INFLUENCE OF LOW-INTENSITY LIGHT ON THE BIOSYNTHETIC ACTIVITY OF THE MEDICINAL MACROMYCETE LARICIFOMES OFFICINALIS Laricifomes officinalis (Fomitopsidaceae, Polyporales) in vitro

Understanding the impact of artificial lighting on the biosynthetic and biological activity of medicinal mushrooms will help enhance technologies aimed at obtaining bioactive compounds. The aim of our work was to determine the influence of low-intensity quasi-monochromatic light on biosynthetic activity, including the antioxidant activity of the medicinal fungus Laricifomes officinalis under submerged cultivation conditions. Methods. The effect of light on the biosynthetic activity of L. officinalis was studied using sources of low-intensity coherent monochromatic laser light and quasi-monochromatic radiation of light-emitting diodes (LEDs) with specified spectral-intensity characteristics. Results. The most stimulating effect on the biosynthetic activity of the L. officinalis strain was observed when samples were irradiated with blue (488 nm laser and 470 nm LED) and red (650 nm LED) light. Under these conditions, there was an increase in the synthesis of mycelial mass, polysaccharides, and the quantity of total phenolic compounds. Low-intensity light irradiation caused changes in both the quantitative and qualitative composition of the fatty acid profile of the mycelial mass. Red light irradiation resulted in an increase in the quantity of polyunsaturated fatty acids. A correlation was established between the quantity of total phenolic compounds and antioxidant activity. Conclusions: The research results provide grounds to consider low-intensity visible light as a promising regulator of the biosynthetic activity of L. officinalis in the biotechnology of its cultivation.