Using Laccases in the Nanoflower to Synthesize Viniferin

Abstract

Abstract:The laccase-incorporated nanoflower was fabricated and characterized by scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). SEM images indicate that the laccase-incorporated nanoflower has a high surface area, which may facilitate the mass transfer of the substrate and the product. FTIR spectrums identify the existence of laccase in the nanoflowers. The novel immobilized laccase was used for the synthesis of viniferin. The reaction conditions had been optimized and the laccase-incorporated nanoflower can show its maximum specific activity (16.3 µmol/g/h) under the optimal reaction conditions. The specific activity of the laccase in the nanoflowers is enhanced about 2.2-fold compared with free laccase in solution without copper (II) ions. Furthermore, the laccase in the nanoflowers shows an increase in specific activity of~180% compared with free laccase in a solution containing high concentrations (similar to the concentration in the flower) of copper (II) ions. The results also indicate that the laccase in the nanoflowers retain 93.2% of its initial specific activity even after ten continuous batches.

Impact of Environmental Factors on Stilbene Biosynthesis

“…Resveratrol oligomerization has been achieved in vitro by enzymatic oxidation utilizing horseradish peroxidase [172,173] or laccase-like stilbene oxidase from B. cinerea [174,175]. It has been proposed that peroxidases (POD or POX EC 1.11.1.7) located in the plant cell wall and vacuole are responsible for oxidative polymerization of resveratrol to form its natural oligomers [157,176].…”

Co-Immobilization of Tri-Enzymes for the Conversion of Hydroxymethylfurfural to 2,5-Diformylfuran

“…Hence, the repeated reaction, separation and rinsing steps in successive reactions may give rise to a slight loss of DFF yield. The outstanding reusability can be attributed to: (1) the stable conjunction between the tri-enzymes and the hybrid nanoflowers via the coordinate bond between the three enzymes and Cu ions in the nanoflowers, (2) the enhanced rigidification of the tri-enzymes’ tertiary structure by immobilization, and (3) the remarkable mechanical stability of the Cu 3 (PO 4 ) 2 nanoflower matrix, which was demonstrated by our previous works in which lipase-incorporated nanoflowers retained 98.7% of the initial enzyme activity and 95.6% of the initial E value after 10 continuous batches for resolution of ( R , S )-2-pentanol and laccase, and in other nanoflowers 93.2% of the initial activity for synthesizing viniferin was maintained after 10 consecutive runs [59,60]. The perfect reusability of co-immobilized tri-enzymes permits their industrial amplification potential for producing DFF.…”

Facile Fabrication of a Novel Copper Nanozyme for Efficient Dye Degradation

“…The Fourier transform infrared (FTIR) spectra of copper phosphate, tryptophan, and CNZ were recorded with the wavelength from 400 to 4000 cm –1 (Figure ). The peaks at 1047 and 559 cm –1 (in curves a and c) are caused by the asymmetric stretching vibration and bending vibration of PO 4 3– , respectively . The sharp absorption peak at 3404 cm –1 is the result of the vibration of N–H in the indole ring .…”

“…3− , respectively. 26 The sharp absorption peak at 3404 cm −1 is the result of the vibration of N−H in the indole ring. 27 The two poor peaks at 3045 and 1666 cm −1 are triggered by the stretching vibration and asymmetric bending of N−H (−NH 3+ ).…”