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)

Abstract

Introduction: 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).
Materials & Methods: Based on the obtained results, the methanolic extract stopped the
growth of Vibrio harvey bacteria at 450 ppm.
Results: 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).
Conclusion: 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.