Didier Montet

Fructose oleate synthesis in a fixed catalyst bed reactor

SummaryFructose oleate undergoes continuous synthesis in a fixed catalyst bed reactor using an industrial fixed lipase. The effects of the time spent in the reactor, substrate concentration and effluent recycling are studied. A yield of 83% is obtained by recycling the effluent 3 times.

Effect of water activity on enzymatic synthesis of alkylglycosides

Water activity (aw) was studied during biocatalyzed alkylglycoside synthesis using defated raw almond meal displaying a good β glucosidasic activity. Optimum aw were determined for several alcohols used for the alkylation of the sugar. Above and below optimum aw, yield decreased rapidly.

Carica papaya latex lipase : sn-3 stereoselectivity or short-chain selectivity ? Model chiral triglycerides are removing the ambiguity

Short-chain fatty acids are usually located at positionsn-3 in natural triglycerides, particulary in dairy fats. As a result, it is extremely difficult to differentiate betweensn-3 stereospecificity and short-chain typoselectivity in many lipases and acyltransferases that perform in this way. This ambiguity can be removed through successive use of a chiral triglyceride with a short fatty acid in positionsn-1 and of its racemic in controlled hydrolysis reactions. After checking that the proposed method effectively confirmed the type of activity of control biocatalysts (Candida cylindracea nonspecific lipase andMucor miehei 1–3 regiospecific lipase), we confirmed thatCarica papaya latex has a strictsn-3 stereospecificity.

A study of the influence of the growth media on the fatty acid composition in Candida lipolytica Diddens and Lodder

Candida lipolytica YB 423-12 is able to incorporate fatty acid from the culture medium when lipids are used as carbon substrate. The composition of cell lipids is largely dependent on that of the culture medium. An important Δ 9 desaturase activity acts on incorporated palmitic and stearic acids; and Δ 11-eicosenoic and erucic acids are shortened to oleic acid.

Enzymatic synthesis of N-ε-acyllysines

Chemical synthesis of N-ε-acyllysines on an industrial scale corresponds to new requirements in the surfactant field; only one chemical synthesis process is currently known for this type of molecule. A number of organic synthesis conducted in the laboratory so far have not made it possible to consider industrial development. However, biotechnologically, it has been shown that this molecule is easily accessible using a commercially available fixed lipase. Synthesis is carried out by causing a triglyceride to react with the lysine either with or without a solvent. The latter method gives the best results at the current stage of research. Given the availability of at least one fixed lipase on the market today, and the possibility of directly applying the reaction using oils, this reaction could be scaled up rapidly for industrial development.

Determination of lipase specificities through the use of chiral triglycerides and their racemics

Abstract The previously published synthesis of defined chiral triglycerides has been extended to the synthesis of their racemics. The combined use of the chiral-racemic pair of a triglyceride can now be used to accurately define the effective specificity of a large number of lipases. As an example, we confirm unambiguously in this paper, the sn3 stereospecificity for the rabbit gastric lipase, the short chain typoselectivity for the Candida antartica lipase and the sn1 stereospecificity for the Pseudomonas aeruginosa lipase.

Synthesis of fatty hydroxamic acids catalyzed by the lipase of Mucor miehei.

Biotechnological synthesis of a new class of amphiphilic molecules—fatty hydroxamic acids—was carried out using the lipase ofMucor miehei by reacting hydroxyl amine with the fatty acids in their free or methyl ester form. Concurrently with enzymatic synthesis, chemical synthesis of hydroxamic fatty acids has also been developed by adapting methods that already existed for water-soluble acids. Different parameters were studied to determine the optimum operating conditions: temperature, molar ratio of reagents, quantity of biocatalyst and length of reaction. A general method, whatever the type of fatty acids used, is described.

Biocatalyzed octylglycoside synthesis from a disaccharide

By bringing lactose into contact with octanol in the presence of β-galactosidase and almond meal with a β-glucosidase activity, it is possible to simultaneously synthesize the octylglycosides corresponding to the two hexoses of the disaccharide. The reaction is optimized using an experimental plan.

CHIRAL SYNTHESIS OF A TRIGLYCERIDE : EXAMPLE OF 1-BUTYROYL 2-OLEOYL 3-PALMITOYL SN GLYCEROL

Abstract Chiral synthesis of 1-butyroyl 2-oleoyl 3-palmitoyl sn glycerol was achieved from a two-step reaction allowing more than 95% purity. 1-butyroyl 2-oleoyl 3-bromo sn glycerol was obtained from R(−) glycidyl butyrate through the high regioselective epoxide opening by the synergy reaction of oleic anhydride, lithium bromide and benzyltributylammonium bromide. The substitution of bromine was carried out by cesium palmitate, giving the expected molecule whose structure was checked by the usual stereospecific determination of glyceride distribution.

Biocatalysed deacidification: Reaction optimization on a model hyperacid oil

Enzymatic deacidification reaction of hyperacid oils, biocatalyzed by a lipase ofMucor miehei (Lipozyme), was optimized on a reconstituted acid oil, according to an experimental plan with the following variable parameters: pressure, temperature, proportion of biocatalyst. The optimum values defined (20 mm Hg, 60°C, 5.5% w/w of Lipozyme) allowed to determine reaction kinetics and to obtain a yield of 93%.