Stimulation of mycelia growth in several mushroom species by rice husks.

When supplemented to the culture medium of mushroom Coprinus cinereus, rice husks soaked beforehand in methanol stimulated mycelia growth up to a concentration of 80 mg/ml dose-dependently, whereas the non-treated stimulated mycelia growth up to 20 mg/ml. This result suggests the existence of both stimulatory and inhibitory substances in rice husks. Since momilactone A (MLA) is recognized as one of the phytoalexins in rice husks, its biological activity against mycelia growth was tested.