Effect of the cooking procedure on the arsenic speciation in the bioavailable (dialyzable) fraction from seaweed

Determination of Arsenic Species in Edible Seaweeds by HPLC–ICP-MS After Pressurized Hot Water Extraction

“…High arsenic concentrations were obtained for the Kombu (55.6 µg g -1 ) and Nori (39.4-54.4 µg g -1 ) samples. Those levels are in agreement with reported data for Atlantic seaweeds (5,6,8,32). The lowest arsenic value (7.8 µg g -1 ) was found in cooked and canned seaweed (Sea Spaghetti and Furbelows), which could be due to the fact that arsenic dissolves into the cooking water (8,33).…”

“…Keeping in mind the sample weight, the LODs and LOQs, expressed as ng g -1 (Table III), are low enough to perform arsenic speciation in the seaweed samples (LOQs ranging from 46.9 to 269 ng g -1 ). Table II, arsenosugar retention times were assigned after analysis of a lyophilized algal extract of Fucus serratus (containing the four arsenosugars: Gly-Sugar, PO 4 -Sugar, SO 3 -Sugar, and SO 4 -Sugar) kindly donated by Professor Dr. K. A. Francesconi (Karl-Franzens University, Graz, Austria) (8). Also, arsenosugar identification was confirmed after electrospray ionization tandem mass spectrometry (ESI-MS/MS) with two-dimensional HPLC (size exclusion, followed by anion exchange) (7).…”

“…The wide-ranging levels of toxicity exhibited by different arsenic species have led to the development of several analytical methods for their extraction and quantification. Arsenic speciation studies focusing mainly on different edible seaweeds include Nori (3)(4)(5)(6)(7)(8), Wakame (4-9), Hijiki (4,5,(10)(11)(12), Fucus (5,13 ), Sea Spaghetti (5), Kombu (5,7,8), Laminaria (5,6), Sargaso (5,6), Sea Lettuce (7,8,13) or Codium (13). The arsenic content in other algae and seaweeds were reported by Arame (5), Hypnea (13), Cladophora and Chara (14), Turner (15), and Kelp (16).…”

“…The arsenic content in other algae and seaweeds were reported by Arame (5), Hypnea (13), Cladophora and Chara (14), Turner (15), and Kelp (16). In addition, bioaccessibility and bioavailability studies were developed to assess the bioavailability ratios of toxic and non-toxic arsenic species in edible seaweeds (4,7,8,17).…”

“…Typical extraction times reported are 15 minutes (3,4,16), 30 minutes (11), 60 minutes (7,8), or 180 minutes (9) for ultrasound-assisted extraction (UAE); 5 minutes (12), 15 minutes (5), and 30 minutes (6) for microwaveassisted extraction (MAE); or 120 minutes (18), overnight (15), and 16 hours (13,14) for shaking procedures. Also, the use of large amounts of solvents [de-ionized water (DIW) (5,9,(11)(12)(13)(14)18), methanol (MeOH)/DIW mixtures (3,4,15,16), ammonium carbonate (6) or ammonium acetate (7,8) buffers] and extract handling (centrifugation steps are required) before analysis are other important disadvantages of these classical procedures. There is, therefore, an interest in developing automated, rapid extraction, and green methods that guarantee high recovery of the analytes.…”