The project tested whether freshwater sponge extracts had antimicrobial properties, which affect the growth of nosocomial bacteria. Furthermore, it investigated if antimicrobial properties of the extracts originated from sponges or their microbiome. Two freshwater sponge species Spongilla lacustris and Ephydatia fluviatilis were tested for antimicrobial properties. Sponges of each species were collected from rivers (full microbiome) and laboratory grown in sterile water (reduced microbiome). Sponge samples were dried and extracted in methanol. After evaporation of methanol extracts were resuspended in DMSO. Antimicrobial properties were assessed by disc diffusion and recording the minimal inhibitory zone (MIZ) for the bacteria Acinetobacter baumanniii, Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus and Staphylococcus epidermidis.None of the tested sponge extracts suppressed the growth of P. aeruginosa, S. aureus or S. epidermidis. Only K. pneumoniae was inhibited by all extracts, with the extracts from laboratory grown sponges resulting in significantly wider MIZs (U=73-89, p=0.004-0.019). A. baumanniii, E. coli and E. faecalis were only inhibited by the extract from riverine S. lacustris. Freshwater sponges are potential sources of antimicrobial compounds, particularly against K. pneumoniae. The antimicrobial properties of laboratory grown sponges suggested that the bioactive molecules which inhibited K. pneumoniae originated from the sponge. However, the enhanced antimicrobial properties of S. lacustris from rivers indicated that there was also a contribution by the microbiome to these extracts’ inhibitory efficacy. Successful clinical therapies against nosocomial bacteria with multidrug resistance will increasingly require new antimicrobial compounds. This study has provided evidence that freshwater sponges contain bioactive molecules. The latter do inhibit bacterial growth and therefore could be a source of antimicrobial compounds, which may originate both from the sponges and their microbiome.
|Title of host publication||Unknown Host Publication|
|Publisher||Society for Applied Microbiology|
|Number of pages||2|
|Publication status||Accepted/In press - 14 Mar 2018|
|Event||SfAM 7th ECS research symposium - Birmingham|
Duration: 14 Mar 2018 → …
|Conference||SfAM 7th ECS research symposium|
|Period||14/03/18 → …|
Bibliographical noteReference text: Marinho, PR, Muricy, GRS, Silva, MFL, Marval, MGDL, Lamport, MS (2010). Antibiotic-resistant bacteria inhibited by extracts and fractions from Brazilian marine sponges. Revista Brasileira de Farmacognosia, 20, 267-275.
Pejin, B, Talevska, A, Ciric, A, Glamoclija, J, Nikolic, M, Talevski, T (2014). Anti-quorum sensing activity of selected sponge extracts: a case study of Pseudomonas aeruginosa. Natural Product Research, 28(24), 2330–3.
- freshwater sponges
- antibiotic resistance
- antimicrobial resistance