ABSTRACT
The thermal and oxidative stability of Atlantic salmon oil (Salmo salar L.) as well as its ß-cyclodextrin (ß-CD) complexation ability has been verified for the first time. The main omega-3 fatty acids, EPA and DHA, were significantly degraded, even at 50 °C. Their relative concentrations decrease from 6.1% for EPA and 4.1% for DHA to 1.7% and 1.5% after degradation at 150 °C, respectively. On the other hand, the relative concentrations of monounsaturated and saturated fatty acids remained constant or slightly increased by a few percent after degradation (e.g., from 10.7% to 12.9% for palmitic acid). Co-crystallization of ASO with ß-CD at a host-guest ratio of 1:1 and 3:1 from an ethanol-water mixture and kneading methods has been used for the preparation of ß-CD/ASO complexes. The analysis of the complexes by thermogravimetry, differential scanning calorimetry (DSC), and Karl Fischer titration (KFT) as well as the decrease of the "strongly-retained" water content confirm the formation of the inclusion compound. Furthermore, the DSC parameters correlate well with the KFT kinetic data for ß-CD/ASO complexes.
ABSTRACT
AIMS: Free radicals may not only affect the denatured cell structure but also reduce protein levels. These mechanisms are critical and need to be clarified as a high priority. Because of the limited information on this subject, in this respect, the effects on protein levels of liver tissue in rats fed hot-smoked rainbow trout (Oncorhynchus mykiss) were investigated. METHODS: Four diets containing fresh and hot-smoked rainbow trout flesh and vitamins were prepared and commercial pellet food was purchased. Four groups of female Wistar rats were fed the diets for 28 days. The rats were killed by decapitation, and the hepatic tissue was removed. Total protein and detection of protein bands using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) were evaluated. RESULTS: The liver protein level in rats fed a hot-smoked rainbow trout flesh + vitamin diet was increased significantly compared with the other diet groups (p < 0.001, p < 0.009 and p < 0.011). 10 protein bands were visualized on rat gels. The molecular weights of protein bands detected were 200, 130, 70, 50, 42, 38, 26, 25, 24 and 14 kDa, respectively. The 25-kDa band of group V had a dense appearance. Also, the 14-kDa band appeared as very dense in groups V, B and K, but this band did not have a dense appearance in group D. CONCLUSION: Nourishment with smoked fish diets containing antioxidant substances reduced the harmful effects of free radicals and positive effects were observed on protein metabolism.
