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MANFRED ANKE AN. R. ACAD. NAC. FARM.

TABLE 16. Vanadium balance of non-nursing and nursing women with mixed diet

Parameter (n) Non-nursing Nursing p%
sx xs

Intake, µg/day (49;49) 13 7.9 12.1 14.0 > 0.05 153

Excretion Faeces, µg/d (49;49) 6.8 7.2 15.6 19.1 > 0.05 217
Excretion Urine, µg/d (49;49) 1.4 0.7 0.8 1.0 > 0.05 114

Excretion Milk, µg/d (0;7) – 3.4 2.9

Excretion Faeces, % 91 79
Excretion Urine, % 94
Excretion Milk, % – 17

Apparent absorption rate, % 8.9 –

Balance µg/day ± 0.0 – 7.7
% ± 0.0 – 64

The Essentiality of Vanadium

Essentiality to Plants

The evidence that vanadium is essential for the growth of higher
plants is not yet conclusive, while the essentiality of this element for
algal species is unquestionable. Vanadium is essential for several
species of green algae (Scenedesmus obliquus, Chlorella pyrenoida-
sa), yellow-green algae (Bumileriquisis filiformia) and brown algae
(Fucus spiralis). A very low concentration (0.1-1 µg V/L) of vana-
dium induces growth. At higher concentrations, growth is still sti-
mulated, but chlorophyll formation even more.

In the brown alga Ascophyllum nodosum, the activity of the
enzyme bromoperoxidase is essentially influenced by vanadium (21,
128, 35). By means of vanadate, the inactive apoenzyme can be re-
constituted to active holoenzyme. Vanadium is an essential element
for algae and probably for other organisms. The reactivation of
apoperoxidase by vanadium is inhibited by phosphate. Since vana-
dium-dependent bromoperoxidases have been found in a number of

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