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Alleviating aluminum toxicity

In addition, flavonoids fulfill crucial functions, such In the A4P5 vs. A4P_ comparison groups, under the
as enhancing plant resistance and adaptability in same Al stress conditions, 19 differentially abundant
response to environmental pressures, and play a vital metabolites were detected in high levels without
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role in plant defense mechanisms. Flavonoids can be P treatment; after P treatment, 35 differentially abundant
used as natural antifungal agents or plant antitoxins, metabolites were detected in high levels. Among the
helping plants resist external damage. In addition, the differentially abundant metabolites, in the absence of
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accumulation of flavonoids in plant roots can modify P, the metabolites with the highest levels were clitorin,
root structure, potentially helping to dissolve insoluble kaempferol-3-O-rutinoside-7-O-rhamnoside, and
P in the soil to increase its availability. In this study, quercetin-3-O-arabinoside. After P treatment, the eight
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the changes in flavonoid metabolites across different differentially abundant metabolites with the highest levels
treatment groups may serve as important indicators of were violanthin, tararixetin-3-O-(6’’-malonyl)glucoside,
C. oleifera seedlings’ response to P and Al stress. kaempferol-3-O-neohesperidoside-7-O-glucoside,
The screening results for the differentially abundant kaempferol-3-O-rutinoside-7-O-glucoside, luteolin-7-
metabolites revealed that many metabolites were O-neohesperidoside, luteolin-7-O-rutinoside, biondnoid
significantly different in the comparison groups. I, and quercetin-3-O-(4’’-O-glucosyl)rhamnoside. In
For example, 179 metabolites exhibited substantial the A4P5 vs. A4P_ comparison group, under the same
disparities when comparing A4P5 and A4P_ treatment Al stress conditions, the addition of P increased the
groups, and in the comparison between the A4P5 and A_ number of differentially abundant metabolites from
P5 treatment groups, 171 metabolites manifested notable 19 to 35. These increased metabolites may play a role in
discrepancies. In addition, 153 metabolites showed antioxidation, thereby reducing oxidative damage caused
pronounced differences between the A_P5 and A4P_ by Al stress and helping plants adapt to it.
treatment groups. In the A4P5 vs. A_P5 comparison Moreover, across the three comparison groups,
group, under the same P conditions, 40 differentially 35 metabolites of common differential abundance status
abundant metabolites were detected in high levels after were detected, and each comparison group harbored its
Al treatment; in the absence of Al treatment, only nine own distinctive metabolite profiles. Some researchers
differentially abundant metabolites were detected in high have studied the effects of long-term interactions of Al
levels. Among the metabolites showing differences in and P on the concentration and release of malate and
abundance, myricetin-3,7,3’-trimethyl ether was the most citrate in citrus roots, and the results show that malate
abundant differentially abundant metabolite in the absence and citrate are mainly released from the root surface.
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of Al. After Al treatment, there were 13 differentially In the current study, the content of flavonoid metabolites
abundant metabolites detected, including petunidin- in C. oleifera increased under P and Al stress, which
3-O-(6’’-O-p-coumaroyl)rutinoside, homoeriodictyol may represent a coordinated response to the interaction
7-O-glucoside, tamarixetin-3-O-(6’’-malonyl)glucoside, between P and Al. In addition, plants can regulate
gambiriin B1, luteolin-6-C-glucoside-7-O-rhamnoside, root morphology by removing P from phosphorylated
pellamurin, hesperetin-5-O-glucoside, quercetin-4’-O- metabolites, thereby promoting the accumulation of
glucoside, quercetin-7-O-glucoside, kaempferol-3-O- flavonoids to address P deficiency. The existence of these
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sulfonate, quercetin-3-O-(4’’-O-glucosyl)rhamnoside, differentially abundant metabolites reflects the metabolic
1,8-dihydroxy-4,5-dimethoxy-3-([{2s,3r,4s,5s,6r}- adjustment of plants under different stress conditions. The
3,4,5-trihydroxy-6-{hydroxymethyl}oxan-2-yl] analysis of commonly differentially abundant metabolites
oxy)xanthen-9-one, and dehydroepigallocatechin (such as mangiferin, diosmetin, and gnetifolin B) and
6-C-Glucoside-3’-C-arabinoside. In the A4P5 vs. A_P5 unique differentially abundant metabolites provides
comparison groups, under the same P conditions, the evidence for the specific responses of plants to distinct
number of differentially abundant metabolites increased stress conditions. For example, commonly differentially
from 9 to 40 after Al treatment. These differentially abundant metabolites may be associated with the
abundant metabolites may be involved in the process underlying defense mechanisms of plants. 43
of Al detoxification. Previous studies have shown that The KEGG functional annotation and enrichment
quercetin is secreted from the roots of plants under Al analysis of differentially abundant metabolites
stress and forms a stable, non-toxic complex by binding showed that the isoflavone biosynthesis pathway
to Al ions, thereby reducing the toxicity of Al to plants. was significantly enriched. This result is consistent
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This complex plays a key role in Al stress and has with previous research indicating that isoflavones are
important value in the mechanism of stress resistance. crucial in enhancing plants’ stress tolerance. A higher
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Volume 22 Issue 5 (2025) 175 doi: 10.366922/AJWEP025150108