LED light spectra influence the stimulation of mycelial growth and anticancer activity in Hericium erinaceus mycelium

Hericium erinaceus is a medicinal mushroom known for producing diverse bioactive metabolites with therapeutic potential. However, cultivation strategies aimed at enhancing both fungal yield and metabolite bioactivity, particularly through light-mediated physiological modulation, remain insufficiently investigated. This study explored the influence of different LED light spectra on the growth performance and cytotoxic potential of H. erinaceus mycelia cultivated on a nutrient-rich red sorghum substrate.

Mycelia were cultivated for 30 days under four LED light spectra-blue, red, green, and RGB, compared to a control treatment (which was kept in darkness). Growth parameters, including radial growth rate, colonization speed, fresh weight, biomass increase, and mycelial density, were recorded at harvest. Ethanol extracts prepared from the mycelia of each treatment were tested for cytotoxic activity against SW480 colorectal cancer cells, HepG2 liver cancer cells, and normal colon epithelial cells (CCD-841 CoN), and IC₅₀ values were determined.

Blue light produced the most pronounced enhancement in growth performance, yielding the highest mycelial density (0.344 g/cm²), fresh weight (6.75 g), and biomass increase (12.28%), along with the fastest radial expansion and substrate colonization. Extracts from blue light-treated mycelia showed the strongest cytotoxic effects against SW480 (IC₅₀ = 133.71 μg/mL) and HepG2 cells (IC₅₀ = 114.84 μg/mL), while exerting minimal effects on normal CCD-841 CoN cells. These findings suggest that targeted light spectra can modulate fungal physiology, likely via photoreceptor-mediated pathways, to enhance both agronomic performance and production of cytotoxic metabolites. This study provides a framework for optimizing H. erinaceus cultivation for functional food and therapeutic applications.