Effects of Eco-friendly Squid Todarodes pacificus Liver and Patagonian Toothfish Dissostichus eleginoides Muscle Oils on the Serum Lipids and Adipose Tissues of Rats

This study investigated the effects of squid Todarodes pacificus liver oil on the serum lipids and adipose tissue weight of rats. The rats in the soybean oil (SO) group received a basic diet prepared according to the recommendations of the American Institute of Nutrition (AIN-93G), with 7% SO as lipid source. The rats in the Patagonian toothfish Dissostichus eleginoides muscle oil (PTFO) group received 5% PTFO and 2% SO as the lipid source, while the rats in the eco-friendly squid liver oil (EFSO) group received 5% EFSO and 2% SO. EFSO was prepared according to the method outlined in the author’s patent. PTFO was extracted from muscle using a physical method in the author’s laboratory. The prominent polyunsaturated fatty acids in the dietary oils were 18:2n-6 (54.3%) and 18:3n-3 (5.64%) in SO, DHA (6.77%) and EPA (3.61%) in PTFO, and DHA (26.2%) and EPA (9.94%) in EFSO. After feeding for 4 weeks, the serum lipid levels (e.g., triglyceride, total cholesterol, and low-density lipoprotein cholesterol) of the rats in the EFSO group were significantly reduced as compared with those in the SO group (P<0.05); those of the rats in the PTFO group were also reduced, albeit not significantly, compared with the SO group. On the other hand, the total white adipose tissue (visceral, epididymal, and perirenal) weight was significantly reduced in the EFSO and PTFO groups compared to the SO group. These results demonstrate that EFSO is an effective lipid modifying agent in rat blood, and that EFSO and PTFO have greater anti-obesity effects than SO.