Jojoba oil wax esters and derived fatty acids and alcohols: Gas chromatographic analyses

  • Thomas K. Miwa
Technical

Abstract

HCl-catalyzed ethanolysis followed by saponification readily surmounts the resistance of long chain wax esters to direct hydrolysis by alkali. Additionally, choosing ethyl instead of methyl esters allows baseline separations between long-chain alcohols and corresponding esters in gas liquid chromatographic (GLC) analysis of total alcohol and acid components before saponification. Liquid wax esters were analyzed on a temperature-programmed 3% OV-1 silicone column. Geographical and genetic effects on the variability of jojoba oil composition were investigated with five different seed samples. Major constituents in jojoba seed oil from shrubs in the Arizona deserts, as indicated by GLC analyses of oil, ethanolysis product, isolated fatty alcohols and methyl esters of isolated fatty acids, were C40 wax ester 30%, C42 wax ester 50% and C44 wax ester 10%; octadecenoic acid 6%; eicosenoic acid 35%, docosenoic acid 7%, eicosenol 22%, docosenol 21% and tetracosenol 4%. Oil from smaller leaved prostrate plants growing along California’s oceanside showed a slight tendency toward higher molecular size than oils from the California desert and Arizona specimens. The wax esters are made up of a dispro-portionately large amount of docosenyl eicosenoate and are not a random combination of constituent acids and alcohols.Lunaria annua synthetic wax ester oil was used as a model for evaluating the analytical procedures.

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References

  1. 1.
    Mirov, N.T., Chemurg. Dig. 9(7):7–9 (1950).Google Scholar
  2. 2.
    Daugherty, P.M., H.H. Sineath and T.A. Wastler, Georgia Inst. Technol., Eng. Expt. Sta. Bull. No. 17 (1953).Google Scholar
  3. 3.
    Knoepfler, N.B., and H.L.E. Vix, J. Agr. Food Chem. 6:118–121 (1958).CrossRefGoogle Scholar
  4. 4.
    Yermanos, D.M., A. Kadish, C.M. McKell and J.R. Goodin, Calif. Agr. 22:(10):2–3 (1968).Google Scholar
  5. 5.
    Wells, F.B., U.S. Patent 2,450,403 (1948).Google Scholar
  6. 6.
    Molaison, L.J., R.T. O’Connor and J.J. Spadaro, JAOCS 36:379–382 (1959).Google Scholar
  7. 7.
    Knoepfler, N.B., E.J. McCourtney, L.J. Molaison and J.J. Spadaro, Ibid. 36:644–648 (1959).CrossRefGoogle Scholar
  8. 8.
    Fore, S.P., H.P. Pastor, J.P. Hughes and W.G. Bickford, Ibid. 37:387–390 (1960).Google Scholar
  9. 9.
    Marvel, C.S., D.M. Paisley, G.M.A. Khattab, W.G. Bickford and S.P. Fore, J. Polym. Sci. 44:289–294 (1960).CrossRefGoogle Scholar
  10. 10.
    Greene, R.A., and E.O. Foster, Bot. Gaz. 94:826–828 (1933).CrossRefGoogle Scholar
  11. 11.
    Green, T.G., T.P. Hilditch and W.J. Stainsby, J. Chem. Soc. 1936:1750–1755.Google Scholar
  12. 12.
    McKinney, R.S., and G.S. Jamieson, Oil Soap 13:289–292 (1936).CrossRefGoogle Scholar
  13. 13.
    Eckey, E.W., “Vegetable Fats and Oils,” Reinhold, New York, 1954, p. 612–613.Google Scholar
  14. 14.
    Hilditch, T.P., “The Chemical Constitution of Natural Fats,” Third edition, Wiley, New York, 1956, p. 277.Google Scholar
  15. 15.
    Warth, A.H., “The Chemistry and Technology of Waxes,” Second edition, Reinhold, New York, 1956, p. 302–307.Google Scholar
  16. 16.
    Miwa, T.K., and I.A. Wolff, JAOCS 39:320–322 (1962).Google Scholar
  17. 17.
    Miwa, T.K., and I.A. Wolff, Ibid. 40:742–744 (1963).CrossRefGoogle Scholar
  18. 18.
    Miwa, T.K., K.L. Mikolajczak, F.R. Earle and I.A. Wolff, Anal. Chem. 32:1739–1742 (1960).CrossRefGoogle Scholar
  19. 19.
    Miwa, T.K., JAOCS, 40:309–313 (1963).Google Scholar
  20. 20.
    Hansley, V.L., Ind. Eng. Chem. 39:55–62 (1947).CrossRefGoogle Scholar
  21. 21.
    Mikolajczak, K.L., T.K. Miwa, F.R. Earle, I.A. Wolff and Q. Jones, JAOCS 38:678–681 (1961).CrossRefGoogle Scholar
  22. 22.
    Wilson, T.L., C.R. Smith and I.A. Wolff, Ibid. 39:104–105 (1962).CrossRefGoogle Scholar
  23. 23.
    Miwa, T.K., Anal. Chem. 41:307–310 (1969).CrossRefGoogle Scholar

Copyright information

© The American Oil Chemists’ Society 1971

Authors and Affiliations

  • Thomas K. Miwa
    • 1
  1. 1.Northern Regional Research LaboratoryPeoria

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