Total, free and conjugated forms (steryl esters, sterylglycosides and acyl steryl glycosides) of sterols from three microalgae that are extensively used in mariculture (Tetraselmis chuii, Nannochloropsis salina and Skeletonema costatum) were examined. The results revealed that cholesterol is the only common fraction detected in all investigated species and distributed in free and all conjugated forms. However, the total sterol content of T. chuii

The marine eustigmatophycean microalga Nannochloropsis (Monallantus) salina Hibberd was cultured with different concentrations (25, 50, 75 and 100%) of aqueous extract of diesel fuel oil for 15 days to assess the growth and some physiological responses of the miroalga to the pollutant stress. The growth data revealed a negative significant effect of the various pollutant concentrations on the algal cell number (P ≤ 0.05) whereas the correlation

The marine eustigmatophycean microalga Nannochloropsis (Monallantus) salina Hibberd was grown for 8 days in cultures to which various amounts of the aqueous extract of diesel fuel oil was added and the subsequent behaviour of the stressed growing cells was studied. The results revealed so as to by increasing the concentration of the pollutant there was a decrease in growth as measured by optical density and the deteriorating was maximum and accounted