Abstract
In order to clarify the mechanism of growth of musty-odor producing cyanobacteria, the effects of six chelating agents such as EDTA (Ethylenediaminetetraacetic acid), EDTA {Diethylenetriamine-N, N, N', N'', N''-pentaacetic acid}, EDDHA {Ethylenediaminedi (ohydroxyphenylacetic acid) }, HBED {N, N'-bis (2-hydroxylbenzyl) ethylenediamine-N, N'diacetic acid}, DESF (Desferrioxamine B), BPDS (Bathophenanthrolinedisulfonate), on the growth of Oscillatoria brevis were studied using laboratory cultures.
O.brevis grew well in the presence of 1: 1Fe chelates (molar ratio of chelator to Fe) of DTPA, EDDHA and HBED as the iron sources. O. brevis was able to grow in the presence of DTPA at least up to 15-fold, EDDHA up to 16-fold and HBED up to 5-fbld for Fe (molar ratio), respectively. O. brevis also could utilize FeII (BPDS) 3 as the iron source in the presence of DTPA, EDDHA and HBED. In addition, it was capable of utilizing Fe (III) -DESF as the iron source in the presence of EDDHA and HBED.
The present studies and previous results {Nakashima and Yagi, Water Sci. Technol., 25 (2), 207 (1992) } indicate that O.brevis can utilize a wide variety of iron forms as the iron sources and more excellent ability of iron absorption compared with Oscillatoria tenuis, Anabaena macrospora and Phormidium tenue isolated from Lake Biwa.
