Aromatic polyketides from marine algicolous fungi

Area of Science:

• Marine natural products chemistry
• Fungal secondary metabolism
• Marine microbiology

Background:

• Marine-derived fungi are a rich source of novel bioactive compounds.
• Endophytic fungi, living within algae, represent an underexplored niche for natural product discovery.
• Dihydroisocoumarins are a class of compounds with diverse biological activities.

Purpose of the Study:

• To isolate and characterize new natural products from marine-derived fungi.
• To investigate the chemical diversity of fungal endophytes associated with marine algae.
• To elucidate the structures of novel compounds using spectroscopic methods.

Main Methods:

• Isolation of fungal strains from marine algae.
• Cultivation of fungal endophytes under controlled laboratory conditions.
• Structure elucidation of isolated compounds using extensive spectroscopic measurements (NMR, MS).

Main Results:

• Two new natural products, acremonisol A (1) and (3 R)-7-hydroxy-5-methylmellein (2), were isolated.
• Both compounds were identified as aromatic pentaketides belonging to the dihydroisocoumarin class.
• The fungi Acremonium sp. and Nodulisporium sp., endophytes of marine algae, were the source of these compounds.

Conclusions:

• The marine-derived fungi Acremonium sp. and Nodulisporium sp. produce novel dihydroisocoumarins.
• Acremonisol A and (3 R)-7-hydroxy-5-methylmellein represent new additions to the known natural products.
• This study highlights the potential of marine algal endophytes as a source of structurally diverse secondary metabolites.