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ARS Home » Southeast Area » Oxford, Mississippi » Natural Products Utilization Research » Research » Publications at this Location » Publication #308052
Title: Arsenic speciation and fucoxanthin analysis from seaweed dietary supplements using LC-MS

Author
item KHAN, IKHLAS - University Of Mississippi
item WANG, YAN-HONG - University Of Mississippi
item AVULA, BHARATHI - University Of Mississippi

Submitted to: Journal of the Association of Official Analytical Chemists
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/25/2014
Publication Date: 3/12/2015
Publication URL: http://handle.nal.usda.gov/10113/62282
Citation: Khan, I.A., Wang, Y., Avula, B. 2015. Arsenic speciation and fucoxanthin analysis from seaweed dietary supplements using LC-MS. Journal of the Association of Official Analytical Chemists. 98(2):321-329.

Interpretive Summary: The developed analytical methods provided alternative fast and accurate methods for quality control and safety of seaweed samples and dietary supplements. The methods described were simple, rapid and reproducible. The study revealed that inorganic species [As(III) and As(V)] are the predominant chemical form of arsenic in all samples including dietary supplements analyzed. Inorganic arsenic species [As (III) and As(V)] accounted for 51-90% of the sum of the arsenic species detected. Analysis of 12 dietary supplements also showed varied fucoxanthin content which often differed markedly from label claims.

Technical Abstract: Inorganic species are considered more toxic to humans than organic arsenic and total arsenic. Analysis of total arsenic in metallic form, organic and inorganic arsenic species from seaweeds and dietary supplements using LC-ICP-MS was developed. Solvent extraction with sonication and microwave extraction using various aqueous and aqueous/solvent mixtures was evaluated. The sum of inorganic arsenic species present in the dietary supplements, ranged from 1.2 to 31 µg/day. Fucoxanthin, a carotenoid having pharmacological activities were analyzed using UHPLC-UV-MS. The content of fucoxanthin was found to be in the range from 0.025-0.035% and up to 3.6 mg/day in seaweed samples and dietary supplements, respectively. The data presented here will be valuable for the quality assurance of analytical method development and surveys of total arsenic and arsenic species in dietary supplements.