Fungi and Circular Economy: Pleurotus ostreatus Grown on a Substrate with Agricultural Waste of Lavender, and Its Promising Biochemical Profile

Abstract

The increasing production of essential oils has generated a significant amount of vegetal waste that must be discarded, increasing costs for farmers. In this context, fungi, due to their ability to recycle lignocellulosic matter, may be used to turn this waste into new products, thus generating additional income for essential oil producers. The objectives of our work, within the framework of the European ALCOTRA project FINNOVER, were two-fold. The first was to cultivate Pleurotus ostreatus on solid waste of lavender used for essential oil production. The second was to provide, at the same time, new products that can increase the income of small and medium farms in the Ligurian Italian Riviera. This paper presents two pilot tests in which P. ostreatus was grown on substrates with five different concentrations of lavender waste, ranging from 0 to 100% (w/w). Basidiomata grown on all the substrates and their biochemical profiles were characterized using high-performance liquid chromatography coupled to mass spectrometry. The biochemical analysis of mushrooms proved the presence of molecules with antioxidant and potential pharmacological properties, in particular in mushrooms grown on lavender-enriched substrates. The results open the possibility of producing mushrooms classified as a novel food. Furthermore, the results encourage further experiments aimed at investigating how different substrates positively affect the metabolomics of mushrooms.