Method for producing lipids comprising structural units based on glycerides of hydroxycarboxylc acids

1. A method for producing lipids comprising structural units based on glycerides of at least one of 3-hydroxybutyric acid and 3-alkoxybutyric acid,

wherein at least one glyceride of the general formula (I)

R 1 O—CH 2 —CH(OR 2 )—CH 2 —OR 3   (I)

wherein in the general formula (I) the radicals R 1 , R 2 and R 3 , identical or different, each independently of one another represent,

hydrogen,

a radical C 1 -C 11 -alkyl-C(O)—,

a radical C 12 -C 29 -alkyl-C(O)—,

however, with the proviso that at least one of the radicals R 1 , R 2 and R 3 does not represent hydrogen,

is reacted with at least one 3-hydroxybutyric acid, 3-alkoxybutyric acid and their derivatives of the general formula (II)

CH 3 —CH(OR 4 )—CH 2 —C(O)OR 5   (II)

wherein in the general formula (II)

the radical R 4 represents hydrogen or a radical C 1 -C 30 -alkyl-C(O)—,

the radical R 5 represents hydrogen or C 1 -C 4 -alkyl,

wherein the reaction is carried out in the absence of any solvents and

wherein the reaction is carried out in the presence of an enzyme as a catalyst,

so that, as a reaction product, there is obtained a mixture of at least two different lipids comprising structural units based on glycerides of at least one of 3-hydroxybutyric acid and 3-alkoxybutyric acid of the general formula (III)

R 6 O—CH 2 —CH(OR 7 )—CH 2 —OR 8   (III)

wherein in the general formula (III) the radicals R 6 , R 7 and R 8 , identical or different, each independently of one another represent

a radical C 1 -C 11 -alkyl-C(O)—,

a radical C 12 -C 29 -alkyl-C(O)—,

a radical CH 3 —CH(OR 4 )—CH 2 —C(O)—, wherein the radical R 4 has the meaning defined hereinabove,

however, with the proviso that one or two of the radicals R 6 , R 7 and R 8 represents a radical CH 3 —CH(OR 4 )—CH 2 —C(O)—.

2. The method according to claim 1 ,

wherein the catalyst is recycled after the reaction; and

wherein the enzyme is selected from the group consisting of synthetases, catalases, esterases, lipases and combinations thereof.

3. The method according to claim 1 ,

wherein the enzyme is derived from Candida antarctica, Mucor miehei ( Rhizomucor miehei ), Thermomyces lanuginosus, Candida rugosa, Aspergillus oryzae, Pseudomonas cepacia, Pseudomonas fluorescens, Rhizopus delemar and Pseudomonas sp. and combinations thereof; and

wherein the enzyme is used in immobilized form on a carrier; and

wherein the enzyme is recycled after the reaction.

4. The method according to claim 1 ,

wherein the enzyme is used in amounts, based on the total amount of starting compounds (I) and (II), in the range of from 0.001% by weight to 20% by weight.

5. The method according to claim 1 ,

wherein, in the case that in general formula (II) the radical R 5 denotes hydrogen, the anhydride of the general formula (IIa)

[CH 3 —CH(OR 4 )—CH 2 —C(O)] 2 O  (IIa)

wherein in the general formula (IIa) the radical R 4 has the meaning defined hereinabove,

is used instead of the free acid.