Physiological resilience of freshwater microalgae Chlorella sorokiniana under NaCl stress supplemented with sodium sulfate as a mitigating agent
摘要
Microalgae exhibit remarkable resistance to abiotic stresses, such as salinity. This work investigates the effects of sodium sulfate (Na2SO4) and sodium chloride (NaCl) on the freshwater microalgal strain Chlorella sorokiniana with particular emphasis on physiological activities. The study is focused on understanding the molecular processes of C. sorokiniana in a controlled environment using NaCl and equimolar concentrations of NaCl and Na2SO4. Certain biochemical assays resulted in C. sorokiniana cultured with a salt mixture of 350 mM (NaCl + Na2SO4), showed better growth than 350 mM NaCl. ROS production was high in 350 mM NaCl, which was 1.71 and 1.95 times higher than in the control and in equimolar NaCl + Na2SO4, respectively. The osmolyte level in 350 mM NaCl increased by 2.9 and 2.29-fold as compared to the control and equimolar concentration of NaCl + Na2SO4, respectively. Significant alterations in protein expression suggested that stress-response pathways have been activated. Furthermore, significant fluctuations in osmolyte and antioxidant levels indicate the significant adaptation of the microalgae to salinity stress. These findings contribute to the optimization of microalgae farming by shedding light on the physiological and biochemical strategies of microalgae in saline environments, which are essential to comprehend in order to advance sustainable biotechnological applications.