JP2023006709A - Microalgae growth promoter - Google Patents

Abstract

To provide a microalgae growth promoter.SOLUTION: A microalgae growth promoter contains at least one compound selected from (1) oxo fatty acid or a derivative thereof or a salt thereof or (2) a hydroxylated fatty acid or a derivative thereof or a salt thereof.SELECTED DRAWING: None

Description

The present invention relates to microalgae growth promoters.

Conventionally, microalgae are grown, lipids that are raw materials for fuel, feed, health foods, etc. are produced and stored in the cells of microalgae, or valuables such as proteins and vitamins are produced and stored, and the stored valuables are used. It is used as fuel and food.

Patent Document 1 describes a method for culturing heterotrophic microalgae using a medium containing POME.

However, in Patent Document 1, a waste liquid called POME from a palm oil refinery must be used, and importing such a waste liquid from Southeast Asia is undesirable from the viewpoint of cost and stability of raw material supply. According to Non-Patent Document 1, POME contains 33% oleic acid (C18: unsaturated bond 1), 31% palmitic acid (C16: unsaturated bond 0), linoleic acid (C18: unsaturated bond 2 ) contains 9%, and the inventors have found that such linear saturated and unsaturated fatty acids alone are not effective as a growth promoter for microalgae.

WO2020/026794

Environmental Engineering Research. Vol. 40, 2003

SUMMARY OF THE INVENTION In view of the problems described above, an object of the present invention is to provide a microalgae growth promoter capable of efficiently growing algae.

The present invention relates to a microalgae growth promoter containing at least one compound selected from (1) oxo fatty acid or its derivative or its salt, or (2) hydroxylated fatty acid or its derivative or its salt.

It is preferable that the microalgae growth promoter further contains an unsaturated fatty acid (excluding the oxo fatty acid and the hydroxylated fatty acid).

A growth promoter for microalgae, wherein the unsaturated fatty acid is an unsaturated fatty acid having 10 to 20 carbon atoms is preferred.

Growth promotion of microalgae, wherein the unsaturated fatty acid is an unsaturated fatty acid selected from the monovalent or polyunsaturated fatty acid group consisting of oleic acid, linoleic acid, α-linolenic acid, γ-linolenic acid, arachidonic acid, etc. agents are preferred.

Preferably, the unsaturated fatty acid is linoleic acid.

The oxo fatty acid or derivative or salt thereof of the formula:
HOOC-(R ¹ )-CH=CH-C(=O)-R ² (I)
(In the formula,
R ¹ : a linear or branched, saturated or unsaturated hydrocarbon group containing 6 to 12 carbon atoms;
R ² : an alkyl group having 2 to 8 carbon atoms, which may contain one or more branches and/or double bonds)
A microalgae growth promoter that is an oxo fatty acid having the structural formula or a derivative thereof or a salt thereof is preferred.

A growth promoter for microalgae, wherein the oxo fatty acid is an oxo fatty acid in which the hydrocarbon group of R ¹ of the oxo fatty acid has 8 to 10 carbon atoms and the alkyl group of R ² has 4 to 6 carbon atoms. preferable.

of microalgae, wherein the oxo-fatty acid is an oxo-fatty acid in which R ¹ of the oxo-fatty acid contains a double bond forming a conjugated double bond with the double bond between the α and β carbons of the carbonyl group in formula (I) Growth promoters are preferred.

Growth promoter for microalgae, wherein the oxo fatty acid is an oxo fatty acid in which R ¹ of the oxo fatty acid is a linear or branched hydrocarbon group having 9 carbon atoms and R ² is an alkyl group having 5 carbon atoms. is preferred.

Preferably, the oxo fatty acid is ketooctadecadienoic acid.

Preferably, the oxo fatty acid is 13-oxo-9,11-octadecadienoic acid.

The hydroxylated fatty acid or derivative thereof or salt thereof is represented by the following formulas (II) and/or (III):
HOOC-(R ³ )-CH(OH)-CH(OH)-CH=CH-CH(OH)-R ⁴ (II)
HOOC-(R ³ )-CH(OH)-CH=CH-CH(OH)-CH(OH)-R ⁴ (III)
(In the formula,
R ³ is a straight-chain or branched hydrocarbon group having 4 to 12 carbon atoms, which may contain one or more double bonds and/or OH groups, The position of the double bond is not limited if it contains
R ⁴ is a straight-chain or branched hydrocarbon group having 2 to 8 carbon atoms and optionally containing one or more double bonds and/or OH groups, The position of the double bond is not limited if it contains
A microalgae growth promoter that is a hydroxylated fatty acid having the structural formula or a derivative thereof or a salt thereof is preferred.

A microalgae growth promoter in which said hydroxylated fatty acid has 6 to 8 carbon atoms in the hydrocarbon group of R ³ and 4 to 6 carbon atoms in the hydrocarbon group of R ⁴ is preferred. .

In the hydroxylated fatty acid, R ³ has a structure of -(CH ₂ ) _n - (n is an integer of 4 to 12), and R ⁴ is C _n H _2n+1 - (n is an integer of 2 to 8). Microalgae growth promoters that are of a certain integer) structure are preferred.

In the fatty acid hydroxide, R ³ is an alkylene group having 7 carbon atoms (--(CH ₂ ) ₇ --), and R ⁴ is an alkyl group having 5 carbon atoms (CH ₃ CH ₂ CH ₂ CH ₂ CH ₂ -- ) is preferred.

The microalgae growth promoter, wherein the hydroxylated fatty acid is hydroxyoctadecaenoic acid, is preferred.

The microalgae growth promoter is preferred, wherein the hydroxylated fatty acid is 9,10,13-trihydroxy-11-octadecaenoic acid.

The microalgae growth promoter is preferred, wherein the hydroxylated fatty acid is 9,12,13-trihydroxy-10-octadecaenoic acid.

Incidentally, "octadecaenoic acid" is a commonly used notation (for example, JP-A-3-14539), and the above-mentioned "9,10,13-trihydroxy-11-octadecaenoic acid" is "9,10, 13-trihydroxyoctadeca-11-enoic acid" or "9,10,13-trihydroxy-11-octadecenoic acid". Similarly, the above "9,12,13-trihydroxy-10-octadecaenoic acid" is referred to as "9,12,13-trihydroxyoctadeca-10-enoic acid" or "9,12,13-trihydroxy- Also called 10-octadecenoic acid. In addition, in the examples, the notation of the manufacturer is also written in parentheses. Also, the above description applies to all "octadecaenoic acid" used in the specification, claims and abstract.

The structural formula of "9,10,13-trihydroxy-11-octadecaenoic acid" is represented by the following structural formula (1).

The structural formula of "9,12,13-trihydroxy-10-octadecaenoic acid" is represented by the following structural formula (2).

The ratio of the at least one compound selected from the oxo fatty acid or its derivative or its salt and the hydroxylated fatty acid or its derivative or its salt to the unsaturated fatty acid is 10% to 90% by weight. A growth promoter for microalgae containing the unsaturated fatty acid is preferable so that

The oxo fatty acid and hydroxylated fatty acid derivatives are preferably esters of oxo fatty acid and hydroxylated fatty acid, respectively. As the salt of the oxo fatty acid and hydroxylated fatty acid, as will be described later, salts such as sodium salt, potassium salt and ammonium salt can be used.

The microalgae growth promoter is preferably used as a medium for microalgae.

It is desirable that the microalgae growth promoter is used for at least one species selected from Euglena, Chlorella, and Spirulina.

Furthermore, it is desirable that the microalgae growth promoter contains at least one or more selected from potassium ions, carbonate ions, phosphate ions, calcium ions, and sodium ions.

The microalgae growth promoter of the present invention can efficiently grow microalgae.

The growth promoter for microalgae of the present invention contains at least one compound selected from (1) oxo fatty acid or its derivative or its salt, or (2) hydroxylated fatty acid or its derivative or its salt as a growth promoting component. including. Such oxo fatty acids and hydroxylated fatty acids are more effective in promoting the growth of microalgae than linear saturated fatty acids and unsaturated fatty acids that do not have a carbonyl structure other than a carboxyl group or hydroxyl groups.

In the present invention, the term "microalgae" refers to organisms that are unicellular organisms that mainly exist in water and are broadly classified as algae, and many of them carry out photosynthesis. Microalgae can include those classified as green algae, yellow flagellates, diatoms, dinoflagellates, unicellular eukaryotic algae, freshwater unicellular green algae, and cyanobacteria. In general, it is microscopic algae, and more specifically, it refers to algae having a cell size of about 1 to 500 μm in diameter when observed with an optical microscope. Microalgae also include those in which a plurality of cells form colonies. The microalgae growth promoter of the present invention can be used to promote the growth of any microalgae known to those skilled in the art, and the type of microalgae to which it is applied is not particularly limited.

The microalgae growth promoter of the present invention contains at least one compound selected from the above-described active ingredients, that is, oxo fatty acids or derivatives thereof or salts thereof and hydroxylated fatty acids or derivatives thereof or salts thereof. May contain saturated fatty acids. Oxo fatty acids and hydroxylated fatty acids are excluded from the unsaturated fatty acids of the present invention. The unsaturated fatty acid that can be contained in the microalgae growth promoter of the present invention has the effect of promoting the absorption of the oxo fatty acid and the hydroxylated fatty acid into the microalgae. This is because the cell membrane of microalgae is composed of lipids, and the oxo fatty acid and the hydroxylated fatty acid are more likely to permeate the cell membrane when the unsaturated fatty acid is contained.

The oxo fatty acid, derivative thereof, or salt thereof of the present invention has the following formula:
HOOC-(R ¹ )-CH=CH-C(=O)-R ² (I)
(In the formula,
R ¹ : a linear or branched, saturated or unsaturated hydrocarbon group containing 6 to 12 carbon atoms and R ² : an alkyl group having 2 to 8 carbon atoms, and one or more may contain branches and/or double bonds of
An oxo fatty acid having the structural formula or a derivative thereof or a salt thereof can be preferably used.

In one embodiment of the present invention, the hydrocarbon group of R ¹ in the oxo fatty acid has 8 to 10 carbon atoms, and the alkyl group of R ² has 4 to 6 carbon atoms. In another embodiment, R ¹ in the oxo fatty acid contains a double bond that forms a conjugated double bond with the double bond between the α and β carbons of the carbonyl group in formula (I). Furthermore, in another embodiment, R ¹ in the oxo fatty acid is preferably a linear or branched hydrocarbon group with 9 carbon atoms, and R ² is preferably an alkyl group with 5 carbon atoms.

The oxo fatty acid of the present invention specifically includes ketooctadecadienoic acid. For example, ketooctadecadienoic acids include, but are not limited to, 9-oxo-10,12-octadecadienoic acid (9-oxoODA), 13-oxo-9,11-octadecadienoic acid (13-oxoODA), 5-oxo-6,8-octadecadienoic acid, 6-oxo-9,12-octadecadienoic acid, 8-oxo-9,12-octadecadienoic acid, 10-oxo-8 ,12-octadecadienoic acid, 11-oxo-9,12-octadecadienoic acid, 12-oxo-9,13-octadecadienoic acid and 14-oxo-9,12-octadecadienoic acid and their isomers A body etc. are mentioned.

Esters are desirable as derivatives of oxo fatty acids. Esters of oxo fatty acids of the present invention include, but are not limited to, methyl esters, ethyl esters, propyl esters, butyl esters, pentyl esters, isopentyl esters, octyl esters, and the like. Examples of salts of oxo fatty acids include ammonium salts such as alkylammonium salts such as ammonium salts and tetramethylammonium salts, alkaline earth metal salts such as calcium salts and magnesium salts, and sodium salts, lithium salts and potassium salts. and metal salts such as alkali metal salts such as cobalt salts and manganese salts.

The hydroxylated fatty acid or derivative thereof or salt thereof of the present invention includes the following formulas (II) and/or (III)
HOOC-(R ³ )-CH(OH)-CH(OH)-CH=CH-CH(OH)-R ⁴ (II)
HOOC-(R ³ )-CH(OH)-CH=CH-CH(OH)-CH(OH)-R ⁴ (III)
(In the formula,
R ³ is a straight-chain or branched hydrocarbon group having 4 to 12 carbon atoms, which may contain one or more double bonds and/or OH groups, The position of the double bond is not limited if it contains
R ⁴ is a straight-chain or branched hydrocarbon group having 2 to 8 carbon atoms and optionally containing one or more double bonds and/or OH groups, The position of the double bond is not limited if it contains
A hydroxylated fatty acid having the structural formula or a derivative thereof or a salt thereof can be preferably used.

In one embodiment of the invention, the R ³ hydrocarbon group in the hydroxylated fatty acid has 6 to 8 carbon atoms and the R ⁴ hydrocarbon group has 4 to 6 carbon atoms. In another embodiment, R ³ in the hydroxylated fatty acid has the structure —(CH ₂ ) _n — (n is an integer of 4 to 12), and R ⁴ is C _n H _2n+1 - (n is an integer from 2 to 8). Furthermore, in another embodiment, R ³ in the hydroxylated fatty acid is an alkylene group having 7 carbon atoms (--(CH ₂ ) ₇ --), and R ⁴ is an alkyl group having 5 carbon atoms (CH ₃ CH ₂ CH ₂ CH ₂ CH ₂ --) is preferred.

The hydroxylated fatty acid of the present invention specifically includes hydroxyoctadecaenoic acid. For example, hydroxyoctadecaenoic acid includes, but is not limited to, 9,10,13-trihydroxy-11-octadecaenoic acid and/or 9,12,13-trihydroxy-10-octadecaenoic acid and isomers thereof are included.

Esters are desirable as derivatives of hydroxylated fatty acids. Esters of hydroxylated fatty acids of the present invention include, but are not limited to, methyl esters, ethyl esters, propyl esters, butyl esters, pentyl esters, isopentyl esters, octyl esters, and the like. Examples of salts of hydroxylated fatty acids include ammonium salts such as alkylammonium salts such as ammonium salts and tetramethylammonium salts, alkaline earth metal salts such as calcium salts and magnesium salts, and sodium salts, lithium salts and potassium salts. Alkali metal salts such as salts, metal salts such as cobalt salts, manganese salts, and the like are included.

For example, the microalgae growth promoter of the present invention may contain at least one compound selected from ketooctadecadienoic acid, derivatives thereof, or salts thereof and hydroxyoctadecaenoic acid, derivatives thereof, or salts thereof. For example, the microalgae growth promoter of the present invention contains at least one oxo fatty acid selected from 13-oxo-9,11-octadecadienoic acid and/or 9-oxo-10,12-octadecadienoic acid or A derivative or a salt thereof and at least one hydroxylated fatty acid selected from 9,10,13-trihydroxy-11-octadecaenoic acid and/or 9,12,13-trihydroxy-10-octadecaenoic acid or a derivative thereof or a salt thereof and at least one compound selected from

The unsaturated fatty acid of the present invention is not particularly limited, but an unsaturated fatty acid having about 10 to 20 carbon atoms has the effect of promoting the absorption of the oxo fatty acid and the hydroxylated fatty acid by the microalgae. This is because the cell membrane of microalgae is composed of lipids, and the oxo fatty acid and the hydroxylated fatty acid are more likely to permeate the cell membrane when the unsaturated fatty acid having about 10 to 20 carbon atoms is contained. For example, C18 unsaturated fatty acids are preferred. In the unsaturated fatty acid of the present invention, the number of unsaturated bonds in its molecular structure is not limited, and it may be a monounsaturated fatty acid or a polyunsaturated fatty acid. For example, unsaturated fatty acids include, but are not limited to, unsaturated fatty acids such as oleic acid, linoleic acid, oleic acid, α-linolenic acid, γ-linolenic acid, arachidonic acid, and the like. In addition, the unsaturated fatty acid may be either a free fatty acid or a salt thereof (a generally usable salt such as those exemplified above), and one or more of these may be used. can be selected. As the unsaturated fatty acid of the present invention, a commercially available product may be used, or a synthesized product from a commercially available compound may be used. As the unsaturated fatty acid, one type of unsaturated fatty acid may be used, or two or more types may be used.

When the compounds exemplified in this specification have isomers, all possible isomers can be used in the present invention unless otherwise specified.

As a specific example of the microalgae growth promoter of the present invention, at least one compound selected from at least one oxo fatty acid or its derivative or its salt and at least one hydroxylated fatty acid or its derivative or its salt, and A case of containing at least one unsaturated fatty acid (excluding oxo fatty acids and hydroxylated fatty acids) will be described.

That is, said unsaturated fatty acids that may be used in the present invention are not limited to compatibility with any particular type of oxo fatty acid or derivative thereof or salt thereof or hydroxylated fatty acid or derivative thereof or salt thereof, A wide variety of unsaturated fatty acids can be used with the oxo fatty acids or derivatives or salts thereof and hydroxylated fatty acids or derivatives or salts thereof in the microalgal growth promoters of the present invention. For example, the microalgae growth promoter of the present invention includes at least one oxo fatty acid selected from 13-oxoODA and 9-oxoODA or a derivative thereof or a salt thereof and 9,10,13-trihydroxy-11-octadecaenoic acid and/or or at least one hydroxylated fatty acid selected from 9,12,13-trihydroxy-10-octadecaenoic acid or a derivative thereof or a salt thereof, and at least one compound selected from oleic acid, linoleic acid and α-linolene It may contain at least one unsaturated fatty acid selected from acid, γ-linolenic acid, and arachidonic acid. For example, the microalgae growth promoter of the present invention includes at least one compound selected from ketooctadecadienoic acid or a derivative thereof or a salt thereof and hydroxyoctadecaenoic acid or a derivative thereof or a salt thereof, and oleic acid. , linoleic acid, α-linolenic acid, γ-linolenic acid and arachidonic acid. For example, the microalgae growth promoter of the present invention may comprise 13-oxo-9,11-octadecadienoic acid or a derivative thereof or a salt thereof and linoleic acid, 9,10,13-trihydroxy -11-octadecaenoic acid and/or 9,12,13-trihydroxy-10-octadecaenoic acid or derivatives or salts thereof and linoleic acid, 13-oxo-9,11-octadecadienoic acid and/or 9,10,13-trihydroxy-11-octadecaenoic acid and/or 9,12,13-trihydroxy-10-octadecaenoic acid or derivatives or salts thereof and linoleic acid.

In the present invention, at least one compound selected from at least one oxo fatty acid or its derivative or its salt and at least one hydroxylated fatty acid or its derivative or its salt, and at least one unsaturated fatty acid are mixed. In order to uniformly mix them, at least one compound selected from the at least one oxo fatty acid or derivative thereof or salt thereof, at least one hydroxylated fatty acid or derivative thereof or salt thereof, and at least one It is desirable to use a stabilizer (emulsifier) for stably presenting two unsaturated fatty acids in water as an emulsion.

At least one selected from potassium carbonate and dipotassium hydrogen phosphate can be used as the stabilizer (emulsifier).

In the microalgae growth promoter of the present invention, when unsaturated fatty acids (excluding oxo fatty acids and hydroxylated fatty acids) are included, oxo fatty acids or derivatives thereof or salts thereof and hydroxylated fatty acids or derivatives thereof for the unsaturated fatty acids Alternatively, the ratio of at least one compound selected from salts thereof is preferably about 90% or less by weight. When the ratio of at least one compound selected from oxo fatty acid or its derivative or its salt and hydroxylated fatty acid or its derivative or its salt to the unsaturated fatty acid is greater than 90%, the microalgae growth promoter This is because the content of unsaturated fatty acids is small, and it is considered that the effect of promoting the absorption of oxo fatty acids and hydroxylated fatty acids to microalgae cannot be sufficiently expected.

Further, the ratio of at least one compound selected from oxo fatty acid or its derivative or its salt and hydroxylated fatty acid or its derivative or its salt to the unsaturated fatty acid in the microalgae growth promoter is, by weight, It is preferable to contain about 10% or more. When the ratio of at least one compound selected from oxo fatty acid or its derivative or its salt and hydroxylated fatty acid or its derivative or its salt to the unsaturated fatty acid is less than 10%, the microalgae growth promoter The amount of the active ingredient for the effect of promoting growth is small, and there is a possibility that the effect of promoting the growth of microalgae will be insufficient.

The microalgae growth promoter of the present invention may be in any dosage form such as liquid, powder, granules, or tablets. For example, in view of ease of administration to microalgae, the drug may be in liquid form (i.e., liquid formulation), and in view of ease of transportation and storage, the drug may be in solid form (i.e., powder formulation). , granules, or tablets). The microalgae growth promoter of the present invention may also be in the form of a dry product made into a powder form using a conventional drying method. Preferably, drying may be performed by, for example, a freeze-drying method. Preferably, the microalgae growth promoter of the present invention may be a lyophilized powder. Further, the microalgae growth promoter of the present invention may be a pulverized or crushed freeze-dried product.

The microalgae growth promoter of the present invention may optionally contain additives or carriers suitable for application to microalgae, such as excipients, binders and disintegrants.

The microalgae growth promoter of the present invention can be used as a medium for microalgae. Accordingly, the present invention also relates to a method for culturing microalgae, which comprises culturing microalgae using the microalgae growth promoter of the present invention. When the microalgae growth promoter of the present invention is used as a medium, at least one selected from at least one oxo fatty acid or its derivative or its salt and at least one hydroxylated fatty acid or its derivative or its salt By adding an appropriate amount of various additives to a medium containing a compound and at least one unsaturated fatty acid (excluding oxo fatty acids and hydroxylated fatty acids) added as necessary, the medium contains microalgae It may be prepared so as to have a composition suitable for culture according to the type. Examples of such additives include, but are not limited to, sugars, organic acids, inorganic acids, organic bases, inorganic bases, vitamins, amino acids, peptides, proteins, and various ions (including natural seawater and artificial seawater). are mentioned.

The medium can be used as a medium in a normal culture process depending on the type of microalgae. As in normal culture, even in culture using the microalgae growth promoting agent of the present invention as a medium, culture conditions such as light intensity (light irradiation intensity), temperature, CO ₂ and nutrient supply are different. It may vary depending on the type of algae. For example, although the optimum irradiation intensity of light may vary depending on the type of microalgae, it is sufficient to irradiate light with an intensity suitable for the microalgae to be cultured. In some cases, a certain condition of carbon dioxide is preferable, but since microalgae can grow using sugars and organic acids depending on the type of microalgae, conditions without carbon dioxide may be used. Culturing temperature may also be performed under conditions suitable for the microalgae to be cultured. In addition, if necessary, the culture solution containing the microalgae being cultured may be stirred or circulated at an appropriate intensity. Cultivation time is not particularly limited, but may be, for example, 1 to 30 days.

In addition, the medium can be appropriately pH adjusted by adding a suitable acid or base, if necessary. A suitable pH of the medium depends on the type of microalgae to be cultured, and may be adjusted to pH 6 to pH 7, for example.

Sugars that can be added to the medium include, but are not limited to, one or more sugars selected from glucose, galactose, fructose, maltose, sucrose, lactose, oligosaccharides, and sugar alcohols such as glycerol. mentioned.

The culture medium may be provided in a culture tank of a culture apparatus. The culture tank is selected from a stirring device, a vibrating device, a temperature control device, a pH control device, a turbidity measurement device, a light control device, a specific gas concentration measurement device such as O ₂ and CO ₂ , and a pressure measurement device 1 or Multiple devices may be provided. Microalgae can be cultured by any suitable liquid culture method such as batch culture method, semi-batch culture method (fed-batch culture method), continuous culture method (perfusion culture method), and the like.

Microalgae that can be used with the microalgae growth promoter of the present invention are not particularly limited, but since valuable substances can be extracted from cultured microalgae, sugars, proteins, oils, compounds, etc. and / or microalgae that themselves have food applications and cosmetic applications are preferred, and it is considered beneficial to apply to microalgae that accumulate oils and fats as storage substances. . Microalgae can be grown efficiently, and the yield of valuables can be increased. Examples of such microalgae include euglenoid algae, green algae belonging to Trebouxia algae, and algae belonging to the phylum Cyanobacteria. The microalgae growth promoter of the present invention is well applied to these microalgae, It can be propagated efficiently. For example, the microalgae growth promoter of the present invention is for at least one selected from Euglenoid algae (such as Euglena), Chlorella algae (such as Chlorella), or Eulermo cyanobacteria (such as Spirulina). can be used for, but not limited to, The microalgae to be cultured using the microalgae growth promoter of the present invention is not limited to one specific type of microalgae, and phytoplankton, which is a group of many types of microalgae, may be targeted. good. In addition, genetically modified cyanobacteria and microalgae can also be used as microalgae.

Valuables can be obtained by extracting and purifying from cultured microalgae. Such substances include raw materials and final products of pharmaceuticals, cosmetics, health foods, oils such as hydrocarbon compounds and triglycerides, alcohol compounds, energy alternatives, enzymes, proteins, nucleic acids, sugars, lipid compounds, carotenoids, etc. can be mentioned, and it is believed that the yield of these valuable substances from cultured microalgae can be increased by using the microalgae growth promoter of the present invention. Therefore, the present invention also relates to a method for producing a valuable substance, characterized by using a product produced by microalgae cultured using the microalgae growth promoter of the present invention. As a method for extracting valuables from microalgae, purification, extraction, fractionation, and the like generally used in this technical field can be appropriately used.

In one embodiment of the present invention, the microalgae growth promoter of the present invention contains at least one or more selected from potassium ions, carbonate ions, phosphate ions, calcium ions, and sodium ions. This is because these ions contribute to promoting the growth of microalgae.

When the microalgae growth promoter of the present invention contains these ions, the concentration of each ion is 10 mg/L or more for potassium ions, 5 mg/L or more for carbonate ions, and 5 mg/L for phosphate ions. L or more, 5 mg/L or more for calcium ions, and mg/L or more for sodium ions.

These ions may be derived from the stabilizer (emulsifier) described above, or may be derived from salts of oxo fatty acids or hydroxylated fatty acids. Furthermore, these ions may be added as additional additives to the microalgae growth promoter of the present invention.

The present invention will be described based on examples, but the present invention is not limited only to the examples.

[Example 1]
13-oxo-9,11-octadecadienoic acid (13-oxoODA) ((9Z,11E)-13-oxo-9,11-octadecadienoic acid), which is ketooctadecadienoic acid, as an oxo fatty acid or a derivative thereof or a salt thereof; Decadienoic acid, manufactured by Cayman Chemical Co.) was used. In addition, as a hydroxylated fatty acid or a derivative thereof or a salt thereof, 9,10,13-trihydroxy-11-octadecaenoic acid (9(S), 10(S) manufactured by Lalordan Fine Chemicals Co., Ltd.), which is hydroxyoctadecaenoic acid, , 13(S)-trihydroxy-11(E)-octadecaesenoic acid (9(S),10(S),13(S)-trihydroxy-11(E)-octadecenoic acid), and 9 , 12,13-trihydroxy-10-octadecaenoic acid (manufactured by Lalordan Fine Chemicals, 9(S), 12(S), 13(S)-trihydroxy-10(E)-octadecaenoic acid (in English, 9( A 2:1 mixture of S), 12(S), 13(S)-trihydroxy-10(E)-octadecenoic acid) was used. As the unsaturated fatty acid, linoleic acid (primary linoleic acid manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.) was used. 1 g of linoleic acid, 0.1 g of 13-oxoODA, 0.02 g of 9,10,13-trihydroxy-11-octadecaenoic acid, 0.01 g of 9,12,13-trihydroxy-10-octadecaenoic acid, and 0.5 g of dipotassium hydrogen phosphate were added and mixed. This mixture was dispersed in water to prepare a 2 L aqueous solution (aqueous dispersion) as a growth promoter liquid.

5 mL of Euglena culture solution (manufactured by Fujimedaka) was diluted with water to 250 mL, and 50 mL of the solution was dispensed into a transparent 100 mL glass bottle, and 1.0 mL of the above growth promoter solution was added to obtain the main culture solution. A comparative culture solution was prepared by adding 1.0 mL of water instead of the growth promoter solution. The main culture solution and the comparative culture solution were placed under a constantly lit fluorescent lamp in a room adjusted to room temperature of 25°C, and mixed by inversion once a day. The absorbance of each culture solution was measured at a wavelength of 660 nm with a cell length of 1 cm) to evaluate the growth rate of microalgae.

The turbidity of the main culture solution on the fourth day of culture was 0.0421, and the turbidity of the comparative culture solution was 0.0296. Cell proliferation was promoted about 1.4 times by the microalgae growth promoter of the present invention.

[Comparative Example 1]
Solution A obtained by dispersing 1 g of linoleic acid in 2 L of water, solution B obtained by dispersing 1 g of oleic acid (primary oleic acid manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) in 2 L of water, and 0.5 g of dipotassium hydrogen phosphate. A solution C dispersed in 2 L of water was prepared. 1.0 mL of this was added to each of three 50 mL/100 mL glass bottles of Euglena culture diluent prepared in the same manner as in Example 1, and cultured under the conditions of Example 1, and then turbidity was measured.

The turbidity of the solution A-added culture medium on day 4 of culture was 0.0257 (compared to the comparative culture medium 0.9), the turbidity of the solution B-added culture medium was 0.0301 (compared to the comparative culture medium 1.0), and the solution The turbidity of the C-added culture solution was 0.0291 (1.0 compared to the comparative culture solution). The turbidity of each culture medium was equivalent to that of the comparative culture medium of Example 1, and linoleic acid, oleic acid, and dipotassium hydrogen phosphate alone showed no growth promoting effect.

[Example 2]
A growth promoter liquid was prepared in the same manner as in Example 1. A solution obtained by diluting 0.5 mL of chlorella culture solution (manufactured by Medaka Gakuen) to 500 mL with water was dispensed into 50 mL of a transparent 100-mL glass bottle, and 0.5 mL of the growth promoter solution was added to obtain the main culture solution. A comparative culture solution was prepared by adding 0.5 mL of water instead of the growth promoter solution. The main culture solution and the comparative culture solution were placed under a constantly lit fluorescent lamp in a room adjusted to room temperature of 25°C, mixed by inversion once a day, and the turbidity of each culture solution was measured with a spectrophotometer. and evaluated the growth rate of microalgae.

The turbidity of the main culture solution on day 4 of culture was 0.4559, and the turbidity of the comparative culture solution was 0.4061. Cell proliferation was promoted about 1.1 times by the microalgae growth promoter of the present invention.

[Comparative Example 2]
Solutions A, B and C were prepared in the same manner as in Comparative Example 1. 0.5 mL of this solution was added to each of three 50 mL/100 mL glass bottles of chlorella culture diluent prepared in the same manner as in Example 2, cultured under the conditions of Example 2, and then turbidity was measured.

The turbidity of the solution A-added culture medium on day 4 of culture was 0.4082 (compared to the comparative culture medium 1.0), the turbidity of the solution B-added culture medium was 0.4141 (compared to the comparative culture medium 1.0), and the solution The turbidity of the C-added culture solution was 0.4099 (1.0 compared to the comparative culture solution). The turbidity of each culture medium was equivalent to that of the comparative culture medium of Example 2, and linoleic acid, oleic acid, and dipotassium hydrogen phosphate alone did not show any growth-promoting effect.

[Example 3]
A growth promoter liquid was prepared in the same manner as in Example 1. 50 mL of a solution obtained by diluting 10 mL of Spirulina culture solution (manufactured by Fujimedaka) to 250 mL with water was dispensed into a transparent 100 mL glass bottle, and 0.05 mL of the above growth promoter solution was added to prepare the main culture solution. A comparative culture solution was prepared by adding 0.05 mL of water instead of the growth promoter solution. The main culture solution and the comparative culture solution were placed under a constantly lit fluorescent lamp in a room adjusted to room temperature of 25°C, mixed by inversion once a day, and the turbidity of each culture solution was measured with a spectrophotometer. and evaluated the growth rate of microalgae.

The turbidity of the main culture solution on day 4 of culture was 0.5234, and the turbidity of the comparative culture solution was 0.4434. Cell growth was promoted about 1.2 times by the microalgae growth promoter of the present invention.

[Comparative Example 3]
Solutions A, B and C were prepared in the same manner as in Comparative Example 1. 0.05 mL of this was added to each of three 50 mL/100 mL glass bottles of spirulina culture diluent prepared in the same manner as in Example 3, cultured under the conditions of Example 2, and then turbidity was measured.

The turbidity of the solution A-added culture medium on day 4 of culture was 0.4265 (compared to the comparative culture medium 1.0), the turbidity of the solution B-added culture medium was 0.4345 (compared to the comparative culture medium 1.0), and the solution The turbidity of the C-added culture solution was 0.4539 (1.0 compared to the comparative culture solution). The turbidity of each culture medium was equivalent to that of the comparative culture medium of Example 3, and linoleic acid, oleic acid, and dipotassium hydrogen phosphate alone showed no growth promoting effect.

From the above results, it can be seen that the growth promoter for microalgae of the present invention is a growth promoter with a high growth-promoting effect capable of efficiently growing microalgae.

Claims (22)

A microalgae growth promoter comprising at least one compound selected from (1) oxo fatty acid or its derivative or its salt, or (2) hydroxylated fatty acid or its derivative or its salt. The microalgae growth promoter according to claim 1, further comprising an unsaturated fatty acid (excluding the oxo fatty acid and the hydroxylated fatty acid). The microalgae growth promoter according to claim 2, wherein the unsaturated fatty acid is an unsaturated fatty acid having 10 to 20 carbon atoms. 4. The unsaturated fatty acid according to claim 2 or 3, wherein the unsaturated fatty acid is selected from the monovalent or polyunsaturated fatty acid group consisting of oleic acid, linoleic acid, α-linolenic acid, γ-linolenic acid and arachidonic acid. A growth promoter for microalgae as described. The microalgae growth promoter according to any one of claims 2 to 4, wherein the unsaturated fatty acid is linoleic acid. The microalgae growth promoter according to any one of claims 1 to 5, wherein the oxo fatty acid or derivative or salt thereof has the following formula:
HOOC-(R ¹ )-CH=CH-C(=O)-R ² (I)
(In the formula,
R ¹ : a linear or branched, saturated or unsaturated hydrocarbon group containing 6 to 12 carbon atoms;
R ² : an alkyl group having 2 to 8 carbon atoms, which may contain one or more branches and/or double bonds)
is an oxo fatty acid having a structural formula of or a derivative thereof or a salt thereof. 7. The oxo fatty acid according to any one of claims 1 to 6, wherein the hydrocarbon group of R ¹ of said oxo fatty acid has 8 to 10 carbon atoms and the alkyl group of R ² of said oxo fatty acid has 4 to 6 carbon atoms. or 1. Microalgae growth promoter according to 1. The microalgae growth promoter according to any one of claims ¹ to 7, wherein the oxo fatty acid is a It is an oxo fatty acid containing a double bond that forms a double bond and a conjugated double bond. The microalgae growth promoter according to any one of claims 1 to 8, wherein the oxo fatty acid is a linear or branched hydrocarbon group having 9 carbon atoms in R ¹ of the oxo fatty acid. , R ² is an oxo-fatty acid in which R 2 is an alkyl group having 5 carbon atoms. The microalgae growth promoter according to any one of claims 1 to 9, wherein said oxo fatty acid is ketooctadecadienoic acid. The microalgae growth promoter according to any one of claims 1 to 10, wherein said oxo fatty acid is 13-oxo-9,11-octadecadienoic acid. The microalgae growth promoter according to any one of claims 1 to 11, wherein the hydroxylated fatty acid or derivative thereof or salt thereof is represented by the following formulas (II) and/or (III):
HOOC-(R ³ )-CH(OH)-CH(OH)-CH=CH-CH(OH)-R ⁴ (II)
HOOC-(R ³ )-CH(OH)-CH=CH-CH(OH)-CH(OH)-R ⁴ (III)
(In the formula,
R ³ is a straight-chain or branched hydrocarbon group having 4 to 12 carbon atoms, which may contain one or more double bonds and/or OH groups, The position of the double bond is not limited if it contains
R ⁴ is a straight-chain or branched hydrocarbon group having 2 to 8 carbon atoms and optionally containing one or more double bonds and/or OH groups, The position of the double bond is not limited if it contains
is a hydroxylated fatty acid having the structural formula of or a derivative thereof or a salt thereof. 13. The microalgae growth promoter of claim 12, wherein the hydroxylated fatty acid is
the hydrocarbon group of R ³ has 6 to 8 carbon atoms;
The hydrocarbon group of R ⁴ has 4 to 6 carbon atoms. The microalgae growth promoter according to claim 12 or 13, wherein the hydroxylated fatty acid is
R ³ has the structure —(CH ₂ ) _n — (n is an integer of 4 to 12);
R ⁴ is the structure C _n H _2n+1 - (where n is an integer from 2 to 8). The microalgae growth promoter according to any one of claims 12 to 14, wherein the hydroxylated fatty acid is
R ³ is an alkylene group having 7 carbon atoms (-(CH ₂ ) ₇ -),
R ⁴ is an alkyl group having 5 carbon atoms (CH ₃ CH ₂ CH ₂ CH ₂ CH ₂ --). The microalgae growth promoter according to any one of claims 1 to 15, wherein said hydroxylated fatty acid is hydroxyoctadecaenoic acid. The microalgae growth promoter according to any one of claims 1 to 16, wherein said hydroxylated fatty acid is 9,10,13-trihydroxy-11-octadecaenoic acid. The microalgae growth promoter according to any one of claims 1 to 17, wherein said hydroxylated fatty acid is 9,12,13-trihydroxy-10-octadecaenoic acid. The ratio of the at least one compound selected from the oxo fatty acid or its derivative or its salt and the hydroxylated fatty acid or its derivative or its salt to the unsaturated fatty acid is 10% to 90% by weight. The microalgae growth promoter according to any one of claims 1 to 18, comprising the unsaturated fatty acid so as to be. The microalgae growth promoter according to any one of claims 1 to 19, which is used as a medium for microalgae. The microalgae growth promoter according to any one of claims 1 to 20, wherein the microalgae growth promoter is used for at least one species selected from Euglena, Chlorella, and Spirulina. The microalgae growth promoter according to any one of claims 1 to 21, further comprising at least one selected from potassium ions, carbonate ions, phosphate ions, calcium ions, or sodium ions.