Biochemical composition of the copepod euterpina acutifrons from the Coastal waters of alexandria

Abstract

Protein, carbohydrate and lipid contents were determined in the most numerous and wide spread copepod Euterpina acutifrons collected from the coastal waters of Alexandria. Protein is the major biochemical component of the copepod constituting on the average 35.2 ± 6.7% of the organisms' dry weight followed by carbohydrate (7.9 ± 1.6%) and lipid (3.7 ± 1.9%) contents. Organisms collected from the Eastern Harbor (eutrophic basin) affected by sewage discharge were characterized by high biochemical contents while opposite to landbased sources affected by industrial discharge, the organisms' biochemical components were at a minimum. Compared to other representatives of the zooplankton community, Euterpina retains high protein content indicating its suitability as food for marine fishes. The step wise multiple regression equations revealed that the different biochemical components of Euterpina are mostly affected with the occurrence of available food represented by chlorophyll a concentrations. The average Protein/Carbohydrate ratio for E. acutifrons i.e. 4.46 ± 2.3 indicate that the organism is inhabiting a nutrient sufficient environment. Lipid/protein ratios more than 0.2 observed at industrial discharge affected areas indicate pollution impact on protein production.