Characterization of trans‐monounsaturated alkenyl chains in total plasmalogens (1‐O‐alk‐1′‐enyl‐2‐acyl glycerophospholipids) from sheep heart

Abstract

In the present study, we investigated the alkenyl chains from sheep heart plasmalogens (1-O-alk-1'-enyl-2-acyl glycerophospholipids) after their conversion into trimethylene dioxyalkanyl (TMDOA) derivatives. Particular attention was given to monounsaturated alkenyl chains (C18 mainly). For this purpose, a combination of silver ion TLC and GLC on highly polar, very long capillary columns was applied to TMDOA derivatives. Approximately 30 different alkenyl chains could be separated, and the main observation was that the component previously reported as a cis-9 18:1 alkenyl chain in plasmalogens embraces in fact a wide range of trans and cis isomers, in amounts equal to 7.9 and 5.6%, respectively, of total alkenyl chains. Concerning the trans-monoenoate fraction, isomers with their ethylenic bond spanning from delta6-delta8 to delta16 were tentatively identified on the basis of their distribution profile, which was similar to that of trans-18:1 acids prepared and isolated from sheep adipose tissue. The main trans-monoenoic C18 alkenyl chain in sheep heart plasmalogens would thus have its double bond in position 11, which seems logical, as alkenyl chains are derived from the corresponding alcohols, themselves issued from the corresponding FA, and in this particular case, vaccenic (trans-11 18:1) acid. cis-Monoenoic C18 alkenyl chains also appear more complex than realized earlier, showing in particular isomers with their ethylenic bond farther than the delta9 position, in addition to the main isomer derived from oleic acid. Several trans-16:1 alkenyl chains could be observed (totaling ca. 1%), but cis-16:1 isomers were present in trace amounts only.

Breed effect on quality veal production in mountain areas: emphasis on meat fatty acid composition

“…The results of this study also showed the presence of trans double bonds in the aldehyde moiety of the plasmalogenic lipids, evidenced by the presence of 11t-18:1 DMA (Table 4). These findings are consistent with those reported by Wolff (2002), and later confirmed by Kraft et al (2008) and Aldai et al (2011).…”

Length of concentrate finishing affects the fatty acid composition of grass-fed and genetically lean beef: an emphasis on trans-18:1 and conjugated linoleic acid profiles

“…It would appear, however, that increased dietary 18:3n-3 is generally associated with higher levels of plasmalogens, but this should be confirmed by comparing appropriate diets using the same breed. The results of this study clearly showed that the trans fatty acid metabolites formed by rumen bacteria were incorporated into plasmalogenic lipids (Table 3), as was previously demonstrated by Wolff (2002). The ratio of the 11t-18:1/10t-18:1 FAME and DMA moieties are shown in Tables 2 and 3, respectively, and are presented for comparison in Figure 2.…”

“…This is understandable as increased levels of fat in muscle tissue are mainly associated with triacylglycerols and not phospholipids, and plasmalogens being phospholipids would thus not be affected. We also considered whether different dietary fatty acids, such as 18:2n-6 and 18:3n-3, could affect the plasmalogenic content in muscle tissue, even though these unsaturated fatty acids are not incorporated into plasmalogenic lipids (Horrocks, 1972;Wolff, 2002). It would appear, however, that increased dietary 18:3n-3 is generally associated with higher levels of plasmalogens, but this should be confirmed by comparing appropriate diets using the same breed.…”

Detailed Dimethylacetal and Fatty Acid Composition of Rumen Content from Lambs Fed Lucerne or Concentrate Supplemented with Soybean Oil

“…Santercole et al [14] reported that the extent of AME formation from DMA is a function of number of variables, including injection temperatures, injection parameters and mode of injection. To overcome this problem some authors converted DMA in other stable derivatives [14], [18]. In our experiment, we did not observe the formation of AME, thus no degradation of DMA occurred during the injection of the sample.…”

“…The occurrence of unsaturated DMA chains, mainly 16∶1 and 18∶1, have been described in pure [6] and fractionated [23] rumen bacteria, however no discussion about their origin was reported. Additionally, more than 17 alk-1-enyl ethers, including 18∶1 isomers, containing cis and trans double bonds, were identified in sheep heart [18] and meat [14] plasmalogens. Both studies suggested that the vinyl ether is formed by conversion of the corresponding FA via an alcohol intermediate, following the known aerobic pathway in which the vinyl ether bond is formed at an early stage of the plasmalogen biosynthesis [25]; [31].…”