Change in Concentration of Vitamin D 2 in Oyster Mushrooms Exposed to 254nm and 365nm UV-light During Growth

Abstract

The sun emits ultraviolet radiation in form of ultraviolet-A (UV-A), ultraviolet-B (UV-B), and ultraviolet-C (UV-C) bands. Ultraviolet light has the potential to boost vitamin D 2 production in mushrooms which human bodies cannot synthesize. The ergosterol in mushrooms, a component of fungal cell membranes which serves the same function as cholesterol in animal cells, can be converted into vitamin D 2 by exposure to controlled ultraviolet light. However mushrooms are conventionally grown in the dark, necessitating artificial ultraviolet irradiation. This study investigated the effects of UV-A (365nm) and UV-C (254nm) light exposure time during mushrooms growth, on the concentration of vitamin D 2 in oyster mushrooms (Pleurotus ostreatus species) after harvest. Mushrooms samples exposure times were varied from 10-60 minutes per day at intervals of 10 minutes, and irradiation done for three days. UV spectroscopy was used to determine the amounts of Vitamin D 2. It was found that the absorbance of vitamin D 2 for UV-A light ranged from 0.18-0.49 for the 10-60 minutes of irradiation respectively, while for UV-C light the vitamin D 2 content absorbance was 0.38-0.81 for the 10-60 minutes of irradiation respectively. There was a linear relationship between time of irradiation and absorbance vitamin D 2 content up to 50 minutes for UV-A and 40 minutes for UV-C.