Valorization of Ginkgo biloba Leaf Powder as a Substrate in King Oyster Mushroom (Pleurotus eryngii) Cultivation

Abstract

Ginkgo biloba is widely planted as a colorful foliage tree, and its leaf can be used as a biomass energy source, but it has been underutilized for a long time. The aim of this study was to investigate the potential of garden waste as a substrate component in the cultivation process of the king oyster mushroom (Pleurotus eryngii), with the goal of enhancing both the yield of P. eryngii and the efficiency of energy use. The percentages of G. biloba leaf powder in the substrate were 10.5% and 21% to replace sawdust or sugarcane bagasse in a typical substrate. A substrate formulation that could completely replace sawdust and sugarcane bagasse was selected by analyzing mycelial growth rate, days of production, fruiting body length, biological efficiency, yield, stipe thickness, pileus diameter and laccase activity. The results showed that Y1 (treatment with 21% G. biloba leaf powder and sugarcane bagasse) had the highest yield (303.1 ± 31.9 g), which was higher than that of CK (control) (259.3 ± 37.4 g). The crude fiber content of the samples grown on substrate Y1 (as 7.43%) was higher than CK (7.37%). In addition, P. eryngii grown on substrate Y1 had the highest laccase activity for the complete colonization of the mycelium. Thus, these findings suggest that G. biloba leaf powder represents a viable and economical supplement for enhancing both the yield and quality of P. eryngii.