The incidence of life-threatening fungal infections has steadily increased in immunocompromised hosts such as HIV-infected persons and cancer and transplant patients.1 Invasive pulmonary aspergillosis and Pneumocystis carinii pneumonia are leading causes of death in bone marrow transplant recipients and in HIV-infected patients, respectively. Moreover, resistance to the azoles, which are the most widely used anti-fungal medicines today, is attracting much attention. Therefore, there is a continuing need for new antifungal agents to overcome these fungal diseases. Screening for new antifungal substances from fungal sources was carried out using pathogenic filamentous fungi, Aspergillus fumigatus FRESENIUS IFM41362 and A. niger VAN TIEGHEM IFM41398, and pathogenic yeasts, Candida albicans (ROBIN) BERKHOUT ATCC90028 and Cryptococcus neoformans (SANFELICE) VUILLEMIN ATCC90112. The MeOH extract of freshly isolated A. nishimurae IFM58441, cultivated on rice for 21 days at 25 °C, showed antifungal activities against the above four test organisms. The purification of this extract led to the isolation of a new yellow pigment, anishidiol (1) as the antifungal substance, along with 4-hydroxybenzaldehyde, 4-methylbenzylalcohol and monochaetin (2).2 The structure elucidation, antifungal activities and cytotoxic activities of 1 are described in this paper.

Polished rice (480 g) was soaked in water for 30 min and then sterilized with an autoclave. A. nishimurae IFM58441 was cultivated for 14 days in Roux flasks, each containing 140 g of moist rice. The cultivated rice was extracted with MeOH, and the extract was concentrated in vacuo. The residue was suspended in water and extracted with ethyl acetate. The EtOAc extract (3.6 g) was partitioned between n-hexane and MeCN to yield an MeCN-soluble mixture. The MeCN extract (3.0 g) was chromatographed using a Sephadex LH-20 column (GE Healthcare UK Ltd., Buckinghamshire, UK; 280 × 35 mm (initial condition), solvent system: n-hexane–CHCl3 (1:4) (180 ml), CHCl3–acetone (3:2) (220 ml), (1:4) (200 ml), acetone (200 ml) and MeOH (500 ml)) to yield 11 fractions. CHCl3–acetone (3:2) eluate was rechromatographed using MPLC with a silica gel (URTRA PACK SI-40B (300 × 26 mm, YAMAZEN Corp., Osaka, Japan), n-hexane–acetone (20:1) 450 ml, followed by acetone 150 ml elute; 1 fraction=15 ml) to give monochaetin (2: 9 mg) from fractions 19–20. Acetone eluate was rechromatographed using HPLC with a silica gel (Inertsil SIL 100A (250 × 10 mm, GL Sciences Inc., Tokyo, Japan), CHCl3–acetone (60:1)) to give the yellow compound, anishidiol (1: 3 mg). 4-Hydroxybenzaldehyde (4 mg) and 4-methylbenzylalcohol (16 mg) were obtained from MeOH eluate. The spectral data of 2 were identical to those from reports in the literature.2

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