Bio-based and cost effective method for phenolic compounds removal using cross-linked enzyme aggregates

Kheireddine Sellami (1) , Annabelle Couvert (1) , Noureddine Nasrallah (2) , Rachida Maachi (2) , Nassima Tandjaoui (3) , Mahmoud Abouseoud (2) , Abdeltif Amrane (1)

1 ISCR - Institut des Sciences Chimiques de Rennes
2 USTHB - Université des Sciences et de la Technologie Houari Boumediene = University of Sciences and Technology Houari Boumediene [Alger]
3 Université Ibn Khaldoun de Tiaret = University of Tiaret

This work aimed at presenting a green method using a new source of peroxidase isolated from Raphanus sativus var. niger (RSVNP) in immobilized form, for the treatment of wastewater. To ensure stability and enzymatic activity in the biodegradation process, RSVNP was immobilized as a cross-linked enzyme aggregate (CLEAs). With more than 29% of recovered activity and 85% aggregation yield, acetone was selected as the best precipitating agent. The formed protein aggregates required 2% (v/v) of glutaraldehyde (GA) concentration and a ratio of 9:1 (v/v) enzyme (E) amount to cross-linker (E/GA). Compared to the free enzyme, RSVNP-CLEAs were found more chemically and thermally stable and exhibited good storage stability for more than 8 weeks. In addition, RSVNP-CLEAs were evaluated for their ability to remove phenol and p-cresol from aqueous solution by varying several operating conditions. A maximal yield (98%) of p-cresol conversion was recorded after 40 min; while 92% of phenol was degraded after 1 h duration time. The reusability of RSVNP-CLEAs was tested, displaying 71% degradation of phenol in the third batch carried out and more than 54% was achieved for p-cresol after four successive reuses in the presence of hydrogen peroxide at 2 mM concentration.

Mots clés: CLEAs; Enzymatic transformation; Green process; Peroxidase immobilization; Phenols

Domaines: Chimie

Kheireddine Sellami, Annabelle Couvert, Noureddine Nasrallah, Rachida Maachi, Nassima Tandjaoui, et al.. Bio-based and cost effective method for phenolic compounds removal using cross-linked enzyme aggregates. Journal of Hazardous Materials, 2021, 403, pp.124021. ⟨10.1016/j.jhazmat.2020.124021⟩. ⟨hal-03003209⟩