EXPLORATION OF HAEMOLYTIC ACTIVITY AND ANTIBIOTIC SENSITIVITY OF BIOLUMINESCENT VIBRIO SPECIES FROM THOOTHUKUDI COAST

Bioluminescence, the phenomenon of light emission by living organisms, is widespread in the marine environment at all the trophic levels from bacteria to fish and is thought to play a crucial role in the general ecology of marine plants and animals. Bacterial bioluminescence is very sensitive to toxic materials and hence, several investigations have tested its application for determining the toxicity of several chemicals. Although bacterial bioluminescence has found applications in various fields, there are certain reports where they have been found to be toxic to marine fishes and shrimps. The bioluminescent Vibrio sp. is especially noted to be pathogenic to shrimps causing necrosis and luminosis. Hence, the present study was carried out to determine whether the bioluminescent bacteria belonging to Vibrio sp. from Thoothukudi coast can lyse mammalian RBCs by haemolysis test and carry out the antibiotic sensitivity test of the isolated species using six antibiotics. Three different bioluminescent bacteria were isolated and identified as Vibrio owensii, Vibro hyugaensis and Vibrio azureus. V. owensii and V. azureus were γ- haemolytic and V. hyugaensis was α-haemolytic which meant that none of them were able to haemolyse the blood completely. 5µg and 10µg of Amoxicillin, Cefotaxime, Ciprofloxacin, Ofloxacin, Roxithromycin, and Tetracycline were used to carry out the antibiotic sensitivity test. Vibrio owensii was most sensitive, Vibrio hyugaensis was resistant, and Vibrio azureus showed intermediate results for the antibiotics used in the experiment. All the bacteria were resistant to Roxithromycin.