The effect of leaves extracts of Clitoria ternatea Linn against the fish pathogens

Objective:To investigate the antimicrobial activity of Clitoria ternatea(C.ternatea) against the fish pathogens viz.,Pseudomonas aeruginosa(P.aeruginosa),Escherichia coli(E.coli),Klebsiella pneumonia(K.pneumonia),Bacillus subtilis(B.subtilis),Aeromonas formican(A.formicans)s, Aeromonas hydrophila(A.hydrophila) and Streptococcus agalactiae(S.agalactiae )isolated from diseased Tilapia(Oreochromis niloticus).Methods:The extracts of C.ternatea was tested against P.aeruginosa,E.coli,K.pneumonia,B.subtilis,A.formicans,A.hydrophila and S.agalactiae by the agar well diffusion method.Results:Different extracts of C.ternatea showed inhibitory effects against P.aeruginosa,E.coli,K.pneumonia,B.subtilis,A.formicans,A.hydrophila and S. agalactiae.Ethyl acetate extracts of C.ternatea showed maximum of zone of inhibition against A. formicans(18 mm),A.hydrophilia(19 mm),B.subtilis(19 mm) and P.aeruginosa(21 mm) next to that ethanol extract of C.ternatea showed A.formicans(18 mm) and E.coli(14 mm) followed by Acetone extract showed maximum zone of inhibition S.agalactiae(19 mm) and K.pneumonia(17 mm).Conclusions:The antimicrobial activities of all the four plant extracts are comparable and their potential as alternative in the treatment of infectious by these microorganisms was present in the fish.Susceptibility testing is conducted on isolates using drugs selected on the basis of their importance to human medicine and use in fish production.