Kookmin University

This research aims to develop an antifungal packaging film to mitigate the quality deterioration of mass-produced bread for industrial purposes. Various antifungal agents were tested against four target fungi; Aspergillus niger, A. flavus, Penicillium corylophilum, and Neurospora sp.; commonly found in bread, to replace the commercial antifungal film. Among them, Cinnamomum cassia essential oil (CEO) exhibited strong antifungal activity, with MIC values below 100 ppm against all tested strains. We implemented the CEO-incorporated powder onto the multilayered packaging film and subsequent packaging trials were conducted on the industrial packaging machinery. Organoleptic analyses using electronic tongue and electronic nose revealed that the application of CEO maintained the bread's flavor and aroma throughout storage, implying the newly developed CEO-treated film was comparably preferred to the conventional material. Therefore, this investigation highlights the promising potential of CEO's effective antifungal agent to combat bread quality deterioration during distribution for industrial operations.

d-Ribose is essential for critical cellular functions and the synthesis of antiviral nucleosides. However, traditional chemical synthesis and fermentation methods of d-ribose production suffer from low yields and inefficient resource utilization. Here, we present a highly efficient enzymatic cascade strategy that utilizes selective phosphorylation and dephosphorylation processes, coupled with ATP regeneration to convert d-xylose into d-ribose with high yield. By optimizing this enzyme cascade, we achieved a substantial increase in d-ribose yield from 23.4 % to 93.5 % mol/mol, effectively overcoming the equilibrium limitations of sugar conversion processes. Notably, our approach allows for the selective conversion of d-xylose to d-ribose in lignocellulosic hydrolysates, even in the presence of d-glucose. This work demonstrates the highly efficient enzymatic conversion of d-xylose into d-ribose offering a competitive alternative to existing chemical synthesis methods. Our findings provide a novel approach to cellulosic biomass valorization and represent a significant contribution to the field of biorefinery.

High efficiency of charge carrier conduction is crucial for photoelectrical performance in ultraviolet C (UVC) photodetectors (PDs) based on heteroepitaxial beta-gallium oxide (β-Ga₂O₃) thin films. However, the presence of in-plane rotational domains due to anisotropic symmetry severely degraded the efficiency of charge carrier conduction by trapping and recombination of carriers in conventional lateral PD (LPD). Here, we demonstrate an approach that enables vertical conduction configuration while preserving the high crystallinity of epitaxial Si-doped β-Ga₂O₃ (Si:Ga₂O₃) through the epilayer transfer using a hole pattern sapphire nanomembrane (HPSN) growth template. Based on the characterization of domain orientation and photoresponsivity in transferred epitaxial Si:Ga₂O₃ membranes, we reveal the defect-related anisotropic conduction arising from the vertical interdomain and lateral intradomain conduction. Compared to the indirect intradomain pathway in LPD, the vertical PD (VPD) exhibited high efficiency of charge carrier conduction through the direct interdomain pathways. As a result, the self-powered VPD exhibits high rectifying characteristics with a high detectivity of 1.02 × 10¹³ Jones and a fast response time of 93 ms. Moreover, the multipixel UVC imaging PD arrays have been successfully demonstrated without any external applied bias, showing high recognition rates and practical utility for reliable UVC imaging applications. Our work not only demonstrates the feasibility of obtaining single-crystal epitaxial membranes for a wide range of material systems but also provides pathways for overcoming material limitations with defect-induced optoelectrical systems.