Cetyl trimethyl ammonium bromide-activated lipase from Aspergillus oryzae immobilized with Cu3(PO4)2⋅3H2O via biomineralization for hydrolysis of olive oil

Application of laccase-inorganic nanoflowers based time-temperature integrator to real-time monitor the freshness of pasteurized milk

A time-temperature integrator (TTI) based on laccase@Cu3(PO4)2 nanoflowers (laccase@NFs) was created to monitor the freshness of pasteurized milk during storage. To address the challenges of easy inactivation, poor stability, and high use-cost of laccase in the application of TTI, laccase@NFs were synthesized by ultrasonic-assisted biomineralization. The laccase@NFs-based TTI was created through the enzymatic reaction between laccase and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid ammonium salt), and the effects of laccase@NFs addition amount on the reaction rate, discoloration lifetime and activation energy (Ea) were discussed. Furthermore, the spoilage pattern and kinetic properties of pasteurized milk were explored based on titratable acidity. The measurement of the Ea was determined as 49.98 kJ/mol, and an investigation was conducted to assess the suitability of the TTI with pasteurized milk under both constant and variable temperature conditions. This research aims to contribute valuable insights into the application of enzymatic TTI in monitoring the shelf life of pasteurized milk.

Chitosan-Copper Hybrid Nanoflowers: A Novel Nanopesticide for Controlling Rhizoctonia solani Infection in Crops

Copper-based nanomaterials are effective alternatives to traditional pesticides due to their antibacterial properties. However, the high cost and low dispersity limit their application. In this study, we synthesized cost-effective, eco-friendly, and stable chitosan-copper hybrid nanoflowers (CS-Cu HNFs) through facile self-assembly to manage agricultural diseases caused by the fungal pathogen (Rhizoctonia solani). The results show that CS-Cu HNFs, which utilized chitosan and copper phosphate as primary scaffolds, were formed via a series of nucleation, aggregation, self-assembly, and anisotropic growth processes. 200 mg/L CS-Cu HNFs exhibited an excellent inhibitory effect on R. solani, which was 6.11 times that of CuO nanoparticles, despite CS-Cu HNFs containing only 45% of Cu as that in CuO nanoparticles. Additionally, CS-Cu HNFs significantly reduced R. solani infection in various crops and displayed broad-spectrum antibacterial activity. This research provides new insights into the preparation and application of organic-inorganic hybrid nanoflowers as nanopesticides.