New naphthyl derivatives from Aspergillus californicus

Area of Science:

• Natural Product Chemistry
• Microbiology
• Pharmacology

Background:

• Aspergillus californicus is a fungal species known to produce bioactive secondary metabolites.
• Naphthyl-products represent a class of compounds with diverse biological activities.

Purpose of the Study:

• To isolate and characterize new naphthyl-products from Aspergillus californicus.
• To evaluate the antibacterial and cytotoxic activities of the isolated compounds.

Main Methods:

• Isolation of compounds using chromatographic techniques.
• Structure elucidation through extensive spectroscopic analyses (NMR, MS).
• Determination of absolute configuration using optical rotation and theoretical calculations.
• Antibacterial activity assessed by Minimum Inhibitory Concentration (MIC).
• Cytotoxicity evaluated using the HL-60 cell line (IC50).

Main Results:

• Two new naphthyl-products, calinaphthyltriol A (1) and calinaphthalenone A (2), were identified.
• The known compound ophiobolin X (3) was also isolated.
• Compounds 1 and 3 showed no significant antibacterial activity against tested bacterial strains (MIC > 96 µg·mL⁻¹).
• Compounds 1 and 3 displayed moderate cytotoxicity against the HL-60 cell line with IC50 values of 18 µg·mL⁻¹ and 24 µg·mL⁻¹, respectively.

Conclusions:

• The study successfully isolated and characterized novel naphthyl-products from Aspergillus californicus.
• Calinaphthyltriol A and ophiobolin X exhibit moderate cytotoxic effects on the HL-60 cell line.
• The isolated compounds do not possess significant antibacterial properties against the tested strains.