台灣兩種真菌醱酵液及菌絲體之生物活性成分研究

Studies on the bioactive constituents of the fermented broths and mycelia of two fungus species isolated in Taiwan

曹雅菁(Ya-Ching Tsaur)

指導教授 ： 李宗徽 教授

臺北醫學大學/藥學院/生藥學研究所/碩士(2009年)

摘要

本研究利用抑制一氧化氮合成酶 (inducible nitric oxide synthase, iNOS) 來篩選34株單離自本土的真菌，藉以找尋出具有抗發炎活性的真菌株，發現其中13株真菌的醱酵培養液或菌絲體萃取物，對於離體RAW264.7細胞產生一氧化氮具有顯著的抑制作用。後續選定其中兩株包括：Psathyrella velutina (#96110901) 及Neosartorya sp. (#325) 進行其活性成分研究，再選擇以麥芽抽取物為培養基加以擴大培養後，針對醱酵液及菌絲所含代謝物進行一系列的分析、分離、純化與結構解析，計分離出10個化合物，分別為：psathyrone (1)、5-hydroxymethylfurfural (2)、bis-2,5-hydroxymethylfuran (3) 2-(4-hydroxy-2-octyl-5-oxotetrahydrofuran-3-yl)acrylic acid (6)、2-(4-hydroxy-2-octyl-5-oxotetrahydrofuran-3-yl)acrylic acid methyl ester (7)、maltol (8)、succinic acid (9) 和fumaric acid (10)，以及一混合物含 (22E,24S)-24-methylnorcholesta-5,7,22-trien-3β-ol (4) 和 (22E,24R)-24-methylnorcholesta-5,7,22-trien-3β-ol (5)(1：1)，其中psathyrone (1) 是過去未曾報導過的新化合物，化合物6和7則是首次由自然界中分離得到之天然物。天然物純質進一步進行抑制iNOS試驗，結果顯示化合物6和7對於離體RAW264.7細胞產生一氧化氮具有顯著的抑制作用，其半抑制濃度 (IC50) 分別為12.17 ± 1.49和11.36 ± 0.97 μM。

關鍵字

真菌 ； 誘導型一氧化氮合成酶Psathyrella velutina ； Neosartorya ； psathyrone

並列摘要

In this study, 34 strains of fungus isolated in Taiwan were cultured for the screening of iNOS (inducible nitric oxide synthase) inhibitory activities, and among them, the fermented broths or mycelia of 13 fungus species exhibited significant activities on the inhibition of NO production in lipopolysaccharides (LPS) activated mouse macrophage RAW264.7. Based on this findings, 2 strains of fungus including Psathyrella velutina (#96110901) and Neosartorya sp. (#325) were thus selected to investigate their bioactive constituents. A series of bioassay-guided chemical examination on the fermented broth or mycelia of these two strains were carried out, which resulted in the isolation of ten compounds. Their structures were elucidated to be psathyrone (1), 5-hydroxymethylfurfural (2), bis-2,5-hydroxymethylfuran (3), 2-(4-hydroxy-2-octyl-5-oxotetrahydrofuran-3-yl)acrylic acid (6), 2-(4-hydroxy-2-octyl-5-oxotetrahydrofuran-3-yl)acrylic acid methyl ester (7), maltol (8), succinic acid (9), fumaric acid (10), and a mixture of (22E,24S)-24-methylnorcholesta-5,7,22-trien-3β-ol (4), and (22E,24R)-24-methylnorcholesta-5,7,22-trien-3β-ol (5)(1：1) on the basis of spectroscopic analysis. Of these compounds identified, psathyrone (1) was a new compound with a rare 5/6/5/6-fused ring system, and 6 and 7 were isolated for the first time from natural resources. The bioactivities of all the pure entities were further evaluated. The results of biological tests indicated that 6 and 7 exhibited significant activities on the inhibition of NO production in lipopolysaccharides (LPS) activated macrophage RAW264.7 with IC50 values of 12.17 ± 1.49 and 11.36 ± 0.97 μM, respectively.

並列關鍵字

iNOS ； Psathyrella velutina ； Neosartorya ； psathyrone ； fungus

參考文獻

1. Moncada, S., Palmer, R.M.J., and Higgs, E.A. Nitric oxide: physiology, pathophysiology, and pharmacology. Pharmacol. Rev. 1991, 43, 109-42.

2. Nathan, C. Nitric oxide as a secretory product of mammalian cells. FASEB J. 1992, 6, 3051-64.

3. MacMicking, J., Xie, Q.W., and Nathan, C. Nitric oxide and macrophage function. Annu. Rev. Immunol. 1997, 15, 323-50.

4. Wink, D.A., and Mitchell, J.B. Chemical biology of nitric oxide: Insights into regulatory, cytotoxitic, and cytoprotective mechanisms of nitric oxide. Free Rad. Biol. Med. 1998, 25, 434-56.

5. Clancy, R.M., and Abramson, S.B. Nitric oxide: a novel mediator of inflammation. Proc. Soc. Exp. Biol. Med. 1995, 210, 93-101.