Determination of organic selenium compounds in Kratošija wine applying HPLC-ESI-MS/MS

Organic selenium compounds, specifically selenomethionine (SeMet) and Semethylselenocysteine

(MeSeCys) are the major selenium-containing amino acids in dietary
sources. SeMet is a bioactive form of selenium with antioxidant properties, playing a significant
role in cardiovascular health, autoimmune conditions, and the prevention of certain cancers,
while Se-methylselenocysteine is a naturally occurring organoselenium compound found in
certain plants and is known for its high peroral bioavailability in humans. Selenomethionine oxide
(SeMetO) is the oxidized form of the amino acid selenomethionine and possesses a protective
mechanism against oxidative stress. In this study, SeMet, SeMetO and MeSeCys were determined
in Kratošija wines by applying a rapid and sensitive HPLC-ESI-MS/MS technique. The HPLC
method was optimized and validated through the determination of slope, R
(correlation
coefficient), LOD (limit of detection) and LOQ (limit of quantification). Wines were produced by
inoculating two commercial Saccharomyces cerevisiae yeasts: Zymaflore
Xpure (Laffort) and
Lalvin ICV D80 (Lallemand) in order to study the effect of yeasts on the selenium compounds
content in the final wines. It was observed that wine fermented with Lalvin ICV D80 contained
higher amounts of SeMet and MeSeCys, probably due to a better ability of the yeast to transform
the inorganic selenium into organic selenium compounds (especially selenomethionine). Both
wines contained high levels of SeMetO, produced as a result of the oxidation of SeMet during wine
fermentation and/or storage. The results obtained are preliminary and provide a basis for future
studies using various varieties and vinification processes.