Immobilizing Laccase on Different Species Wood Biochar to Remove the Chlorinated Biphenyl in Wastewater

Abstract

Biochars produced from two different wood species over a microwave assisted pyrolysis process were used as novel and green-based supports for immobilizing enzyme, laccase in particular. The results obtained from FT-IR, SEM and BET measurements indicated that Maple biochar with honeycomb structure has higher surface area and pore volume than Spruce biochar; and there exist O-H, C-H, C=O and C=C groups in biochars for potential chemical modification. The best laccase immobilization conditions identified from an orthogonal experiment were pH = 3, laccase concentration 16 g/L and contact time 8 h. Under such conditions, the high immobilization yield (64.2%) and amount (11.14 mg/g) of laccase on Maple biochar were achieved, leading to the significantly improved thermal stability of laccase. Moreover, the immobilized laccase is reusable and enhanced the enzymatic degradation of 4-hydroxy-3,5-dichlorobiphenyl (71.4% yield), thus creating a promising and novel type of adsorbent in the removal of polychlorinated biphenyls from wastewater.

Enzyme Immobilization Onto Biochar Produced by the Hydrothermal Carbonization of Biomass

“…The diameter of these spheres can be altered by changing the synthesis conditions. 11,14,15 Thus, synthesized biochar has two important properties that make it suitable for use in the field of catalysis, as a carrier for drugs with controlled release, 16 or for immobilization of enzymes (purified 17,18,19 or within microbial cells 20,21 ). First, it contains a high concentration of oxygen groups on the surface, which means that it can be easily connected to other substances with complementary features and it is suitable for the manufacture of functional nanocomposites.…”

Comparative study of single cultures and a consortium of white rot fungi for polychlorinated biphenyls treatment

“…2005; Li et al . 2018), although their exact role in the biodegradation process has not yet been fully elucidated (Field and Sierra‐Alvarez 2008).…”

Immobilization of laccase on magnetically separable biochar for highly efficient removal of bisphenol A in water

“…ABTS is a suitable substrate to determine the activity of laccase because ABTS can be oxidized by the catalytic reaction with laccase to generate spectrophotometrically measurable cation radicals (ABTS + ). [25][26][27] Additionally, 1 unit (U) of laccase activity was dened as the amount of laccase that can convert 1 mmol of ABTS into 50 mM of citric phosphate buffer per minute at 25 C. The activities of free or immobilized laccase were obtained by incubating a specic amount of laccase or L-MBC in 1 mmol of ABTS in 50 mM of citric phosphate buffer for 3 min at 25 C, and the increase in the absorbance at 420 nm was measured using a UV-vis spectrophotometer (Shimadzu UV-2450, Tokyo, Japan). Enzyme activity was calculated according to the following equations:…”