Δ5-olefinic Acids Research Articles

Positional distribution of Δ5-olefinic acids in triacylglycerols from Torreya grandis seed oil: Isolation and purification of sciadonic acid

In recent years, in concern for human health, increasing attention was focused on sciadonic acid (SA), a unique Δ5-olefinic acid. Torreya grandis (T. grandis), a large, evergreen coniferous tree, whose seed yields rare and is known for a high level of SA. Triacylglycerols (TAGs) from the seeds of four different T. grandis varieties (Yuanfei, Xifei, Xiangyafei, and Zhimafei), were analyzed with respect to fatty acid profiles and positional distributions. The results indicated that SA represented the majority of the Δ5-olefinic acids in T. grandis seed oil. Irrespective of the variety, SA was naturally abundant at the sn-3 position of TAGs where they accounted for approximately 7.52%–12.00%. Based on this specific characteristic of Δ5-olefinic acids, T. grandis seed oil was subjected to a two-step enrichment process involving specific lipase-catalyzed ethanolysis and urea complexing. The content of SA in the fatty acid ethyl ester was increased to 80.14% from an initial value of 9.95%. These results suggested that the developed enrichment strategy was simple and effective in concentrating SA, and had the potential for commercial application.

Preparation of High Purity Δ5-Olefinic Acids from Pine Nut Oil via Repeated Lipase-Catalyzed Esterification.

Δ5-Olefinic acids have been characterized in gymnosperm plants and have been reported to have several biological health benefits. Δ5-Olefinic acids from pine nut oil were effectively concentrated by repeated lipase-catalyzed esterification. The pine nut oil contained three major Δ5-olefinic acids, namely taxoleic acid (C18:2 Δ5,9), pinolenic acid (C18:3 Δ5,9,12), and sciadonic acid (C20:3 Δ5,11,14). The fatty acids present in pine nut oil were selectively esterified with ethanol using Lipozyme RM IM from Rhizomucor miehei as a biocatalyst. The Δ5-olefinic acids were concentrated in the unesterified fatty acid fraction. The optimum molar ratio of the substrates (fatty acid:ethanol), temperature, the enzyme loading, and the reaction time were 1:7, 25°C, 5% of total substrate weight, and 6 h, respectively. There was no significant effect in the concentration of Δ5-olefinic acids when water was added in the reaction mixture. The same protocol and optimum conditions were employed for two times repeated lipase-catalyzed esterifications. In first lipase-catalyzed esterification, the Δ5-olefinic acids content in the pine nut oil increased from 17 mol% to 51 mol% with a yield of 40 mol%. In a second lipase-catalyzed esterification, with the Δ5-olefinic acids-concentrated fatty acids obtained from the first reaction as the substrate, the Δ5-olefinic acids content increased to 86 mol% with a yield of 15 mol%. Finally, a maximum Δ5-olefinic acids content of ca. 96 mol% with a yield of 6 mol% was obtained via a third lipase-catalyzed esterification.

Identification of the Botanical Origin of Pine Nuts Found in Food Products by Gas−Liquid Chromatography Analysis of Fatty Acid Profile

Pine nuts are traditionally used in various part of the world for the preparation of desserts or sauces or in salads. Local production is not sufficient to cope with the high demand of pine nuts around the world, and countries such as China or Pakistan are exporting much of their production to Western countries. Almost all the nuts that are traditionally consumed belong to the Pinus genus, but over the past years, the number of consumer complaints following consumption of commercial pine nuts increased. Some consumers experienced taste disturbance lasting for up to two weeks after consumption. Food safety agencies raised some concerns regarding pine nuts imported from Asia and their association with taste disturbance. However, even though a formal association has not been found to date, the Pinus genus comprises species that are not classified as edible and could be eventually used to adulterate edible species. Pinus spp. seed lipids are known to contain very specific polyunsaturated fatty acids know as Delta5-olefinic acids. Seed fatty acid profile of conifers had been used in the past as a taxonomic marker, and in the present study to identify the botanical origin of pine nut in nine commercial products. Fast gas-liquid chromatography (GLC) was used to resolve the complete fatty acid profile of Pinus spp. samples in less than 5 min. A diagnostic index based on the relative levels of the main fatty acids including distinctive Delta5-olefinic acids was used to identify botanical origins. Results revealed the occurrence of the following Pinus spp. in commercial products: P. pinea, P. koraiensis, P. gerardiana, P. armandii and P. massoniana. The later two species, known as Chinese white pine and Chinese red pine, are only cultivated in China and are not listed as common source of edible pine nuts by the Food and Agriculture Organization (FAO). The present study shows that the botanical origin of pine nuts can be identified in products based on the fatty acid profile.

Structures, practical sources (gymnosperm seeds), gas-liquid chromatographic data (equivalent chain lengths), and mass spectrometric characteristics of all-cis Δ5-olefinic acids

Structures, practical sources (gymnosperm seeds), gas-liquid chromatographic data (equivalent chain lengths), and mass spectrometric characteristics of all-cis Δ5-olefinic acids

Structures, practical sources (gymnosperm seeds), gas-liquid chromatographic data (equivalent chain lengths), and mass spectrometric characteristics of all-cis Δ5-olefinic acids

In view of the increasing interest of lipid researchers in the biological effects of all-cis Δ5-unsaturated polymethylene-interrupted fatty acids (Δ5-UPIFA) from vegetable origin, this paper is concerned with their occurrence in practical sources (gymnosperm seeds), structures, and identification by gas-liquid chromatography (GLC) and mass spectrometry (MS). The use of equivalent chain lengths (ECL) determined by calculations based on available standards, in close agreement with data determined with easily available commercial gymnosperm seeds specific for each Δ5-UPIFA, allows identification of all Δ5-UPIFA. These tentative identifications are supported by GLC-MS of the appropriate (4, 4-dimethyloxazoline and picolinyl ester) derivatives. ECL are particularly useful to identify Δ5-UPIFA in tissue lipids from animals experimentally fed oils containing these acids, with no interference with polyunsaturated fatty acids of endogenous origin.

Taxonomy of Pinus species based on the seed oil fatty acid compositions

The fatty acid compositions of the seed oils from ten pine species have been established by capillary gas-liquid chromatography of the methyl esters. With regard to either normal fatty acids or Δ5-olefinic acids, the general pattern of fatty acids did not differ from that of other pine seed oils reported previously. The main fatty acid was linoleic (9,12–18:2) acid (44.4–57.1%), followed by either oleic (9–18:1) acid (13.4–24.5%) or pinolenic (5,9,12–18:3) acid (1.5–25.2%). When applying multivariate analyses to the chemometric data (13 variables) of 49 pine species (ca. 40% of the living pine species), it was possible to distinguish between several sections: Pinea, Longifolia, Halepensis, Ponderosa-Banksiana, Sylvestris, and Cembra. The latter section was clearly divided into two sub-groups. A few species that presented a low overall content of Δ5-olefinic acids, and that grow in warm-temperate regions, were isolated from the bulk of other pine species. It is hypothesized that Δ5-olefinic acids might be related to cold-acclimation.

91 Δ5 olefinic acids extracted from pine tree seeds decrease serum triglyceride levels in rats

91 Δ5 olefinic acids extracted from pine tree seeds decrease serum triglyceride levels in rats

Chemotaxonomic differentiation of conifer families and genera based on the seed oil fatty acid compositions: multivariate analyses

The fatty acid compositions of seed oils from 34 conifer species, mainly Pinaceae and secondarily Cupressaceae, have been determined by gas-liquid chromatography of the methyl esters. As noted in earlier studies, these oils were characterized by the presence of several Δ5-olefinic acids, i.e., 5,9-18:2, 5,9,12-18:3, 5,9,12,15-18:4, 5,11-20:2, 5,11,14-20:3, and 5,11,14,17-20:4 acids, in addition to the more common saturated, oleic, linoleic and α-linolenic acids. Based on these fatty acid compositions, and on those established in earlier systematic studies (totalling 82 species), we established a chemotaxonomic grouping of the main conifer families, i.e., of the Pinaceae, Taxodiaceae, Cupressaceae, and Taxaceae. This was achieved using multivariate analyses (principal component analysis and discriminant analysis). The fatty acids that discriminate best in this classification are the 5,11,14,17-20:4, 9,12,15-18:3 and 5,9,12-18:3 acids. Moreover, it was possible to differentiate between several genera of the Pinaceae: Pinus (including Tsuga and Pseudotsuga), Abies, Cedrus, and Picea plus Larix, represented quite distinct groups. Other fatty acids such as oleic, linoleic, and 5,9-18:2 acids were also important for this purpose. The fatty acid compositions, and particularly the Δ5-olefinic acid contents of conifer seed oils, may thus be applied to the chemosystematic distinction among conifer families as well as genera of the Pinaceae.