Artificial metalloenzymes that combine the advantages of natural enzymes and metal catalysts have been getting more attention in research. As a proof of concept, an artificial nanometalloenzyme (CALB-Shvo@MiMBN) was prepared by co-encapsulation of metallo-organic catalyst and enzyme in a soft nanocomposite consisting of 2-methylimidazole, metal ions, and biosurfactant in mild reaction conditions using a one-pot self-assembly method. The artificial nanometalloenzyme with lipase acted as the core, and the metallo-organic catalyst embedded in micropore exhibited a spherical structure of 30–50 nm in diameter. The artificial nanometalloenzyme showed high catalytic efficiency in the dynamic kinetic resolution of racemic primary amines or secondary alcohols compared to the one-pot catalytic reaction of immobilized lipase and free metallo-organic catalyst. This artificial nanometalloenzyme holds great promise for integrated enzymatic and heterogeneous catalysis.

In this study, an alkali freeze-thaw pretreatment protocol was investigated to efficiently enhance enzymatic hydrolysis of chitin into N-acetyl glucosamine (GlcNAc) at high concentrations. The optimal conditions for alkali freeze-thaw...

The new green biobased pentamethylene diisocyanate (PDI) trimer curing agent has lower-life-cycle carbon emissions than the petrochemical-based hexamethylene diisocyanate (HDI) trimer curing agent, and its performance is similar to that of petrochemical-based products. This work focused on the synthesis, allophanate modification, free PDI monomer removal, and coating performances of PDI isocyanurate trimers. The results showed that optimal synthesis of PDI isocyanurate trimers used 2-hydroxypropyltrimethylisooctanoate ammonium salt (TMR) as a catalyst with 0.4 wt ‰ added and a reaction time of 120 min. The best free PDI monomer removal by molecular distillation used a removal temperature of 130 °C, a scraper speed of 350 rpm, and a feed rate of 3 mL·min–1, with two total removals. Self-made and allophanate-modified PDI isocyanurate trimers showed high values in physical and chemical properties. The water resistance, acid and alkali resistance, and aging resistance of the self-made and allophanate-modified PDI isocyanurate trimers were similar to or even better than those of petrochemical-based HDI products. These results indicate the application potential of biobased PDI-trimer curing agents.

PLD@MSNC transforms a two-phase system into an emulsion phase, and enhances transphosphatidylation.

No abstract