HCl-cata]yzed 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 disproportionately 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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The predominating molecular species in jojoba oil iscis‐13‐docosenylcis‐11‐eicosenoate (erucyl jojobenoate), ranging from 31% to 45% of the extracted seed oil. Other alcohol/acid combinations contribute to the C42 molecular chain length so that this fraction constitutes a low of 41% to a high of 57% of the total wax esters. The positions of the exclusivelycis ethylenic bonds in the alcohol and acid moieties of the wax esters are 99% ω‐9 and 1% ω‐7. Only 2% of the alcohol and acid moieties were saturated when analyzed after saponification of the oil. Triglycerides were detected by gas chromatography in all of the more than 200 natural jojoba oil samples tested, a few of which had substantially more than the normal 1%. Among the many uses of jojoba oil cited here, the two most promising are the sulfurized oil as extreme‐pressure/extreme‐temperature lubricant additive and the natural or refined oil formulated into cosmetic products.

AND SUMMARYTwo analytical procedures for determining compositions ofjojoba liquid wax esters are described and compared. One, the more tedious, involves separation of wax ester homologs by high pressure liquid chromatography followed by determination of the acid and alcohol moieties from each homolog. The second allows rapid determination of wax ester composition by gas chromatographic separation of hydrogenated jojoba wax esters according to chain length, followed immediately by ancillary mass spectrometric identification of the acid and alcohol moieties. Double bonds in the alkyl chains in jojoba liquid waxes were almost exclusively (98%) w-9, when examined by gas chromatography/mass spectrometry (GC/MS) and ozonolysis/GC/MS.

Seeds from 37 species of plants in the family Crueiferae were analyzed for oil and protein, and the fatty acid composition of the oils was determined by gas-liquid chromatography. Erueic acid, generally considered characteristic of erueifer oils, occurs in about three-fourths of these species in amounts ranging from 3 to 59%. Some oils free of erueic ~cid contain up to 63% linolenie acid or up to 58% eicosenoic.