Black currant seed oil (rich in both linoleic and gamma linolenic acids, 18:3 n-6).
"We conclude that gamma-linolenic-rich fatty acid preparations are likely to influence cardiovascular control, by mechanisms yet to be clarified." Department of Nutrition and Dietetics, King's College London, University of London, UK.
Traitler H, Winter H, Richli U, Ingenbleek Y.
The total lipid content of fruit seeds of the Ribes family ranges by weight from 18.3% in goose-berries (Ribes uva crispa) to 30.5% in black currants (Ribes nigrum). Isolation procedures and analytical methods (gas chromatography, mass spectrometry, high performance thin layer chromatography and stereospecific analysis) demonstrate that the oils from Ribes seeds contain up to 19% by weight of gamma-linolenic acid (gamma-LA, C18:3, n-6) in black currant oil. This last Ribes species thus constitutes one of the richest natural sources in gamma-LA yet described. These oils appear promising for critically ill patients who seem unable to convert linoleic acid into subsequent EFA fractions.
PMID: 6098796 [PubMed - indexed for MEDLINE]
J Agric Food Chem 2001 Jan;49(1):349-54
Gamma-linolenic acid and tocopherol contents in the seed oil of 47 accessions from several ribes species.
Goffman FD, Galletti S.
Institute of Agronomy and Plant Breeding, Georg-August-University of, Von-Siebold-Strasse 8, 37075 Gottingen, Germany, and Istituto Sperimentale per la Frutticoltura, Italian Ministry for Agricultural and Forestry Politics, Pergine Valsugana (TN), Italy.
Gamma-linolenic acid is an essential fatty acid for humans with delta-6-desaturase deficiency; it is a precursor of prostaglandins, prostacyclins, and tromboxanes; and it has antiinflammatory and antitumoral effects. Tocopherols are natural antioxidants with biological activity, heart/vascular, and cancer protective properties. The oil, gamma-linolenic acid, and tocopherol contents, as well as tocopherol composition, were investigated in the seed oil of a collection of 47 accessions belonging to various species of the genus Ribes. Differences for oil content among species were not significant. The highest total tocopherol content was found in R. nigrum (mean, 1716 mg kg(-)(1) oil), followed by R. rubrum (mean, 1442 mg kg(-)(1) oil). R. grossularia showed the lowest values for this trait (mean, 786 mg kg(-)(1) oil). The three species also differed strongly for tocopherol composition. R. rubrumwas distinguished by a higher concentration of delta-tocopherol (mean, 20.2%); R. grossularia displayed the highest percentage of gamma-tocopherol (mean, 70.0%), and R. nigrum showed the highest concentration for alpha-tocopherol (mean, 34.8%), the most biologically active among the four tocopherols. Regarding gamma-linolenic acid, the highest content was found in R. nigrum, which exhibited up to 15.8% of this essential fatty acid in the oil. R. grossularia and R. rubrum showed mean gamma-linolenic acid contents of 8% and 6.2%, respectively. The present study indicated that seeds of Ribes species, especially R. nigrum, could be used as sources of gamma-linolenic acid and natural vitamin E.
PMID: 11170598 [PubMed - in process]