Antibacterial activity of sea cucumber (Holothuria leucospilota) extracts on Lactococcus garvieae and Aeromonas hydrophila

In the present study investigated the antibacterial activity of the methanol and n-hexane extracts of the sea cucumber Holothuria leucospilota on Lactococcus garvieae and Aeromonas hydrophila. The antibacterial activity was determined using a serial dilution method with concentration 7.81, 15.62, 31.25, 62.5, 125, 250, and 500 mg/mL methanol and n-hexane extract of gonads and muscle tissue of sea cucumber. Then bacterial samples were added to dilutions, and optical density was recorded at 0 (before bacterial inoculation) after bacterial inoculation, 12 and 24 hours after inoculation. Minimum Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC) of the extracts were determined by the pour plate method. The results showed that the n-hexane hexane extract from gonads and muscle tissue of sea cucumber did not affect MIC and MBC of the mentioned bacteria. Meanwhile, methanol extract from gonads and muscle tissue of sea cucumber had antibacterial activity against Lactococcus garvieae and Aeromonas hydrophila.