Dried Green and Purple Lavers (Nori) Contain Substantial Amounts of Biologically Active Vitamin B12 but Less of Dietary Iodine Relative to Other Edible Seaweeds

• Published in: Journal of agricultural and food chemistry Vol. 47; no. 6; pp. 2341 - 2343
• Main Authors: Watanabe, Fumio, Takenaka, Shigeo, Katsura, Hiromi, Masumder, S. A. M. Zakir Hussain, Abe, Katsuo, Tamura, Yoshiyuki, Nakano, Yoshihisa
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 14.06.1999
• Subjects: bioassays; Biological and medical sciences; chemical analysis; chemiluminescence; dried edible seaweeds; Enteromorpha; Food industries; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; green seaweeds; iodine; Lactobacillus; Lactobacillus leichmannii; macroalgae; nutrient content; Porphyra; Research and development. New food products, dietetic foods and beverages; vitamin B12; vitamin content; Vitamin; Marine plant; Porphyra; Microbiological method; Bacteria; Lactobacillaceae; Thallophyta; Iodine; Rhodophyta; Biochemical analysis; Bioassay; Algae; Nutritive value; Vegetarian diet; Chemiluminescence; Bioavailability; Experimental study; Cyanocobalamin; Bangiophyceae; Edible alga; Vertebrata; Intrinsic factor; Mammalia; Lactobacillus delbrueckii subsp. lactis; Trace element (nutrient); Comparative study
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf981065c

Vitamin B12 concentrations of dried green (Enteromorpha sp.) and purple (Porphyra sp.) lavers (nori) were determined by both Lactobacillus leichmannii ATCC 7830 microbiological and intrinsic factor chemiluminescence methods. The values determined by using the microbiological method (63.58 ± 2.90 and 32.26 ± 1.61 μg/100 g of dry weight) were identical to those found by using the chemiluminescence method (69.20 ± 2.21 and 25.07 ± 0.54 μg/100 g of dry weight) in both dried green and purple lavers, respectively. A silica gel 60 thin-layer chromatography of both laver extracts shows that non-coenzyme forms (hydroxo and cyano forms) of vitamin B12 predominate in both dried lavers. The dried lavers contained lesser amounts of dietary iodine (∼4−6 mg/100 g of dry weight) relative to other seaweeds, suggesting that excessive intake of the dried lavers is unlikely to result in harmful intake of dietary iodine. These results indicate that the dried lavers (nori) are the most excellent source of vitamin B12 among edible seaweeds, especially for strict vegetarians. Keywords: Vitamin B12; dried edible seaweeds, green and purple lavers; nori; intrinsic factor; Lactobacillus leichmannii; dietary iodine; vegetarians