Red Meat Derived Glycan, N-acetylneuraminic Acid (Neu5Ac) Is a Major Sialic Acid in Different Skeletal Muscles and Organs of Nine Animal Species-A Guideline for Human Consumers

Marefa Jahan; Peter C Thomson; Peter C Wynn; Bing Wang

doi:10.3390/foods12020337

Red Meat Derived Glycan, N-acetylneuraminic Acid (Neu5Ac) Is a Major Sialic Acid in Different Skeletal Muscles and Organs of Nine Animal Species-A Guideline for Human Consumers

Foods. 2023 Jan 10;12(2):337. doi: 10.3390/foods12020337.

Authors

Marefa Jahan¹, Peter C Thomson², Peter C Wynn^{1

3}, Bing Wang^{1

3}

Affiliations

¹ School of Agricultural, Environmental and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia.
² School of Life and Environmental Sciences, University of Sydney, Camden, NSW 2750, Australia.
³ Gulbali Institute for Agriculture, Water and Environment, Charles Sturt University, Wagga Wagga, NSW 2678, Australia.

Abstract

Sialic acids (Sias) are acidic monosaccharides and red meat is a notable dietary source of Sia for humans. Among the Sias, N-acetylneuraminic acid (Neu5Ac) and 2-keto-3-deoxy-D-glycero-D-galacto-2-nonulosonic acid (KDN) play multiple roles in immunity and brain cognition. On the other hand, N-glycolylneuraminic acid (Neu5Gc) is a non-human Sia capable of potentiating cancer and inflammation in the human body. However, their expression within the animal kingdom remains unknown. We determined Neu5Ac and KDN in skeletal muscle and organs across a range (n = 9) of species using UHPLC and found that (1) caprine skeletal muscle expressed the highest Neu5Ac (661.82 ± 187.96 µg/g protein) following by sheep, pig, dog, deer, cat, horse, kangaroo and cattle; (2) Among organs, kidney contained the most Neu5Ac (1992−3050 µg/g protein) across species; (3) ~75−98% of total Neu5Ac was conjugated, except for in dog and cat muscle (54−58%); (4) <1% of total Sia was KDN, in which ~60−100% was unconjugated, with the exception of sheep liver and goat muscle (~12−25%); (5) Neu5Ac was the major Sia in almost all tested organs. This study guides consumers to the safest red meat relating to Neu5Ac and Neu5Gc content, though the dog and cat meat are not conventional red meat globally.

Keywords: N-acetylneuraminic acid (Neu5Ac); animal species; ketodeoxynonulosonic acid (KDN); muscle and organ tissue; sialic acid.

Grants and funding

This research received no external funding.