Abstract
Excess SO42- in solution has been demonstrated to reduce aluminum (Al) toxicity in several studies, but the mechanism of SO42--induced reduction of Al toxicity was not clearly understood. In this study, Size Exclusion Chromatography (SEC; Sephadex G-25, superfine resin) was employed to investigate the interaction between Al and SO42- in unhydrolyzed Al solutions at pH 3.5. A dual peak elution of Al was observed when Al solution with SO4/Al molar ratio ≥ 2.0 was injected into the SEC column. The first Al peak, which was eluted substantially earlier than the bed volume of the column, where the monomeric Al species are expected, was due to co-elution of Al with SO42- as evident from the position of this peak corresponding to the elution volume for peak elution of SO42-. The elution fraction at the first Al peak contained SO42- and Al at a SO4/Al molar ratio = 2.7. The co-elution of Al and SO42- would appear to be due to outer sphere SO42- complexation which has been referred to as “SO42-complexed Al‘’ in this paper. The Al peak for co-elution of Al and SO42- increased, while the peak at the bed volume decreased with an increase in SO4/Al molar ratio of the injected sample. A nutrient-solution experiment was conducted to evaluate the differential toxicity of SO42--complexed Al (eluted by the SEC column), and monomeric Al in the absence of SO42- [as Al(NO3)3] in the range of 0 to 40 μM total applied Al concentrations. The SO42- complexed Al was less phytotoxic to soybean (Glycine max L.) root growth than the monomeric Al. The shielding effect of SO42- in the outer sphere of Al would appear to be responsible for the reduction in Al toxicity.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 7
Claim · model-written summary
Aluminum and sulfate co-eluted in size exclusion chromatography when the injected solution had a sulfate to aluminum molar ratio of at least 2.0.
Not reportedTaxon
Verbatim
e0“A dual peak elution of Al was observed when Al solution with SO4/Al molar ratio ≥ 2.0 was injected into the SEC column.”
Claim · model-written summary
The first aluminum peak contained sulfate and aluminum at a molar ratio of 2.7.
Not reportedTaxon
Verbatim
e0“The elution fraction at the first Al peak contained SO42- and Al at a SO4/Al molar ratio = 2.7.”
Claim · model-written summary
The co-elution of aluminum and sulfate was interpreted as outer sphere sulfate complexation.
Not reportedTaxon
Verbatim
e0“The co-elution of Al and SO42- would appear to be due to outer sphere SO42- complexation”
Claim · model-written summary
As the sulfate to aluminum ratio increased, the co-elution aluminum peak increased.
- Treatment
- increase in SO4/Al molar ratioe0
- Outcome
- Al peak for co-elution of Al and SO42-e0
- Direction
- increasede0
Not reportedTaxon
Verbatim
e0“The Al peak for co-elution of Al and SO42- increased, while the peak at the bed volume decreased with an increase in SO4/Al molar ratio of the injected sample.”
Claim · model-written summary
As the sulfate to aluminum ratio increased, the aluminum peak at bed volume decreased.
Not reportedTaxon
Verbatim
e0“The Al peak for co-elution of Al and SO42- increased, while the peak at the bed volume decreased with an increase in SO4/Al molar ratio of the injected sample.”
Claim · model-written summary
Sulfate-complexed aluminum was less toxic to soybean root growth than monomeric aluminum.
- Taxon
- soybean
Glycine maxe0 - Treatment
- SO42- complexed Ale0
- Outcome
- root growthe0
- Direction
- less phytotoxice0
- Comparator
- monomeric Ale0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The SO42- complexed Al was less phytotoxic to soybean (Glycine max L.) root growth than the monomeric Al.”
Claim · model-written summary
The authors attributed reduced aluminum toxicity to sulfate shielding in its outer sphere.
- Taxon
- PLANTSViridiplantaet0
- Outcome
- reduction in Al toxicitye0
- Qualifier
- shielding effect of SO42- in the outer sphere of Ale0
Verbatim
e0“The shielding effect of SO42- in the outer sphere of Al would appear to be responsible for the reduction in Al toxicity.”
t0“TO PLANTS”
The same questions in other papers
aluminium atom · growth · Glycine max (soybean)Results differ
15 papers in the same direction as this paper · 28 in the opposite direction
- negative
- negative
- no effect
40 papers more in this group
See all 44 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.