Taguchi Optimization, Purification, and Characterization of laccase enzyme from Aspergillus niger

Ar Habib ,So El-Azab ,Am Gaber ,Sms Abo-El-Souad ,Mh Omar ,Ne Taha ,Mohamed N Abd El-Ghany ,Ha Abd El-Star ,S.s Wahba

doi:10.35495/jbra.2020.01.06

Abstract

Laccases are oxidoreductases enzymes that belong to blue multi-copper oxidases. In the recent years, laccases have gained application in the field of textile, pulp and paper, and food industries. In this work, optimization of cultural conditions of the fungal species Aspergillus niger was performed by Taguchi orthogonal array statistical method to enhance laccase production. The crude extract was precipitated by ammonium sulphate, purified by ion exchange column of sephadex G-100. The molecular weight of the purified laccase identified by SDS-PAGE was 135 kDa. The highest activity of purified laccase was obtained at enzyme concentration of 0.054 mg/ ml, substrate concentration of 2 mmol/L, temperature of 30?C and pH of 5.6. In addition, copper sulfate exhibited the highest significant promoted effect on laccase activity, while zinc sulfate caused almost its complete inhibition.

Highlights

Aspergillus niger to enhance laccase production by using Tagaushi statistical method To maximize the yield of laccases, eighteen separate media were cultivated with tested fungi
Tagaushi provides ANOVA model (Figure-1) which submitted that model is significant, the significant factors which effect on laccase production are sucrose and agitation and these factors known by two values
Characterization of the purified Aspergillus niger laccase in our study revealed that the maximum activity of laccase was obtained at temperature 30 ̊C

Summary

Introduction

Laccases (benzene diol: oxygen oxidoreductases, EC1.10.3.2)are effective enzymes that represent the largest subgroup belonging to the multi-copper oxidases category of enzymes (Hilde et al, 2009; Claus and Strong, 2010; Sahay et al, 2019).Laccases are abundant in nature and they can be found in many bacteria, arthropods, higher plants, some insects and especially in fungi.Fungal laccases are assumed to participate in different physiological functions such as the development of the fruiting body, pigmentation, sporulation, pathogenesis, and copper homeostasis (Kues and Liu, 2000; Zhu et al, 2001; Holker et al., 2002; Rivera-Hoyos et al, 2013) besides, their role in the degradation of lignin and plant litter decay processes (Kellner et al, 2007; Liers et al, 2011).The wide variety of fungal laccases have been isolated from basidiomycetous, ascomycetous and deuteromycetous (Giardina et al 2010; Singh and Gupta, 2020). Laccases are abundant in nature and they can be found in many bacteria, arthropods, higher plants, some insects and especially in fungi. Fungal laccases are assumed to participate in different physiological functions such as the development of the fruiting body, pigmentation, sporulation, pathogenesis, and copper homeostasis (Kues and Liu, 2000; Zhu et al, 2001; Holker et al., 2002; Rivera-Hoyos et al, 2013) besides, their role in the degradation of lignin and plant litter decay processes (Kellner et al, 2007; Liers et al, 2011). The wide variety of fungal laccases have been isolated from basidiomycetous, ascomycetous and deuteromycetous (Giardina et al 2010; Singh and Gupta, 2020). Aspergillus sp. have the ability to produce laccase as Aspergillus niger (Ramos et al., 2011), Aspergillus flavus (Ali et al 2015), Aspergillus nidulans

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Discussion

Conclusion