Hypsizigus marmoreus (Buna-shimeji) has recently become a popular edible mushroom in Asia, and has been cultivated by culture methods such as bottle culture and bag-culture. It has been reported to exhibit many biological activities such as anti-tumor, 1,2) antioxidant, 1) and antiproliferative activity. 3) Several homologous polyisoprenepolyols named hypsiziprenols have recently been characterized in this mushroom. 4) Hypsiziprenols are the possible biosynthetic precursors of gymnopilins, bitter principles of H. marmoreus. 4) In the course of our studies on the bioactive principles of natural medicines and foodstuffs, 5,6) we evaluated the constituents of H. marmoreus for their antitubercular activity 7) as well as their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). 5,6) In this paper, we describe the antitubercular activity against Mycobacterium tuberculosis of seven sterols (1-7) and eight polyisoprenepolyols, hypsiziprenols (8-15), and inhibitory effects on the induction of EBV-EA by the TPA of seven sterols (1-7) and three hypsiziprenols (8, 10, 12) isolated from the non-saponifiable lipid (NSL) fraction of the extract of H. marmoreus.
MATERIALS AND METHODSExtraction, Isolation, and Identification Sliced fresh bodies of Hypsizigus marmoreus (11 kg), cultivated in Nagano Prefecture in 2001, were air-dried. The dried mushroom (833 g) was then extracted with hot CH 2 Cl 2 to give an extract (86 g). Alkaline hydrolysis (5% KOH in methanol (MeOH), reflux, 3 h) of the extract yielded a neutral nonsaponifiable lipid (NSL) fraction (9.0 g). Crystallization of the NSL fraction from MeOH yielded a precipitate (2.8 g), which was identified as ergosterol (1), 2) and a filtrate (4.9 g).The filtrate was subjected to column chromatography on silica gel (150 g) using an n-hexane-ethyl acetate (EtOAc) gradient of 1 : 0-1 : 1 as an eluent, which yielded fractions containing monohydroxy sterols (fraction A; Rf 0.83 on TLC developed with EtOAc-MeOH, 4 : 1), polyhydroxy sterols (fraction B; Rf 0.48), and polyisoprenepolyols (fraction C; Rf 0.24). Fractions A-C were purified by further chromatography on silica gel. Reversed-phase preparative HPLC (HPLC I; 25 cmϫ10 mm i.d., Pegasil ODS II (Senshu Scientific Co., Ltd., Tokyo, Japan) column; mobile phase: MeOH-H 2 O- Farmers' Federation; 787-1 Suzaka, Sazaka, Nagano 382-0084, Japan: and e College of Pharmacy, Nihon University; 7-7-1 Narashinodai, Funabashi, Chiba 274-8555, Japan. Received January 18, 2005; accepted February 28, 2005 Seven sterols (1-7) and eight polyisoprenepolyols (8-15), isolated from the non-saponifiable lipid fraction of the dichloromethane extract of an edible mushroom, Hypsizigus marmoreus (Buna-shimeji), were tested for their antitubercular activity against Mycobacterium tuberculosis strain H 37 Rv using the Microplate Alamar Blue Assay (MABA). Six sterols (2-7) and two polyisoprenepolyols (8, 12) showed a minimum inhibitory concentration (MIC) in the range of 1-51 m mg...