Araucaria angustifolia seed coat waste reduction through its utilization in substrate diversification for Pleurotus djamor production

Mushrooms of the genus Pleurotus are the second most cultivated and consumed variety worldwide due to their nutritional profile and the efficient use of agricultural and forestry residues as substrates. In order to explore the efficiency of seed coat lignocellulose from Araucaria angustifolia (pine nut) seeds (PSC) as a substitute substrate (20 %, 40 %, 60 % or 80 %) of Eucalyptus sawdust for the production of Pleurotus djamor (PD) was estimated the number of fruiting bodies (NFB), biological yield (BY), biological efficiency (BE), and nutritional and mineral composition. The PSC was separated from the almond seed, dried, ground and used as an alternative substrate (0–80 %) to Eucalyptus sawdust (400 g), which was mixed with wheat bran (97 g) and CaCO3 (3 g). Due to a higher Carbon/Nitrogen ratio of a PSC substrate, it was better compatibility for a fungal enzymology of PD mushroom than E. urograndis sawdust substrate. The substrate enriched with 40 % PSC exhibited elevated ash content (minerals) and reduced moisture levels, higher carbon/nitrogen ratio, optimal conditions for NFB, and increased BY and BE. PD showed significant levels of dietary fiber and essential elements, including Cu, Fe, P, Mn, Mg, and Zn, with minimal fat content. Araucaria angustifolia waste reduction through its utilization in substrate diversification for PD production brings about favorable environmental and societal outcomes, improving both the mushroom yield and their nutritional content. This approach serves as an environmentally sustainable solution for pinhão seed coat waste and should be encouraged and extended for broader use.