Vol. 2, Issue 5 (2017)
Biomass production and biochemical variability of marine microalgae Isochrysis galbana in relation to light intensity
Author(s): Dr. Neha Mishra
Abstract: Isochrysis galbana is a marine microalga that has a great potential as a source of animal feed, human nutrition and biofuel. Light intensity is one of the key limiting factors for the growth of dense culture of photosynthetic microalgae both in indoor and outdoor culture. In this study, we investigated the effect of different light intensity (35, 125 and 275 μmol photons m−2 s−1) on the biomass production and its biochemical composition (protein carbohydrate, lipid and pigments). Growth is calculated daily by measuring optical density at 710nm and dry weight of filtered cells was incinerated at 550ºC in a muffle oven. The biochemical components protein, lipid, carbohydrate and pigment were measured by Lowry, Bligh and Dryer, Dubois and Strickland and Parsons Method respectively. In this study, reported culture (LL) grown under low light have maximum amount of protein content (44.73+0.50%DCW) and chlorophyll a (4.67+0.28mg/L) whereas culture (HL) grown under high light intensity were highest in the lipids contents (30.66 ± 0.30 % of DCW) and carbohydrates (16.06 ± 0.70% of DCW). Maximum accumulation of total carotenoids (4.89 ± 0.25 mg/L) reported in culture (HL) grown under high light and with decreased light carotenoids decreases. In conclusion result reported that varied light intensity have a significant impact on growth, dry weight and biochemical composition of Isochrysis galbana which have wide application in aquaculture, nutraceutical, pharmaceutical and biofuel industry.