The Fruiting Body Formation of Oudemansiella radicata in the Sawdust of Oak (Quercus variabilis) Mixed with Rice Bran

Oudemansiella radicata (Relhan ex Fr.), one of edible and medicinal mushrooms belonging to Tricholomataceae, Agaricales has been known to be inhabited on the soil surface or rotted woods of the broad-leaved trees from summer to autumn (Lee, 1988). O. radicata has been collected occasionally in the remote sites of mountainous area of large parks in Korea (Kim et al., 2005). Also, fruiting body of O. radicata has been reported to possess oudenone which is one of medicinally important chemical compounds (Umezawa et al., 1973; Tsantrizos et al., 1999). The oudenone exhibited an outstanding therapeutic and inhibitory effect on the sarcoma 180 and Erhrlich carcinoma (Umezawa et al., 1973; Anke and Werle, 1990). In the submerged culture, O. radicata has been known to secrete oudemansin which exhibits high antifungal activities to plant pathogenic fungi such as Penicillium notatum, Ustilago nuda and Alternaria poli (Anke and Werle, 1990). Oudemansin was also produced from fruting body of O. mucida as well as O. radicata (Anke et al., 1979, 1983). Although O. radicata has been considered as one of the promising edible fungi (Umezawa et al., 1973; Anke and Werle, 1990; Tsantrizos et al., 1999), there was no an experiment for producing fruiting bodies of O. radicata in Korea. As part of preliminary experiment for realizing an artificial mass production of O. radicata, Kim et al. (2005) reported the optimal culture conditions such as temperature, pH, nutrients and culture media suitable for its mycelial growth. Therefore, this study was carried out to screen an additive suitable for the mycelial growth of O. radicata on sawdust media and to test if the additive could produce fruiting body of O. radicata.