Lipid composition and antioxidant activity of liver oils from ray species living in Tunisian coasts

Abstract

The proximate composition, fatty acid profiles, physicochemical properties and radical scavenging activities of liver oil from three ray species, Dasyatis pastinaca, Dasyatis violacea and Rhinoptera marginata, were investigated. Lipid contents of D. pastinaca (58.27%) and D. violacea (57.33%) were significantly high compared to those of R. marginata (10.90%). Among minerals, K and Na were the most abundant elements and the highest values were observed for R. marginata (153.7 and 115.86 mg/100 g, respectively). The fatty acid profiles exhibited a dominance of unsaturated fatty acids exceeding 65% of the total fatty acids. C16:0, C18:0 and C14:0 were the major saturated fatty acids. The most abundant monounsaturated fatty acids were C18:1 (10.88-21.98%) and C16:1 (4.47-23.95%). Interestingly, omega-3 polyunsaturated fatty acid profiles exhibited a dominance of eicosapentaenoic acid (3.36-5.51%) and docosahexaenoic acid (9.07-30.50%). D. pastinaca contained the highest carotenoid and total phenolic content accompanied with the strongest free radical scavenging abilities. This study suggests that ray livers which were actually wasted, could be used as new raw material for omega-3 polyunsaturated fatty acid oil production and a good source of carotenoids and phenolic compounds.

Nutritional properties, oxidative stability, and in vitro digestibility of oils extracted from muscles of wild and breeding eels (Anguilla anguilla)

“…Among the saturated FAs (SFAs), those occurring at the highest proportions were Palmitic acid (C 16:0 , ranging from 19.74 to 21.35%) followed by stearic acid (C 18:0 , ranging from 3.73 to 4.46%) (Table ). Similar SFA values were reported by Sellami et al () for ray liver oils. In the present study, total SFA content in wild A. anguilla oil (38.41%) was higher than that of breeding eel oil (31.1%) (Table ).…”

“…The density of the oils extracted from eel muscles ranges from 1.10 to 1.17. Similar values were reported for stingray oil (Sellami et al, ). Ii of wild eel oil (Ii = 387.04 g I 2 /100 g) was significantly higher than that of the breeding one (215.73 g I 2 /100 g).…”

“…Similar studies reported the effective role of DHA in preventing skin disorders and in brain development (Ziboh, Miller, & Cho, ). The EPA content is similar to those of other fish oils (Sellami et al, ; Smichi et al, ). ω‐6 PUFAs contents were 3.75 and 7.77% for breeding and wild A. anguilla , respectively.…”

“…The most abundant monounsaturated FAs (MUFAs) found in both oil samples were oleic acid (C 18:1 , contents ranging from 34.29 to 40.21%) and palmitoleic acid (C 16:1 , contents ranging from 8.96 to 11.37%). Oleic acid contents in both eel oils are significantly higher than values reported for sharks liver oils (Nichols, Bakes, & Elliott, ) and rays ( Dasyatis brevis , Gymnura marmorata , and Dasyatis pastinaca ) (Navarro‐Garcia et al, ; Sellami et al, ). The percentages of PUFAs found in eel oils were comparable (Table ).…”

“…Indeed, these PUFAs are nowadays recognized for their important role in the prevention and treatment of hypertension, coronary heart diseases, arthritis, asthma, psoriasis and other inflammatory and autoimmune disorders (Calder, ; Fernandes et al, ; Khawaja et al, ; Serhan, ). For these reasons, PUFAs are widely used in human food, cosmetics, nutraceutics and pharmaceutical fields (Sellami, Ben Rebah, Gargouri, & Miled, ).…”