The protective role of Spirulina platensis against the alterations in some biomarkers in crayfish (Procambarus clarkii) exposed to polyethylene nanoplastics

Abstract This work aims to elucidate the potential of Spirulina platensis (SP) to hinder the accumulation of polyethylene nanoparticles (PE-NPS) in crayfish ( Procambarus clarkii ) and to reduce their detrimental impacts. Four groups (control (only food), PE-NP S (10 mg/L), PE-NPS (10 mg/L) + S. platensis, and only S. platensis in the last group) were studied. The group exposed to PE-NP S only showed: (1) an increase in oxidative stress enzymes (the superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione (GSH), and total active cannabinoids (TAC)); (2) a decrease in the activity of the nervous and immune system enzymes (nitric oxide (NO), acetylcholinesterase (AchE), lysozyme activities LYZ, phenoloxidase (POX), and acid phosphatase (ACP)); and (3) a reduction in the hemocyte counts as a circulatory system marker. In the group treated with PE-NPs + S. platensis, there was a positive effect on: (1) the oxidative stress enzymes which reduced by almost 9%; (2) the neurological parameters have shown a significant increase by around 10.5%; the immune parameters (LYZ and ACP) showed a slight increase by almost 6.5%, while the POX enzyme elevated by 18% till reached its normal activity, and (3) the hemocyte counts increased significantly by 18%. The results illustrate the ability of S. platensis to reduce the adverse impacts of PE-NPs on crayfish.