Adsorptive immobilization of agro-industrially produced crude laccase on various micro-biochars and degradation of diclofenac.

Lonappan, Linson; Liu, Yuxue; Rouissi, Tarek; Brar, Satinder Kaur; Verma, Mausam P. et Surampalli, Rao Y. (2018). Adsorptive immobilization of agro-industrially produced crude laccase on various micro-biochars and degradation of diclofenac. Science of The Total Environment , vol. 640-641 . pp. 1251-1258. DOI: 10.1016/j.scitotenv.2018.06.005.

Prévisualisation

PDF Disponible sous licence Creative Commons Attribution Non-commercial No Derivatives. Télécharger (1MB) | Prévisualisation

Résumé

Although enzymes are gifted with unique and unprecedented catalytic activity and selectivity over a wide range of pollutants, still their stability related issues often hinder their application in real environmental conditions. In this study, agro-industrially produced crude laccase was concentrated using ultrafiltration. Crude laccase was immobilized on pine wood (BC-PW), pig manure (BC-PM) and almond shell (BC-AS) biochar microparticles. Immobilization of laccase was investigated at various laccase activities on micro-biochars and the release (desorption) of the enzyme has been studied. It was observed that for all the biochars, as the initial concentration of laccase increased in the crude solution, the binding capacity and as result immobilization efficiency also increased. BC-PM was found to be the most effective (31.4 ± 3.1 U g⁻¹) at 10 U mL⁻¹ of enzyme activity followed by BC-AS (24.3 ± 4.8 U g⁻¹) and BC-PW (14.58 ± 3.3 U g⁻¹). In addition, the biochars were functionalized with citric acid for possible surface modifications and the effect of biochars for the adsorption of enzymes has been investigated. Isotherm studies of enzyme loading onto biochar established homogeneous monolayer adsorption as the major mechanism. The desorption of laccase from all biochars followed pseudo-second-order model. Immobilized laccase exhibited superior storage ability and shelf-life which were three times higher than free laccase. Finally, the immobilized laccase was used for the degradation of micropollutant, DCF and near 100% removal was obtained within 5 h at an environmentally relevant concentration (500 μg L⁻¹).

Type de document:	Article
Mots-clés libres:	laccase; biochar; biotransformation; adsorptive immobilization; isotherms; desorption
Centre:	Centre Eau Terre Environnement
Date de dépôt:	27 août 2018 20:36
Dernière modification:	07 juin 2020 04:00
URI:	https://espace.inrs.ca/id/eprint/7304

Gestion Actions (Identification requise)

Modifier la notice