A preliminary investigation on the effects of the echinoderm Archaster typicus extract on caudal fin regeneration and heart rate of zebrafish, Danio rerio

This study investigated the effect of the different concentrations of the crude hexanoic extract of the echinoderm, Archaster typicus, on the inherent ability of the zebrafish, Danio rerio, to regenerate its caudal fin after amputation, as well as on its heart function. The 100-ppm extract concentration showed the longest regenerated fin of 0.147 mm at 24h, 0.234 mm at 48h, and 0.598 mm at 72h. The fastest regeneration rate was at 100 ppm from 24 to 72. At 72h, the average length of fin regeneration in the negative control, 0.0 ppm (water only), and the concentrations 25 and 50 ppm were highly equivalent at 0.41 mm. The regenerated fin was longest in 100 ppm (0.6 mm) and shortest in 200 ppm (0.35 mm). After exposure to the positive control, benzaldehyde, for 72 h, the length of the regenerated fin was 0.66 mm at 25 ppm and 0.88 mm at 200 ppm. Increasing the benzaldehyde extract concentration also increased the regeneration length, with a maximum of 0.88 mm at 200 ppm. ANOVA showed significant differences in the length of the new fin among replicates, concentrations, and exposure durations. The effect of the echinoderm extract was a decrease in heart rate with increasing extract concentration and exposure duration (bradycardia).