Nitrate, Nitrite, and Iodine Concentrations in Commercial Edible Algae: An Observational Study.

Edible algae are a natural source of nutrients, including iodine, and can also contain nitrogen in the form of nitrate (NO) and nitrite (NO) as they can fix nitrogen from seawater. This study aimed to analyse the NO, NO, and iodine concentrations in eighteen macroalgae and five microalgae species commercially available in the United Kingdom. NO and NO concentrations were measured using high-performance liquid chromatography (HPLC), and iodine was determined using inductively coupled plasma mass spectrometry (ICP-MS). NO and iodine concentrations in macroalgae (NO: 4050.13 ± 1925.01 mg/kg; iodine: 1925.01 ± 1455.80 mg/kg) were significantly higher than in microalgae species (NO: 55.73 ± 93.69 mg/kg; iodine: 17.61 ± 34.87 mg/kg; < 0.001 for both). In the macroalgae group, nori had the highest NO (17,191.33 ± 980.89 mg/kg) and NO (3.64 ± 2.38 mg/kg) content, as well as the highest iodine content. Among microalgae, had the highest concentration of NO (223.00 ± 21.93 mg/kg) and iodine (79.97 ± 0.76 mg/kg), while had the highest concentration of NO (7.02 ± 0.13 mg/kg). These results indicate that commercially available edible algae, particularly macroalgae species, could be a relevant dietary source of NO and iodine.