Investigating the effect of phenanthrene and anthracene on biochemical compounds and growth in Spirulina platensis algae(J. Leonard, 1960) Arthospira-sp

Polyaromatic hydrocarbons (PAH) with a benzene ring are petroleum compounds and are known as the most important cause of environmental pollution. Phenanthrene and anthracene are PAHs found in the aquatic environment. In the present study, the effect of these two substances on a freshwater algae, Spirulina platensis, was investigated at biochemical levels. Algae mass cultivation was performed in laboratory conditions in nine treatments and 27 repetitions of anthracene (5, 25, 50, 250 mg/l) and phenanthrene (10, 50, 100, 500 mg/l) for 72 h. A control treatment with no anthracene and phenanthrene was also considered. The amount of malondialdehyde (MDA) in the treatment of phenanthrene and anthracene increased compared to the control treatment, which was significant at the 5% level, but the amount of MDA in the treatment of phenanthrene at a concentration of 10 mg/L did not show a significant difference (P>0.05). Sugar content showed a significant difference except in the concentration of 10 mg/liter of phenanthrene (P<0.05). Proline content increased significantly in response to both hydrocarbons (P<0.05), There was a significant increase in proline in both anthracene and phenanthrene treatments compared to the control group at a probability level of 5%. Catalase activity showed significant changes between the treatments compared to the control (P<0.05). The amount of total protein significantly increased in phenanthrene stress and significantly decreased in anthracene stress in all concentrations compared to the control group (P<0.05). The results showed that both hydrocarbon substances at different concentrations had significant effects on the biochemical characteristics of spirulina algae.