Bioremediation of Crude Oil Emulsion in Seawater Using Chlorella sp.

Abstract:

Oil spills from sources such as rigs, tankers, and offshore platforms present significant environmental, economic, and social challenges. Large spills endanger human health by contaminating ecosystems. The emulsification of crude oil from the oil spill in seawater complicates remediation efforts, highlighting the need for a better understanding of factors influencing bioremediation strategies. Recently, Chlorella sp. proven to enhance the crude oil degradation by promoting the activity of indigenous microorganisms, utilizing nutrients from the oil and mitigating toxicity. This study investigates the effects of varying salinities on the growth of Chlorella sp. and its biodegradation efficiency under different crude oil concentrations. There are three experimental mixtures that were prepared: 100% seawater, 50% seawater/50% freshwater, and 100% freshwater. Each mixture received essential minerals and periodic CO₂ tablet additions to enhance growth. Optical density readings were taken every three days over a 15-day period at a controlled temperature of 30°C to assess growth rates. The results indicated that the presence of seawater significantly enhanced Chlorella sp. growth, yielding greater biomass compared to freshwater only. Additionally, Chlorella sp. effectively degraded crude oil components, with optimal degradation at lower concentrations (2%). Fourier Transform Infrared (FTIR) analysis revealed a significant reduction in hydrocarbon peaks over two weeks. However, higher crude oil concentrations (4%) negatively impacted the algae growth due to the heightened nutrient requirements necessary for Chlorella sp. to perform efficient biodegradation. This study highlights the potential of Chlorella sp.for bioremediation in oil spill scenarios.

• Periodical: Advanced Materials Research (Volume 1184)
• Pages: 61-69
• DOI: https://doi.org/10.4028/p-0H4clh
• Online since: November 2025
• Authors: Iffah Hazieqah Yunos, Mohd Syahlan Mohd Syukri*, Mohd Adly Mohd Ibrahim, Norfazliana Abdullah
• Keywords: Bioremediation, Chlorella sp., Oil Spills, Petroleum Hydrocarbon

References

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DOI: 10.18356/9789210021784c007