Cultivation of two Pleurotus species on wheat straw substrates containing olive mill waste water

Olive oil extraction produces large amounts of waste water, known as olive mill waste water (OMWW). This has a high chemical oxygen demand and contains high levels of phenolic compounds, and is therefore a cause of environmental pollution. The major aim of this study was to investigate the use of OMWW as a moisture source for mushroom cultivation. Pleurotus sajor-caju and P. cornucopiae var. citrinopileatus were grown on wheat straw substrate moistened with different OMWW:tap water mixtures. In terms of mycelial growth, time for initiation of primordia and crop yield, substrate moistened with mixtures containing 25% and 50% OMWW was found to be suitable for cultivation of both organisms as compared with control medium which contains tap water as a moisturiser. However, moistening with a mixture containing 75% OMWW or with OMWW alone was not compatible with cultivation of these organisms.