LAUSR

During a program of investigation on potentially bioactive secondary metabolites from Formosan endemic plant endophytes, an endophytic fungal strain, Mycoleptodiscus sp. (Magnaporthaceae) BCRC 09F0149, was isolated from the root of Piper sintenense Hatus. (Piperaceae). Previous chemical investigations of the genus Mycoleptodiscus have received less attention, and only a few articles have been reported [1–3]. In the course of our search for potentially diverse secondary metabolites from natural fungal sources, we have investigated the minor metabolites of the genus Mycoleptodiscus and examined the EtOAc-soluble fraction of Mycoleptodiscus sp. Current phytochemical investigation of the above-mentioned fungus has led to the isolation of seven metabolites, including two known aliphatics, one benzenoid, and four known steroids. The structures of the isolated metabolites were determined by extensive analysis of their spectroscopic data as well as by comparison with literature reports. The chemistry and bioactivity of Mycoleptodiscus sp. 09F0149 have never been studied previously. Among them, compounds 1–7 were isolated for the first time from the genus Mycoleptodiscus. The structures of compounds 1–7 were established by comparisons of their 1H NMR and ESI-MS or EI-MS data with literature data: cis-11-eicosenoic (1) [4], 2,3-dihydroxypropyl hexadecanoate (2) [5], benzoic acid (3) [6], -sitosterol (4) [7], ergosterol (5) [8], a mixture of ergosterol peroxides (6) [9] and 5 ,8 -epi-dioxy-24(R)-ergosta-6,22-dien-3 olergone (7) [10]. General Experimental Procedures. TLC: silica gel 60 F254 precoated plates (Merck). Column chromatography (CC): silica gel 60 (70–230 or 230–400 mesh, Merck) and Spherical C18 100A Reversed Phase Silica Gel (RP-18) (particle size: 20–40 m) (Silicycle). UV Spectra: Jasco UV-240 spectrophotometer; max (log ) in nm. Optical rotation: Jasco DIP-370 polarimeter; in CHCl3. IR Spectra: Perkin-Elmer-2000 FT-IR spectrophotometer; in cm –1. 1H, 13C, and 2D NMR spectra: Varian-VNMRS-600 and Varian-Mercury-400 spectrometers; in ppm rel. to Me4Si, J in Hz. EI-MS: VG-Biotech Quatro5022 mass spectrometer; m/z (rel. %). HR-EI-MS spectra were recorded on a Finnigan/Thermo Quest NAT mass spectrometer. ESIand HR-ESI-MS: Bruker APEX-II mass spectrometer; in m/z. Microorganism, Cultivation, and Preparation of the Fungal Strain. The fungus used in this study was isolated from the root of Piper sintenense Hatus. (Piperaceae) and identified as Mycoleptodiscus sp. 09F0149 on the basis of the rDNA internal transcribed spacer (ITS) gene sequence. The fungal strain was identified as Mycoleptodiscus sp. (family Magnaporthaceae) by Dr. Sung-Yuan Hsieh based on cultural and anamorphic data. The identification was further confirmed by sequence analysis of the rDNA-ITS (internal transcribed spacer) region. A nucleotide-to-nucleotide BLAST (nucleotide sequence comparison program) query of the NCBI database yielded Mycoleptodiscus sp. with accession No. FJ478407.1 as the closest match to the ITS rDNA of 09F0149 (98%). The strain is preserved with the Bioresource Collection and Research Center (BCRC) of the Food Industry Research and Development Institute (FIRDI) under the ID No. 09F0149. 7-Day-old