XPS and NMR analyze the combined forms of Pb in Cladophora rupestris subcells and its detoxification

Investigating the mechanism of Zn cross-linking of chitin in a mycelium-based leather substitute and its performance evaluation

Mycelium-based leather substitutes with a three-dimensional reticulated structure have attracted attention owing to the negative environmental impacts of natural and synthetic leather. This study utilised Ganoderma lucidum mycelium to prepare a mycelium-based leather substitute with zinc cross-linking (MF-Zn) and evaluated its physicochemical properties and sensory performance; the conventional Cr3+ tanning method was used as reference. Results demonstrated that Zn2+ and Cr3+ formed cross-links with the -OH and -NHOCH3 groups in the polysaccharides of chitin, while Zn2+ selectively bonded to a fraction of -NH2 groups in cystine and phenylalanine. The mycelium-based leather substitute with Zn cross-linking exhibited impressive tensile strength and tear strength of 7.0 MPa and 16.4 kN/m, respectively, while demonstrating desirable organoleptic properties. The free radical-scavenging capacity of MF-Zn was assessed, revealing a DPPH radical and hydroxyl radical scavenging rates of 39.4% and 52.7%, respectively. By successfully investigating the cross-linking mechanism of mycelial fibres with Zn2+ and obtaining the stabilised mycelium-based leather substitute, this study establishes a fundamental basis for the development of sustainable leather substitutes, meeting the requirements and facilitating significant advancements in low-carbon leather substitute production.

Preparation of multifunctional cellulose macromolecule blended fabrics through internal and external synergy by N1, N6-bis (ethylene oxide-2-ylmethyl) hexane-1,6-diamine

With the diversification of people's demand for textile functions, the preparation of multifunctional fabrics is still a current research hotspot. In this study, the water-soluble epoxy compound N1, N6-bis(oxiran-2-ylmethyl) hexane-1,6-diamine (EH) was introduced into cellulose macromolecule blended fabrics (cotton/modal) by two-phase vaporization technique, resulting in excellent wrinkle, hydrophobicity, and certain UV protection effects. It could be observed by electron microscopy that EH formed a polymer film on the fiber surface. In addition, the results of EDS scans and fiber swelling rate tests showed that EH was uniformly distributed and formed a cross-linked structure in the amorphous zones inside the fibers. Compared with the control fabrics, the wrinkle recovery angle of the EH-treated fabric was increased by 39.7 %. The fabrics could reach a contact angle of 136.9°, providing excellent hydrophobic effect. In addition, the fabrics achieved certain UV protection effects (UPF of 50+). The EH-treated fabrics were less stabilized in strong acid and alkali conditions, but exhibited greater durability in other environments. In summary, the internal and external synergistic effects of EH in forming polymer films on the fibers surface and internal cross-linking structures provided a cleaner, simple, and feasible method for the preparation of multifunctional cellulose macromolecule fibers textiles.

Differential Gene Expression and Metabolic Pathway Analysis of Cladophora rupestris under Pb Stress Conditions

This study aimed to analyze the transcriptome of C. rupestris under Pb²⁺ stress by using high-throughput sequencing technology, observe the changes of gene expression and metabolic pathway after three and five days under 1.0 and 5.0 mg/L of Pb²⁺ treatment, and analyze the differentially expressed genes (DEGs) and related functional genes after Pb²⁺ treatment. Metabolic pathways were revealed through Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Results show that DEGs increased significantly with the increase of Pb²⁺ concentration and stress time. A total of 32 genes were closely related to Pb²⁺ stress response. GO analysis identified two major transporter proteins, namely, ATP-binding transport protein-related (ABC transporters) and zinc finger CCHC domain containing protein (Zfp) in C. rupestris. Pthr19248, pthr19211, Zfp pthr23002, Zfp p48znf pthr12681, Zfp 294 pthr12389, and Zfp pthr23067 played important roles against Pb²⁺ toxicity and its absorption in C. rupestris. KEGG pathway analysis suggested that ABCA1, ATM, and ABCD3 were closely related to Pb²⁺ absorption. Pb²⁺ stress was mainly involved in metallothionein (MT), plant hormone signal transduction, ABC transporters, and glutathione (GSH) metabolism.