Expired Study
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Boston, Massachusetts 02111


The goal of this protocol is to determine the vitamin A value (equivalence) of spirulina. The investigation will use intrinsically deuterium labeled spirulina and an isotope vitamin A reference dose, 13C10- retinyl acetate (13C10 RAc), in males (n=20). Up to 45 blood samples (10 ml/sample) will be collected from each subject over a two-month period to evaluate the bioavailability and bioconversion of spirulina ß-carotene to vitamin A.

Study summary:

By utilizing novel stable isotope dilution techniques recently developed in our laboratory, we will trace deuterium labeled ß-carotene in intrinsically labeled spirulina, which is harvested from a hydroponic system. In the mean time, we will track 13C10 labeled vitamin A in humans. In this way we will determine absorption of ß-carotene from spirulina matrix and the conversion of the spirulina ß-Carotene to retinol. This will enable us quantitatively determine the vitamin A equivalence of spirulina. The specific aims of this study are: 1. To determine labeled ß-C blood response kinetics following an acute dose of intrinsically labeled spirulina; 2. To determine labeled retinol blood response from the intrinsically labeled spirulina; 3. To determine 13C10 retinol blood response from the isotope reference material 13C10 retinyl acetate; 4. To determine s spirulina-vitamin A equivalence.


Inclusion Criteria: - Healthy volunteer Exclusion Criteria: - Not has GI track problems - Any medical condition that will affect the intestinal absorption



Primary Contact:

Principal Investigator
Guangwen Tang, Ph.D.
USDA Human Nutrition Research Center on Aging, Tufts University

Backup Contact:


Location Contact:

Boston, Massachusetts 02111
United States

There is no listed contact information for this specific location.

Site Status: N/A

Data Source: ClinicalTrials.gov

Date Processed: October 09, 2019

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