Iron-59 absorption from soy hulls: intrinsic vs extrinsic labeling

Conference · Wed Mar 05 04:00:00 EST 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:6935701

Lykken, G I; Mahalko, J R; Nielsen, E J; Dintzis, F R

As part of an evaluation of the validity of the extrinsic labeling technique for measuring iron absorption, absorption from soy hulls extrinsically labeled (/sup 59/Fe added to bread dough) was compared with that from soy hulls intrinsically labeled (/sup 59/Fe incorporated into the soy plant during growth). Century soybeans were grown in a greenhouse. After pods had formed and were filling, each plant was stem injected twice, at 3 day intervals, with 22 ..mu..Ci /sup 59/Fe as FeCl/sub 2/ in 25 ..mu..l of 0.5 M HCl solution. After the plants had senesced, the soybeans were harvested, dried, shelled and the hulls removed. Standard meals containing 3.5 mg Fe/meal and up to 0.06 ..mu..Ci /sup 59/Fe in a soy hull bun were fed on 2 consecutive days to free-living volunteers in a crossover design. Absorption of /sup 59/Fe was greater from intrinsically labeled soy hulls than from extrinsically labeled soy hulls, 20 +/- 20% vs 15 +/- 11% (n=14, p > 0.05 by paired t-test). Apparent absorption ranged from 1.3% to 77% from intrinsically labeled soy hulls and .5% to 29% from extrinsically labeled soy hulls with the highest absorption occurring in persons with low serum ferritin (S.F. < 8 ng/ml). These findings provide additional evidence that the extrinsic labeling method is a valid measure of iron bioavailability to humans.

• Research Organization: Univ. of North Dakota, Grand Forks
• OSTI ID: 6935701
• Report Number(s): CONF-8604222-
• Conference Information: Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Journal Volume: 45:4
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ABSORPTION
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL AVAILABILITY
DAYS LIVING RADIOISOTOPES
ELEMENTS
EVEN-ODD NUCLEI
FOOD
INTERMEDIATE MASS NUCLEI
INTESTINAL ABSORPTION
IRON
IRON 59
IRON ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
METALS
NUCLEI
PLANTS
RADIOISOTOPES
SOYBEANS
TRACER TECHNIQUES
TRANSITION ELEMENTS
UPTAKE
VEGETABLES