Effect of tobacco smoke on the growth, biochemical composition, and biodiesel characteristics of two Chlamydomonas strains

Microalgae has been known as one of the efficient biological carbon dioxide (CO 2 ) sequesters. In recent years, they have been applied to improve the air quality by reducing CO 2 concentration and boosting oxygen (O 2 ) level, and have the ability to tolerate diverse toxic elements in the air. The current study investigates the effect of tobacco smoke on the growth, biochemical, and biodiesel characteristics of two Chlamydomonas strains. For this purpose, strains were exposed to seven days of tobacco smoke by burning one cigarette per hour in a closed box containing the air supply. CHL-2220 continued its proliferation without demonstrating any inhibition, while the growth of the other strain (CHL-2221) was inhibited severely. Tobacco smoke significantly altered the biochemical composition of CHL-2221, and caused the accumulation of more carotenoids and carbohydrates as part of the stress response. The analyzed biodiesel parameters presented poor quality from the extracted lipid of both strains. However, the fatty acid profile of the studied strain demonstrated their promising application as nutrient food supplements and feed for animals.