The effect of various inducers and their combinations with copper on laccaseproduction of Trametes versicolor pellets in a repeated-batch process

Abstract

Introduction Laccases(EC 1.10.3.2, p-diphenol:dioxygen oxidoreductases) are industrially important multicoppercontaining enzymes. Although laccases are produced by some higher plants, insects, bacteria, and fungi, these enzymes are mainly abundant in white rot fungi (Gochev and Krastanov, 2007;Shraddha et al., 2011). These fungi, including Trametes, Pleurotus, Coriolopsis, and other genera, produce laccase enzymes at varying rates (Tapia-Tussell et al., 2011). Trametes is one of the most effective laccase-producing genera (Jang et al., 2002;Rosales et al., 2007). Fungal laccases are generally extracellular and they catalyze the oxidation of a wide range of compounds, such as mono-, di-, and polyphenols, aminophenols, methoxyphenols, aromatic amines, ascorbate, and nonphenolic compounds (Thurston, 1994;Couto et al., 2002;Baldrian, 2006;Patel and Gupte, 2016). The nonnecessity of any extraction process for obtaining these enzymes and their low substrate specificities make laccases suitable for many industrial applications, such as pulp delignification and biobleaching, textile dye decolorization, wastewater treatment, fruit juice processing, and construction of biosensors and biofuel cells (Minussi et al., 2002;Giardina et al., 2010;Durán et al., 2014;Yeşilada et al., 2014). Due to their broad industrial and environmental uses, these enzymes have gained increasing attention. Laccase production can be stimulated by various inductive substances, including metal ions, aromatic or phenolic compounds, alcohol, and detergents (Collins and Dobson, 1997;Birhanli and Yesilada, 2006;Tychanowicz et al., 2006;Bettin et al., 2014). Furthermore, inducer concentration, fermentation types, growth media, and incubation conditions have an important effect on laccase production and they are specific to species and strains (Boran and Yesilada, 2011). Many researchers have investigated the effects of various fermentation processes, cultivation conditions, laccase-producing organisms, and inducers on laccase production (

Laccase activity of the ascomycete fungus Nectriella pironii and innovative strategies for its production on leaf litter of an urban park

“…Among all the tested isolates, strains marked as IM 6443, IM 6467, and IM 6482 formed a dark green halo in ABTS-supplemented plates, while 2,6-DMP oxidation expressed by the formation of an orange halo was shown by the strains IM 6443 and IM 6482. Screening of laccase-producing microorganisms on solid media containing coloured indicator compounds is known to enable quick visual detection of laccase production; however liquid cultivations are necessary for the measurement of enzyme activity [9]. The laccase activity of the tested strains was estimated over the period of 6 days at regular intervals of 24 h under submerged fermentation conditions (Fig 2).…”

“…Increase of enzyme biosynthesis through modification of the culture medium composition, changing the processing conditions, and supplementation with chemical inducers, such as metal ions and aromatic compounds, is a well-known solution for this problem. However, few studies indicate synergistic stimulation of laccase production by metal ions and aromatic compounds [9,10]. Also, utilizing bio-waste to obtain an enzyme can reduce production cost while generating higher concentrations of products [11].…”

Enrichment of laccase production byPhoma herbarumisolate KU4 under solid‐state fermentation by optimizing RSM coefficients using genetic algorithm

“…1c). CuSO 4 was reported as the most efficient inducer for laccase production by Birhanli and Yeşilada (2017). Whereas, tannic acid was found as most promising inducer for laccase production by Yang et al .…”

Copper-induced Production of Laccases for Lignin Depolymerisation and Micropollutant Degradation by Laccase-mediator Systems

“…These elements indicate that more laccases were likely produced by the fungi. While other authors measured increased quantities of laccase mRNA [19,20] or increased laccase activities upon copper supplementation, [14,19,28] no study on the combined effect of copper on laccase activity itself and on its increased expression was published to our knowledge. Determining the threshold for the copper concentration required to increase laccase activity would conclusively shed light on this aspect and help determining the optimal copper concentration for laccase production.…”

“…Determining the threshold for the copper concentration required to increase laccase activity would conclusively shed light on this aspect and help determining the optimal copper concentration for laccase production. [27][28][29] Low peroxidase activity was also produced in the culture medium (Fig. 3B) with a maximum activity of 0.2 U/mL.…”