Application Of Methanol Extract Of Bangkal Leaves (<i>Nauclea Subdita</i> (Korth) Steud.) As A Therapeutic Herb For Pearl Catfish (Clarias <i>Gariepinus</i>) Infected With <i>Aeromonas Hydrophila</i> Bacteria

Abstract Pearl catfish ( Clarias gariepinus ) is one type of catfish that is widely cultivated as a consumption fish. One of the diseases that often attacks is Motile Aeromonas Septicemia (MAS) which is caused by the bacterium Aeromonas hydrophila . The use of herbal bladder leaf therapy can be done by the soaking method. This study aims to find out the most effective extraction method and solvent to inhibit the growth of A. hydrophila and the effect of methanol extract of bangkal leaves on the survival of pearl catfish. This study used a complete Random Design (RAL) with 5 treatments and 3 replicates, namely A (soaking of methanol extract of bangkal leaves at a dose of 50 mg/L), B (soaking of methanol extract of bangkal leaves at a dose of 100 mg/L), C (soaking of methanol extract of bangkal leaves at a dose of 150 mg/L), K- (no treatment) and K+ (bacterial infection without soaking). The parameters observed were, Antibacterial activity, survival and water quality. The results showed that the dry method of methanol solvent had the highest inhibition of 5.3 mm, the treatment of pearl catfish using methanol extract of bangkal leaves was able to increase the survival of pearl catfish by up to 100%. The water quality parameters during the study were still tolerable by the fish, namely a temperature of 27.3 - 27.4°C, a pH of 5.57 - 5.98 and a DO of 1.4 – 1.9.