2. Materials and methods
2.1. Microalgae, growth medium and conditions
Spirulina platensis and Chlorella pyrenoidosa used in the present study were procured from the National Collection of Industrial Microorganisms (NCIM), National Chemical Laboratory (NCL), Pune-Maharashtra, India. The algae sample from a local pond was also collected from India gate, New Delhi, India. All the three samples were maintained in conical flasks containing 50 mL sterile BG11 media [25]. Proper shaking conditions were also maintained at 120 rpm and 24 °C for half an hour and then placed in the direct sunlight. Regular sub culturing was performed after every 15–18 days. In a growth chamber, the cultures were incubated under illumination (2000 lx) at 25 ± 1 °C with light:dark cycles of 12:12 h for 15 to 18 days with bubbling air at normal pressure required to maintain stirring of the cultures. With the concern for large scale cultivation of algae, growth was also attempted in tap water without BG 11 medium.