Poly(butylene adipate-co-terephthalate) (PBAT), a polyester made of terephthalic acid (TPA), 1,4-butanediol, and adipic acid, is extensively utilized in plastic production and has accumulated globally as environmental waste. Biodegradation is an attractive strategy to manage PBAT, but an effective PBAT-degrading enzyme is required. Here, we demonstrate that cutinases are highly potent enzymes that can completely decompose PBAT films in 48 h. We further show that the engineered cutinases, by applying a double mutation strategy to render a more flexible substrate-binding pocket exhibit higher decomposition rates. Notably, these variants produce TPA as a major end-product, which is beneficial feature for the future recycling economy. The crystal structures of wild type and double mutation of a cutinase from Thermobifida fusca in complex with a substrate analogue are also solved, elucidating their substrate-binding modes. These structural and biochemical analyses enable us to propose the mechanism of cutinase-mediated PBAT degradation.

Developing a new type of superhydrophilic/underwater superoleophobic oil/water separation membrane with high separation efficiency, high throughput and bacteria separation has essential theoretical and practical significance for treating oily and medical wastewater. This work modified commercial PVDF membranes by knife coating and cross-linking, and PVDF/PVA/LPB/MOF hybrid separation membranes are manufactured. Hydrophilic polyvinyl alcohol (PVA) endows the separation membrane with good hydrophilicity. Lauramidopropyl Betaine (LPB) enhances intermolecular hydrogen bonding and improves the mechanical properties of the membrane. A Metal-organic framework (MOF) with excellent biocompatibility, UiO-66-NH₂, plays a vital role in the separation of bacteria. The results of the morphology and surface chemistry of characterization analysis show that the PVDF/PVA/LPB/MOF hybrid separation membrane exhibits excellent superhydrophilicity (with a contact angle of 2°) and high-water flux (15600 L/m²h) and high separation efficiency (99%), and the nature of filtering bacteria while separating oil. After modification, the separation efficiency increased from 30% to 99%, showing strong oil stain resistance. Our finding suggests that the new type of super-hydrophilic/underwater superoleophobic oil/water separation membrane has potential value in practical applications.

Zirconium based metal organic frameworks (Zr-MOFs) have become popular in engineering studies due to their high mechanical stability, thermostability and chemical stability. In our work, by using a theoretical kinetic adsorption isotherm, we can exert MOFs to an acid dye adsorption process, experimentally exploring the adsorption of MOFs, their external behavior and internal mechanism. The results indicate their spontaneous and endothermic nature, and the maximum adsorption capacity of this material for acid orange 7 (AO7) could be up to 358 mg·g⁻¹ at 318 K, estimated by the Langmuir isotherm model. This is ascribed to the presence of an open active metal site that significantly intensified the adsorption, by majorly increasing the interaction strength with the adsorbates. Additionally, the enhanced π delocalization and suitable pore size of UiO-66 gave rise to the highest host–guest interaction, which further improves both the adsorption capacity and separation selectivity at low concentrations. Furthermore, the stability of UiO-66 was actually verified for the first time, through comparing the structure of the samples before and after adsorption mainly by Powder X-ray diffraction and thermal gravimetric analysis.