Green Synthesis and Characterization of CaO Nanoparticles using Hen Eggshells and its Impact on Biomass Concentration, Chlorophyll-a and Lipid Content of Chlorella sp.

Biodegradable wastes e.g. the outer cover of a boiled hen egg generally haphazardly discarded by humans in different locations of the country and generates problems for the local creatures. Although different researchers reported different methods to utilize the waste through the nanotechnological approach. Here, green synthesis of calcium oxide (CaO) nanoparticles from the hen eggshells was carried out and characterized them by using X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray (EDX) analysis, Fourier transform infrared spectroscopy (FTIR) and ultraviolet-visible spectrophotometer (UV). Further application of the synthesized nanoparticles was done on Chlorella sp. to investigate the impact on algal growth, lipid and chlorophylls. Synthesized CaO nanoparticles were applied in different concentration (0, 10, 20 and 30 mg L^–1) and readings were monitored for 20 days. The highest biomass concentration 242.56 mg L^–1 was achieved for the nanoparticle concentration of 20 mg L^–1 and the lipid content increased up to 35.71% in 20 mg L^–1. These results pave the way for enhanced algal biofuel production.