著者

花井 秀俊 斉藤 千秋 石田 小百合 米田 哲也 草野 都 田母神 繁 野間 正名

出版者

植物化学調節学会

雑誌

植物化学調節学会研究発表記録集 (ISSN:09191887)

巻号頁・発行日

no.38, 2003-10-10

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When supplemented to culture medium of mushroom Coprinus cinereus, rice husks which had been soaked in methanol beforehand dose-dependently stimulated mycelia growth up to a concentration of 80mg/ml, but nontreated husks up to 20mg/ml. These results suggested the existence of both stimulatory (hydrophilic) and inhibitory (lipophilic) compounds in rice husks. As momilactone A (MLA) had been isolated as one of germination inhibitors in rice husks, its biological activity against mycelia growth was tested. Momilactone A inhibited the mycelia growth at a concentration of 1μg/disc. Methanol extract of the husks also inhibited at a concentration of 1mg/disc (corresponding to 0.2μg MLA/disc, by quantification with LC/MS/MS). Thus, lipophilic compounds such as MLA in rice husks, readily extractable with methanol (two days extraction at room temperature or over one hour reflux), should inhibit the mycelia growth. Aqueous extract of methanol soaked husks stimulated mycelia growth. Purification of the stimulatory compounds on ion exchange- and gel permeation columns followed by RP-HPLC is not enough to yield pure active principals. Rice husks also stimulated mycelia growth of Grifola frondose, Lentinus edodes, Pleurotus eriyngii and P. ostreatus as well as C. cinereus. Furthermore, they increased both the number and fresh weight of primordia and adult fruit body of P. eriyngii and P. ostreatus when supplemented to the medium.