Antineoplastic unsaturated fatty acids from Fijian macroalgae

Area of Science:

• Marine Natural Products Chemistry
• Algal Phytochemistry
• Pharmacognosy

Background:

• Marine algae are a rich source of diverse bioactive compounds.
• Fijian marine flora, including Tydemania expeditionis and Hydrolithon reinboldii, are underexplored for novel metabolites.
• Fatty acids and glycolipids often exhibit significant biological activities.

Purpose of the Study:

• To isolate and characterize novel and known compounds from Fijian marine algae.
• To evaluate the cytotoxic activity of isolated compounds against a panel of human tumor cell lines.

Main Methods:

• Phytochemical analysis of algal extracts.
• Structure elucidation using 1D and 2D NMR spectroscopy and ESI-MS.
• In vitro cytotoxic assays against breast, colon, lung, prostate, and ovarian cancer cell lines.

Main Results:

• Isolation of two new unsaturated fatty acids: 3(zeta)-hydroxy-octadeca-4(E),6(Z),15(Z)-trienoic acid (1) and 3(zeta)-hydroxy-hexadeca-4(E),6(Z)-dienoic acid (2).
• Identification of a new glycolipid, lithonoside (3), and several known compounds.
• Compounds 1, 2, and 4 exhibited moderate inhibitory activity against tumor cell lines (IC50 values: 1.3–14.4 µM).

Conclusions:

• The study successfully isolated and characterized novel compounds from Fijian algae.
• Compounds with conjugated double bonds show potential as anticancer agents.
• Further research is warranted to elucidate the mechanism of action for these cytotoxic fatty acids.