Isolation and growth optimisation of fresh water microalgae Asterarcys quadricellulare

The new strain of green microalgae Asterarcys quadricellulare (KT280061) was isolated from the different fresh water bodies in Chennai. The preliminary identification was done based on morphology and molecular identification of the isolate was carried out based on the partial 18S rRNA sequence analysis. The effects of physical parameters temperature, pH and light intensity were examined against the accumulation of Chlorophyll-a, chlorophyll-b, carotenoid, protein, carbohydrate and lipid content were studied. After the determination of physical parameters, the effect of the concentrations of KNO3, K2HPO4, MgSO4 and NaCl in the medium composition against the biochemical composition of A.quadricellulare were studied by varying one parameter at a time. The strain showed the maximum accumulation of chlorophyll-a (38.65 μg/ml), chlorophyll-b (20.76 μg/ml), carotenoid (14 μg/ml), protein (290 μg/ml), carbohydrate (545 μg/ml) and lipid (384 μg/ml) contents under the optimised conditions 40°C, pH 8.5, and light intensity 40 μmol m−2 s−1. The results showed both physical and chemical parameters were greatly influence the biochemical composition of microalgae strain KT280061.