Secondary metabolites and anti-inflammatory activity from the endophytic fungi Xylaria cubensis and Mollisia sp. in the Taiwan endemic plants

• Main Authors: Nai-Wen Fan, 范乃文
• Other Authors: Ih-Sheng Chen
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/60447185008493879197

碩士 === 高雄醫學大學 === 天然藥物研究所 === 100 === Xylaria cubensis and Mollisia sp. were two endophytic fungi found in the Taiwan endemic plants. The former was isolated from the leaves of Litsea akoensis Hayata var. akoensis (Lauraceae) and the latter was obtained from the root bark of Ardisia cornudentata Mez (Myrsinaceae). Xylaria cubensis was processed through liquid fermentation, while Mollisia sp. was cultured by solid‐state fermentation. The BuOH extract of Xylaria cubensis was partitioned with EtOAc and H2O. Chromatographic fractionation of the EtOAc layer led to the isolation of six new compounds: akonaphthalenol (1), akoenic acid (2), akolitserin (3), akotriol (4), akodionine (5), and xylaritriol (6), along with seven known compounds, including (R)-(－)-5-carbomethoxymellein (7), (R)-(－)-7-hydroxymellein (8), (S)-(＋)-piliformic acid (9), methyl indole-3-carboxylate (65), 4-(2''-hydroxyethyl)phenol (83), (R)-8-O-methylmellein (138), and (R)-5-methylmellein (139). Bioassay‐guided fractionation of the active EtOAc‐soluble layer of Mollisia sp. has led to the isolation of 15 compounds, including three new compounds：mollisinol A (10), mollisinol B (11), and mollisipyrrolal (13) and one first isolated from nature：mollisilactone (12), along with 11 known compounds ： palmitic acid (14), (R)-(－)-mevalolactone (15), chrysophanol (16), emodin (17), β-sitostenone (18), a mixture of β-sitosterol (19) and stigmasterol (20), ergosterol peroxide (21), 9,11- dehydroergosterol peroxide (22), 9-hydroxycerevisterol (23), and cerevisterol (191).The structures of these isolates were elucidated by spectroscopic evidences. So far, the isolates with enough amounts were screened for their ability to inhibit NO or IL‐6 production in LPS‐activated RAW 264.7 cells. Among these isolates, ergosterol peroxide (21) inhibited NO production in activated macrophages, and (R)‐ (－)‐7‐hydroxymellein(8) and emodin (17) showed IL-6 inhibitory activity, and the values of IC50 were 36.99, 9.41, and 5.97 μM, respectively.