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Thamnolia subuliformis (Ehrh.) W. Culb is a species of lichen with edible and medicinal applications in China. Our previous studies demonstrated that the methanol extract of Thamnolia subuliformis (METS) exhibits broad antibacterial activity and stability against foodborne pathogens. This study aimed to investigate the antibacterial mechanism of METS against Staphylococcus aureus using nontargeted metabolomics, focusing on cell wall and membrane damage. The results revealed that the minimum inhibitory concentration (MIC) was 0.625 mg ml−1 and that METS had good biosafety at this concentration. METS caused significant damage to the cell wall and membrane integrity, based on both morphological observation by electron microscopy and the leakage of alkaline phosphatase, protein, and nucleic acid in the cell cultures. Treatment with METS at the MIC disrupted the lipid metabolism of S. aureus , causing a decrease in the metabolism of various phospholipids and sphingolipids in the cell membrane and an increase in the ratio of saturated fatty acids to unsaturated fatty acids. Moreover, it influenced intracellular amino acid and energy metabolism. These results shed light on the antibacterial mechanism of METS against S. aureus while also serving as a reference for the further development of natural antibacterial compounds derived from Thamnolia subuliformis. [ABSTRACT FROM AUTHOR]

The problem of antibiotic resistance genes (ARGs) caused by heavy metals has attracted extensive attention of human beings. Zn, a widely used feed additive, has a very high residue in swine manure, but the distribution characteristics of ARGs imposed by Zn in anaerobic digestion (AD) products are not clear. In this study, the behaviour of mobile genetic elements (MGEs), bacterial community, and their association with ARGs were determined in the presence of 125 and 1250 mg L–1 Zn in AD system of swine manure. Zn-treated enriched the abundance of ARGs, and produced some new genotypes that were not detected in CK treatment. In addition, low concentration of Zn significantly increased the relative abundance of ARGs, as compared to higher Zn and CK group. Correspondingly, the abundances of most top30 genus were highest in ZnL (125 mg L–1 Zn), followed by CK and ZnH (1250 mg L–1 Zn). Notably, network analysis showed that the relationship between ARGs and MGEs is closer than that ARGs and bacteria, suggesting that ARGs increased in Zn-treated, especially low level Zn, may be due to the amplification transfer of ARGs among varied microorganisms by horizontal transfer with MGEs. Therefore, strengthen the management of in livestock manure is crucial to control the spread of ARGs in organic fertilizers. [ABSTRACT FROM AUTHOR]

Despite the rapid development of perovskite solar cells (PSCs), defects in the devices continue to impede further improvements in power conversion efficiency and operational stability. In this work, the use of hydroxylamine‐O‐sulfonic acid as a bifunctional molecule to enhance the performance of PSCs is described. Strong coordination exists between the sulfonic acid group and uncoordinated Pb2+ of perovskite, while the NH bond on amino group interacts with uncoordinated I−. Thus, due to the synergistic contribution of sulfonic acid group and amino groups, the high‐quality perovskite film with good crystallinity and low defect density is achieved. As a result, the optimal devices exhibit an enhanced efficiency of 23.33%, which is much higher than that of the control device (21.53%). Notably, the optimized target device exhibits excellent long‐term operational stability, retaining over 90% of its initial efficiency after 480 h at 65 °C, over 93% after a continuous illumination test for 650 h, and over 96% after nearly 1400 h of air storage. In contrast, the control device demonstrates poorer stability. In these results, it is suggested that selecting a dual‐functional additive is a promising approach to enhance efficiency and maintain stability in PSCs. [ABSTRACT FROM AUTHOR]

Wounds infected with multidrug‐resistant (MDR) bacteria are increasingly threatening public health and challenging clinical treatments because of intensive bacterial colonization, excessive inflammatory responses, and superabundant oxidative stress. To overcome this malignant burden and promote wound healing, a multifunctional cryogel (HA/TA2/KR2) composed of hyaluronic acid (HA), tannic acid (TA), and KR‐12 peptides is designed. The cryogel exhibited excellent shape‐memory properties, strong absorption performance, and hemostatic capacity. In vitro experiments demonstrated that KR‐12 in the cryogel can be responsively released by stimulation with hyaluronidase produced by bacteria, reaching robust antibacterial activity against Escherichia coli (E. coli), MDR Pseudomonas aeruginosa (MDR‐PA), and methicillin‐resistant Staphylococcus aureus (MRSA) by disrupting bacterial cell membranes. Furthermore, the synergetic effect of KR‐12 and TA can efficiently scavenge ROS and decrease expression of pro‐inflammatory cytokines (tumor necrosis factor (TNF)‐α & interleukin (IL)−6), as well as modulate the macrophage phenotype toward the M2 type. In vivo animal tests indicated that the cryogel can effectively destroy bacteria in the wound and promote healing process via accelerating angiogenesis and re‐epithelialization. Proteomic analysis revealed the underlying mechanism by which the cryogel mainly reshaped the infected wound microenvironment by inhibiting the Nuclear factor kappa B (NF‐κB) signaling pathway and activating the Janus kinase‐Signal transducer and activator of transcription (JAK‐STAT6) signaling pathway. Therefore, the HA/TA2/KR2 cryogel is a promising dressing candidate for MDR bacteria‐infected wound healing. [ABSTRACT FROM AUTHOR]

Although near‐infrared (NIR) light‐based photothermal therapies have shown therapeutic potential for infected wounds, the attenuation of NIR light intensity in tissue has severely limited the usage in deep bacterial infections. Herein, magneto‐thermal responsive bilayer microneedles (Fe‐Se‐HA MNs) consisting of functionalized hyaluronic acid (HA), ferro‐ferric oxide (Fe3O4), and micelle‐protected selenium nanoparticles (SeNPs@LAS) are constructed to overcome this challenge based on a self‐designed disk‐shaped electromagnetic field device (Disk‐ZVS). The electromagnetic field generated by the Disk‐ZVS shows virtually no intensity attenuation in living tissue. Finite element simulations showed that the field intensity and electromagnetic loss are concentrated on the tips of Fe‐Se‐HA MNs. The MNs are able to puncture hard scabs, penetrate into bacterial biofilms, and perform effective magnetic‐thermal conversion for deep hyperthermia sterilization. Following, the Fe‐Se‐HA MNs can be gradually degraded by excessive hyaluronidase in diabetic wound to release SeNPs, which reduce reactive oxygen species (ROS) to regulate wound redox homeostasis. Meanwhile, the SeNPs are beneficial to angiogenesis, which facilitates blood vessel formation and promotes wound repair. Therefore, various functions can be achieved for the Fe‐Se‐HA MNs, such as magneto‐thermal disinfection, deep and non‐invasive tissue penetration, anti‐inflammation, and pro‐angiogenesis, which shows great potential as an adjunctive therapy for infected diabetic wounds. [ABSTRACT FROM AUTHOR]