Cultivation of Chlorella vulgaris in Anaerobically Digested Dairy Manure Wastewater (ADDMW) for Protein and Chlorophyll Production

Chlorella vulgaris is a eukaryotic, unicellular green microalgae that can be harvested as protein source since it can contain protein up to 50% of its dry weight. However, its cultivation is costly due to the price of its growth medium. In this research we used bioslurry or known as anaerobically digested dairy manure wastewater (ADDMW) as growth medium for C. vulgaris, since dairy manure is known to contain high nitrogen and phosphorus and its availability relatively abundant in rural areas. The cultivation of C. vulgaris in the ADDMW medium was conducted in lab-scale (19 L) photobioreactors. After 14 days the culture was able to produce chlorophyll content of 34.62 μg/mL, and after 28 days was able to produce protein up to 35% dry weight. Moreover, C. vulgaris was also able to reduce PO4-P, NH4-N and NO3-N levels in ADDMW by 45.95, 78.24 and 17.38%, respectively.