Extracting valuable compounds from straw degraded by Pleurotus ostreatus

This work aims to recover lignocellulosic waste in an environmentally friendly process, as an alternative to the energy-intensive technologies: steam explosion, subcritical and/or supercritical water treatment, decomposition through pyrolisis, etc.The study assesses the optimum of potentially valuable compounds from straw degraded by the fungus Pleurotus ostreatus. The effects of solvent nature, temperature and extraction time were quantified by material balances with a special view to the extracts obtained. Confirmation of the effectiveness of the operations was done by spectrophotometric, HPLC and LC–MS analyses.Following this study, a farm-based technology was tentatively conceived, requiring neither special skills nor special utilities, to obtain a semi-product for further processing. A centralised technology could be also taken into account to process the straw by direct extraction with hot solvents, in order to obtain products yields three times higher than in the case of the aqueous extraction followed by solvent extraction at 20 °C.

► Extracting low molecular weight chemicals from lignocellulosic material degraded by fungi.
► Extraction of water soluble compounds favored by increasing temperature.
► Best extraction yields when using solvent mixture ethanol/dichloromethane.
► Ambient temperature solvent extraction for an environmentally friendly process.