The Potential of Capsicum annum Extracts to Prevent Lactococcosis in Tilapia

The capsaicin was extracted in-house from locally purchased chili pepper (Capsicum annum) using the conventional solvent extraction method. Varying concentrations of capsaicin were mixed with Lactococcus garvieae each and inoculated on Mueller Hinton agar to determine the minimum bactericidal concentration. Four groups of 100 fish each were injected with either 1) Capsaicin, 2) bacteria and capsaicin, 3) bacteria and 4) normal saline (negative control). The fish were observed for 7 days post treatment and experiment was repeated three times. Protection against infection was measured by the lack of clinical disease and survivability of the fish during period of experimentation. The minimum bactericidal concentration of capsaicin on growth of Lactococcus garvieae was 0.1967mg/ml. Significantly, more fish in the bacteria and capsaicin group survived (p<0.0001) compared to those injected with bacteria only. The findings suggest that chili pepper extract can prevent Lactococcus garvieae infection in tilapia.