Acetylenic acids ofAlvaradoa amorphoides seed oil.

Oil from the seed ofAlvaradoa amorphoides Liebm. (Simaroubaceae) collected in Mexico contains two acetylenic fatty acids previously unknown in seed oils, 15% of 17-octadecen-6-ynoic and a trace amount of 6-eicosynoic acid. The predominant fatty acid (58%) in the oil is 6-octadecynoic (tariric). Both the δ6 and δ9 series of hexadecenoic, octadecenoic, octadecadienoic, and octadecatrienoic acids were found, but only the δ6 isomer of eicosenoic acid (1.4%) was detectec. The mono- and dienoic acids make up about 19% of the total oil. The remainder consists mostly of saturated acids (6.3%). Techniques used in isolation and identification of the acids included thin layer and gas chromatography, IR, UV, NMR and mass spectroscopy, and ozonolysis coupled with gas chromatography.

Occurrence ofCis-6-hexadecenoic acid as the major component ofThunbergia alata seed oil.

An unusual series of monoenoic fatty acids constitutes about 85% of the total acids in seed oil fromThunbergia alata. The major component in the oil,cis-6-hexadecenoic acid (82%), is accompanied by the homologous 4-tetradecenoic (ca. 0.2%) and 8-octadecenoic (1.8%) acids. Another homologous series is represented by 5-tetradecenoic (ca. 0.2%), 7-hexadecenoic (1.8%) and the familiar 9-octadecenoic (4.4%) acids. Traces (<0.1%) of three other acids, 6-tetradecenoic and 10- and 11-octadecenoic, are also present along with palmitic (5.8%), stearic (0.6%) and linoleic (2.2%) acids. Some of the monoenoic acids have not previously been known to occur in seed oils.

OxygenatedTrans-3-olefinic acids in aStenachaenium seed oil.

Interesting differences were found in oils from two samples ofStenachaenium macrocephalum (Compositae) seed with dissimilar storage histories. One contained significant amounts of epoxy acids (6.5%) and hydroxy conjugated dienoic acids (5.6%), but the other contained no more than 1% of these oxygenated acids. Characterization of components in the former oil established that the principal epoxy acid (4.0%) is the previously unknowncis-9, 10-epoxy-trans-3,cis-12-octadecadienoic acid. The conjugated dienols include two additional new acids with Δ3 unsaturation (2.5%): 9-hydroxy-trans-3,-trans-10,cis-12-octadecatrienoic and 13-hydroxy-trans-3,cis-9,trans-11-octadecatrienoic acoids. The nonoxygenated acids, except for the large amount (40%) oftrans-3,cis-9,cis-12-octadecatrienoic, are those that commonly occur in seed oils.

TheTrans-6 fatty acids ofPicramnia sellowii seed oil.

The C18 monoenoic acids inPicramnia sellowii Planch. seed oil include bothcis-andtrans-6-octadecenoic acids, as well as oleic acid. The hexadecenoic acids are also thecis- andtrans-Δ6-isomers, and the eicosenoic acids have Δ6-unsaturation of undetermined geometric configuration. The C18 polyenoic acids detected are 9,12- and 6,9-octadecadienoic and 9,12,15- and 6,9,12-octadecatrienoic acids. Partial investigation of another species,P. pentandra Sw., revealed its oil to have a similar fatty acid composition.

Search for new seed oils. XV. Oils of boraginaceae.

In a search for a preferred source of gamma-linolenic (all-cis-6,9,12-octadecatrienoic) acid, seed oils of 33 species of Boraginaceae were examined. The desired triene was found primarily in the subfamily Boraginoideae in amounts ranging from 0.2 to 18%. Oils of this subfamily also contain 0.2 to 15% of the tetraene, all-cis-6,9,12,15-octadecatetraenoic acid. Total unsaturation and the relative proportions of the common acids varied widely in oils of the family. Monoene predominated in the subfamily Cordioideae, diene in Heliotropioideae, and a diverse composition among the Boraginoideae; seven had iodine values of 200 or above.Cordia verbenacea seed oil was unique among those examined in having 43% of C(20) acids and 23% of components more volatile in gas chromatography than the usual triglycerides.

(S)-1,2-diacyl-3-acetins: Optically active triglycerides fromEuonymus verrucosus seed oil.

The seed oil ofEuonymus verrucosus Scop., family Celastraceae, contains more than 90% 1,2-diacyl-3-acetins (monoacetotriglycerides). The constituent triglyceride acids, other than acetic, are the usual long-chain fatty acids.Thin-layer chromatography (TLC), infrared (IR) and hydrolysis with pancreatic lipase indicate that the acetic acid is esterified exclusively on the outer glycerol carbon atoms. The isolated mixed monoacetotriglycerides exhibit optical rotation caused by asymmetry of the central glycerol carbon atom. Comparison with synthetic products of known configuration shows that the natural material is essentially all (S)-1,2-diacyl-3-acetin.IR, TLC and GLC analyses indicate the presence of monoacetotriglycerides in seven other species of Celastraceae and five species in three other plant families in amounts from 13 to 98%.

Search for new industrial oils. XIV. Seed oils of labiatae.

Seed of 194 species in 56 genera of Labiatae, representing six of the eight subfamilies, were analyzed for oil and protein and for fatty acid composition of the oil. The oils are diverse and include some that contain up to 70% oleic acid, 79% linoleic acid, or 72% linolenic acid. An allenic function occurs in a third of the samples from the subfamily Stachyoideae and in the one sample analyzed from the Prasioideae. A method for determining the allene was devised. Oils fromTeucrium species containtrans unsaturation in unidentified components. Oils from twoLamium species have both allenic andtrans unsaturation. Two species ofThymus appear to produce hydroxy acids.

Determination of petroselinic acid by microreactor chromatography.

The microreactor-ozonolysis technique was applied to the quantitative determination of the relative amounts of petroselinic and oleic acids in seven Umbelliferae seed oils. The operation was easy and rapid. Results were excellent when the method was tested on ester mixtures of known composition. When used on esters prepared from Umbelliferae seed oils, the method gave results comparable with those found by another procedure, also described, which combined thin-layer chromatography with either gas-liquid chromatography or ultraviolet spectrophotometry.

Thetrans-3-enoic acids ofGrindelia oxylepis seed oil.

trans-3-Hexadecenoic acid (14%) and the previously unreportedtrans-3-octadecenoic acid (2%) have been identified in seed oil ofGrindelia oxylepis Greene, Compositae. Evidence was also found for the existence of other acids withtrans-3 unsaturation.

Compositional variation in seed oils of theCrepis genus.

Seed oils from eight species of the genusCrepis (family Compositae) fall into three groups differing in chemical composition. Besides conventional fatty acids the oils contain either vernolic acid (47-68%), crepenynic (36-65%), or both (18-35% vernolic and 7-11% crepenynic). Within any one section of the genus, the oils are chemically similar, among the limited groups of samples examined.

Identification and distribution of epoxyacyl groups in new, natural epoxy oils.

New high-epoxy vegetable oils from nine species representing three plant families and four genera have been investigated. The epoxyacyl moiety in at least one oil from each genus was characterized and shown to be the (+)-vernoloyl (cis-12,13-epoxy-cis-9-octadecenoyl) group. Intraglyceride distribution studies revealed a general preference of the (+)-vernoloyl groups for the beta-position of triglyceride molecules. Interglyceride distribution of (+)-vernoloyl groups was studied in three oils and found not to agree with predictions based on either 1,2,3-random or 1,3-random-2-random distribution. A striking exception to the general intraglyceride distribution pattern was discovered in the monoepoxy triglyceride fraction fromEuphorbia lagascae seed oil.