The present work envisages close monitoring of variations in lipid profile and thereby analyzing the dietary status of the live feed Isochrysis galbana, a marine microalga by growing in 4 different standard culture media. Pure cultures of microalga were collected from the marine hatchery complex of the Central Marine Fisheries Research Institute, Kochi and cultured under four different media. Cultures were maintained in 4-litre haffkine flasks in triplicates under standard algal culture conditions. Fatty acid profiles were evaluated in microalgae cultured in all four algal culture media. Total saturated fatty acids ranged from 56.37% (Walne’s medium), 62.32% (Miquel’s medium), 75.02% (Chu#10 medium) to 79.35% (f/2 medium). Monounsaturated fatty acids were quantified as lowest of 12.21% in Miquel’s medium as against the highest of 32.76% in Walne’s medium. Polyunsaturated fatty acids (PUFAs) accounted for over 25.47% of the total fatty acids in Miquel’s medium whereas it was only 6.05% for f/2, 7.21% for Chu#10 and 10.87% for Walne’s media respectively. Statistical analysis of data brought to light that the composition of the fatty acid pattern of microalgae significantly (p≤0.05) varied with media of algal culture. By analyzing the results it can be confirmed that the nutritional value of Isochrysis galbana can be enhanced by culturing in Miquel’s medium.

Microalgae, Isochrysis galbana, fatty acid profiling, monounsaturated fatty acids, polyunsaturated fatty acids, live feed