How To Stabilize ω‑3 Polyunsaturated Fatty Acids (PUFAs) in an Animal
Feeding Study?Effects of the Temperature, Oxygen Level, and
Antioxidant on Oxidative Stability of ω‑3 PUFAs in a
Mouse Diet
posted on 2020-03-23, 15:44authored byJianan Zhang, Michael A. Freund, Mitchell D. Culler, Ran Yang, Phoebe B. Chen, Yeonhwa Park, Eric A. Decker, Guodong Zhang
Substantial studies
have shown that ω-3 polyunsaturated fatty acids (PUFAs) have
various health-promoting effects; however, there are inconsistent
results from animal studies that showed that ω-3 PUFAs have
no effects or even detrimental effects. Emerging research suggests
that oxidized ω-3 PUFAs have different effects compared to unoxidized
ω-3 PUFAs; therefore, lipid oxidation of dietary ω-3 PUFAs
could contribute to the mixed results of ω-3 PUFAs in animal
studies. Here, we prepared an AIN-93G-based, semi-purified, powder
diet, which is one of the most commonly used rodent diets in animal
studies, to study the oxidative stability of fortified ω-3 PUFAs
in animal feed. We found that lowering the storage temperature or
the addition of a certain antioxidant, notably tert-butylhydroquinone (TBHQ), helps to stabilize ω-3 PUFAs and
suppress ω-3 oxidation in the animal diet, while reducing the
level of oxygen in the storage atmosphere is not very effective. The
addition of 50 ppm of TBHQ in the diet inhibited 99.5 ± 0.1%
formation of primary oxidation products and inhibited 96.1 ±
0.7% formation of secondary oxidation products, after 10 days of storage
of the prepared diet at a typical animal-feeding experiment condition.
Overall, our results highlight that ω-3 PUFAs are highly prone
to lipid oxidation in a typical animal-feeding experiment, emphasizing
the critical importance to stabilize ω-3 PUFAs in animal studies.