Autori: Nagwa Gamal Mohammady

Editorial: Oceanologia, 47(1), p.75-92, 2005.

Rezumat:

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 coefficient (r) was highly significant towards all treatment concentrations, since it ranged from 0.95-0.98. Furthermore, the logarithmic grown algal cells were examined for their chlorophyll a content, β- glucan, amino acid pool, C/N ratio and the element composition. According to our results, the algal cells were significantly affected by the pollution (P ≤ 0.05) towards different physiological parameters and this significant may be negative, positive or variable. Therefore, a negative effect of the pollutant on the cellular β-glucan and the total amount of amino acids were obviously shown; however, the composition of cellular amino acid pool was not affected. A positive effect of the pollutant on the chl (a) and C/N ratio. In addition, a significant variation on the element composition as revealed by energy-dispersive X-ray microanalysis was observed, in addition to, an existence correlation between different elements was statistically reported. However, a final conclusion was discussed.

Cuvinte cheie: Diesel fuel pollution, Physiological responses, Nannochloropsis salina.