Extrusion and solid-state fermentation with <i>Aspergillus oryzae</i> on the phenolic compounds and radical scavenging activity of pecan nut <i>(Carya illinoinensis)</i> shell

Purpose Solid-state fermentation (SSF) has been highlighted as an alternative to obtain valuable compounds using agro-industrial wastes a substrate. The present study evaluated the impact of extrusion combined with SSF on production phenolic and their antioxidant activity pecan nut shell (PWS) Design/methodology/approach PWS extruded (PWSE) were fermented for 120 h at 30°C Aspergillus oryzae ( A. oryzae) . Samples withdrawn from incubator 6 h, 12 then every until fermentation. PWSE samples extracted. total content (TPC) radical scavenging (RSA) extracts characterized resulting extracts. Findings use yielded higher biomass rate after (PWS 75.74% vs 87.50%). In general, TPC RSA increased time. However, significantly p &lt; 0.05) values in comparison nonextruded PWS. Condensed tannins showed different trends depending Overall, results that pretreatment joint represents good raise antiradical lignocellulosic materials such PWSs. Originality/value This offers information may be used by walnut industry valorize coproduct substrate produce functional ingredients or fungal enzymes.