UV-irradiated mushrooms as a source of vitamin D2: A review

Background: The deficiency of vitamin D has been widely reported all over the world and linked to several chronic diseases. Mushrooms are valuable nutritional foods with recognized bioactive properties, leading the application of UV irradiation to the production of significant amounts of vitamin D-2. In this context, cultivated species such as Agaricus bisporus, Lentinula edodes and Pleurotus ostreatus have been widely studied. Scope and approach: However, there is still gap considering the knowledge of the most appropriate irradiation procedures (dose, intensity, distance between source and sample, exposure time) in order to maximize the content of vitamin D-2 in the mushrooms. This strategy will enable vitamin D-2-enhanced mushrooms to be commercially available at affordable costs. Considering the interest and potential of application, this review mentioned some of the physiological roles and sources of vitamin D, while the major focus was on mushroom's UV irradiation as a source of vitamin D-2. Also, topics related to its bioavailability and clinical studies evidencing the health benefits reported so far were also addressed. Key findings and conclusions: UV-irradiated mushrooms present a high rate of conversion from ergosterol to vitamin D-2 at short treatment time and have the potential to increase serum 25-hydroxyvitamin D levels. Even though irradiated mushrooms exhibit some promising advantages, there is still a huge knowledge gap to allow for extraction, separation, recovery and purification of vitamin D-2 from irradiated mushroom at minimal process cost and high purity percentage to be utilized as bio-based ingredient to reduce vitamin D deficiency as well as present other health promoting benefits.