The effect of UV light on the Vitamin D content and mycelial growth of oyster mushroom

Vitamin D2 is essential for maintaining the proper functioning of a human body, and to prevent and help cure various diseases. Mushrooms are one of the few natural sources of vitamin D. Many experiments aimed to increase the vitamin D level of cultivated mushrooms, by irradiating them with UV light to turn their ergosterol content into vitamin D. The subjects of most of these studies were post-harvest sliced or whole mushrooms. Our goal was to treat pre-harvest oyster mushroom with UV light, while the mushrooms are still growing and biologically active. UV lamps (operating on 254 and 312 nm) and 6 time periods of irradiation (15 to 90 minutes) were used. After three consecutive days of treatments the yield were measured and samples were taken for vitamin D2 analysis. A parallel, in vitro experiment took place in the laboratory as well, where the same treatments (wavelengths and irradiation times) were applied on the tissue cultures of the same oyster mushroom cultivar used in the in vivo experiment. The mycelia growth was measured in case of all treatments. Data showed considerable increase in vitamin D2 levels of the treated oyster mushrooms at every time period. UV irradiation caused no change in yield, but affected the growth of the in vitro tissue cultures significantly.