EVALUATION OF IMMUNOSTIMULANT POTENTIAL OF SOLANUM NIGRUM L. USING FISH, ETROPLUS SURATENSIS CHALLENGED WITH APHANOMYCES INVADENS

Abstract

In the present investigation found immunostimulant potential plants being an alternative for preventing fish diseases. Six groups of experimental fishes (E. suratensis) were immunized with 0.2ml (4ppm) of five different extracts of Solanum nigrum through intra-peritoneal injection and challenged with heat killed Aphanomyces invadans. Blood collected from immunized and normal fish were analyzed such as, radial immunodiffusion, antibody titration, Nitro Blue Trtrazolium Assay, determination of IgG concentration and host Resistance Test. In both control and the experimental groups the peak antibody response was on day 21 after immunization and decreased towards 28th day. The Methanol extract treated group, the antibody response was significantly enhanced on the day 14 and day 21 (p<0.05). The highest IgG level was on day 21 and decreased towards day 28. In Chloroform extract treated group the neutrophil activity was significantly enhanced on day 6 (p<0.05). In Toluene extract treated group the neutrophil activity was significantly enhanced on day 6 (p<0.05). The ethanol and methanol extract treated group showed less mortality rate when compared to chloroform toluene and water extract treated group. From the results it can be concluded that plant extracts have great potential as immunostimulant against microorganisms and that they can be used in the treatment of infectious diseases caused by microorganisms.