Marium Begum, Subhankar Ghosh and Siddhartha Proteem Saikia,
Abstract
Vitamin D is a fat-soluble vitamin that plays an important role in calcium absorption from the intestinecontributing to bone health and many other functions leading to health improvement. There are mainlytwo forms of Vitamin D, namely Vitamin D3 (Cholecalciferol) and Vitamin D2 (Ergocalciferol). Ergocalciferol(Vitamin D2) is a form of Vitamin D found in food, especially mushrooms. Mushrooms contain ergosterolin their cell membrane; exposure to sunlight/ultraviolet (UV) light causes a photochemical reaction thatisomerizes ergosterol to Vitamin D2. Mushrooms are extensively grown in North-East India from timeimmemorial by the ethnic people. In this study, Vitamin D2 from fruiting bodies of two Oyster Mushroomspecies, namely Pleurotus florida and Pleurotus cornucopiae, is quantified using a spectrophotometer at 264nm.This study aimed to determine the Vitamin D2 accumulation potential of both the species and to select thebest species with the highest Vitamin D2 accumulation potential. Fresh cultures of P. florida and P. cornucopiaewere maintained in CSIR-North East Institute of Science &Technology (CSIR-NEIST) Mushroom GermplasmUnit, Jorhat, Assam, India and cultivated in the cultivation unit. A total of 24 treatments were given to eachsample by exposing it to UV rays ranging from UV-A (365nm and 395nm) and UV-B (280nm and 310nm)for different time periods. It was observed that Vitamin D2 levels varied with different wavelengths used.In both the species, Vitamin D2 levels increased in the UV-B range than in the UV-A range. Moreover,between the two species under study, P. florida showed the highest Vitamin D2 accumulation potential at280nm when exposed for 120 minutes. The level of Vitamin D2 increased to an optimum level at 120 minutesof UV exposure and then declined upon the increase in the time period. The recommended daily allowanceof Vitamin D is 400-800 IU/day according to WHO. In this study, post-UV treatment, the Vitamin D2 levelsdrastically increased to a range of 1000-6000 IU approximately which is safe and can be used in thepreparation of Vitamin D supplements in future.