Impact of the natural resource of UVB on the content of vitamin D2 in oyster mushroom (Pleurotus ostreatus) under subtropical settings

Vitamin D deficiency is a pandemic problem. Non-animal source of vitamin D is obtained from edible mushrooms. Oyster mushroom (Pleurotus ostreatus) was sliced into the size of 1 cm(3), 4 cm(3) and 9 cm(3), and treated with the sun as a natural resource of UVB under subtropical settings in Ethiopia. The content of vitamin D was measured by using high-performance liquid chromatography (HPLC). After sun treatment, there was a significant increment in the content of vitamin D-2 from nil to 67.4 +/- 28.0 mu g/g dry weight (DW). Based on the results of the overall pairwise comparisons, 1 cm(3) size of slice group had the highest content of vitamin D-2. Duration of sun exposure, sizes of mushroom slices and moisture content were identified as determining factors for vitamin D-2 synthesis. Exposing slices of oyster mushroom to the sunlight for <30 min provides the amount that satisfies the current recommended dietary allowance (RDA) of vitamin D without any visible change in color and texture. Thus, sun treatment of oyster mushroom is an effective and economically cheap strategy in the fight against vitamin D deficiency. (C) 2018 Production and hosting by Elsevier B.V.