Antimicrobial and Antioxidant Activities of Novel Marine Bacteria (Bacillus 2011SOCCUF3) Isolated from Marine Sponge (Spongia officinalis)

Bacillus species represent a rich source of new bioactive metabolites that can combat diseases.

Bacillus strain was isolated from the marine sponge Spongia officinalis and routinely maintained on marine broth. The bacteria strain was identified as Bacillus 2011SOCCUF3 using 16S rDNA sequencing. The strain was cultured on Tryptone Casein Oat Soluble Starch (TCOATSS) media with continuous agitation for 4 days. The fermented broth was centrifuged, and the supernatant was mixed with 10% (w/v) of adsorbent resin (XAD-7HP and XAD-16N, 1:1) and shaken continuously at a reduced speed for 7 h; and the resin was collected by filtration through sintered glass funnel and washed with MilliQ water, and then eluted with methanol to obtain the extract. The extract was evaporated in vacuo at reduced temperature and pressure to obtain the dry extract. The dry extract was purified by vacuum liquid chromatography, eluting with methanol in acetone gradient. The in vitro antimicrobial and antioxidant activities were investigated using the agar-well diffusion, DPPH scavenging and the phosphomolybdate methods respectively.

The extract and fractions showed good antimicrobial activities with minimum inhibitory concentration range of <1.0 mg/mL. The extract and fractions also exhibited good antioxidant activities with their IC50 values been comparable to the standard.

Thus, a novel Bacillus strain isolated from the marine sponge (Spongia officinalis) obtained from Cortiou and Riou, France, exhibited promising antimicrobial and antioxidant activities.