Stimulation of growth, polysaccharides, and triterpenoids formation in antler-type fruiting body of Ganoderma sichuanense using light-emitting diodes

Abstract

The Ganoderma mushrooms are known for their abundance of various bioactive substances, such as triterpenoids and phenolic compounds. The accumulation of these substances in mushrooms can be enhanced by light exposure. This study aimed to enhance the production of bioactive compounds and antioxidant activity in G. sichuanense using light-emitting diode (LEDs) irradiation. To achieved this, the mushroom was cultured in plastic bags under different wavelengths, including red (620–645 nm), green (515–545 nm), blue (450–460 nm) or white (380–760 nm) and light intensities (1, 3, 10 or 20 µmol m^{− 2}s^{− 1}). The results showed that the optimum light intensity for growing fruiting bodies was 10 µmol m^{− 2}s^{− 1} under blue light, resulting in the highest yield, polysaccharide content, and triterpenoid content of 15.62%, 82.44 mg g^{− 1} mushroom, and 11.64 mg UA g^{− 1} mushroom (p ≤ 0.05), respectively. Fourier Transform Infrared Spectroscopy (FTIR) identified the functional group features of the bioactive compounds obtained from cultivation under different light wavelengths. LEDs light also stimulated the production of phenolic compounds and antioxidants in the mushroom, as detected by DPPH radical-scavenging activity (31.46−42.96%). Consequently, LEDs irradiation can be regarded as a practical and effective approach for cultivating antler-type fruiting bodies of G. sichuanense, resulting in a beneficial impact on the increase of important bioactive compounds that can be used in various applications, including functional food ingredients.