ABSTRACT
The by-product left behind after harvesting the fruiting bodies of mushrooms from its substrate is known as a spent mushroom substrate or SMS in short. Each year, the mushroom-producing business worldwide generates a billion of tonnes of the discarded mushroom substrate. Only 1% of it is recycled, and the rest remains unused and could be detrimental to the environment. In addition, it would cost a lot of money to dispose of it properly. SMS is a highly useful by-product since it is enriched in vital secondary metabolites, minerals, proteins, carbohydrates, and organic materials. An eco-friendly approach to recycling used mushroom substrates is to convert them into sustainable value-added products like mycelial-based biomaterials, biofertilizers, animal feed, bio-sorbents and biocontrol agents. SMS is generated as a result of the cultivation of a variety of edible mushroom species on a wide range of lignocellulosic substrates including paddy straw, wheat straw, sugarcane bagasse, corn cobs and leaf litter which are also considered hazardous pollutants to the environment. Mushrooms of different genera including the white rot group, such as Ganoderma, Pleurotus and Schizophyllum have robust potential to decompose these lignocellulosic substrates and convert them into spent mushroom substrates with versatile properties and applications. The present review discusses the present status and future prospects of these valuable products along with potential applications.
