New Natural Product from Botryosphaeria australis, an Endophyte from Mangrove Avicennia marina

Abstract

Chemical investigation of the endophytic fungus Botryosphaeria australis isolated from Avicennia marina originally from Hainan Province, P.R. China, yielded a new compound botryosphaenin (1), from the class of napthoquinone, together with 5 known compounds, botryosterpene (2) and 5-hydroxy-2,7-dimethoxynaphthalene-1,4-dione (3) and its derivatives, 6-ethyl-5-hydroxy-2,7-dimethoxynaphthalene-1,4-dione (4), O-methylaspmenone (5), Omethylasparvenone (6) and 5-(carboxymethyl)-7-hydroxy-1,4a-dimethyl-6-methylene decahydron aphthalene-1-carboxylic acid (7). Their structures were determined on the basis of spectroscopic methods including 1D ( 1 H, 13 C, and DEPT) and 2D (COSY, HMQC, HMBC, and ROESY) NMR experiments and by mass spectroscopic measurements The new compounds, 1 showed activity against the bacterial pathogens Staphylococcus aureus, several Streptococcus species and Bacillus subtilis, but also against the eukaryotic cell lines THP-1 (human leukemia monocyte) and BALB/3T3 (mouse embryonic fibroblast). Keywords: Mangrove, Avicennia marina, Botryosphaeria australis, antibiotic activities, cytotoxicity ABSTRAK Telah dilakukan penelitian kimiawi tentang jamur endofit Botryosphaeria australis yang diisolasi dari bakau Avicennia marina yang tumbuh di kawasan Provinsi Hainan, Republik Rakyat China. Dari penelitian ini diperoleh senyawa botryosphaenin (1), yang merupakan senyawa baru , dari kelas napthoquinone , bersama dengan lima senyawa yang diketahui sebelumnya yaitu, botryosterpene (2) dan 5 -hidroksi -2,7 -dimetoksinaftalen -1 ,4 -dion (3) dan turunannya , 6 -etil -5 -hidroksi -2 ,7 -dimetoksinaftalen -1 ,4 -dion (4) , O -metilaspmenon (5) , O -metilasparvenon (6) dan 5 -( karboksimetil ) -7 -hidroksi -1 , asam 4a -dimetil -6 -1 -metilendekahidronaftalen karboksilat (7). Strukturnya kimia dari senyawa-senyawa tersebut di atas ditentukan berdasarkan analisis spektroskopi Resonansi Magnetik Inti (NMR) termasuk 1D (1H , 13C, dan DEPT) dan 2D ( COSY, HMQC, HMBC, and ROESY) serta menggunakan spektroskopi massa. Senyawa baru yang diisolasi (1) tidak hanya menunjukkan aktivitas yang kuat melawan bakteri patogen Staphylococcus aureus, beberapa spesies Streptococcus dan Bacillus subtilis, tetapi juga terhadap galur sel eukariotik THP -1 (human leukemia monocyte) dan BALB/3T3 (mouse embryonic fibroblast) .

Secondary Metabolites Produced by Neofusicoccum Species Associated with Plants: A Review

“…In fact, the phytotoxic activity of some of them has been investigated on leaves, leaf discs or detached leaves of grapevines showing concentration dependent necrosis. As reported by Abou-Mansour et al [21], (R)-(−)-3-hydroxymellein (25) is the most active mellein tested with 62% leaf disc necrosis. Among cyclohexenones, the compounds with an epoxydic ring are the most active (i.e., cyclobotryoxide (1), (−)-terremutin (2), (+)-epi-sphaeropsidone (6)), while (+)-(6R,7S)-dia-asperlin (8) is responsible for 33% of leaf disc necrosis.…”

“…The most significant structural differences are the presence of hydroxyl, methoxyl, alkyl or acetate groups in different positions on the 1,4-naphthalenoid ring, but these compounds share the hydroxy group at C-5 and the methoxy groups at C-2 and C-7. These groups are all present in the 5-hydroxy-2,7-dimethoxynaphthalene-1,4-dione (50) [25], which was identified as a product of an endophytic strain of B. australis (=N. australe) isolated from the mangrove plant Avicennia marina, together with botryosphaenin (45), a new naphtoquinone.…”

“…australe) isolated from the mangrove plant Avicennia marina, together with botryosphaenin (45), a new naphtoquinone. This latter compound and its 6-ethyl analogue (6-ethyl-5-hydroxy-2,7-dimethoxynaphthalene-1,4-dione 47) showed antibiotic and antiproliferative activities with a minimum inhibitory concentration (MIC) ranging from 2 to 32 μg mL −1 when tested on Gram-positive bacteria and an IC50 value from 0.5 to 2 μg mL −1 when tested on different cell lines [25].…”