Long-chain, symmetrically unsaturated ␣,-dicarboxylic acid methyl esters (C 18 , C 20 , C 26 ) were obtained by the catalytic metathetical condensation of 9-decenoic, 10-undecenoic, and 13-tetradecenoic acid methyl esters, respectively, with the homogeneous Grubbs catalyst bis(tricyclohexyl phosphine) benzylidene ruthenium dichloride dissolved in methylene chloride. The dicarboxylic acid esters were epoxidized chemoenzymatically with H 2 O 2 /methyl acetate with Novozym 435 , an immobilized lipase B from Candida antarctica. Polyesters from symmetrically unsaturated or epoxidized ␣,-dicarboxylic acid methyl esters with 1,3-propanediol or 1,4-butanediol, respectively, were achieved by enzymatic polycondensation with the same biocatalyst applied. With 1,3-propanediol as a substrate, the linear unsaturated and epoxidized polyesters had molecular weights of 1950 -3300 g/mol and melting points of 47-75°C, whereas with 1,4-butanediol as a substrate, the resulting polyesters showed higher molecular weights, 7900 -11,600 g/mol, with similar melting points of 55-74°C.

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Crambe oil and camelina oil were transesterified with oleyl alcohol, the alcohols derived from crambe and camelina oils, n-octanol or isopropanol using Novozym 435 (immobilized lipase B from Candida antarctica), Lipozyme IM (immobilized lipase from Rhizomucor miehei), and papaya (Carica papaya) latex lipase as biocatalysts. The highest conversions to alkyl esters were obtained with Novozym 435 (up to 95%) in most cases, whereas Lipozyme IM and papaya latex lipase gave lower (40 to 50%) conversions. The conversions with long-chain alcohols (oleyl alcohol, crambe alcohols, and camelina alcohols) were higher (40 to 95%) than with mediumchain n-octanol (30 to 85%). Isopropyl esters of crambe oil and camelina oil were obtained with rather low conversions using Novozym 435 (<40%) and Lipozyme IM (about 10%) as biocatalysts, whereas with papaya latex lipase no isopropyl esters were formed. The conversions of crambe oil and camelina oil to oleyl and n-octyl esters using Novozym 435 as biocatalyst were hardly affected by the ratio of the substrates, but with Lipozyme IM the conversions to alkyl esters distinctly increased with an excess of alcohol substrate.Interest in lipase-catalyzed preparation of wax and bio-esters has grown in the last few years because of the possibility to obtain a wide variety of high-quality products under mild reaction conditions utilizing the substrate selectivity of such biocatalysts (1-9). The alcoholysis of triacylglycerols from vegetable oils with fatty alcohols, catalyzed by lipases, leads to a mixture of long-chain and very long chain wax esters with properties potentially suitable for applications in cosmetics and lubricants (10-15).In an accompanying paper the alkali-catalyzed alcoholysis of crambe oil and camelina oil to produce long-chain esters was studied (16). We report here the solvent-free lipase-catalyzed alcoholysis of these oils with long-chain alcohols, such as oleyl alcohol and alcohols derived from crambe oil and camelina oil with the aim to prepare wax esters as substitutes for jojoba oil. Moreover, lipase-catalyzed alcoholysis of crambe oil and camelina oil with n-octanol and isopropanol was carried out with the aim to prepare products similar to "bio esters" for cosmetics (17). Novozym 435 (immobilized unspecific lipase-B from Candida antarctica) (18-20), Lipozyme IM (immobilized sn-1,3-specific lipase from Rhizomucor miehei) (21,22), and papaya (Carica papaya) latex lipase (23-25) were used as biocatalysts. EXPERIMENTAL PROCEDURESMaterials. Novozym 435 and Lipozyme IM were kind gifts from Novo Nordisk Biotechnologie GmbH (Mainz, Germany). Carica papaya latex was purchased from Sigma-Aldrich-Fluka (Deisenhofen, Germany). The crude latex was ground and sieved to grains <0.8 mm.Refined oils from crambe (Crambe abyssinica) seeds and camelina (Camelina sativa) seeds were provided by the Institut für Pflanzenbau der Landesforschungsanstalt für Landwirtschaft und Fischerei Mecklenburg-Vorpommern (Gülzow, Germany). Fatty acid composition of the oils (designated by number of car...

Fatty acids obtained from seed oils of crambe (Crambe abyssinica) and camelina (Camelina sativa) via alkaline saponification or steam splitting were esterified using lipases as biocatalysts with oleyl alcohol and the alcohols derived from crambe and camelina oils via hydrogenolysis of their methyl esters. Long-chain wax esters were thus obtained in high yields when Novozym 435 (immobilized lipase B from Candida antarctica) and papaya (Carica papaya) latex lipase were used as biocatalysts and vacuum was applied to remove the water formed. The highest conversions to wax esters were obtained with Novozym 435 (> or =95%) after 4-6 h of reaction, whereas with papaya latex lipase such a high degree of conversion was attained after 24 h. Products obtained from stoichiometric amounts of substrates were almost exclusively (>95%) composed of wax esters having compositions approaching that of jojoba (Simmondsia chinensis) oil, especially when crambe fatty acids in combination with camelina alcohols or camelina fatty acids in combination with crambe alcohols were used as substrates.

The alcoholysis of crambe and camelina oils was carried out with oleyl alcohol, alcohols derived from crambe and camelina oils, and n-octanol using potassium hydroxide as catalyst to prepare alkyl esters. Conversions to alkyl esters were about 70% with oleyl alcohol, 20-45% with crambe and camelina alcohols, and 60% with n-octanol. The conversion to esters for crambe and camelina oil with oleyl alcohol and n-octanol increased with increasing molar excess of alcohol. Composition of the alkyl esters formed was as expected from the composition of the reaction partners.Crambe (Crambe abyssinica) and camelina (Camelina sativa) are less investigated oil plants, whose cultivation on poor nutrient soils is expected to be successful. These oil plants are regarded as industrial resources for different oleochemical applications because crambe oil is a rich source (1,2) of erucic acid (cis-13-docosenoic acid; ca. 56%), and camelina oil is a source (3) of α-linolenic acid (all-cis-9,12,15-octadecatrienoic acid; ca. 38%).The objective of the present work was to prepare alkyl esters of crambe and camelina oils that may have useful applications in lubricants and cosmetics. Transesterification (alcoholysis) of triacylglycerols with alcohols catalyzed by alkali (4-7) or acid catalysts (8,9) is well known and often used for the preparation of alkyl esters. We report here the potassium hydroxide-catalyzed alcoholysis of crambe and camelina oils with long-chain alcohols, such as oleyl alcohol and alcohols derived from crambe and camelina oils, for the preparation of mixtures of long-chain and very long chain wax esters resembling those of jojoba oil. Although the main chain lengths of the expected wax esters are C40 and C44, these esters may be useful as surrogates for jojoba (Simmondsia chinensis) wax esters, which have a main chain length of 42 carbon atoms (ca. 50% of the wax esters) (10,11). Jojoba wax is used in cosmetics, pharmaceuticals, and in the food industry because of its practically unchanged viscosity over a wide range of temperatures (12). Owing to the high price of the final product (inability to economically cultivate the plants) it is desirable to find a low-cost jojoba oil substitute (13). We also report the alkalicatalyzed alcoholysis of crambe and camelina oils with n-octanol and isopropanol. The goal was to obtain products similar to enzymatically prepared medium-chain and short-chain esters (14) with properties suitable for applications in cosmetics. EXPERIMENTAL PROCEDURESMaterials. Crambe and camelina were grown in experimental fields. The seeds and refined oils were supplied by the Institut für Pflanzenbau der Landesforschungsanstalt für Landwirtschaft und Fischerei Mecklenburg-Vorpommern (Gülzow, Germany). Fatty acid composition of the oils (designated by number of carbon atoms:number of cis-double bonds) was as follows. Crambe oil: 16:0 = 2%, 18:0 = 1%, 18:1 = 17%, 18:2 = 9%, 18:3 = 6%, 20:0 = 1%, 20:1 = 4%, 22:0 = 2%, 22:1 = 56%, 24:1 = 1%; camelina oil: 16:0 = 5%, 18:0 = 3%, 18:1 = 14%, 18:2 = 16%, 18:3 ...