Chitosan multiple addition enhances laccase production from Trametes versicolor

Abstract

Chitosan multiple addition strategy was developed to improve laccase production from Trametes versicolor cultures. The optimized multiple addition strategy was carried out by two-time addition of 0.1 g L -1 chitosan to a 2-day-old culture media, with 24-h interval between the treatments. Under these conditions, laccase activity of 644.9 U l -1 was achieved on the seventh day and laccase production was improved by 93.5 % higher than the control. Chitosan treatment increased reactive oxygen species generation and extracellular protein concentration in the treated mycelia. In contrast, the inducer inhibited the mycelia growth. The result of the quantitative reverse transcription polymerase chain reaction showed that the copy number of the laccase gene transcript increased by 16.7-fold in the treated mycelia relative to the control. This study provides insight into some of the intrinsic metabolic processes involved in the upregulation of laccase production in the presence of chitosan inducer in fungal culture.

β-Carotene from Yeasts Enhances Laccase Production of Pleurotus eryngii var. ferulae in Co-culture

“…Enhancement of fungal laccase production after adding an antioxidant represented a response to oxidative stress, which was caused by oxygen radicals generated by inducers (Thurston, 1994; Wang et al, 2014). A higher concentration of intracellular reactive oxygen species (ROS), including superoxide anion (O 2 - ), hydrogen peroxide (H 2 O 2 ) and hydroxyl radical (OH-), has been reported to enhance both laccase production and transcription, depending on the activation of signal transduction and the oxidative stress (Adekunle et al, 2015; Hu et al, 2016). H 2 O 2 participated in the activation of the mitogen-activated protein kinase (MAPK) and cyclic adenosine monophosphate (cAMP) pathways (Calvo et al, 2002; Cap et al, 2012).…”

“…Besides genetic engineering technology, enhanced laccase production has also been achieved by optimizing the culture medium (Dekker et al, 2007), especially by adding inducers. Some researchers have focused on screening for effective inducers, and laccase production in Trametes versicolor has been effectively improved by farnesol and chitosan (Adekunle et al, 2015; Hu et al, 2016). Different inducers enhance laccase production by various mechanisms, including the improvement of silent or poorly expressed laccase isoforms and the response to oxidative stress caused by an inducer (Hoegger et al, 2006; Wang et al, 2014).…”

Comparative mitochondrial genome analysis reveals intron dynamics and gene rearrangements in two Trametes species

“…Their efficient lignin decomposition ability makes Trametes important decomposers in ecosystems and plays an important role in the natural cycle of earth forest ecosystems. In addition, Trametes species have also been used in ex situ and in situ biosynthesis and bioremediation studies [3][4][5][6] . A series of lignin-degrading enzyme systems and genes have been found to be closely related to the excellent degradation ability of Trametes 7-9 , including lignin peroxidases, manganese peroxidases, and laccases.…”