Isolation and identification of Vitamin D2 photobyproducts in irradiated white button mushrooms

Abstract

Vitamin D, the sunshine vitamin, has been long known to be crucial for bone health and more recently it has been discovered to reduce the risk for cancer and several chronic diseases. Unfortunately, vitamin D deficiency affects millions of people worldwide. Therefore, vitamin D supplementation and sensible sun exposure have become more important than ever. Mushrooms are a well-known source of supplementation because of their high concentration of vitamin D's precursor, ergosterol. Irradiation of mushrooms has become popular with the mushroom industry in order to fortify their products with vitamin D. Limited research has been conducted in the kinetics of previtamin D2's conversion to vitamin D2. The goal of this research is to help identify the kinetics of the conversion of previtamin D2 to vitamin D2 in irradiated white button mushrooms (Agaricus bisporus). Mushrooms and ampoules containing ergosterol were irradiated with a RC-500B Pulsed UV Curing System (Xenon Corporation, Woburn, MA) and extracted with 100% methanol. Samples were dried under an N2 stream, and prepared for HPLC. A Zorbax RX-SIL column, and CN column, were used to separate the photobyproducts of previtamin 02, lumisterol, tachysterol and vitamin D2. Photoproducts of previtamin D2 were exposed to room temperature (25° C) and studied with respect to time. A 24 hour time course was conducted, and concluded there to be a statistically significant difference (P less than 0.001) in the conversion of previtamin D2 to vitamin D2 in mushrooms and ampoules at 0 hours and between 6 and 24 hours.