Abstract
Phosphate concentration of the growth medium was found to affect the growth rate and agar yield of a clone of Gelidium robustum grown in the laboratory. To study differences in growth we used phosphate concentrations from 0 to 200 µM. To determine the effect of phosphate on agar yield and its properties we used concentrations from 0 to 20 µM. Growth rates generally increased with increasing phosphate concentration, with the highest growth rate (21% d−1) obtained at 150 µM. Agar yield as percentage of fresh weight was highest (10%) in the algae grown with low phosphate concentrations, but agar yield as percentage of dry weight was highest(43%) at 20 µM of phosphate. Gel strength increased with phosphate concentration with a maximum of 160 g m−2 for 0.75% gels for the cultures at 20 µM. Melting and gelling temperatures of the gels were also affected by phosphate concentration of the growth medium. Starch yield was highest in algae grown in low phosphate concentrations.
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Sousa-Pinto, I., Lewis, R. & Polne-Füller, M. The effect of phosphate concentration on growth and agar content of Gelidium robustum (Gelidiaceae, Rhodophyta) in culture. Hydrobiologia 326, 437–443 (1996). https://doi.org/10.1007/BF00047843
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DOI: https://doi.org/10.1007/BF00047843