Biochemical changes in substrates during the growth of oyster mushroom

Abstract

Pleurotus sajor-caju was cultivated on paddy straw to evaluate the changes in the nutritional composition of the spent mushroom substrate (SMS). The analysis revealed an increase in protein (4.15–5.50%), ash (10.45–11.65%), and moisture (6.25–8.40%) contents, accompanied by a decrease in pH (6.90–5.30), crude fiber (34.25–18.10%), total carbohydrates (70.10–47.25%), lignin (21.15–7.20%), cellulose (42.25–24.85%), and hemicellulose (29.75–15.80%) contents in SMS compared to untreated paddy straw. During the vegetative phase (spawn run), lignin degradation occurred more rapidly, whereas during fructification, its degradation rate slowed while the breakdown of cellulose and hemicellulose accelerated. These findings indicate that treatment of paddy straw with P. sajor-caju significantly altered the chemical composition of the substrate by increasing its protein content and reducing lignocellulosic fractions, thereby enhancing digestibility and improving the potential feeding value of the resulting SMS as a feed.