Inhibitors of sterol metabolism for their use to accumulate triglycerides in microalgae, and methods thereof

Patent metadata

Field	Value
Publication number	US-2016348138-A1
Application number	US-201515112886-A
Country	US
Kind code	A1
Filing date	Jan 27, 2015
Priority date	Jan 27, 2014
Publication date	Dec 1, 2016
Grant date	—

Abstract

The invention relates to a method for accumulating triacylglycerols in microalgae by inhibiting the sterol metabolism, N by incubating the microalgae with an inhibitor of sterol metabolism. The invention also relates to a method for producing fatty acids, biofuels, pharmaceutical or cosmetic compositions, and also food supplements, comprising a triacylglycerols accumulation step in microalgae according to the invention. Finally, the invention concerns the use of an inhibitor of sterol metabolism to accumulate triglycerides in microorganisms, and preferably microalgae.

First claim

1 . A method for triggering triacylglycerols accumulation in microalgae by inhibiting the sterol metabolism, by incubating the microalgae with an inhibitor of sterol metabolism.

2 . A method according to claim 1 , wherein the incubation step is implemented in a nitrogen medium.

3 . A method according to claim 1 , wherein the microalgae is selected from the group consisting of microalgae of the diatom phylum, the Chromalveolata phylum, and the Archaeplastidae phylum.

4 . A method according to claim 3 , wherein the microalgae is selected from the diatom micro-algae species Phaeodactylum tricomutum and Thalassiosira pseudonana , the Chromalveolata micro-algae species Nannochloropsis , and the Archaeplastidae micro-algae species Chlamydomonas, Ostreococcus , and Chlorella.

5 . A method according to claim 1 , wherein the inhibitor of sterol metabolism is a compound of formula (I) or a salt thereof:

wherein:
R 41 and R 42 , identical or different, represent a hydrogen atom, alkyl, alkenyl, alkynyl, or hydroxyl, —COR 4a or —COOR 4a group, in which R 4a represents a hydrogen atom, a linear or branched alkyl, aryl, heteroaryl group, optionally substituted with one or more groups independently selected from alkyl or cycloalkyl groups, or R 41 and R 42 form together an oxygen atom attached by a double bond;
R 43 represents a hydrogen atom, or an alkyl group; and
R 44 , R 45 and R 46 , identical or different, represent a hydrogen atom, an alkyl, alkoxy, hydroxyl group, or an oxygen atom attached by a double bond, said alkyl group being optionally substituted with one or more halogen atoms, and including optionally in its chain one or more sulfoxide functions.

6 . A method according to claim 1 , wherein the inhibitor of sterol metabolism is a compound of formula (II):

wherein;
W 3 , X 3 , Y 3 and Z 3 represent carbon, sulphur, nitrogen or oxygen atom;
n 3 and n 3′ , independently, are integer equal to 0 or 1
R 31 and R 32 , identical or different, represent a hydrogen atom, linear or branched alkyl, alkenyl, alkynyl, alkylalkenyl, alkynylalkenyl, cycloalkyl, alkylaryl, arylalkyl, arylalkenyl, arylalkynyl, heteroalkyl, heteroaryl groups, or form together a cycloalkyl group comprising 5 to 6 carbon atoms, one or two carbon atoms of said cycloalkyl group being optionally replaced by one or two heteroatoms, or one of R 31 or R 32 form together with R 39 a cycloalkyl group comprising 5 to 6 carbon atoms, one or two carbon atoms of said cycloalkyl group being possibly replaced by one or two heteroatoms, said R 31 or R 32 being optionally substituted with one or more groups independently selected from linear or branched alkyl, cycloalkyl),

alkynyl, arylalkyl, aryl, heteroaryl, hydroxyl, halogen, nitro, —COR 3a or —NR 3a R 3b group, in which R 3a and R 3b , identical or different, represent a hydrogen atom, or a linear or branched alkyl chain;
R 33 represents a hydrogen atom, a linear or branched alkyl chain, or a nitrile group;
R 34 , R 35 , R 36 , R 37 , R 38 and R 39 , identical or different, represent hydrogen or halogen atoms, or hydroxyl groups.

7 . A method according to claim 1 , wherein the inhibitor of sterol metabolism is a compound of formula (III):

wherein:
n 1 ranges from 1 to 12,
R 11 represents a hydrogen atom; a —COR 1a group, in which R 1a is a group selected from a linear or branched alkyl chain, optionally substituted with one or more groups independently selected from hydroxyl, halogen, nitro, optionally substituted benzyl groups, or optionally substituted aryl groups such as phenyl groups, said aryl groups being eventually substituted with one or more groups independently selected from halogen atoms and methyl groups;
R 12 , R 13 and R 14 , identical or different, represent a hydrogen atom; a linear or branched alkyl chain; a hydroxyl group; a —CH 2 OH group; a —COOR 1b group, in which R 1b represents a hydrogen atom, or a linear or branched alkyl chain; a —OsiR 1c R 1d R 1e group, in which R 1c , R 1d and R 1e , identical or different, represent a hydrogen atom, or a linear or branched alkyl chain; or R 12 and R 13 form together an exo methylene group;
R 15 represents a hydroxyl; a —OSiR 1c R 1d R 1e group; a —COOR 1f group, in which R 1f represents a hydrogen atom, or a linear or branched alkyl chain; a —OCOR 1g group, in which R 1g represents a linear or branched alkyl chain; or R 15 is a carbon forming an ethylenic unsaturation with the tetrahydropyranone ring,

8 . A method according to claim 1 , wherein the inhibitor of sterol metabolism is selected from the group consisting of Ethinylestradiol, Estrone, Butenafine, Mevastatin, Simvastatin, and Terbinafine.

9 . A method for producing fatty acids comprising a triggering of triacylglycerols accumulation step in microalgae as defined according to claim 1 .

10 . A method for producing biofuels comprising the following steps;
(i) a triggering of triacylglycerols accumulation step in microalgae as defined according to claim 1 , followed by (ii) an extraction step of the triacylglycerols accumulated in microalgae during step (i), and (iii) a trans-esterification step of the triacylglycerols recovered during step (ii).

11 . A method for producing pharmaceutical or cosmetic compositions comprising the following steps:
(i′) a triggering of triacylglycerols accumulation step in microalgae as defined according to claim 1 , followed by (ii′) an extraction step of the triacylglycerols accumulated in microalgae during step (i′), and (iii′) a step of adding at least one pharmaceutically or cosmetically acceptable excipient to the triacylglycerols recovered during step (ii′).

12 . A method for producing food supplements comprising the following steps:
(I″) a triggering of triacylglycerols accumulation step in microalgae as defined according to claim 1 , followed by (ii″) an extraction step of the triacylglycerols accumulated in microalgae during step (i″), and (iii″) a step of adding at least one food additive to the triacylglycerols recovered during step (ii″).

13 . The use of an inhibitor of sterol metabolism to accumulate triglycerides in microorganism.

14 . The use according to claim 13 , wherein the inhibitor of sterol metabolism is chosen from the compounds of formula (I), (II) and (III), as defined in claim 6 .

15 . The use according to claim 14 , wherein the inhibitor of sterol metabolism is selected from the group consisting of Ethinylestradiol, Estrone, Butenafine, Mevastatin, Simvastatin, Terbinafine, and combinations thereof.

16 . A method according to claim 3 , wherein the microalgae is selected from the group consisting of Nannochloropsis gaditana, Nannochloropsis oceanica , and Nannochloropsis salina.

17 . A method according to claim 6 , wherein in the compound of formula (II):

n 3 and n 3′ are equal to 1.

Assignees

• Commissariat Energie Atomique
• Centre Nat Rech Scient

Inventors

• Conte Melissa
• Dolch Lina-Juana
• Mei Coline
• Barette Caroline
• Petroutsos Dimitris
• Falconet Denis
• Jouhet Juliette
• Rebeille Fabrice
• Cintrat Jean-Christophe
• Marechal Eric

Classifications

• C10L2290/26

  Composting, fermenting or anaerobic digestion fuel components or materials from which fuels are prepared · CPC title

• C12P7/6463 Primary

  obtained from glyceride producing microorganisms, e.g. single cell oil · CPC title

• C10L2200/0469

  Renewables or materials of biological origin · CPC title

• C10L1/02

  essentially based on components consisting of carbon, hydrogen, and oxygen only · CPC title

• A23V2002/00

  Food compositions, function of food ingredients or processes for food or foodstuffs · CPC title