Selenium speciation profiles in biofortified sangiovese wine.

Area of Science:

• Agronomy
• Plant Science
• Food Science

Background:

• Biofortification using selenium (Se) is a key strategy to combat dietary Se deficiencies in vulnerable populations.
• Foliar application of Se offers efficient plant assimilation, bypassing root-to-shoot translocation limitations.

Purpose of the Study:

• To evaluate the efficacy of foliar selenium (Se) application on Sangiovese grapevines.
• To quantify Se accumulation in grapevine leaves, grapes, and wine.
• To analyze the chemical forms of Se in the resulting wine.

Main Methods:

• Sangiovese grapevines were treated with sodium selenate (100mg Se L⁻¹) during the pre-flowering stage.
• Selenium concentrations in leaves, grapes, and wine were determined using Inductively Coupled Plasma Mass Spectrometry (ICP-MS).
• The chemical speciation of Se in wine was analyzed to differentiate inorganic and organic forms.

Main Results:

• Treated leaves showed significantly higher Se content (16.0±3.1mgkg⁻¹ dw) compared to controls (0.17±0.006mgkg⁻¹ dw).
• Se-enriched grapes contained 0.800±0.08mgkg⁻¹ dw, a substantial increase from control grapes (0.065±0.025mgkg⁻¹ dw).
• Wine from treated vines had 0.620±0.09mg Se L⁻¹, compared to 0.024±0.010mg Se L⁻¹ in control wine, with a higher proportion of inorganic Se(VI).

Conclusions:

• Foliar application of sodium selenate effectively increases Se content in grapevines, grapes, and wine.
• The enrichment process altered the Se speciation in wine, increasing the inorganic fraction, predominantly Se(VI).
• Further research should focus on optimizing Se application strategies to achieve a balanced distribution of Se species, potentially favoring organic forms for enhanced nutritional benefits.