Figure 2:  The organic and inorganic Se content compared to the total Se (%) of various fresh commercial Se-yeast (SY) products 

The recent advances in analytical methodologies have led to an increasingly more accurate, reliable, and comprehensive determination of the composition of seleno-yeasts. These analyses reveal the presence of inorganic Seo, which explains a large part of the previously unknown Se species. These analytical improvements have allowed us to measure an additional inorganic Se form, that is, Elemental Se (Seo ), previously uncharacterized in products. When applied to seleno-yeasts, it better differentiates inorganic and organic selenium and therefore, Seo should now be taken into account to obtain a precise evaluation of the variable composition of seleno-yeasts. New questions could also arise related to the categorization of these Se forms and their nutritional significance.

These findings demonstrate that the seleno-yeast products used in animal nutrition contain far less than 97% of total Se as organic Se. Thus, the proportion of inorganic Se in seleno-yeast products should be revised and, consequently, a complete characterization of inorganic Se species should also be performed. According to these findings, the characterization of seleno-yeasts as a full organic form of Se can now be questioned and, consequently, the end users and the industry will now have the opportunity to make a more thoughtful choice when it comes to deciding how much to invest in an organic Se form.

Read the full study:

Is There More Inorganic Selenium In Seleno-Yeasts Than Previously Believed?
Article Published In All About Feed | VOLUME 30, NO. 2, 2022


Mohammed Amine HACHEMI, DMV
R&D Project Manager in Animal Nutrition at Adisseo

Mickaël BRIENS, PhD
R&D Manager Antioxidant Solutions at Adisseo

Michele DE MARCO, PhD
Global Category Manager Antioxidants Solutions at Adisseo


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