Evaluation of astaxanthin biosynthesis by Haematococcus pluvialis grown in culture medium added of cassava wastewater

The effluent generated with cassava roots processing for flour production is a major contributor to serious environmental impacts when disposed of into water bodies, posing risks to public health and aquatic communities. To minimize these impacts, this study aimed to assess the cell growth and astaxanthin biosynthesis of the microalgae Haematococcus pluvialis cultivated with cassava wastewater (CW) added to the BBM culture medium. The H. pluvialis cell growth and astaxanthin content were assessed by supplementing culture medium with CW concentrations at 2.5, 5, and 10% (v/v). The CW samples were collected in locations of the State of Santa Catarina, Brazil: Imarui (IMA), Jaguaruna (JAG), and Paulo Lopes (PLO). The cell density of H. pluvialis showed that the concentration of 2.5% of effluent from JAG and PLO samples obtained the best growth results. The astaxanthin content produced by adding 2.5 and 5% of effluent from JAG and PLO were statistically higher (p < 0.05) to the control treatment, which was performed without effluent addition. These results demonstrate that CW can stimulate astaxanthin accumulation in this algae, suggesting that CW usage in H. pluvialis cultivation aiming astaxanthin biosynthesis can minimize damages caused by this agro-industrial effluent.

Automated summary

The study evaluated the impact of using cassava wastewater on the growth and astaxanthin synthesis of Haematococcus pluvialis, demonstrating that CW can stimulate astaxanthin accumulation in this algae and help minimize environmental damage caused by agricultural effluents.