Chlorella sp. IM-01 has been isolated from wastewater sample collected from sewage treatment plant at Kabirkhedi, Indore (Madhya Pradesh). Strain was isolated and purified by repeated streaking on basal agar medium at pH 8.5 using standard isolation and culturing techniques on nitrogen supplemented BG-11 medium ( Kaushik, 1987). Composition of the medium (per liter) is: NaNO3 1.5 g, K2HPO4 0.04 g, MgSO4 0.075 g, CaCl2 0.036 g, citric acid 0.006 g, ferric ammonium citrate 0.006 g, EDTA 0.001 g, Na2CO3 0.02 g, and 1 mL trace metal mix (boric acid 2.86 g, manganese oxide 1.81 g, zinc sulphate 0.222 g, sodium molybdate 0.039 g, copper sulphate 0.079 g, and cobalt nitrate 0.049 g/L distilled water). The microalgal culture was maintained at a light intensity of 2000 lux using cool fluorescent tubes at 27 ± 3 °C in culture room.
Growth rate of this species is studied in BG-11 medium by measuring optical density at 660 nm (OD660) after every 24 h using UV–visible Spectrophotometer (Systronics Model 118). Initial OD is 0.01 and growth is monitored upto 25 days in triplicates.