Environmental constraints on the lipid composition and metabolism of euphausiids: the case of Euphausia superba and Meganyctiphanes norvegica

2000 ◽  
Vol 57 (S3) ◽  
pp. 91-103 ◽  
Author(s):  
P Mayzaud ◽  
E Albessard ◽  
P Virtue ◽  
M Boutoute

Antarctic (Euphausia superba) and northern krill (Meganyctiphanes norvegica) are characterised by large-scale spatial distributions. Euphausia superba is limited to the Southern Ocean, while M. norvegica is present from the Arctic Ocean to the Mediterranean Sea. Euphausia superba structural lipids showed little mesoscale variability. Specific differences between phosphatidylcholine and phosphatidylethanolamine fatty acid composition exceeded variability related to sampling stations. On a larger scale (Southern Ocean), fatty acid composition of both total polar lipids and phosphatidylcholine confirmed the reduced level of regional variability. Similar comparisons between female M. norvegica collected at two extreme sites in terms of temperature regime (Kattegat and Ligurian Sea) during two seasons (spring-summer and fall-winter) suggested a more complex picture. Levels of phosphatidylethanolamine, lysophosphatidylcholine, and diphosphatidylglycerol showed significant differences between sites. During spring- summer, a lower content of phosphatidylethanolamine and lysophosphatidylcholine was observed for the Ligurian Sea population. Fatty acid composition of total polar lipids was significantly different at both sites. Comparisons between spring-summer populations at both sites showed higher percentages of 22:6n-3 and a lower content in saturated and monoenoic acids for the Ligurian Sea, suggesting some degree of adaptation to temperature regime.

Foods ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 171 ◽  
Author(s):  
Ronan Lordan ◽  
Eoin O’Keeffe ◽  
Alexandros Tsoupras ◽  
Ioannis Zabetakis

The in vitro antithrombotic properties of polar lipid constituents of malted grain (MG), pelleted hops (PH), brewer’s spent grain (BSG), spent hops (SH), wort, and bottled beer from the same production line were assessed in human platelets. The total lipids (TL) were extracted according to the Bligh and Dyer method and further separated into the total neutral lipids (TNL) and total polar lipids (TPL) extracts by counter-current distribution. The TL, TNL, and TPL extracts of all samples were assessed for their ability to inhibit platelet-activating factor (PAF) and thrombin-induced human platelet aggregation. The raw materials, by-products, wort, and beer lipid extracts all exhibited antithrombotic properties against PAF and thrombin. However, the beer TPL exhibited the lowest IC50 values against PAF-induced (7.8 ± 3.9 µg) and thrombin-induced (4.3 ± 3.0 µg) platelet aggregation indicating that these polar lipids were the most antithrombotic. The lipid extracts tended to be more bioactive against the thrombin pathway. The fatty acid content of all the TPL extracts were assessed using GC-MS. The fatty acid composition of the most bioactive TPL extracts, the wort and the beer, shared similar fatty acid profiles. Indeed, it was noted that fermentation seems to play a role in increasing the antithrombotic properties of polar lipids against PAF and thrombin by moderately altering the polar lipid fatty acid composition. Furthermore, the use of brewing by-products as a source of functional cardioprotective lipids warrants further investigation and valorisation.


2013 ◽  
Vol 110 ◽  
pp. 80-92 ◽  
Author(s):  
Katja Guilini ◽  
Gritta Veit-Köhler ◽  
Marleen De Troch ◽  
Dirk Van Gansbeke ◽  
Ann Vanreusel

2004 ◽  
Vol 10 (1) ◽  
pp. 29-34 ◽  
Author(s):  
P. Sans ◽  
M. J. Andrade ◽  
S. Ventanas ◽  
J. Ruiz

Chemical parameters involved in technological meat quality for dry cured processing of Gascon pigs were studied in longissimus dorsi (LD) and biceps femoris (BF) muscles. Muscles from Gascon pigs showed 2.60 and 2.84% of intramuscular fat content, 23.64 and 22.14% protein content and 1.34 and 4.63mg of myoglobin per gram of muscle (respectively LD and BF). Intramuscular fat (IMF) and myoglobin levels were higher than those reported for commercial pigs, but lower than those previously found in Iberian pigs. A similar situation was detected in the fatty acid composition of neutral and polar lipids of both muscles. Thus, monounsaturated fatty acids (MUFA) in neutral lipids of Gascon pig muscles (LD and BF respectively) were 58.27 and 51.98%, while polyunsaturated fatty acids (PUFA) levels were 5.61 and 14.13% respectively; values similar to those found in Iberian pigs and quite different to usual values in commercial pig breeds. The same trend was found in polar lipids. Both muscles showed a low susceptibility to induced lipid oxidation, in agreement with their fatty acid composition. These results pointed out that meat from pigs of the Gascon breed showed optimal characteristics for dry cured processing.


HortScience ◽  
1990 ◽  
Vol 25 (10) ◽  
pp. 1262-1264 ◽  
Author(s):  
Charles F. Forney

Polar lipids were extracted from immature through overripe `Honey Dew' muskmelons (Cucumis melo L.) that were exposed to high or low levels of solar radiation. Fatty acid composition of the polar lipids changed and the percentage of unsaturated fatty acids increased as fruit ripened. The percentage of monounsaturated fatty acids palmitoleic and oleic acid as a percent of total fatty acids increased from 8% in melons of minimum maturity to >50% in overripe melons. Also, the ratio of unsaturated to saturated fatty acids increased from 2.2 to 5.0. Total polar lipid fatty acid compostion from middle mesocarp tissue (flesh) did not change as much during ripening as the polar lipid composition from the epidermis (peel). Peel tissue from the top of melons relative to the ground had unsaturation ratios of C18 fatty acids and C16 fatty acids 33% and 62% greater, respectively, than peel from the bottom of the melon. Melons of minimum maturity exposed to solar radiation had significantly more unsaturated C18 fatty acids than shaded melons. Increase in the percentage of unsaturated polar lipid fatty acids in `Honey Dew' melons may relate to increases in chilling tolerance reported to occur with ripening and solar exposure.


2018 ◽  
Author(s):  
Fuqiang Wang ◽  
Ying Wu ◽  
Ying Cui ◽  
Zuozhi Chen ◽  
Zhongyi Li ◽  
...  

Study of the ecology of mesopelagic fish is central to assessing the active biological pump in the ocean, especially in the mesopelagic layer. As a consequence of the small size and pressure change, traditional stomach content analysis is not useful for analyzing the feeding behavior of mesopelagic fish. The use of δ13C and fatty acid analyses can help to resolve this problem. The mesopelagic fish examined in this study were collected from the continental slope in the north of the South China Sea (SCS), and are compared with nearshore SCS fish and fish collected from the Southern Ocean. The unusually high lipid content of the mesopelagic fish resulted in △δ13C values (i.e., the difference in δ13C between unextracted and extracted tissues) exceeding 1‰, which is more than the enrichment factor in the food web. Thus, extraction of lipids was conducted prior to δ13C isotope analysis for the study of trophic interactions of mesopelagic fish. Compared with other fish, mesopelagic fish had high C18:1n-9/C18:1n-7 and C20:1n-9/ C18:1n-7 ratios, which confirms that plankton is their main dietary source. Diatoms comprise a higher proportion of phytoplankton in the Southern Ocean and a lower proportion in the SCS, and this is reflected in the C20:5n-3/C22:6n-3 (EPA/DHA) ratio in mesopelagic fish in each region. The low EPA/DHA ratio in SCS fish indicates that diatoms are not the main component in the diet of mesopelagic fish. The SCS mesopelagic fish had higher C20:4n-6/C22:6n-3 (ARA/DHA) and C20:4n-6/C20:5n-3 (ARA/EPA) ratios than fish in the Southern Ocean. This result suggests that physical factors (e.g., temperature) also affect the fatty acid composition of these fish, particularly because certain fatty acids enable the fish to better adapt to extreme environmental conditions. Future studies of the synthesis of fatty acids in particular species should take account of both the dietary sources and physical factors in their environment.


2018 ◽  
Author(s):  
Fuqiang Wang ◽  
Ying Wu ◽  
Ying Cui ◽  
Zuozhi Chen ◽  
Zhongyi Li ◽  
...  

Study of the ecology of mesopelagic fish is central to assessing the active biological pump in the ocean, especially in the mesopelagic layer. As a consequence of the small size and pressure change, traditional stomach content analysis is not useful for analyzing the feeding behavior of mesopelagic fish. The use of δ13C and fatty acid analyses can help to resolve this problem. The mesopelagic fish examined in this study were collected from the continental slope in the north of the South China Sea (SCS), and are compared with nearshore SCS fish and fish collected from the Southern Ocean. The unusually high lipid content of the mesopelagic fish resulted in △δ13C values (i.e., the difference in δ13C between unextracted and extracted tissues) exceeding 1‰, which is more than the enrichment factor in the food web. Thus, extraction of lipids was conducted prior to δ13C isotope analysis for the study of trophic interactions of mesopelagic fish. Compared with other fish, mesopelagic fish had high C18:1n-9/C18:1n-7 and C20:1n-9/ C18:1n-7 ratios, which confirms that plankton is their main dietary source. Diatoms comprise a higher proportion of phytoplankton in the Southern Ocean and a lower proportion in the SCS, and this is reflected in the C20:5n-3/C22:6n-3 (EPA/DHA) ratio in mesopelagic fish in each region. The low EPA/DHA ratio in SCS fish indicates that diatoms are not the main component in the diet of mesopelagic fish. The SCS mesopelagic fish had higher C20:4n-6/C22:6n-3 (ARA/DHA) and C20:4n-6/C20:5n-3 (ARA/EPA) ratios than fish in the Southern Ocean. This result suggests that physical factors (e.g., temperature) also affect the fatty acid composition of these fish, particularly because certain fatty acids enable the fish to better adapt to extreme environmental conditions. Future studies of the synthesis of fatty acids in particular species should take account of both the dietary sources and physical factors in their environment.


2002 ◽  
Vol 14 (3) ◽  
pp. 212-220 ◽  
Author(s):  
KATRINA L. PHILLIPS ◽  
PETER D. NICHOLS ◽  
GEORGE D. JACKSON

Lipid content, lipid class and fatty acid composition of four Southern Ocean cephalopod species – the myopsid Sepioteuthis australis and three oegopsids, Gonatus antarcticus, Moroteuthis robsoni and Todarodes spp. – were analysed. The lipid content of the digestive gland was consistently greater than that of the mantle, and was an order of magnitude greater in oegopsid species. The lipid class and fatty acid composition of the mantle and digestive gland also differed markedly in each species. Digestive gland lipid is likely to be of dietary origin, and large amounts of lipid in the digestive gland of oegopsids may accumulate over time. Thus the digestive gland is a rich source of fatty acid dietary tracers and may provide a history of dietary intake. However, the absolute amount of dietary lipid in the digestive gland of oegopsid species exceeds the absolute lipid content of mantle tissue. Therefore the overall lipid “signature” of an oegopsid may more closely resemble its prey species rather than its mantle tissue. When lipid techniques are used in dietary analysis of teuthophagous predators, squid may not be represented by a unique signature in analyses and their importance in the diets of predators may be underestimated.


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