Performance of Zeolite-PEI antibacterial filter in breeding tanks of Giant freshwater prawn Macrobrachium rosenbergii

Use of effective substances to inhibit bacteria in the aquatic environment due to indiscriminate and long-term use of antibacterial substances such as antibiotics seems to be necessary. Polyethyleneimine (PEI) is a synthetic polymer with antibacterial properties and chemical formula (C2H5N)n which consists of many side groups of NH2, the use of this polymer due to its antibacterial property in binding with different substrates can be considered. Among these substrates that are widely used in aquaculture is Zeolite. In this study, zeolite was coated with PEI polymer with two concentrations of 1 and 2 mg/l and after confirmation by Fourier transform infrared spectroscopy (FTIR) analysis is placed inside the filters. The function of the filters was determined by measuring the bacterial load of the water, survival and growth of post larvae. The results showed that negative control, treatment of zeolite modified with concentration I, treatment of zeolite modified with concentration II of PEI polymer, treatment of natural zeolite and positive control at 104 CFU/ml Aeromonas hydrophila bacteria on the 10 days of the experiment were grew 50, 125, 125, 348 and 380 colony/100 ml in TSI medium, which shows a decrease of 67.1% of the bacterial load in both modified treatments with concentrations I and II of PEI polymer compared to the positive control. Also, the survival rate of postlarvae showed a significant increase in the treatment of modified zeolite with concentration I and II compared to the negative control (P<0.05). However, there was no significant difference between treatments in dry weight and length (P>0.05). Finally, after summarizing and comparing the results of this study with others, it can be concluded that the use of zeolite modified with PEI polymer in the filtration system of giant freshwater prawn Macrobrachium rosenbergii post larval rearing tanks has a potential effect on bacterial reduction of Aeromonas hydrophila bacteria.