Isolation and identification of Monascus and evaluation of its selenium accumulation

Abstract

Selenium (Se) plays an important role in human physiological metabolism. Se-enriched microorganism could be a remedy for Se-deficiency related diseases. Monascus are acid-resistant, saprophytic, filamentous and edible fungi which are widely used in the food fermentation industry. However, studies on Se-biofortification almost ignore the possibility of applications in Monascus. In this work, a Monascus purpureus, M12 was isolated from the collected samples and used for Se-resistant testing and Se-enrichment domestication. The results showed M12 hold strong ability to tolerate exogenously applied inorganic Se. At all concentrations of sodium selenite, the strain can enter the growth boom period within 2 d, without a lag period. The total selenium content in M12 was between 1400 and 2000 μg/g. When the concentration of sodium selenite was between 40 and 90 μg/mL, the utilization rate of inorganic Se reached 99%. The optimal conditions for Se accumulation were also optimized by determining the total Se, organic Se content in fungal cell. The Se enrichment ability of Monascus provides a new potential for dietary Se supplementation.