J Appl Ichthyol. 2017;1–5. wileyonlinelibrary.com/journal/jai
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1 © 2017 Blackwell Verlag GmbH
Received: 5 June 2016
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Accepted: 29 November 2016
DOI: 10.1111/jai.13356
ORIGINAL ARTICLE
Fatty acid profiles of Trachinus radiatus Cuvier, 1829
(Perciformes-Trachinoidei, Trachinidae)
D. Đikić
1
| I. Landeka
2
| D. Franjević
1
| D. Skaramuca
1
| R. Fuchs
3
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S. Matić Skoko
4
| P. Tutman
4
| I. Lukić
1
| B. Skaramuca
5
1
Department of Animal Physiology, Faculty of
Science University of Zagreb, Zagreb, Croatia
2
Faculty of Food Technology and
Biotechnology, Zagreb, Croatia
3
Institute of Medical Research, Zageb, Croatia
4
Institute of Oceanographic Research, Split,
Croatia
5
University of Dubrovnik, Dubrovnik, Croatia
Correspondence
Domagoj Đikić, Faculty of Science,
Department of Animal Physiology, University
of Zagreb, Zagreb, Croatia.
Emails: magistar_djikic1@yahoo.com;
domagoj.djikic@biol.pmf.hr
Funding information
Ministry of Science, Education and Sports of
the Republic of Croatia
Summary
The goal of this study was to analyse the fatty acid (FA) profiles of the streaked (starry)
weever (Trachinus radiatus), a prized food fish in the countries of its distribution. Fish
(N = 20) were sampled in July 2011. Location: 42.761019°N, 17.765090°W; Adriatic
Sea, Elaphite Islands near Dubrovnik, Croatia, at 5–10 m depth using longline hooks;
body length ranges: 24.1–47.2 cm, weight ranges: 120–960 g. Morphological species
determination was genetically confirmed (Folmer region of COI gene). Biochemical
analysis of T. radiatus muscular tissue (filet) revealed average ± SD dry matter of
252.3 ± 14.8 g/kg w.w.; moisture of 747.7 ± 14.8 g/kg w.w., and ash of 28.0 ± 6.9 g/
kg w.w. Intramuscular crude protein content exceeded the total lipid (TL = 11.9 ± 4.0 g/
kg w.w.) content approximately 17.7 fold. Unsaturated FA (UFA) was higher than satu-
rated FA (SFA), with a predominance of polyunsaturated FA (PUFA). The ω3:ω6 ratio
was 4.9:1, respectively. Among individually determined fatty acids, the PUFA 22:6n3
(DHA) was highly present (29.99 ± 2.75% TL) followed by a relatively high 20:5n3
(EPA) content. There was 25 fold higher EPA content than of substrate αLNA, and a
15.5 fold higher DHA content to DPAn3. Such ratios indicate that besides trophic
ingestion, FA bioconversion elongase/desaturase synthesis pathways toward ω3
PUFA in Weevers could be highly efficient.
1 | INTRODUCTION
Fish are a frequent source of unsaturated fatty acids in human nutri-
tion while accumulating these acids via the marine food web (Teparić,
Landeka, Tomić, & Đikić, 2012; Tillander etal., 2014). Fatty acid pro-
files are frequently studied in many species (Betancor, Olsen, Solstorm,
Skulstad, &Tocher, 2016; Li et al., 2015; Liang, Zhao, Li, & Gao, 2016;
Murray, Hager, Tocher, & Kainz, 2015).
The lipid profile of species of the whole family of weevers is rarely
studied and there are no published data whatsoever regarding the
Trachinus radiatus fatty acid composition. The species is widely dis-
tributed in the Mediterranean Sea and eastern Atlantic Ocean, from
Gibraltar to Angola (Jardas, 1996). Limited literature on the biology
of T. radiatus in Mediterranean waters is evident, although the spe-
cies is prized and consumed in the countries near its distribution. It
reaches a maximum total length of 50.0 cm (Fischer, Schneider, &
Bauchot, 1987). Little is known about the reproduction, except that it
is oviparous with pelagic eggs and larvae and an early winter spawning
period, at least in the Adriatic Sea population (Jardas, 1996). Weevers
are known to possess a venomous spike (Barceloux, 2008). The wee-
vers are not specifically protected by legislation or by management
(Carpenter, Smith-Vaniz, Bruyne, & de Morais, 2015).
The objective of this study was to identify the intramuscular total
lipid composition and fatty acid profiles in the streaked (starry) weever
(Trachinus radiatus Cuvier, 1829), to explore whether this species is a
promising source of essential fatty acids.
2 | MATERIALS AND METHODS
2.1 | Experimental animals
Weever (Trachinus radiatus) specimens (N = 20) were collected the
same month (09 and 29 July 2011) and at the same location in the
Adriatic Sea, to ensure that all analysed fish were sampled under