Assessment of Woody Lignocellulosic Substrates for Mycelial Colonization and Bio Composite Development Using Pleurotus ostreatus

Abstract

The increasing demand for sustainable and biodegradable alternatives to synthetic materials has accelerated research on mycelium-based composites using lignocellulosic biomass. This study evaluated the colonisation behaviour of Pleurotus ostreatus on selected woody substrates including subabul (Leucaena leucocephala), melia (Melia dubia), bamboo (Dendrocalamus strictus), eucalyptus (Eucalyptus tereticornis), lantana (Lantana camara), and ailanthus (Ailanthus excelsa) under controlled laboratory conditions. The substrates were processed to a particle size of approximately 8 mm, sterilised, inoculated with sorghum grain spawn at a 1:1 ratio, and incubated at 25°C and 75% relative humidity for 18 days. A comparative qualitative evaluation was conducted based on surface colonisation, internal mycelial spread, hyphal density, uniformity of growth, colour changes, and contamination occurrence. Among the tested substrates, subabul and melia exhibited excellent colonisation with dense and uniform mycelial growth (++++) and extensive substrate coverage. Bamboo showed good colonisation behaviour (+++) with comparatively stable mycelial spread, whereas eucalyptus and lantana exhibited sparse and uneven growth (+) with delayed colonisation and slight contamination. Ailanthus demonstrated moderate colonisation behaviour (++). The observed differences in fungal growth behaviour were attributed to variations in substrate composition, porosity, moisture interaction, and the presence of inhibitory extractives such as phenolic compounds and essential oils. The findings indicate that substrate characteristics influence fungal establishment and colonisation efficiency. The study highlights the potential of subabul and melia as promising woody substrates for future bio-composite development. Although the present investigation was preliminary, the results provide useful insights into substrate compatibility and sustainable utilisation of woody lignocellulosic biomass for environmentally friendly biomaterial applications.