Effect of the extracts from the red alga, Spyridia filamentosa (Wulfen) Harvey, on the growth of the marine tropical species of Tetraselmis (Chlorophyta)
2006
Luong-Van, J.T.
The aim of this work was to examine the possibility of using the water-soluble and particulate fractions of Spyridia filamentosa as a source of nutrients for the growth of the tropical marine green microalga, Tetraselmis. Frozen thalli of the seaweed were thawed in sterile filtered seawater and ground in a mortar with pestle at room temperature for 30 min. The resulting slurry was then centrifuged (3000 rpm for 10 min), separating it into two fractions: the top pink supernatant (0D545 nm = 0.36) and the particulate fraction (7.5) mg dry weight per ml. In separate experiments, portions of the supernatant and particulate fractions, together with Tetraselmis cells, were placed in containers containing sterile filtered seawater and 1/50 amounts of fsub2 nutrients. It was found that the addition of the supernatant fraction of the S. filamentosa water extract at 0.05 m/ per ml of culture medium increased the cell density Tetraselmis, after 10 days of growth at 25 deg C and 80 micromoles photon/sq m/s, by two-fold (mean = 2.33, SD = 0.37, n = 3) over the control treatment. In contrast, the particulate fraction did not have the same effect as the former. Moreover, at the particulate fraction did not have the same effect as the former. Moreover, at concentrations greater than 56 micro g/ml, the particulate fraction inhibited motility and growth of Tetraselmis cells. Future work will elucidate the mechanisms for this dispartate effect of the two fractions of the extracts S. filamentosa on the growth of Tetraselmis and other microalgae.
显示更多 [+] 显示较少 [-]