Evaluation of p-cresol degradation with polyphenol oxidase (PPO) immobilized in various matrices

Abstract

p-Cresol is an environmental pollutant due to its vast use, toxicity and persistence, nevertheless, its degradation in an enzyme is unclear. In this study, we used Pleurotus sp. isolate VLECK02 polyphenol oxidase (PPO) for the determination of p-cresol degradation. On the basis of UV, FT-IR and chromatographic (HPLC and GC–MS) analysis, 4-methylcatechol was identified as the main metabolite of p-cresol catabolism. In addition, batch and semi-continuous degradation of p-cresol (10 and 20 mM) were studied and compared by free and immobilized PPO in different matrices like sodium alginate (SA), sodium alginate–polyvinyl alcohol (SA–PVA) and sodium alginate–polyvinyl alcohol–silver nanoparticles (SA–PVA–AgNPs). The experimental data showed that an enzyme (PPO) immobilized in SA–PVA–AgNPs was completely degraded p-cresol at initial concentrations of 10 and 20 mM within 30 h. These results suggest that the enzyme immobilized in SA–PVA–AgNPs has achieved higher degradation rates at a given time than free PPO and PPO immobilized in SA–PVA and SA. The SA–PVA–AgNPs and SA–PVA immobilized enzyme could be reused for more than 12 and 8 cycles, respectively, without losing any degradation capacity. Moreover, the immobilized PPO showed higher tolerance to various temperatures and pH than free PPO. Hence, immobilized PPO could be useful for the bioremediation of environment contaminated with phenolic compounds like p-cresol.Electronic supplementary materialThe online version of this article (doi:10.1007/s13205-016-0547-y) contains supplementary material, which is available to authorized users.

Analytical study of effective biodegradation of p-cresol using Serratia marcescens ABHI001: application in bioremediation

“…Thus, the FT-IR analysis confirmed that p-cresol was degraded into other compounds. This phenomenon has also been reported in the study by Edalli et al, in which the IR spectrum of metabolites produced by the degradation of p-cresol showed shifting of characteristic absorption bands vis-a `-vis at its initiate state (Edalli et al 2016). Furthermore, Huang et al investigated the microbial biodegradation of 3,5xylenol or m-cresol by P. putida NCIMB 9869 through FT-IR spectroscopy (Huang et al 2006).…”

Versatile Fungal Polyphenol Oxidase with Chlorophenol Bioremediation Potential: Characterization and Protein Engineering

“…Other than that, PPOs have been used as biocatalysts in many reactions, with various applications in food, pharmaceutical, and cosmetic industries ( 28 , 29 ) and also as biosensors for the detection of small amounts of phenolics in contaminated waters ( 30 ). Furthermore, they have shown potential in the bioremediation of wastewaters containing phenolic contaminants and for the reduction of chemical oxygen demand ( 28 , 31 , 32 ). As recently reviewed, although laccases have been widely studied, the class of tyrosinases remains underinvestigated, especially concerning its application in the bioremediation of phenolics ( 33 ).…”

Purification and immobilization of laccase from Trichoderma harzianum strain HZN10 and its application in dye decolorization

“…Immobilized enzymes have gained popularity due to several advantages like enzyme recovery, increased stability and durability, rapid enzyme separation from the reaction mixture, tolerance to extreme pH, temperatures and high substrate concentrations [14], [15], [16]. Various techniques like surface binding, gel entrapment (hydrogel), entrapment in reverse micelles, covalent and cross-linking bonding between an enzyme and matrix have been commonly used for improvement in the operational stability of enzymes [17].…”