Study the antimicrobial effect of three marine sponges (Dysidea sp.) collected at Persian Gulf on some pathogenic bacteria in planktonic and biofilm forms

Marine sponges have specific ability to growth in complex conditions deal with microorganisms by production of secondary metabolites. These metabolites can be used to degrade and inhibit the formation of microbial biofilms. Eliminating biofilms is important from the industrial and health aspect.
In this study the antimicrobial effects of methanol: dichloromethane (1:1) extracts of three marine sponges in Dysidea sp genus collected in 2015 at Persian Gulf, were studied against 6 human pathogenic bacteria. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of each extracts was determined. In biofilm level, the destruction of biofilm and inhibition of biofilm production by each extract was carried out separately.
The results of this study showed that the Dysidea spc have the highest inhibitory effect on planktonic form of studied bacteria. The maximum inhibitory effect on biofilm formation related to extracts of Dysidea sp.a in 12.5 mg/mL concentration against B. cereus and the minimum inhibitory effect in this concentration against P. aeroginosa. The highest destructive biofilm effect of Dysidea sp.c extract was observed in 6.25 mg/mL against K. pneumonia and lowest destruction in 12.5 mg/mL concentration was recorded against B. cereus.
The results obtained in this research confirmed that each marine sponges have different inhibitory effect against tested bacteria. This difference can be related to production of bioactive compounds and symbiosis microorganisms with these sponges.