glucocorticoid receptor. Glucocorticoids are natu-
rally–produced steroid hormones, that inhibit the
process of inflammation. Their shape permits them
to move across the membrane that surrounds cells in
the body, and to be recognized by molecules inside the
cell called glucocorticoid receptors.
DescriptionThe body absorbs molybdenum quickly in the
stomach and in the small intestine. The mechanism
of absorption is uncertain. Following absorption,
molybdenum is transported by the blood to the liver
and to other tissues of the body. In the molybdate
form, it is carried in the blood bound to alpha–macro-
globulin and by adsorption to red blood cells. The
liver and kidney store the highest amounts of molyb-
denum. The molybdenum cofactor is made in cells and
consists of a molybdenum atom bound to tricyclic
pyranopterin molecules, the simplest of which is
known as molybdopterin. The cofactor is a compo-
nent of four main enzymes:
Sulfite oxidase. This enzyme catalyzes the transfor-
mation of sulfite to sulfate, a reaction that is neces-
sary for the metabolism of sulfur–containing amino
acids, such as cysteine.
Xanthine oxidase. This enzyme catalyzes the break-
down of nucleotides (precursors of DNA and RNA)
to form uric acid, which contributes to the antioxi-
dant capacity of the blood.
Aldehyde oxidase. This enzyme is involved in several
reactions, including the catabolism of pyrimidines.
Xanthine dehydrogenase. This enzyme catalyzes the
conversion of hypoxanthine to xanthine, and xan-
thine to uric acid.
Aldehyde oxidase and xanthine oxidase catalyze
hydroxylation reactions involving a number of differ-
ent molecules with similar structures. Xanthine oxidase
and aldehyde oxidase also play a role in themetabo-
lismof drugs and toxins. However, according to the
Micronutrient Information Center of the Linus Paul-
ing Institute of Oregon State University, only sulfite
oxidase is known to be crucial for human health.
Sources of dietary molybdenum include milk,
dried beans, peas, nuts and seeds, eggs, liver tomatoes,
carrots and meats. The molybdenum contents are per
cup:
Navy beans: 196mg
Black–eye peas: 180mg
Lentils: 148mg
Split peas: 148mg
Lima beans: 142mg
Kidney beans: 132mg
Black beans: 130mg
Almonds: 46.4mg
Peanuts: 42.4mg
Chestnuts: 42.4mg
Cashews: 38mg
Yogurt: 11.3mg
cooked egg: 9mg
Green soybeans: 12.8mg
Cottage cheese: 10.4mg
Milk: 4.9mg
Fresh tomatoes: 9mg
Veal liver: 8.9mg per 3.5 oz–serving
The recommended dietary allowance (RDA) for
molybdenum was most recently revised in January 2001:
Infants: (0–6 months): 2mg.
Infants: (7–12 months): 3mg.
Children (1–3 y): 17mgMolybdenumRecommended Dietary
Age Allowance (mcg)
Children 0–6 mos. 2
Children 7–12 mos. 3
Children 1–3 yrs. 17
Children 4–8 yrs. 22
Children 9–13 yrs. 34
Adolescents 14–18 yrs. 43
Adults 19 yrs. 45
Pregnant women 50
Breastfeeding women 50
Molybdenum
Food (mcg)
Beans, navy, 1 cup 196
Black-eye peas, 1 cup 180
Lentils, 1 cup 148
Split peas, 1 cup 148
Beans, lima, 1 cup 142
Beans, kidney, 1 cup 132
Beans, black, 1 cup 130
Almonds, 1 cup 46.4
Chestnuts, 1 cup 42.4
Peanuts, 1 cup 42.4
Cashews, 1 cup 38
Soybeans, green, 1 cup 12.8
Yogurt, 1 cup 11.3
Cottage cheese, 1 cup 10.4
Egg, cooked, 1 cup 9
Tomatoes, fresh, 1 cup 9
Veal liver, 3.5 oz. 8.9
Milk, 1 cup 4.9
mcgmicrogram(Illustration by GGS Information Services/Thomson Gale.)
Molybdenum