Production of cellulolytic enzymes via solid state fermentation of spent mushroom substrate by Trichoderma asperellum UPM 1

• Main Author: Mohd Ariff, Iffah Nabilah
• Format: Thesis
• Language: English
• Published: 2016
• Subjects: Mushrooms; Mushroom culture
• Online Access: http://psasir.upm.edu.my/id/eprint/75829/1/FBSB%202016%2044%20-%20IR.pdf; http://psasir.upm.edu.my/id/eprint/75829/
• Institution: Universiti Putra Malaysia

Spent mushroom substrate (SMS) is a by-product generated after mushroom harvesting from the commercial mushroom cultivation industry. SMS had lost a significant fraction of their mass (approximately 35-50% depending on their nature) due to metabolic reactions, mushroom production and water evaporation. SMS generally composed of three main components i.e. fungal mycelia, extracellular enzymes secreted during growing of mushroom and unutilized lignocellulosic components. Delignified SMS with small particle size (<1 mm) has been observed to have high cellulose component and lignocellulolytic enzyme content. SMS comprised of high cellulose (45.5%) and partially degraded lignin by the action of Pleurotus pulmonarius during mushroom cultivation. SMS in readily available smaller particle size offers a great advantage as a fermentation feedstock. Hence, owing to this untapped potential, this study has investigated the feasibility of SMS as an alternative substrate for lignocellulolytic enzyme recovery. This was done by profiling ligninolytic enzymes activities produced during the growth of P. pulmonarius and P. floridanus. Crude laccase (3 U/g and 2.6 U/g) and MnP (1.4 U/g and 2.1 U/g) were detected in SMS from P. pulmonarius and P. floridanus, respectively. After enzyme recovery, optimization of cellulase production from SMS as a feedstock was conducted using Central Composite Design (CCD). Cellulase was produced on SMS from P. pulmonarius via solid state fermentation using Trichoderma asperellum UPM 1. Significant parameters of temperature, moisture content, and pH employed at three different levels were highlighted and discussed. The optimum condition for maximum production of CMCase (171.21 U/g), FPase (9.85 U/g) and β-glucosidase (6.83 U/g) were as follows; temperature 27.5ºC, moisture content 81% and pH of fermentation 4.5. The optimized condition of cellulase production resulted in increment of 1.4-fold in CMCase and 1.5-fold in β-glucosidase with unoptimized condition produced 125.77 U/g CMCase and 4.67 U/g β-glucosidase.