The effect of phosphate concentration on growth and agar content ofGelidium robustum(Gelidiaceae, Rhodophyta) in culture

✍ Scribed by Isabel Sousa-Pinto; Ray Lewis; Miriam Polne-Füller

• Publisher: Springer
• Year: 1996
• Tongue: English
• Weight: 544 KB
• Volume: 326-327
• Category: Article
• ISSN: 1573-5141
• DOI: 10.1007/bf00047843

✦ Synopsis

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 -') obtained at 150µM . 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 .