Assessment of hydrocarbon degradation capacity and kinetic modeling of and for crude oil phycoremediation under mixotrophic conditions.

Crude oil spills imperil aquatic ecosystems globally, prompting innovative solutions such as microalgae-based bioremediation. This study explores the potential of and , for crude oil spill phycoremediation under mixotrophic conditions and varying crude oil concentrations (0.5-2%). demonstrated notable resilience, thriving up to 1% crude oil exposure, while adapted to lower concentrations. Optimal growth for both was observed at 0.5% exposure. Chlorophyll a content in increases at 0.5% exposure but declines above 1%, while a decline was noticeable in chlorophyll b in treatment groups above 1%. Carotenoid levels varied, displaying the highest levels at higher concentrations above 1.5%. Similarly, showed increased chlorophyll a content at 0.5% exposure, with stable carotenoid levels and a decline in chlorophyll b content at higher concentrations. GC/MS analyses indicated efficiently degraded aliphatic compounds like decane and tridecane, surpassing in degrading both aliphatic and aromatic hydrocarbons. Growth kinetics was best represented by the modified Gompertz and logistic models. These findings highlight the species-specific adaptability and optimal concentration for microalgae to degrade crude oil effectively, advancing phycoremediation processes and strategies critical for environmental restoration.