Antibacterial Activity of the Sea hare, Dolabella auricularia, Egg String Extracts Against the Escherichia coli

An assay was conducted to determine the antibacterial activity of various concentrations of the Sea hare, Dolabella auricularia, egg string extracts against the bacterium, Escherichia coli, using disk diffusion method. The study was conducted at the Davao Oriental State College of Science and Technology (DOSCST), City of Mati, Davao Oriental. Escherichia coli showed susceptibility to the extract from a mixture of 0.6g powdered, dried-green, and dried-brown D. auricularia egg strings per ml ethanol.  Extract obtained from the freshly-laid green strings showed a mean of 8.51 mm zone of inhibition while the one from brown-dried egg strings had a mean of 7.71 mm. Results suggest that D. auricularia egg string extracts contain antibacterial factors which were evident if extracts are taken from dried egg strings and applied at a higher level of concentration of 0.6g/ml. The freshly-laid green egg strings showed to have more antibacterial factors than the mature, brown egg strings.