Abstract

The ethyl acetate extract of the new terrestrial Streptomyces sp. isolate TN272 delivered eighteen bioactive compounds, including four homologues cyclic lipopeptides. Structures of the first fourteen compounds (1 to 14) were established on the basis of different spectroscopic techniques, including GC-MS, ESI-MS, HRESI/EIMS, 1D NMR experiments, and by comparison with related compounds. They are: 2,4-bis (1,1-dimethylethyl) phenol (1) 1-hexadecene (2), 5-octadecen (3), cis-cyclo (L-prolyl-L-valyl) (4), hexadecanoic acid (5), cyclo (leucyl-prolyl) (6), cis-cyclo(phenyl- prolyl) (7), 3(Z)-tetradecene (8), trans-1,10-dimethyl-trans-9-decal (9) and 1-nonadecene (10) together with a mixture of four hydroxy fatty acids; 7-hydroxy-tetradecanoic acid (11), 7-hydroxy-pentadecanoic acid (12), 9-hydroxy-hexadecanoic acid (13) and 9-hydroxy-heptadecanoic acid (14). The UV non absorbing three known cyclic lipopeptides homologues (15₁ to 15₅, 16₁ to 16₄, 17₁ to 17₂) and unknown cyclic lipopeptides (18) (m/z 662) were detected during hyphenated HPLC-UV/Vis-ESI MS screening. According to our biological studies, these unknown cyclic lipopeptides possess antifungal activities against the two tested fungi, Fusarium sp. andCandida tropicalis R2 CIP203.

Key words: New Streptomyces sp.TN272, identification, bioactive compounds, purification, structure elucidation, unknown cyclic lipopeptides, antifungal activity.