DE2756977A1 - PROCESS FOR THE PRODUCTION OF FATTY ACIDS - Google Patents

Description

FROM KREISLER SCHCiNWALD MEYER EISHOLD FUES VONKREISLER KELLER SELTIN ^ 5 g g 7

PATENT LAWYERS Dr.-Ing. by Kreisler 11973

Dr.-Ing. K. Schönwald, Cologne Dr.-Ing. Th. Meyer, Cologne Dr.-Ing. K. W. Eishold, Bod Soden Dr. J. F. Fues, Cologne Dipl.-Chem. Alek von Kreisler, Cologne Dipl.-Chem. Carola Keller, Cologne Dipl.-Ing. G. Setting, Cologne

5 COLOGNE 1 December 20, 1977 / Fu / Ax

DEICHMANNHAUS AT THE MAIN RAILWAY STATION

The British Petroleum Company Limited,

Britannic House, Moor Lane, London EC2Y 9BU, England

Process for obtaining
Fatty acids

Telephone: (07 21) 23 45 4V- V-4uH _: 4MMP J4> Oj3Tflegramm: Dompatent Cologne

Method of extraction
of fatty acids

The invention relates to a method for the treatment of lipid extracts, especially of microbial lipid extracts, especially for the isolation of fatty acids and; other compounds from the extracts.

Certain unicellular microorganisms, e.g. yeast / or Hydrolysates of such microorganisms have been used as protein-containing food and feed for a long time! turns. In addition to protein, most microorganisms synthesize lipids and glycerides.

A few years ago, processes were developed that make it possible to remove large numbers of single-cell microorganisms: by cultivating the microorganisms in the presence of | Hydrocarbons as a carbon substrate or from other carbon sources, e.g. oxidized hydrocarbons;

substances, e.g. methanol. ■

Processes for the production of unicellular microorganisms, e.g. yeasts or bacteria, ' using hydrocarbons or oxidized! Hydrocarbons developed as a carbon substrate. '

The hydrocarbons include methane, natural gas, normal paraffin hydrocarbons and mixtures containing normal parafinic hydrocarbons with other types of hydrocarbons contain substances, e.g. the mixtures contained in petroleum distillation cuts.

It has now been found that the unicellular microorganisms can only use certain types of hydrocarbons as a carbon source in these processes. In particular certain n-alkanes can be fully utilized. When the carbon source is recoverable

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n-alkanes, a microbial product can be produced ' that are essentially free of residual coal ' is hydrogen. This product consists essentially of proteins and lipids. The product can be used as a food and feed can be used to remove hydrocarbons without further treatment. The ones from Product extracted lipids are free of hydrocarbons. If, on the other hand, the carbon substrate is off there is a petroleum cut, which in addition to usable n-alka nen other types of hydrocarbons, in particular isoparaffinic and naphthenic hydrocarbons \ or even contains aromatic hydrocarbons, can ι the latter does not "be utilized by the microorganism, so that the microbes product with the non-recycled I Is contaminated with hydrocarbons. If the product is to be used as food or feed,

the hydrocarbons must be removed. Extrak!

tion process for removing contaminating coals ^

Hydrogen from such microorganism products are j

known. In these processes, the product I. with a suitable solvent, for example a j

Alcohol, e.g. isopropanol or ethanol. It is very difficult to extract lipids from hydrocarbons with the usual extraction methods to remove contaminants cleaning hydrocarbons from microorganisms * to separate products. As a result, the extracts consist of a mixture of lipids and very different ones Hydrocarbon types. The hydrocarbons can be in be present in significant quantities. When the microorganism mus using a source of carbon Hydrocarbon, which can be completely utilized by the microorganism, has been cultivated, can lipids extracted from the microorganism product free of hydrocarbons or in a small amount contaminated with unused hydrocarbons

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On the other hand, when the carbon substrate is a petroleum hydrocarbon is used, the unusable hydrocarbons such as naphtha, a crude oil or gas oil cut contains, the microorganism product or lipids extracted from the microorganism are usually included contaminated with hydrocarbons. In addition, the extract can contain various compounds from the partial hydrolysis of proteins, e.g. amino acids from the microorganism and impurities from the extraction process reagents used come from, for example solvents, e.g. alcohols such as ethanol or isopropanol, contain.

It has now been found that the length of the carbon chains present in the lipids synthesized by microorganisms cultivated using hydrocarbons as a carbon substrate depends in part on the length of the carbon chains present in the hydrocarbon substrate. Further, it is possible, the fatty acid component of the lipid substrates, the length of the carbon chain j by selecting the carbon chain length of the hydrocarbon \ influence was found. Furthermore, if the hydrocarbon, substance substrate from a mixture of hydrocarbons ι

consists of petroleum, the carbon chains with straight and j Contain odd numbers of carbon atoms, contain! ten the fatty acids produced by the microorganisms

synthesized lipids are isolated, also even ί and odd numbers of carbon atoms. It is therefore j possible to provide a method for the simultaneous production \ microbial protein and from fatty acids with specific carbon chain lengths.

As used herein, "lipid extract" is a lipid extract of any origin, in particular that from microorganisms with the help of an extraction process Complex mixture of lipids obtained to understand that

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with various substances, especially hydrocarbons ■ Solvents, e.g. monohydric alcohols, free Fatty acids, polyhydric alcohols like glycerin, amino alcohols and amines can be contaminated.

Those of unicellular microorganisms, especially of

Lipids synthesized by yeast consist mainly of a mixture of glycerophospholipids and triglycerides, but can contain free fatty acids. For example, 'had a lipid extract by extraction with ^a: was use of a gas oil as a carbon substrate cultured yeast, the following composition (as solvent was isopropanol used in the extraction):

Gas oil 15% (approx.) Free fatty acids 3% " Triglycerides 25% Glycerophospholipids 45% "j Solvent (isopropanol) 2% "! Various connections'

(e.g. amino acids and water) 10% "I.

A lipid extract from yeast that is grown in the presence only of usable n-alkanes as a carbon source had the following composition:

Free fatty acids 2% (approx.)

5 triglycerides 32%

Glycerophospholipids 55% " Solvent (isopropanol) 1% " Different connections

(e.g. water) 10% "

The invention relates to an improved method for the isolation of fatty acids and other compounds from lipid extracts, in particular a process for the isolation of fatty acids that are either free of unsaponifiable Material are or this in relatively lower

Concentration contained, from lipid extracts of microbes.

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The invention accordingly relates to the isolation of fatty acids and other compounds from lipid extracts directed a process, which is characterized in that the lipid extract in the liquid phase in the presence a monovalent metal hydroxide or a mixture of monovalent metal hydroxides and neutralized saponified and thereby forms a saponified extract that soaps fatty acids and unsaponifiable material contains, the saponified extract subjected to a distillation treatment in which the temperature and the Pressure regulates so that the soaps are kept in the liquid state, and on the one hand a substantial ι a distillate consisting of unsaponifiable material and, on the other hand, an anhydrous residue is separated off, which consists essentially of soaps of fatty acids, which split off fatty acids from the soaps and thereby one Forms reaction mixture containing the fatty acids, and then isolates the fatty acids from the reaction mixture.

Before neutralization and saponification with the monovalent metal hydroxide, the lipid extract can be subjected to hydrolysis to release fatty acids and other compounds such as glycerides and phosphates. The previous one Hydrolysis accelerates the subsequent reactions. The hydrolysis can be carried out by known methods, e.g. according to the Twitchell process, in which an acid j

catalyst, e.g., an alkylarylsulfonic acid, used j can be carried out. This hydrolysis is carried out at normal pressure. It is also possible to hydrolysis under pressure in the presence or absence of a j

Catalyst, e.g. zinc oxide. At the most expedient-; The reaction should be carried out until at least 95% of the fatty acids are released from the lipids, have been. However, the degree of hydrolysis can also be less than 95% if the target is at a distance of phosphorus is limited. The response can be quick

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run and does not require hHufig even at relatively \ moderate pressures the use of a catalyst. The presence of glycerophospholipids, which are good emulsifiers, in the lipid extracts favors the reaction.

The hydrolyzed or untreated lipid extracts are in the presence of a monovalent metal hydroxide or a _; Mixture of monovalent metal hydroxides neutralized and saponified. Examples of suitable hydroxides are sodium and potassium hydroxide. The reaction takes place in the liquid phase. Water can be present. Most conveniently, the reaction can be carried out at an elevated temperature. The liquid phase can be maintained by working under excess pressure. The reaction at elevated temperature can be carried out under pressure in an autoclave. The pressure can be in the range from 5 to 20 bar. Most expediently, the monovalent metal hydroxide or the mixture of monovalent metal hydroxides is chosen so that in the saponified extract i a eutectic mixture of soaps of fatty acids with |

the lowest possible melting point is present. Potassium hydroxide or a mixture of potassium hydroxide and sodium j hydroxyd can be used for this purpose.

The amount of the monovalent metal hydroxide or the mixture of monovalent metal hydroxides can thus be calculated be that upon completion of the neutralization and saponification reaction a slight excess of the hydroxide is present in the saponified extract, so that the extract dispersed in water has a pH of about 8.5 in the alkaline Area, i.e. when it reacts with phenolphthalein, the dispersion turns pale pink in color.

The lipid extracts can contain sulfur-containing impurities. These connections can be the Interfere with reactions of the method according to the invention. The sulfur-containing impurities can be added

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of a hydroxide or salt of a heavy detail that is reactive with the sulfur-containing impurities, can be removed. For example, black lead or Sodium plumbite, which can be added to the sodium hydroxide, can be used. The heavy metal salt or hydroxide can be added at any stage in the process. i

The saponified extract contains alkali soaps present in the lipid extract fatty acids and unsaponifiable material such as alkali metal phosphates, hydrocarbons, glycerol, amino alcohols, trimethylamine, solvent, for example ethanol ^or, isopropanol, and heavy metal salts, which were for the removal j of the sulfur-containing impurities optionally added.

The next stage of the process is the distillation of the saponified extract, on the one hand a distillate, the j

essentially of unsaponifiable material, and j on the other hand a water-free residue, which essentially consists of soaps of the fatty acids from the lipid extract and non-distillable substances \ be separated. The distillate can be unsaponifiable material such as; Contain hydrocarbons, solvents, glycerin, amines, amino alcohols and traces of heavy ketones that; may have been formed as a result of the thermal stress (pyrogenatlon) of the soaps. The anhydrous residue consists essentially of alkali metal soaps, but can also contain alkali phosphates and other non-distillable substances.

The temperature and pressure of the distillation must be: regulated so that those present in the saponified extract Soaps throughout the removal of the distill- j

material remain in the liquid state, which facilitates the volatilization of the distillable material will. The distillation can take place in any distillation

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equipment, e.g. retorts or columns, carried out ' will. Απ most appropriate the temperature should be like this: be chosen so that no significant thermal decomposition of the soaps takes place. The heating should be done in such a way that local overheating, the pyrolysis create of soaps or available glycerin; could be prevented. A working method is suitable, j in which a heat transfer medium or water cycle under ι Pressure possibly supplemented by a bath of molten | zenem metal is used, for example of lead or a lead 'alloy. The distillation temperature and; the average temperature at the bottom of the distillation apparatus depends on the one hand on the type and on the molecular weight of the fatty acids present which make up the j

Affect the melting point of the soaps, and on the other hand

on the type and distillation curve of the unsaponifiable material which it is desired to remove. The ^: temperature can vary with each type of lipid extract depending on the compounds present. The pressure must be so j be set that the in the saponified extract from the beginning-j which soaps at the distillation temperature during the j remain in the liquid state throughout the removal of distillable material. The j last part of the distillable material under reducing-j must be removed. The pressure can range from 0.1 to 10 mm Hg. It is also possible to use water vapor or passing an inert gas through the extract to volatilize the last traces of distillable material.

If the lipid from a microorganism extracted wordet, which has been obtained from a fermentation using a in the range of 300 ° to 385 ° C-boiling gas oil fraction as a carbon source, the distillation temperature in the range of 140 ° can be up to 200 ⁰ C and the pressure will be about 10 mm Hg. The final pressure by which the last traces of unsaponifiable material are removed

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- ta -

are, can be reduced, while the anhydrous residue, which consists of molten soap substantially is maintained at a temperature of 38O ⁰ C at 1 mm Hg. Under these conditions, the hydrocarbons, glycerine and the various amino alcohols originally contained in the saponified extract can be removed under reduced pressure without thermal decomposition of the soaps. It is also possible during ^: the distillation, alcohols that are present! can, to separate or at least to obtain fractions that are richer in an alcohol by breaking down the fractions at very specific temperature intervals

will. \

The acids can be split off from the soaps that are present in the residue remaining after the unsaponifiable material has been distilled off by treating the residue with a strong acid, for example with a sulfuric acid or phosphoric acid solution. Conveniently at * of the soap-containing geschmol-, zene residue of a heated solution of the acid is added. The residue can be diluted with water before treatment with the acid. Preferably the ■

ι reaction carried out so that essentially all fat | acids are split off from the soaps. The amount of acid j is chosen so that the pH of the reaction mixture containing the fatty acids and by the treatment for Cleavage of the fatty acids from the soaps is less than 7, in particular in the range from 3 to 4J and the color of methyl orange is changed. By! Movement, for example, mechanically or with Water vapor or a gas applied to the residue will facilitate the reaction. The mixture obtained after the fatty acids have been split off from the soaps contains fatty acids and alkali metal salts strong acids.

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- Λ $

The fatty acids can be isolated from the reaction mixture by known methods. For example, the mixture may be decanted with water, whereby an aqueous supernatant or an upper phase containing the fatty acids, wird.Die obtained in this manner insulated fatty acids most conveniently \ 1.0% or less unsaponifiable substances. A content of unsaponifiable substances in the range from 0.5 to 0.1% is particularly expedient. The individual fatty acids can be separated from the supernatant liquid or upper phase by distillation, preferably under reduced pressure and preferably after washing with water, fatty acids with different chain lengths and degrees of unsaturation being obtained. It is also possible to separate the individual acids according to known separation processes according to the length of the carbon chains in the acids or according to the melting point.

When the lipid extract is derived from microorganisms \ from fermentations using one of a been obtained in the range of> 300 to 385 ° C boiling gas oil hydrocarbon as a carbon substrate, according to 'the method of the invention have from the extract j fatty acids isolated a length of the carbon chain in Range from 15 to 18, with a relatively large proportion having a chain length of 17. The fatty acids with 15 or 16 carbon atoms in the carbon chain are mainly saturated, while the C ₁₇ and C 8 fatty acids are essentially unsaturated, with a considerable proportion being polyunsaturated. Fatty acids derived from Lipidextrak _r are ten isolated which ;, which have been obtained in fermentations using n-paraffins as a carbon source, which are identical to the n-paraffins in the used as the gas oil carbon substrate, derived from microorganisms are the Fatty acids from the microorganisms grown using gas oil.

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The fraction of the reaction mixture that remains after the isolation of the fatty acids contains alkali metal salts of the strong acids or the acids as such which are used to split off the fatty acids from the soaps, and can contain unsaponifiable substances. If the pH of the fraction is in the alkaline range, the salts of the acids can be isolated by known methods for the recovery of these salts. If the pH of the fraction is in the acidic range, it can be treated with an alkaline earth metal, for example calcium hydroxide, in order to precipitate the alkaline earth salts of the acids. These salts can then be separated off by known methods. When phosphoric acid is used as a strong acid! the salts separated off consist exclusively of phosphates. On the other hand, the lipid _extracts: normally contain phosphorus, an acid other than phosphoric acid as a strong acid for cleavage of the soaps is obtained a mixture of phosphates and '■ salts of other acid such as sulfates, in use.

The unsaponifiable material obtained in the distillation of the saponified extract can be water-soluble and water-insoluble compounds such as hydrocarbons, |

Contain amino alcohols, glycerine, triethylamine and alcohols. These compounds can be isolated by first the distillate is washed with water, j being a fraction containing the water-soluble compounds, e.g. which contains amino alcohols, glycerol, triethylamine and alcohols, I, and a fraction which is insoluble in water Contains compounds, e.g. the hydrocarbons

will hold. ι

If the compounds that are insoluble in water are hydrocarbons, they can be removed by drying the fraction containing the compounds insoluble in water, separated and, if necessary, at -35, cleaned by steam distillation, for example

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the. The process used to recover the in the;

Fraction of existing water-soluble compounds' applied varies depending on the type of connections. For example, methods such as

fractional distillation or rectification, the ^;

wholly or partly under reduced pressure i

leads can be to compounds such as alcohols, amino .

to obtain alcohols, choline and glycerine. The remaining after the \ distillation or rectification back

can stand another distillation, e.g. a Steam distillation at an alkaline pH Area to be subjected to compounds such as amines and in particular triethylamine and amino alcohols, e.g. Ethanolamine to win.

In addition to the isolation of the fatty acids from the lipid extracts, the method according to the invention enables thus the isolation of compounds such as hydrocarbons, e.g. gas oils and n-paraffins, solvents, e.g. alcohols such as isopropanol and others through the Cleavage of lipids formed alcohols, e.g. glycerine, Amino alcohols, e.g. ethanolamine, amines and phosphate ions from the extracts.

The process according to the invention is further illustrated by the following examples.

example 1

A microbial lipid extract was obtained from a hydrocarbon-utilizing strain of the yeast Candida tropicalis obtained from fermentation the yeast in the presence of a gas oil boiling in the range of 300 ° to 385 ° C serving as a carbon source was cultivated. The extract had the following properties:

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Content of hydrocarbons and

other unsaponifiable material 14.5 wt .-% content of free and bound

Fatty acids 49.5 "

Phosphorus content 2.2 "

Acid number 42.7

The extract was subjected to limited hydrolysis by standing for one hour with water in the absence of a catalyst at a temperature of about 212 ° C under a pressure of about 20 atm. was treated to reduce the phosphorus content and release fatty acids from the i lipids. The hydrolyzed extract had _; the following ^properties:

Water content 1.5% by weight;

Unsaponifiable material 15.5 "

Phosphorus content less than 0.01 "

Acid number 103.2

Saponification number 143 '

1000 kg of the hydrolyzed extract were in the liquid phase in an autoclave at 150 ° C. under a pressure j of 5 atm. 1 hour in the presence of 357 kg of 30% | Sodium hydroxide solution neutralized and saponified. The saponified extract obtained here, which is a mixture of; Soaps from fatty acids and unsaponifiable material de- | held, had a pH of 8.5. The saponified ex! tract was fed in the liquid state to a distillation apparatus, where it was initially at normal pressure and was finally distilled under a reduced pressure of 2 mm Hg, with live steam being blown in.

Here, on the one hand, 805 kg of an anhydrous residue, which essentially consists of melted soaps of fatty acids and had a temperature of about 385 ° C, and on the other hand 552 kg of distillate, which was 224 kg contained unsaponifiable material. The soaps were in the

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kept liquid state.

The anhydrous residue of molten soaps and fatty acids was added to a 10% aqueous sulfuric acid solution. The mixture was at 100 ° C on The reflux condenser is heated to split off the fatty acids from the soap. The anhydrous acid was in an amount of 133 kg used. The fatty acids were removed from the reaction mixture obtained by neutral washing isolated with water, being an aqueous solution containing the containing crude fatty acids. The watery Solution of the fatty acids was distilled under reduced pressure to purify the individual acids and to separate. The distillation resulted in 530 kg of fatty acids together with 153 kg of a soft pitch which was im consisted essentially of polymerizing fatty acids. The fatty acids and the bad luck had the following metrics:

Fatty acids

Acid number 211

Saponification Number 212

Iodine number 64.2

Content of unsaponifiable substances 0.4% by weight

bad luck

Acid number 156 -

Saponification number 168 Flow point (ring and ball) 26 ° C

The pitch can be used, for example, as an emulsifier for bitumen. If desired, the during the Purification of the fatty acids, the amount of pitch formed can be reduced by blowing in steam during the distillation. The fatty acids thus obtained were analyzed by gas chromatography. The fatty acids had the key figures given in the table below.

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- 10

ίο

15th

20th

25th

ί 30

C number the number of 0
1 Approximately 2756977
Proportion,% by weight straight Chains Double bin
fertilize ^C 14
^C 15 0
0 , 2 0.2
i. 2.0 ^C 14

'15

'16

'16

Ί7

'17

• 17th

'18

'18

Ί8

'18

'19

Ί9

Not determined

0.1
8.8

5.3

14.1

unsaturated 0.5

52.2

28.8

1.8

0.9

1.8 100.0

The following types of acids were present: Saturated fatty acids about 29% by weight

Monounsaturated fatty acids "50" Diunsaturated fatty acids "16" Triunsaturated fatty acids "4"

The distillate containing the unsaponifiable material separated from the saponified extract was as follows

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Composition: hydrocarbon content

Glycerine content Amino alcohol content

13% by weight of the lipid extract

9.0 wt% 1.5

5 Example 2

A microbial lipid extract was made from a hydrocarbon utilizing strain of the yeast Candida tropicalis obtained from fermentation in which the yeast in the presence of a carbon source serving petroleum fraction boiling in the range from 280 to 360 ° C had been cultivated. The extract had the following properties:

Hydrocarbon content Free fatty acid content 15 Glyceride content Glycerophospholipid content isopropanol

Various components (amino acids, water)

The extract was in the liquid phase in an autoclave in the presence of a 50% potassium hydroxide solution, to which 0.1% black lead had been added, neutralized and saponified. The reaction mixture became a Held at a temperature of 160 ° C. for an hour to obtain a saponified extract, the soaps of Contained fatty acids and unsaponifiable material.

The saponified extract was distilled under the temperature and pressure conditions mentioned in Example 1, being on the one hand an anhydrous residue consisting essentially of melted soaps of fatty acids and 6 wt .-% consisted of phosphates, and on the other hand, a distillate, which contained unsaponifiable material,

12th Wt% 35 Il 25th Il 45 H 2 , 0 " 13th Il

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12th approximately 8th ti 5 If 1

were holding. The fatty acids were removed from the anhydrous residue in the manner described in Example 1: split off and isolated. The isolated mixture of fatty acids had an acid number after washing with water of 215 and contained 0.5% by weight unsaponifiables. 53% by weight of fatty acids, based on the weight of the Lipid extract were isolated. i

The distillate containing the unsaponifiable material had the following composition:

% By weight, based on

the weight of the; Lipid extract

Hydrocarbon content
Glycerol content

Amino alcohol content
Isopropanol content

Example 3

A lipid extract was obtained from a hydrocarbon-utilizing strain of the yeast Candida tropicalis, which came from a fermentation in which the yeast was a serving as a carbon source, cultured in the presence of in the range of 250 ° to 294 ⁰ C boiling mixture of n-alkanes. 90% of the alkanes had carbon numbers in the range from C ^ ₄ to C ^ ₇ . The extract was

obtained from the yeast by extraction using isopropanol. The extract had a hydrocarbon content of less than 0.05% by weight. It was processed in the manner described in Example 1, using a mixture of crude fatty acids having an acid number of 210 | and contained less than 0.1 Gev /, -% unsaponifiable substances, was isolated. 55% by weight of fatty acids, based on!

based on the weight of the lipid extract were isolated. I.

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Claims (22)

Claims 1. A method for isolating fatty acids and other * compounds from lipid extracts, characterized in that the lipid extract is neutralized and saponified in the liquid phase in the presence of a monovalent metal hydroxide or a mixture of monovalent metal hydroxides and thereby a saponified extract is formed, the soaps of fatty acids and unsaponifiable material contains, subjecting the saponified extract of a distillation treatment, in which it regulates the temperature and _{the pressure so that the soap in liquid state; the fatty acids are maintained, and in this case on the one hand (in the essential 2hen from unsaponifiable material j existing distillate and the other part separates an anhydrous residue, which essentially consists of soaps of fatty acids. 'separates from the soap, thereby forming a reaction mixture / the the Contains fatty acids, and then the fatty acids are isolated from the reaction mixture j. J 2. The method according to claim 1, characterized in that the lipid extract at elevated temperature and | increased pressure neutralizes and saponifies. j 3. The method according to claim 1 or 2, characterized in that the lipid extract is in the presence of water neutralized and saponified. 4. The method according to claim 1 to 3, characterized in that that the lipid extract is neutralized and saponified at a pressure in the range from 5 to 20 bar. 5. The method according to claim 1 to 4, characterized in that the monovalent metal hydroxide or the mixture of monovalent metal hydroxides so that in the saponified extract a eutectic mixture of soaps of Fatty acids with the lowest possible melting point is formed. 809826/0858 ORIGINAL INSPECTED 6. The method according to claim 1 to 5, characterized in that the monovalent metal hydroxide or the mixture of
monovalent metal hydroxides for neutralization and
Saponification of the lipid extract in such an amount
is used that the hydroxide in the saponified extract is present in excess, so that the extract, when it is in
Water is dispersed, a pH in alkaline
Area has. 7. The method according to claim 1 to 6, characterized in that the lipid extract is completely saponified. 8. The method according to claim 1 to 7, characterized in that roan the lipid extract before neutralization and
Saponification hydrolyzes and thereby releases fatty acids from the lipids. 9. The method according to claim 1 to 8, characterized in that the saponified extract is at a temperature
distilled, in which no significant thermal 'decomposition of the soaps takes place. : 10. The method according to claim 1 to 9, characterized in that the saponified extract at a temperature in
Range from 140 ° to 200 ⁰ C and a pressure of 10 mm Hg j distilled. 11. The method according to claim 1 to 10, characterized ^ that the pressure under which the saponified extract is distilled during the removal of the last traces of distillable: non-saponifiable material, in the range _j from 0.1 to 10 mm Hg. [ 12. The method according to claim 1 to 11, characterized in that! that a hydroxide or a salt of a heavy metal, which | with the sulphurous impurities in the lipid | extract reacts, is present. ' 13. The method according to claim 1 to 12, characterized in that: that the fatty acids by treating the anhydrous j residue with a strong acid from the soaps i 809826/0858 splits off. ■ 14. The method according to claim 1 to 13, characterized in that that phosphoric acid is used as the strong acid. 15. The method according to claim 1 to 14, characterized in that that the pH of the reaction mixture containing the fatty acids is kept at less than 7. : 16. The method according to claim 1 to 15, characterized in that the fatty acids from the reaction mixture by decanting with water to form an aqueous liquid supernatant or an upper phase containing the fatty acids contains, separates. 17. The method according to claim 16, characterized in that the fatty acids from the liquid supernatant or from the ' upper phase by distillation under reduced pressure. separates and hereby separated fatty acids with different Chain length and varying degrees of; Preserves unsaturation. i 18. The method according to claim 1 to 17, characterized in that ' that you get the distillate, the unsaponifiable material the saponified extract contains, washes with water and thereby a fraction that contains water-soluble compounds and a fraction containing compounds insoluble in water is isolated. 19. The method according to claim 18, characterized in that the fraction containing the soluble compounds subjected to a distillation and thereby wins the water-soluble compounds. 20. The method according to claim 1 to 19, characterized in that the lipid extract is a microbial lipid extract, obtained by extracting a microorganism with a solvent for the lipid. 809826/085 « 21. The method according to claim 20, characterized in that the microorganism is one on hydrocarbons grown yeast is. 22. Fatty acids isolated by the method according to claims 1 to 21. 809826/0858