Introduction:

For millions of years, organisms that inhabit the marine environment have been developing strategies to adapt to environmental changes and with this, synthesizing a great variety of secondary metabolites with biological activities.

Objective:

Evaluate the antimicrobial and antioxidant activities and identify the fatty acids of the methanolic extract of the marine sponge Tetilla rodriguesi collected in Cispatá bay, Colombian Caribbean.

Methods:

T. rodriguesi specimens were subjected to extraction to obtain the methanolic extract, of which the fatty acids were obtained, esterified and identified it using chromatographic techniques. With the methanolic extract, the antioxidant activity was carried out against the radicals ABTS+• and DPPH•, and the antimicrobial activity by the microdilution method against reference strains of Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Enterococcus faecalis and Candida albicans; in addition to clinical isolates of Candida albicans (obtained in blood) and Candida krusei (obtained in catheter).

Result:

The results yielded the identification of 19 fatty acids of different nature. In the analysis of the antioxidant activity could be found that inhibition of radical evaluated was moderate (296.98 ppm for ABTS+• and 3 523.62 ppm for DPPH•). The evaluation of antimicrobial activity showed that the methanol extract of T. rodriguesi managed to greatly reduce the growth of all microorganisms tested.

Conclusions:

Despite the fact that porifers tend to have large fatty acids, in this study the presence of fatty acids with a carbon chain greater than 20 members was not found. The result of antioxidant activity is largely resembled that found in other species of the same phylum. In this research, it was established that the methanolic extract of T. rodriguesi managed to greatly reduce the growth of all the bacterial and fungal strains used.