Paradendryphiella arenariae an endophytic fungus of Centella asiatica inhibits the bacterial pathogens of fish and shellfish

Agar plug diffusion and agar well diffusion assays revealed that endophytic fungus CAS1 exhibits maximum antagonistic activity against bacterial fish pathogens. The ethyl acetate crude extract of CAS1 exhibited the maximum zone of inhibitions against <i>Aeromonas hydrophila</i> (21 ± 0.11 mm), <i>Aeromonas caviae</i> (18 ± 0.1 mm), <i>Edwardsiella tarda</i> (23 ± 0.11 mm), Vibrio anguillarum (19 ± 0.05 mm) and <i>Vibrio harveyi</i> (20 ± 0.27 mm). The MIC and MBC values extract varied reliant on the trial pathogens ranging between 12.5-100 μg/mL and 25-100μg/mL correspondingly. The morphological and molecular characterization of potential isolate CAS1 was confirmed as <i>Paradendryphiella arenariae</i> by 18S rRNA ITS gene sequencing with 99.18% identity. This is the foremost findings to study the antagonistic effect of <i>Paradendryphiella arenariae</i> isolated from the stem of <i>Centella asiatica</i> against bacterial fish pathogens which can be used as natural effective antibacterial agents in aquaculture.