Efficiency of Microalga Dunaliella tertiolecta in Cultivation and Removal of Pollutants from Dairy Industry Wastewater
نویسندگان
1 Department of Fisheries, Faculty of Natural Resources, University of Zabol
2 Department of Fisheries, Faculty of Natural Resources, University of Zabol
3 Faculty of Sciences, University of Sistan and Baluchestan, Zahedan, Iran
4 Department of Fisheries, Faculty of Natural Resources, University of Zabol
5 Department of Aquatic Science, Hamoun International Wetland Institute, Research Institute of Zabol, Zabol, Iran.
doi
10.48308/pae.2025.240751.1118چکیده
Dunaliella tertiolecta is increasingly recognized as a valuable bioindustry microalga due to its ability to produce high-value pigments and biologically active compounds. However, the high cost of conventional culture media remains a major challenge for its large-scale cultivation. To address this issue, using nutrient-rich industrial wastewaters, such as dairy effluent, offers a promising, sustainable, and economical alternative. This study investigated the growth performance and pigment production of D. tertiolecta cultivated for 21 days in five concentrations of dairy wastewater (0%, 25%, 50%, 75%, and 100%) under controlled laboratory conditions (light intensity of 2500 lux; salinity of 1.5 M; temperature of 25 ± 2°C; pH of 7.5 ± 0.15). Algal cell density, chlorophyll a, chlorophyll b, and carotenoid content were measured every three days, while levels of ammonia, nitrate, and phosphate were assessed every five days. The results showed that the 25% wastewater treatment (T2) produced the highest cell density on day 12 (54.20 × 106 ± 1 cells/mL). This treatment also resulted in the highest pigment concentrations, with chlorophyll a at 2.76 ± 0.04 mg/mL, chlorophyll b at 7.24 ± 0.06 mg/mL, and carotenoids at 2.24 ± 0.06 mg/mL concentrations. In terms of nutrient removal, T2 achieved the greatest reduction in phosphate (0.052 ± 0.02 mg/mL) and nitrate (0.059 ± 0.94 mg/mL), while the highest ammonia removal (0.062 ± 2.23 mg/mL) occurred in the 50% treatment (T3). Overall, the findings indicate that dairy wastewater, when properly diluted, can serve as an effective and low-cost culture medium for D. tertiolecta, supporting both biomass production and wastewater bioremediation.