Optimization and recovery of vitamin D2 from surplus production of Agaricus bisporus Portobello. Rossana V. C. Cardoso, Ângela Fernandes, João C. M. Barreira1, Rui M. Abreu, Filipa Mandim, Ana M. Gonzaléz-Paramás, Isabel C.F.R. Ferreira, Lillian Barros.