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The purpose of this study was to enhance the antimicrobial activity of bagasse paper by coating the paper with bismuth oxide (Bi2O3) and using it to accelerate the process of wound healing. Paper sheets were prepared from sugarcane waste (bagasse). First, the paper sheets were coated with different Bi2O3 concentrations to improve the antimicrobial activity of the paper. After that, the paper sheets were allowed to dry in an oven at 50 °C for 3 h. Then, in vitro antimicrobial activity was evaluated against different microbial species, including Gram-negative bacteria (i.e., Klebsiella pneumonia, Escherichia coli) and Gram-positive bacteria (i.e., Staphylococcus aureus, Streptococcus pyogenes). The obtained results showed that the paper coated with 25% and 100% Bi2O3 had activity against all models of bacteria; however, the paper coated with 100% Bi2O3 composite had the strongest inhibitory effect. Then, bagasse paper was coated with 100% Bi2O3 and different antibiotics, to investigate their wound-healing potency in a wounded rat model for 14 days. Moreover, the paper coated with 100% Bi2O3 inhibited the cellular migration in vitro. Conclusively, coating paper with Bi2O3 enhances the wound-healing potential when applied to wounds. This impact could be ascribed to Bi2O3's broad antibacterial activity, which reduced infection and accelerated the healing process. [ABSTRACT FROM AUTHOR]

This study was conducted to determine what effects nanoparticles (NPs) like TiO2, ZnO, and Ag may pose on natural attenuation processes of petroleum hydrocarbons in contaminated soils. The solid NPs used were identified using x‐ray diffraction technique and their average size was certified as 18.2, 16.9, and 18.3 nm for Ag‐NPs, ZnO‐NPs, and TiO2‐NPs, respectively. NPs in soil microcosms behave differently where it was dissolved as in case of Ag‐NPs, partially dissolved as in ZnO‐NPs or changed into other crystalline phase as in TiO2‐NPs. In this investigation, catabolic gene encoding catechol 2,3 dioxygenase (C23DO) was selected specifically as biomarker for monitoring hydrocarbon biodegradation potential by measuring its transcripts by RT‐qPCR. TiO2‐NPs amended microcosms showed almost no change in C23DO expression profile or bacterial community which were dominated by Bacillus sp., Mycobacterium sp., Microbacterium sp., Clostridium sp., beside uncultured bacteria, including uncultured proteobacteria, Thauera sp. and Clostridia. XRD pattern suggested that TiO2‐NPs in microcosms were changed into other non‐inhibitory crystalline phase, consequently, showing the maximum degradation profile for most low molecular weight oil fractions and partially for the high molecular weight ones. Increasing ZnO‐NPs concentration in microcosms resulted in a reduction in the expression of C23DO with a concomitant slight deteriorative effect on bacterial populations ending up with elimination of Clostridium sp., Thauera sp., and uncultured proteobacteria. The oil‐degradation efficiency was reduced compared to TiO2‐NPs amended microcosms. In microcosms, Ag‐NPs were not detected in the crystalline form but were available in the ionic form that inhibited most bacterial populations and resulted in a limited degradation profile of oil, specifically the low molecular weight fractions. Ag‐NPs amended microcosms showed a significant reduction (80%) in C23DO gene expression and a detrimental effect on bacterial populations including key players like Mycobacterium sp., Microbacterium sp., and Thauera sp. involved in the biodegradation of petroleum hydrocarbons. [ABSTRACT FROM AUTHOR]