In vitro and In vivo Antibacterial Activity of Marine Alga Turbinaria ornata against Pseudomonas aeruginosa in the Freshwater Prawn Macrobrachium rosenbergii - Abstract
The in vitro and in vivo antibacterial activity of marine alga, Turbinaria ornata against Pseudomonas aeruginosa on Macrobrachium rosenbergii was studied. The hexanic, acetonic and methanolic extracts of T. ornata were subjected to in vitro study, which showed that the methanolic extract of T. ornata was worked well and produced 24.02 ± 0.47mm zone of inhibition against P. aeruginosa. In the in vivo study, the characteristic appearance of brown/black spots was detected all over the body of M. rosenbergii when the prawns were subjected to immersion in water containing P. aeruginosa (107 cells/mL) and fed with basal diet contained no incorporated T. ornata. Activities of metabolic enzymes (GOT and GPT) and antioxidant enzymes (SOD and catalase), and lipid peroxidation (LPO) were found to be significantly increased in the hepatopancreas of M. rosenbergii due to the infection with P. aeruginosa. These effects were greatly reduced/ neutralized when M. rosenbergii fed with methanolic extract of T. ornata incorporated feed, which in turn ultimately enhanced the survival rate of M. rosenbergii against P. aeruginosa infection. The 2D gel electrophoresis revealed degradation of hepatopancreatic proteins in P. aeruginosa infected M. rosenbergii, whereas the reverse was seen in methanolic extracts of T. ornata incorporated feed fed prawns. Thus, T. ornata possessed the potency of anti P.
aeruginosa. One of the active principles of T. ornata, 2-Hexadecen-1-ol, 3,7,11,15-tetramethyl-,[R-[R* ,R* -(E)]] was found to be bind with the protein, exotoxin-A of P. aeruginosa when molecular docking was performed. Therefore, there is scope for developing aquaculture medicine with T. ornata against Pseudomonas infection.