Improvement of Ergone Production from Mycelial Culture of Polyporus umbellatus

Ergone, a fungal metabolite derived from ergosterol, was previously isolated and identified from Polyporus umbellatus. Ergone is a major component of P. umbellatus known to have anti-aldosteronic diuretic effect and also displays cytotoxic activities. Most of mushroom's fruit bodies used for test contained less than 10 ${\mu}g/g$ of ergone. But P. umbellatus have larger amount of ergone than any other mushrooms. In order to improve the ergone production from the submerged culture of P. umbellatus, several factors including medium composition, culture conditions (temperature and pH) and different combinations of co-cultivation with various mycelia were studied. Among various carbon sources examined, starch proved to be most effective for the production of mycelia. The optimum pH and temperature for a flask culture of P. umbellatus mycelia were found to be 4.5 and $25^{\circ}C$, respectively. Under the optimized culture conditions, both the ergone production (86.9 ${\mu}g/g$) and mycelial growth (3.5 g/l) increased when P. umbellatus was cultured with Armillariella mellea. When the optimized conditions were applied, both mycelium and ergone production were significantly enhanced.