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Updated: Apr 17, 2026

Determination of Total Lipid and Lipid Classes in Marine Samples
Published on: December 11, 2021
Sterols as biomarkers in the surface microlayer of the estuarine areas
Murad Ali Alsalahi1, Mohd Talib Latif2, Masni Mohd Ali3
1School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia; Department of Marine Chemistry and Pollution, Faculty of Marine Science and Environment, Hodeidah University, Yemen.
Abstract:
This study aims to determine the concentration of sterols used as biomarkers in the surface microlayer (SML) in estuarine areas of the Selangor River, Malaysia. Samples were collected during different seasons through the use of a rotation drum. The analysis of sterols was performed using gas chromatography equipped with a flame ionisation detector (GC-FID). The results showed that the concentrations of total sterols in the SML ranged from 107.06 to 505.55 ng L(-1). The total sterol concentration was found to be higher in the wet season. Cholesterol was found to be the most abundant sterols component in the SML. The diagnostic ratios of sterols show the influence of natural sources and waste on the contribution of sterols in the SML. Further analysis, using principal component analysis (PCA), showed distinct inputs of sterols derived from human activity (40.58%), terrigenous and plant inputs (22.59%) as well as phytoplankton and marine inputs (17.35%).
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