Optimizing growth, yield, and antioxidant properties of Pleurotus ostreatus M2191 and Pleurotus sajor-caju M2345 using industrial and agricultural waste substrates

Abstract

• Industrial and agricultural waste substrates optimize the growth and yield of Pleurotus species mushrooms. • Highest yields were achieved with cottonseed and potato peel-stinging nettle straw substrates. • Pleurotus ostreatus showed superior antioxidant properties across different waste-based substrates than Pleurotus sajor-caju . • Substrate type and season significantly influence mushroom yield, efficiency, and antioxidant activity. Edible mushrooms are gaining attention as a sustainable and nutritious food source with health benefits besides waste removal when cultivated on waste-based substrates. This study investigated the effects of various industrial and agricultural waste materials on the growth, yield, and antioxidant properties of two mushroom species: Pleurotus ostreatus M2191 and Pleurotus sajor-caju M2345. Substrates were formulated using industrial wastes (barley, malt, potato, and potato peel) and agricultural residues (cottonseed, wheat straw, and stinging nettle straw) with 8% wheat bran and 2% gypsum added. Growth trials were conducted in two seasons (1 st season January to March and 2 nd season May to July). From January to March, 75% potato peel and 25% stinging nettle straw substrate achieved the quickest colonization (18 days). The yield of P. ostreatus increased by nearly 100% in the second season, reaching 728.6 g compared to less than 400 g in the first season, while P. sajor-caju exhibited a 70 – 90% yield improvement. Biological efficiency varied significantly, with P. sajor-caju showing a range of 20.3 – 98.7% and P. ostreatus ranging from 22.8 – 97.7%, reflecting strain-specific and seasonal differences. Antioxidant activity was also season and strain-dependent, increasing by approximately 30 – 50% in the second season for most substrates, particularly in P. ostreatus . Substrate composition was a key determinant, where cottonseed enhanced yield and biological efficiency by more than 80% compared to stinging nettle straw, which completely inhibited growth. The substrate composition significantly affected yield, biological efficiency, and antioxidant activity in both species and growing seasons.