P-Sulfooxyphenylpyruvic acid derivatives from the green macroalga Caulerpa taxifolia

The green macroalga Caulerpa taxifolia has been of a great research interest since its accidental introduction in the Mediterranean sea in 1984. This specie has yielded several structurally diverse and biologically active compounds such as caulerpenyne (Fig. 1) [1]. This metabolite, constituted by a diacetoxybutadiene moiety, exhibited very potent antibacterial properties [2]. Within our ongoing research projects devoted to the isolation of new bioactive metabolites from Mediterranean marine organisms, a specimen of the freshly collected green algae Caulerpa taxifolia, was investigated. The crude polar organic extract was subjected to a series of chromatographic separations that has led to the isolation of new metabolites (1a and 1b) structurally close to the already reported ones (2a and 2b) (Fig. 2) [3].

The structures of the isolated compounds were determined on the basis of extensive analyses of their spectroscopic data (NMR, MS, and UV). All the derivatives exhibited potent antibacterial activity against E. coli, and antifungal activity against C. albicans and A. brasiliensis with MIC < 5 ppm.

Fig. 1: Caulerpenyne from Caulerpa taxifolia.

Fig. 2: New p-sulfooxyphenylpyruvic acid methyl ester (1a and 1b) from Caulerpa taxifolia.

Acknowledgements: E. Sfecci is the recipient of a thesis grant from the "Conseil Régional Provence Alpes Côte d'azur" and a travel grant from the “Association Lapervenchelif”. M. Mehiri research is supported by the french program ENVI-Med "MEDIBIO", the ANR/Investissements d'Avenir program via the OCEANOMICs project (grant #ANR-11-BTBR-0008), and the H2020 European program via the EMBRIC project.

Keyword: Caulerpa taxifolia.

References:

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