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

Abstract

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.