Efficient Recovery of Lignocellulolytic Enzymes of Spent Mushroom Compost from Oyster Mushrooms, Pleurotus spp., and Potential Use in Dye Decolorization

Abstract

This study was conducted in order to perform efficient extraction of lignocellulolytic enzymes amylase (EC 3.2.1.1), cellulase (EC 3.2.1.4), laccase (EC 1.10.3.2), and xylanase (EC 3.2.1.8) from spent mushroom compost (SMC) of Pleurotus ostreatus, P. eryngii, and P. cornucopiae. Optimal enzyme recovery was achieved when SMCs were extracted with 50 mM sodium citrate (pH 4.5) buffer at 4℃ for 2 hr. Amylase, cellulase, and xylanase activities showed high values in extracts from P. ostreatus SMC, with 2.97 U/g, 1.67 U/g, and 91.56 U/g, respectively, whereas laccase activity and filter paper degradation ability were highest in extracts from P. eryngii SMC, with values of 9.01 U/g and 0.21 U/g, respectively. Enzymatic activities varied according to the SMCs released from different mushroom farms. The synthetic dyes remazol brilliant blue R and Congo red were decolorized completely by the SMC extract of P. eryngii within 120 min, and the decolorization ability of the extract was comparable to that of 0.3 U of commercial laccase. In addition, laccase activity of the SMC extract from P. eryngii was compared to that of commercial enzymes or its industrial application in decolorization.

Purification and Characterization of Xylanase from Spent Mushroom Compost and its Application in Saccharification of Biomass Wastes

“…The SMC extract of T. fuciformis showed the highest xylanase activity (39.3 U/mL) of with 1.1 U/mL of cellulase activity and 0.1 U/mL of laccase activity among the eight SMCs. The result represented 196.5 U/g T. fuciformis SMC for the xylanase activity, which was obviously higher than the xylanase activities of SMC extracts from the other reported mushroom species (Singh et al 2003;Lim et al 2013). The highest xylanase activity of 91.6 U/g Pleurotus spp.…”

“…In previous studies, the highest xylanase activity is 91.6 U/g SMC from Pleurotus spp. (Lim et al 2013). A possible explanation is that the concentration of xylanase in T. fuciformis SMC is higher or the xylanase from T. fuciformis SMC possesses high specific activity compared with that of other SMCs.…”

“…The highest xylanase activity of 91.6 U/g Pleurotus spp. SMC was achieved among previous studies (Lim et al 2013). Therefore, the SMC of T. fuciformis was selected for further experiments.…”

“…The disposal strategies of SMC include burning, spreading on land, burying, composting with animal manure, or landfilling (Singh et al 2003;Phan and Sabaratnam 2012). Recently, some studies used SMC as a raw material to produce value-added products such as biogas, bulk enzymes, and organic fertilizer by bioconversion and as animal feed supplements (Bisaria et al 1990;Soechtig and Grabbe 1995;Kumaran et al 1997;Lim et al 2013). New applications for SMC utilization would be economical and beneficial for human health and environmental protection.…”

Simulated Ammonia Nitrogen Wastewater Treated with Spent Mushroom Compost in a Laboratory Bioreactor

“…This matter, most of which was combined with the solids, was dissolved slowly with time elapsing, especially in the first 24 h. 2. It is well known that there are a certain number of extracellular enzymes in SMC (such as cellulase, xylanase, and ligninase) that have been purified from SMC by some researchers [11,[27][28]. These enzymes were active and could slowly hydrolyze those solid carbon sources to release solvable carbon sources.…”