Bio-Recycling Hazelnut Shells to Improve Antioxidant Properties of Lentinus tigrinus Sporophore

Lentinus tigrinus is a wood-decay fungus known for its nutritional, culinary, and medicinal benefits. It contains bioactive compounds like polyphenols, terpenes, and flavonoids that exhibit antioxidant, anti-microbial, and anti-inflammatory effects. These natural antioxidants are increasingly recognized for their potential to prevent oxidative damage linked to aging and chronic diseases. This study investigates the antioxidant activity of hydroalcoholic extracts obtained from L. tigrinus sporophores cultivated on hazelnut shells (Lt1_HS), a waste material rich in phenolic compounds, and sporophores cultivated on sawdust (Lt1_S). Bioactivity tests, including DPPH, TBARS, MTT, and DCFH-DA assays, were performed to assess the hydroalcoholic extracts’ efficiency. The results showed that all the extracts contained various bioactive compounds, primarily polyphenols. Notably, the caffeoylquinic acids present in HS and Lt1_HS are linked to anti-peroxidant effects. Biological analyses demonstrated that the Lt1_HS extract has higher anti-peroxidant activity (IC50 0.77 ± 0.01 mg/mL) compared to Lt1_S (IC50 1.36 ± 0.01 mg/mL) and reduces the accumulation of reactive oxygen species in HaCaT cells by 80%. However, the specific bioactive compounds responsible for these antioxidant effects are still unclear, and further analysis will be conducted. Additionally, this study promotes recycling hazelnut shells as a valuable substrate for fungal cultivation, supporting sustainable waste management.