Green solutions: evaluating the impact of Chlorella sorokiniana and Anabaena laxa on captan phycoremediation

This study explores the use of algae for phycoremediation, focusing on how Chlorella sorokinianaand Anabaena laxa detoxify water contaminated with captan, a common fungicide. The efficiencyof these species in absorbing captan and the associated biochemical changes were evaluated toassess their potential for environmental protection. Microalgae were exposed to captan concentrationsof 15 and 30 mg/L, and various parameters, including captan uptake, chlorophyll (Chl) a, carotenoidlevels, and changes in metabolic profiles (soluble carbohydrates, organic acids, amino acids, andfatty acids), were measured. Results showed Anabaena had a higher captan absorption capacity(141.7 µg/g at 15mg/L and 239.3 µg/g at 30mg/L) compared to Chlorella (74.43 µg/g and 162 µg/g).Increased captan uptake reduced the growth of both species, as indicated by lower Chl a levels.Both species accumulated osmo-protectants and antioxidants as defense mechanisms, with solublesugars increasing by 83.49% in Chlorella and 68.87% in Anabaena, and carotenoids increasing by60.42% and 46.24%, respectively. Principal component analysis revealed distinct species-levelresponses, with Anabaena showing greater tolerance. The study concludes that both species caneffectively remediate captan, with Anabaena being more efficient, indicating their potential formitigating agrochemical impacts in aquatic environments and promoting sustainable agricultureand water management.