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Crambe abyssinica andLunaria annua, members of the Cruciferae family, have seed oil glycerides containing ca. 55–65% of C22 and C24 unsaturated fatty acids. Fatty acids were prepared by saponification; fatty alcohols, by sodium reduction of glycerides; liquid wax esters, byp-toluenesulfonic acid-catalyzed reaction of fatty acids with fatty alcohols; and methyl esters, by reaction of fatty acids with diazomethane. Solid hydrogenated glyceride oils and wax esters were compared with several commercial waxes. Chemical and physical constants were determined for the seed oils and their derivatives. Position of unsaturation in theCrambe fatty acids was determined by gas chromatographic analysis of the permanganate-periodate degradation products. The major dicarboxylic acid was brassylic (C13), proving the docosenoic acid to be erucic.

The syntheses of (±)-l-cyano-2,3-epithiopropane (3), (±)-l-cyano-3,4-epithiobutane (2), and (±)-l-cyano-4,5-epithiopentane (4) are described, as are the formation of 3 from allylglucosinolate, and its aglucone, by a Crambe abyssinica preparation. Short term tests of 2-4 for mutagenicity and carcinogenicity gave weakly positive results.

2 S -1-Cyano-2-hydroxy-3,4-epithiobutanes ( erythro and threo ) isolated from the seed of Crambe abyssinica , were fed to groups of six weanling rats at levels of 0, 75, 150 or 300 ppm in the diet for 90 days. The higher dose groups showed poor growth and increased serum levels of alkaline phosphatase, total bilirubin, glutamic-oxaloacetic transaminase, glutamic-pyruvic transaminase and ornithine carbamyl transferase. The severity and occurrence of renal and hepatic lesions were dose-dependent. Renal alterations consisted of hypertrophy of proximal tubular epithelial cells with prominent karyomegaly. Hepatic lesions consisted primarily of megalocytosis of the hepatocytes and bile-duct hyperplasia with disruption of the normal hepatic architecture. Half of the rats in the high-dose group had karyomegaly of pancreatic acinar cells.

Of major importance in the food economy of the world is the ever-increasing production of oil-rich seeds. With a world production in 1975–76 of over 130,000,000 tons of oilseeds, from which over 27,000,000 tons of oil were extracted, a fuller understanding of the biochemical mechanisms involved in the formation of oils in these seeds has considerable relevance.

The phase behavior of the seed oils from different strains ofBrassica napus, Brassica campestris, Sinapis alba, Crambe abyssinica andErysimum orientale is reported. The rapeseed oils and white mustardseed oils include products from plant breeding work in Canada and Sweden. The experimental technique includes the continuous recording of X-ray diffraction patterns vs. temperatures between −50 C and complete melting of the most stable solid phases with a new DPT (Diffraction-Pattern-Temperature) camera. The crystallization and melting of oils with an erucic acid content above 8% can be described in terms of the polymorphic phases α, β2 and β1 (in the order of increasing stability). The designation β2 is tentative as the phase cannot be classified unambiguously by X-ray diffraction data alone. The phase transition temperatures for a certain species form continuous functions of the erucic acid content, thus providing a basis for the prediction of some of the properties that are relevant for the utilization of the oils in the food industry.

Ultrasonic treatment releases thioglucoside glucohydrolase (thioglucosidase) from insoluble particles of Crambe abyssinica seed meal. The crude enzyme is optimally activated by 10−2 M ascorbate, requires a reducing agent for stability, and is inhibited by 10−3 M p-chloromercuribenzenesulfonate.Chromatography of a meal extract on cross-linked dextran separates two enzyme fractions. About 80% of the activity elutes at an apparent molecular weight of 110 000; the remainder elutes at the void volume. Both crude soluble enzyme and the fractions from the dextran column produce goitrin from epi-progoitrin, but in the presence of ferrous ion the chief aglucon product becomes 1-cyano-2-hydroxy-3-butene. The Michaelis constant (of the major peak) at pH 5 is 0.004 M. Ferrous ion produces substrate inhibition at high epi-progoitrin levels. Sequential fractionation of meal extract by ammonium sulfate precipitation and by chromatography on cross-linked dextran effects an 80-fold purification.

The technical properties of Crambe abyssinica oil prompted the co‐operation between a research institute and a lubricant producer to determine some possible industrial applications. The results confirm the special physico‐chemical characteristics of crambe oil which, compared with some vegetable or synthetic oils, shows a higher heat removal capability and interesting lubrication characteristics. The research establishes that crambe oil could be a good hydraulic fluid. These findings led to the cultivation of a suitable area with Crambe abyssinica to obtain a sufficient amount of oil for lubricant formulation on a commercial scale.

Two Brassicaceae (Iberis amara L. selection ISCI14 and Rapistrum rugosum All. selection ISCI4) and a Capparidacea (Cleome hassleriana L. selection ISCI2) possessing glucosinolates whose degradation products exhibit high fungitoxic activity in vitro were assayed as biocidal plants in a green manure simulation. The trials were carried out in pots, using aboveground fresh plant tissues incorporated at a realistic field rate into soil naturally infected by Pythium sp. The effect of these plant tissues on total fungal populations and Pythium sp. were compared with Crambe abyssinica H. cv. Mario, a Brassicacea containing glucosinolates whose degradation products exhibit low fungitoxic activity in vitro, and a plant (Helianthus annuus L.) not containing glucosinolates. All green manure treatments induced increases in total fungi over a 10-week period, showing an enhanced microflora level compared with untreated soil. Pythium sp. was strongly suppressed by the C. hassleriana, I. amara, and R. rugosum selections, while sunflower and crambe treatments increased Pythium sp. in a manner similar to that observed for total fungal population. These findings indicate that the green manures assayed suppress Pythium sp. and also induced an increase in total soil microbial activity.

An aqueous suspension of Crambe abyssinica seed flour efficiently converted potassium allylglucosinolate (sinigrin) into 3,4-epithiobutanenitrile.

When 20 accessions of Crambe abyssinica Hochst. ex R.E. Fries and I of C. hispanica (L.) were tested in the greenhouse to determine the potential importance of the turnip aphid, Hyadaphis pseudobrassicae (Davis), and the green peach aphid, Myzus persicae (Sulzer), as pests of C. abyssinica and C. hispanica , both species of aphids were found capable of causing severe damage to both species of crambe in the proper environment. PL 247310 (an accession of C. abyssinica ) was resistant to the turnip aphid; all plants tested of other accessions of crambe were susceptible. Also, all plants tested of all accessions were susceptible to the green peach aphid. An infestation of turnip aphids will cause more damage to susceptible crambe than a comparable infestation of green peach aphids.

The fatty acid esters synthesis by transesterification of oils to produce biodiesel commonly involves methanol or ethanol as acyl acceptor. The transesterification of vegetable oils catalyzed by lipases is an alternative process for obtaining biodiesel. These biocatalysts working under mild conditions of temperature, allow for easy recovery of glycerol, synthesis of specific alkyl esters and transesterification of triglycerides with high concentrations of free fatty acids. The seeds of crambe (Crambe abyssinica) have a high oil content and great potential for biodiesel production [1]. In this way, the present work aims at crambe oil transesterification with methanol catalyzed by immobilized lipase Novozyme 435 (Candida antarctica).