The inhibitory effect of methanolic, acetone, and aqueous extracts of razor clam (Solen vagina) on the growth of Vibrio harveyi bacteria in post-larvae of Vannamei shrimp (Litopenaeus vannamei)

This study was aimed to compare the halo diameter (mm) caused by the lack of bacteria growth (Vibrio harvey) in the post-larvae of Vannamei shrimp (Litopenaeus vannamei) under the influence of methanolic, acetone, and aqueous extracts (ppm) of razor clam (Solen vagina). Based on the obtained results, the methanolic extract stopped the growth of Vibrio harvey bacteria at 450 ppm. Although the use of this extract stopped the growth of bacteria at a concentration of 450 ppm, the diameter of the created halo was smaller compared to the halo of non-growth caused by antibiotics. Acetone extract prevented the growth of Vibrio harvey bacteria at 250 ppm and higher concentrations and created a lack of growth halo with a diameter of 2.8 cm. Also, the aqueous extract did not have any inhibitory effect. The results of the mean comparison test showed that there was a significant difference between different concentrations of methanolic and acetone extracts (P<0/05). Also, significant differences were observed between the same effective concentrations of different treatments (250, 300, 350, 400 and 450 ppm) (P<0/05). Therefore, methanolic and acetone extracts of S. vagina can be used as a bioactive substance to prevent vibriosis in Litopenaeus vannamei. However, more studies are suggested to investigate other extracts of this species and their effects.