The complexation of ferric ion with fulvic acid and hydroxamates

OXYGEN

281

DO14 THE COMPLEXATION OF FERRIC ION WITH FULVIC ACID AND HYDROXAMATES Shouheng * Dept.

Zhu * ,Yifang Soil Sci.

Zhao + ,Xianxuan

Plant Nutrn. Beijing

University,Beijing,100094 Beijing The

Medical

University,

complexation

drolytic

,China;

organisms. In this studied as iron (III)

with those

titration

in Fe (III)

ly, but only a metastable

system

are all shifted

systems,

to evaluate

It coordinates citrate

complexes

A cyclic hydroxamic

4-benzoxaine-3-one solution

polarizibility.

(DMBO)

with citrate

apotransferrin.

systems (>

iron from citrate

results

complex

com-

2; 3. 5 -

A series of synthetic

their

ability

hy-

to inhibit

in presence

hy-

of citrate

as .

idlcii-

Among the hydroxamates

studied,

In the Fe -citrate-hydroxamates

were

characterized

spectropho-

acid, Z , &dihydroxy-7-methoxy-l ,

from corn seedling is a better by complexing

were also studied The

side,

of ferric ions significant-

and stabilize

in a broad pH range. Th DMBO-Fe<1111 systems

9. 7 >

0; pdyrmrizaiiod

acid is most effective.

ternary

to alkaline

and Fe (III)-PO, the hydrolysis

drolytic polymerization of Fe(III) , especially ..l_ ., *_... - ligand, as rev”” L ic: ~LLlAld&y dci: 1:, it;ij degree

tometrically.

hy-

in iron uptake by

(5. 6 - 9. 5; 5. l-

sol was produced.

acids were studied

acethydoxamic

mean to prevent

work fulvic acid (FA> and hydroxamates were ligands The pH ranges of hydrolytic precipitation

of FA inhibits

lated from magnetic

Sci. ,

100083 ,China.

and Fe (III)-FA-PO,

10. 4). Excess droxamic

Beijing,

Chen t *

of Pharm.

of Fe(III) , which is important

given by potentiometric paring

* * School

of iron (III > is an effective

precipitation

in Fe (III)-FA

Chen * * ,Yue

Agricultural

DMBO

to apotransferrin.

the iron(III)

and DMBO-Fe

as iron donors

show that

inhibitor.

transfering

faciliates

(III)iron to

the transfer