Concerning the requirements of effective drug candidates to combat against high rising multidrug resistant pathogens, we isolated three new linear lipopeptides, gageostatins A–C (
1–
3), consisting of hepta-peptides and new 3-β-hydroxy fatty acids from the fermentation broth of a marine-derived
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Concerning the requirements of effective drug candidates to combat against high rising multidrug resistant pathogens, we isolated three new linear lipopeptides, gageostatins A–C (
1–
3), consisting of hepta-peptides and new 3-β-hydroxy fatty acids from the fermentation broth of a marine-derived bacterium
Bacillus subtilis. Their structures were elucidated by analyzing a combination of extensive 1D, 2D NMR spectroscopic data and high resolution ESIMS data. Fatty acids, namely 3-β-hydroxy-11-methyltridecanoic and 3-β-hydroxy-9,11-dimethyltridecanoic acids were characterized in lipopeptides
1 and
2, respectively, whereas an unsaturated fatty acid (
E)-7,9-dimethylundec-2-enoic acid was assigned in
3. The 3
R configuration of the stereocenter of 3-β-hydroxy fatty acids in
1 and
2 was established by Mosher’s MTPA method. The absolute stereochemistry of amino acid residues in
1–
3 was ascertained by acid hydrolysis followed by Marfey’s derivatization studies. Gageostatins
1–
3 exhibited good antifungal activities with MICs values of 4–32 µg/mL when tested against pathogenic fungi (
R. solani,
B. cinerea and
C. acutatum) and moderate antibacterial activity against bacteria (
B. subtilis, S.
aeureus, S. typhi and P. aeruginosa)
with MICs values of 8–64 µg/mL. Futhermore, gageostatins
1–
3 displayed cytotoxicity against six human cancer cell lines with GI
50 values of 4.6–19.6 µg/mL. It is also noteworthy that mixed compounds
1+
2 displayed better antifungal and cytotoxic activities than individuals.
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