The removal of sodium (Na) from seawater using two photosynthetic bacteria was investigated using Rhodobacter sphaeroides SSI (SSI) and Rhodovulum sp. which is a marine photosynthetic bacterium. Both Rhodovulum sp. an...The removal of sodium (Na) from seawater using two photosynthetic bacteria was investigated using Rhodobacter sphaeroides SSI (SSI) and Rhodovulum sp. which is a marine photosynthetic bacterium. Both Rhodovulum sp. and acclimated SSI were shown to grow well in a 3% NaCl supplemented glutamate-malate medium. The maximum rate of Na removal was 39.3% by SSI and 64.9% by Rhodovulum sp. after two days cultivation under static light conditions. However, Na was re-released back into the medium after two to three days. When a nutrient-supplemented seawater medium (3.3% NaCl, 13.10 gNa/l) was used, the maximum Na removal rates were 30.3% (9.05 gNa/l) by SSI and 48.9% (6.69 gNa/l) by Rhodovulum sp., under static light conditions. Similar growth and Na removal rates were found under aerobic dark cultivation. In this case, no re-release of Na was observed with either bacterium. Two stages culturing was conducted first, with Rhodovulum sp. and then with SSI replacement. The Na concentration was reduced to 0.79 gNa/l (94.0% removal) after cultivation for eight days under aerobic darkconditions. The supernatant was applied successfully as a liquid fertilizer in the cultivation of Japanese radish.展开更多
文摘The removal of sodium (Na) from seawater using two photosynthetic bacteria was investigated using Rhodobacter sphaeroides SSI (SSI) and Rhodovulum sp. which is a marine photosynthetic bacterium. Both Rhodovulum sp. and acclimated SSI were shown to grow well in a 3% NaCl supplemented glutamate-malate medium. The maximum rate of Na removal was 39.3% by SSI and 64.9% by Rhodovulum sp. after two days cultivation under static light conditions. However, Na was re-released back into the medium after two to three days. When a nutrient-supplemented seawater medium (3.3% NaCl, 13.10 gNa/l) was used, the maximum Na removal rates were 30.3% (9.05 gNa/l) by SSI and 48.9% (6.69 gNa/l) by Rhodovulum sp., under static light conditions. Similar growth and Na removal rates were found under aerobic dark cultivation. In this case, no re-release of Na was observed with either bacterium. Two stages culturing was conducted first, with Rhodovulum sp. and then with SSI replacement. The Na concentration was reduced to 0.79 gNa/l (94.0% removal) after cultivation for eight days under aerobic darkconditions. The supernatant was applied successfully as a liquid fertilizer in the cultivation of Japanese radish.
