Biofortification of Pleurotus geesteranus via exogenous selenium species: Selenium distribution, speciation and its effect on mineral elements accumulation

In this study, four Se species including selenite [Se (VI)], selenate [Se (VI)], potassium,2-selenocyanatoacetate (PSeCA), and selenium ore powder (SeOP) were used for biofortification of Pleurotus geesteranus to obtain Se-enriched mushroom. Based on their effects on mycelium growth of P. geesteranus Jinxiu, [Se (VI)] in the concentration range of 100-1000 μg/kg and other three Se species in the range of 100-2000 μg/kg were adopted in spawn running and fruiting body growth stage, with their effects on production yield and elements accumulation evaluated. The results revealed that PSeCA treatment (200 μg/kg) had the highest fruiting body production (290.61 g/bag), followed by 2,000 μg/kg of SeOP treatment (286.24 g/bag). SeMet revealed to be dominant species detected in mushroom, with [Se (VI)] exhibited the highest biological efficiency among the four Se species, and 2,000 μg/kg of PSeCA treatment exhibited the highest Se content (10.25 mg/kg) in terminal phase of fruiting body. The results suggested that high concentration of PSeCA would be more favored for the Se biofortification. Moreover, Se treatment could greatly alter the mineral elements content of fruiting bodies, both synergistic and antagonistic relationships on accumulation of mineral elements were observed for each tested Se species. • Four Se species were evaluated to biofortification of P. geesteranus mushroom. • PSeCA and SeOP significantly enhanced the production of fruiting bodies. • SeMet was the most abundant species under exogenous Se biofortification process. • Se treatments revealed great changes on bioaccumulation of mineral elements.