Optimization of Chlorella-Biomass Production Using Domestic and Restaurant Waste Water as a Potential Feedstock

Abstract

The quest to invent a cost-effective media for commercial cultivation of microalgae biomass has remained a cause for motivation for quite some time now. In this study domestic and restaurant wastewater were obtained from Choba, Rivers State Nigeria. The biosafety of the wastewater was ascertained and prepared as a media for the cultivation of microalgae. The samples were prepared in 180:20, 160:40, 140:60, 120:80, and 100:100 ratios using pond water and mixture of domestic and restaurant wastewater respectively. The blooming process was observed for seven days and biomass was monitored by cell optical density and dry weight. The result revealed that biosafety evaluation saw a reduction from 120cfu/ml to 0cfu/ml on the third day. The optimal wavelength selected for growth monitoring was 620nm while growth media ratio selected was 120:80 for restaurant:domestic wastewater. The optimization revealed pH 6.0, temperature 300C, salinity 10ppm and photoperiod 12:12 day:night as optimal condition. Domestic wastewater can be a veritable medium for cultivation of Chlorella sp as a means of integrated waste management; the Chlorella biomass can be used as a feedstock for various biotechnological applications such as source of biochemical, nutraceuticals and for use in biofuel generation.