XOS) using Lactiplantibacillus plantarum S61. XOS was utilized as the main carbon source in a modified MRS medium (MRSm) at concentrations of 1%, 2%, 4%, and 6% (w/v). The growth of L. plantarum S61 was tracked daily over a week and compared to a control MRS medium using glucose as the main carbon source. The pH, total free acidity, and biomass were analyzed during fermentation, and the resulting fermentation product was analyzed for its content of fatty acids, total polyphenols, and the production of antioxidant and antimicrobial metabolites. The findings revealed that L. plantarum S61 thrived in MRSm, particularly at a 6% XOS concentration, which was identified as the best condition among the four tested concentrations (1%, 2%, 4%, and 6%). The fermentation of XOS by L. plantarum S61 significantly increased the total phenolic content and antioxidant activity compared to glucose, with the highest phenolic content observed at 6% XOS (6.70 ± 0.01 mg GAE/g). The strains produced various organic acids including lactic, malic, and oxalic acids from glucose and XOS. Notably, the strains yielded a broader range of organic acids with higher contents in the presence of XOS, leading to enhanced antifungal and antibacterial activities compared to glucose. Significant antibacterial activity was observed against Gram-negative bacteria, particularly Salmonella enterica, with inhibition zones of 20.25 mm and 11.75 mm for XOS (5% and 6%) and glucose, respectively. For Gram-positive bacteria, S. aureus and M. luteus exhibited inhibition zones of 20.01 mm for XOS 6% and 10.25 mm for glucose. In terms of antifungal activity, the strongest inhibition was observed against Rhodotorula glutinis, with inhibition zones of 26.00 mm for XOS 6% and 20.04 mm for glucose. The fermentation product of XOS by L. plantarum S61 showed significant inhibitory effects against pathogenic bacteria and yeasts, suggesting its potential application in the manufacturing of preservatives with antifungal properties and pharmaceutical products targeting pathogenic and spoilage yeasts.

This study investigates the formation of layer-by-layer emulsions for carvacrol encapsulation, using sodium caseinate as the first layer, and montmorillonite particles as the second layer, under two pH conditions (3 and 7). Dynamic light scattering and zeta potential results indicated improved stability at montmorillonite to caseinate emulsion ratios of 2:1 at pH 7 and 4:1 at pH 3, characterized by stable zeta potentials of -33.3 ± 1.87 mV and - 23.7 ± 1.97 mV, respectively. Isothermal titration calorimetry analysis confirmed that electrostatic interactions were the primary driving force for multilayer formation at pH 3, while hydrophobic and hydrogen bonding interactions likely dominated at pH 7. The process was spontaneous at both pH levels, with negative Gibbs free energy. Layer-by-layer emulsions showed superior encapsulation efficiency and retention of carvacrol, with a loading capacity of 21.84 ± 0.09 mg/g at pH 7. Furthermore, these formulations enhanced the antimicrobial efficacy of carvacrol.

Encapsulating carvacrol offers a promising approach to improving its stability, delaying oxidation, and enhancing its biological activity. This study explores the combined effects of alginate, caseinate, and montmorillonite on carvacrol emulsion stability to maximize encapsulation efficiency (EE). Box-Behnken experimental design was used to optimize the formulation, varying the concentrations of alginate (2-4 % w/w), caseinate (0-2 % w/w), and montmorillonite (0-2 % w/w). Emulsion stability was assessed based on droplet size, zeta potential, and yield stress, EE and microcapsule loading capacity. The results demonstrated that alginate and caseinate contribute to emulsion stability, while montmorillonite further reinforces the system by acting as a mechanical barrier, improving encapsulation and controlled release. The optimal formulation was 3.37 % w/w alginate, 2 % w/w caseinate, and 1 % w/w montmorillonite, which yielded an EE of 98.61 % and enhanced emulsion stability. The stabilizing mechanism involves increased steric repulsion between droplets and a gel-like network that resists coalescence and phase separation. Additionally, in vitro, release kinetics, and antimicrobial assays in food-simulating media confirmed the improved performance of the optimized formulation. These findings highlight the potential of combining clay minerals with biopolymer emulsifiers to create stable and efficient essential oil encapsulation systems, paving the way for more effective applications in the food industry.