Determination of inorganic constituents in jellyfish

Abstract

We have determined the concentrations of inorganic components in jellyfish, such as Aurelia aurita (with and without aeration), Stomolophus nomurai, and dried sludge of Aurelia aurita using absorptiometry, flame photometry, ICP emission spectroscopy, atomic absorption spectrometry, or ion chromatography to examine the potential usefulness of jellyfish as a fertilizer for vegetable fields. The concentrations of the total nitrogen (9800 mg/kg), total phosphorus (19000 mg/kg), magnesium (17000 mg/kg), and calcium (27000 mg/kg) in the dried sludge of Aurelia aurita were 23, 1360, 14, and 96-times higher than those in Aurelia aurita (without aeration, 420, 14, 1200, and 280 mg/kg in fresh weight), respectively. Although the dried sludge of Aurelia aurita seemed to have some potential as a fertilizer, it contained high concentrations of iron (190000 mg/kg) and aluminum (2200 mg/kg), which might be undesirable for the growth of plants. On the other hand, the concentration of total nitrogen (750 mg/kg) in Stomolophus nomurai was 1.8-times higher than that in Aurelia aurita (without aeration), although the concentrations of total phosphorus (2.3 mg/kg) and calcium (75 mg/kg) were 1/6 and 1/4 of those in Aurelia aurita (without aeration). Stomolophus nomurai could also be expected to have potential as a fertilizer. Spinach was cultivated using a suspension of Aurelia aurita and Stomolophus nomurai, and the dried sludge of Aurelia aurita as a fertilizer. Stomolophus nomurai was most effective for the growth of spinach. The high concentrations of iron and aluminum in the dried sludge of Aurelia aurita seemed to decelerate the growth of spinach. © 2005 The Japan Society for Analytical Chemistry.