JP4924840B2 - Mannosyl erythritol lipid and method for producing the same - Google Patents

Description

  The present invention relates to a novel mannosyl erythritol lipid (hereinafter sometimes simply referred to as MEL) and a method for producing the same, and more specifically, MEL which is a kind of microorganism-produced glycolipid, wherein the mannosyl erythritol skeleton in the molecular structure is The present invention relates to MEL which is 1-O-β-D-mannopyranosyl-meso-erythritol and a method for producing microorganisms thereof.

  Glycolipids are substances in which 1 to 10 monosaccharides are bound to lipids, are involved in the transmission of information between cells in vivo, and play an important role in maintaining the functions of the nervous system and immune system. Etc. are being revealed. On the other hand, glycolipids are amphipathic substances that have both hydrophilic properties derived from the properties of sugars and lipophilic properties derived from the properties of lipids. being called.

  Until the petrochemical industry flourished, surfactants derived from biological components such as lecithin and saponin (biosurfactants) have been used, but synthetic surfactants have been developed by the development of the petrochemical industry. The production volume of cereals has increased dramatically, making it an indispensable substance in daily life. However, environmental pollution has spread as the amount of synthetic surfactant used has increased. Therefore, biosurfactants, which are highly biodegradable surface active substances, are being reviewed again in order to reduce the burden on the environment with high safety and development of various types of biosurfactants is desired. .

  A typical example of a biosurfactant is a surfactant produced by a microorganism. Currently, the surfactants produced by the above-described microorganisms are classified into five groups: glycolipids, acyl peptides, phospholipids, fatty acids, and polymer compounds. Of these, glycolipid-based surfactants have been best studied, and many types of substances produced by bacteria and yeast have been reported.

  Biosurfactants such as glycolipids are said to have high biodegradability, low toxicity, environmental friendliness, and novel physiological functions. Because of these properties, the wide application of biosurfactants to the food industry, cosmetic industry, pharmaceutical industry, chemical industry, environmental field, etc. has both the realization of a sustainable society and the provision of high-performance products. Meaningful.

  One typical glycolipid biosurfactant is mannosylerythritol lipid (MEL). MEL is a substance discovered from Ustilago nuda and Shizonella melanogramma (see Non-Patent Documents 1 and 2). Subsequently, Candida genus yeast (see Patent Document 1 and Non-patent Document 3) and Candida antarctica (currently Pseudozyma antarctica) (refer to Non-Patent Documents 4 and 5) that are mutant strains of itaconic acid production It is also reported that it can be produced by yeasts of the genus Kurtzmanomyces (see Non-Patent Document 6). At present, production of 300 g / L or more is possible by continuous culture and production for a long time.

The sugar skeleton possessed by the MEL has a plurality of asymmetric carbon atoms, and when the number is n, 2 ⁿ optical isomers exist. However, all the MELs reported so far have a 4-O-β-D-mannopyranosyl-meso-erythritol structure whose sugar skeleton is represented by the following formula (2).

  As the β-D-mannopyranosyl-meso-erythritol structure, another isomer of 1-O-β-D-mannopyranosyl-meso-erythritol structure (the following formula (3)) is assumed.

  By synthesizing one kind of MEL having this 1-O-β-D-mannopyranosyl-meso-erythritol structure, it was proved that the sugar skeleton of the conventional MEL has the structure of the above formula (2). (Non-patent Document 7).

  For organic compounds having physiological activity, the chirality of the molecule is a very important point. So far, MEL has been reported to have various physiological activities including antibacterial properties, antitumor properties, and glycoprotein binding ability (Non-patent Document 8). In addition, MEL exhibits extremely unique self-assembly properties, and attempts have been made to develop liposome materials and liquid crystal technology using them, and the slight difference in molecular structure has a significant effect on the formation of self-assemblies. Have also been reported (Non-Patent Documents 8 and 9).

Therefore, it is expected that the production of MEL optical isomers which have been conventionally known in large quantities, and their physical property comparison and functional evaluation will greatly contribute to the development of MEL applications.
Japanese Patent Publication No.57-145896 R. H. RH Haskins, Jay. A. Tone (JA Thorn), B. Boothroyd, “Can. J. Microbiol.”, Volume 1, p 749-756 (1955). Gee. G. Deml, Tee. T. Anke, F. F. Oberwinkler, B. M. BM Giannetti, W. Steglich, “Phytochemistry”, Vol. 19, p83-87 (1980). Tee. Nakahara, H. Kawasaki, T. T. Sugisawa, Wy. Y. Takamori, Tee. T. Tabuchi, “Journal of Fermentation Technology” (Japan), Japan Fermentation Engineering Society, 61, p19-23 (1983). Di. Kitamoto, S. Akiba, See. C. Hioki, Tee. T. Tabuchi, “Agric. Biol. Chem.”, (Japan), Japan Society for Agricultural Chemistry, Volume 54. p31-36 (1990). H. S. Kim (H.-S. Kim), Bee. Di. Yoon (B.-D. Yoon), Di. H. D.-H. Choung, H. M. Oh (H.-M. Oh), Tee. T. Katsuragi, Wye. Y. Tani "Appl. Microbiol. Biotechnol.", (Germany), Springer-Verlag, 52, p713-721 (1999). K. kakukawa, M. Tamai, K. Imamura, K. Miyamoto, S. Miyoshi, Y. Morinaga, O. Suzuki, Miyagawa (T. Miyakawa) “Bioscience, Biotechnol. Biochem.” (Japan), Japan Society for Agricultural Chemistry, 66, p188-191 (2002). Di. D. Crich, M. A. MA Mora, Earl. R. Cruz “Tetrahedron” (Netherlands), Elsevier, 58, p35-44 (2002). Dai Kitamoto “Oreoscience” (Japan), Japan Oil Chemists' Society, Volume 3, p663-672 (2003). Tee. T. Imura, N. N. Ohta, K. Inoue, N. N. Yagi, H. H. Negishi, H. H. Yanagishita, Di. Kitamoto “Chemistry European Journal (Chem. Eur. J)” (USA), Wiley, Vol. 12, p 2434-2440 (2006).

  As described above, it is widely used in the food industry, cosmetics industry, pharmaceutical industry, chemical industry, environmental fields, etc., so biodegradable, such as glycolipids with high degradability, low toxicity, environmental friendliness, and novel physiological functions. For surfactants, it is important to improve production efficiency and expand the variety of structures and functions. In particular, MEL is not only excellent in productivity and interface physical properties, but also has been developed for various uses utilizing unique self-assembly properties and physiological activity.

  However, the MELs derived from microorganisms reported so far all have sugar structures with a 4-O-β-D-mannopyranosyl-meso-erythritol structure. For this reason, there has been a strong demand for an expanded variety of structures and functions.

  In addition, Non-Patent Document 7 describes that MEL having a 1-O-β-D-mannopyranosyl-meso-erythritol structure was obtained by chemical synthesis, but this is a very complicated process. It was synthesized after that and lacked versatility and was difficult to use.

  The present invention has been made in view of the above-described problems, and its object is an optical isomer of MEL having a conventional 4-O-β-D-mannopyranosyl-meso-erythritol structure. An object of the present invention is to provide a MEL having a 1-O-β-D-mannopyranosyl-meso-erythritol structure and a method for producing the same.

  As a result of diligent efforts to achieve the above object, the inventors of the present invention have developed a conventional MEL having a 4-O-β-D-mannopyranosyl-meso-erythritol structure (hereinafter referred to as “conventional MEL” or “4-O—”). MEL having a 1-O-β-D-mannopyranosyl-meso-erythritol structure (hereinafter referred to as “MEL according to the present invention” or “1- In some cases, the microorganisms producing "O-MEL" are found, and the present invention has been completed. That is, the present invention includes the following inventions.

  (1) A mannosyl erythritol lipid having a structure represented by the following general formula (1).

(In the formula (1), the substituent R ¹ may be the same or different and is an aliphatic acyl group having 4 to 24 carbon atoms, and the substituent R ² may be the same or different and represents hydrogen or an acetyl group. The substituent R ³ represents hydrogen or an aliphatic acyl group having 2 to 24 carbon atoms, provided that both the substituent R ¹ are aliphatic acyl groups having 12 carbon atoms and both the substituent R ² are acetyl. Groups, wherein the substituent R ³ is hydrogen.)
(2) The mannosyl erythritol lipid according to (1), wherein in the general formula (1), any one of the substituents R ² is an acetyl group and the other is hydrogen.

(3) The mannosyl erythritol lipid according to (1) or (2), wherein in the general formula (1), the substituent R ³ is an aliphatic acyl group having 2 to 24 carbon atoms.

  (4) The mannosyl erythritol lipid according to any one of (1) to (3), which is produced by a microorganism.

  (5) Mannosyl erythritol lipid production that produces a mannosyl erythritol lipid having a structure represented by the following general formula (1) by culturing a microorganism belonging to the genus Pseudozyma and capable of producing a mannosyl erythritol lipid. Method.

(In the formula (1), the substituent R ¹ may be the same or different and is an aliphatic acyl group having 4 to 24 carbon atoms, and the substituent R ² may be the same or different and represents hydrogen or an acetyl group. The substituent R ³ represents hydrogen or an aliphatic acyl group having 2 to 24 carbon atoms.
(6) The method for producing mannosyl erythritol lipid according to (5), wherein the microorganism is Pseudozyma tsukubaensis or Pseudozyma crassa.

  The MEL according to the present invention is a conventionally known optical isomer of MEL. Differences in molecular chirality greatly affect physiological activity and ability to form self-assemblies, so that there is no difference in surface activity from conventional MEL, but it exhibits different behavior in other properties. Become. Therefore, by performing physical property comparison and function evaluation with the conventional MEL using the MEL according to the present invention, it is possible to greatly contribute to the development of MEL applications. In particular, the MEL according to the present invention has an effect of having a liquid crystal forming ability different from that of the conventional MEL.

  In addition, according to the method for producing MEL according to the present invention, conventionally known optical isomers of MEL can be easily produced in large quantities.

  An embodiment of the present invention will be described as follows.

<1. Mannosyl erythritol lipid (MEL)>
In order to help understanding of the MEL according to the present invention, the conventional MEL is first outlined.

  Conventional MEL is obtained by culturing MEL-producing bacteria. A typical example of the chemical structure thereof is 4-O-β-D-mannopyranosyl-meso-erythritol, as shown in the following general formula (4). It is what.

  In the general formula (4), the substituent R is a hydrocarbon group (an alkyl group or an alkenyl group). As the conventional MEL, four types of MEL-A, MEL-B, MEL-C and MEL-D are known from the presence or absence of acetyl groups at the 4-position and 6-position of mannose.

First, in MEL-A, in the general formula (4), the substituents R ¹ and R ² are both acetyl groups. In MEL-B, in the general formula (4), the substituent R ¹ is an acetyl group and the substituent R ² is hydrogen. In MEL-C, in the general formula (4), the substituent R ¹ is hydrogen and the substituent R ² is an acetyl group. In MEL-D, in the general formula (4), the substituents R ¹ and R ² are both hydrogen.

  The carbon number of the substituent R in the above MEL-A to MEL-D varies depending on the carbon number of the fatty acid constituting the triglyceride in the fats and oils contained in the MEL production medium and the degree of utilization of the fatty acid of the MEL-producing bacterium used. To do. In addition, when the triglyceride has an unsaturated fatty acid residue, an unsaturated fatty acid residue can be included as the substituent R if the MEL-producing bacterium does not assimilate up to the double bond portion of the unsaturated fatty acid. . As is clear from the above description, each obtained MEL is usually in the form of a mixture of compounds in which the fatty acid residue portion of the substituent R is different.

On the other hand, the MEL according to the present invention has a structure represented by the above general formula (1), and is greatly characterized in that erythritol in the MEL is an optical isomer introduced in the opposite direction to the conventional MEL. . In the above general formula (1), the substituent R ¹ may be the same or different and may be an aliphatic acyl group having 4 to 24 carbon atoms, and the substituent R ² may be the same or different and is hydrogen or acetyl. Represents a group. The substituent R ³ represents hydrogen or an aliphatic acyl group having 2 to 24 carbon atoms. However, the substituent R ¹ is both an aliphatic acyl group having 12 carbon atoms, the substituent R ² is both an acetyl group, and the substituent R ³ is hydrogen. Note that this is intended to exclude the MEL disclosed in Non-Patent Document 7 described above, has no other intention, and is not a limitation that unduly limits the scope of rights of the present invention.

Further, the substituent R ¹ in the general formula (1) may be a saturated aliphatic acyl group or an unsaturated aliphatic acyl group, and is not limited. When it has an unsaturated bond, it may have a plurality of double bonds. The carbon chain may be linear or branched. In the case of an oxygen atom-containing hydrocarbon group, the number and position of oxygen atoms contained are not limited.

Further, in the general formula (1), it is preferable that any one of the substituents R ² is an acetyl group and the other is hydrogen. That is, it is 1-O-MEL and is preferably MEL-B or MEL-C. In particular, it is more preferable that the 4-position is hydrogen and the 6-position is an acetyl group, that is, MEL-B.

For example, compared with MEL-A (two acetyl groups), MEL-B or MEL-C (one acetyl group) has higher polarity and different self-organization behavior in water. Therefore, unlike the liquid crystal of the form to be formed, with respect to making the sponge phase in MEL-A in wide concentration region _{(L 3} phase), etc., MEL-B or MEL-C in lamellar phase (L _alpha) Easy to make. The lamellar phase is very close to the stratum corneum of the skin, so it has good skin penetration and is useful as a skin care material. Furthermore, since MEL-B can easily form vesicles (liposomes) encapsulated in bilayer membranes and encapsulate drugs in capsules, it is expected to be easily applied to liposome cosmetics and pharmaceuticals (the above non-patent document). (See 8, 9).

  The MEL synthesized in Non-Patent Document 7 is of the A type and both of the fatty acid chains are C12. In contrast, in the present invention, MEL-B and MEL-C can be produced, and the fatty acid chain length can also be varied. As a result, it is possible to provide a MEL having a different liquid crystal forming ability (see FIGS. 7 and 8 to be described later).

  The synthesis method described in Non-Patent Document 7 is limited only to the synthesis method of MEL-A. In order to synthesize MEL-B and C, the use of different protecting groups and reactions of different steps are performed. It should be repeated, and it should be noted that the MEL according to the present invention cannot be synthesized even if the above literature is taken into consideration.

In the general formula (1), the substituent R ³ is preferably an aliphatic acyl group having 2 to 24 carbon atoms. In the formula (1), if both of the substituents R ¹ and R ³ are aliphatic acyl groups, they become triacyl MEL, and MEL having properties different from those of diacyl MEL can be obtained.

  Specifically, the triacyl body has a lower HLB (hydrophilic-hydrophobic balance) than the conventional diacyl body and is a more lipophilic surfactant. For this reason, application uses differ. For example, utilization to a W / O emulsion, a dispersing agent, etc. can be considered. In addition, as described above, the synthesis method described in Non-Patent Document 7 is limited only to the synthesis method of diacyl MEL-A, and fundamentally different synthesis routes (different protecting groups and Multi-step reaction). Therefore, the MEL according to the present invention cannot be synthesized even in consideration of the non-patent document 7.

The molecular structure of the MEL according to the present invention is basically obtained in the form of a mixture of compounds different in the carbon number of the aliphatic acyl group of the substituent R ¹ in the general formula (1) or the presence or absence of a double bond. However, these can be converted into a single MEL compound by further purification by preparative HPLC or the like.

  Like the conventional MEL, the MEL of the present invention has a high surface activity, has new physiological activity and self-assembly properties, and can be used as various catalysts for surfactants or fine chemicals. Furthermore, MEL is a very significant substance in that it is biodegradable and has high safety. In other words, it is a biosurfactant with high biodegradability, low toxicity and environmental friendliness.

  Furthermore, it has been reported that conventional MEL has various physiological activity. For example, when MEL is allowed to act on human acute promyelocytic leukemia cell line HL60, it has the effect of inducing differentiation of leukemia cells that differentiates the granule system. In addition, when MEL is allowed to act on PC12 cells derived from rat adrenal medullary pheochromocytoma, it has physiological activity such as neural cell differentiation inducing action that causes neurite outgrowth, and for the first time as a microbially produced glycolipid, It has been reported that apoptosis can be induced (X. Zhao et. Al., Cancer Research, 59, 482-486 (1999)) and that it has a cancer cell growth inhibitory effect. In view of the physiological action of these conventional MELs, the MEL according to the present invention can be expected to have various physiological activities. For example, it can be used as a medicine such as an anticancer agent or a novel cosmetic material.

  In addition, the MEL according to the present invention is remarkably different from the conventional MEL in the liquid crystal forming ability due to the difference in molecular chirality, as shown in Examples described later. Specifically, the MEL according to the present invention has the ability to form a lamellar phase in a very wide concentration region as compared with the conventional MEL, and can be said to be a biosurfactant with extremely excellent liquid crystal forming ability.

  In addition, as a method for evaluating the liquid crystal forming ability described above, it can be confirmed by a conventionally known method. For example, a water intrusion method is given as a simple comparison method of the liquid crystal forming ability. The behavior of liquid crystal formation can be traced by applying MEL on a slide glass, dropping distilled water beside it and observing the liquid crystal phase formed at the interface under a microscope. By using the above method, the liquid crystal forming ability of the conventional MEL and the MEL optical isomer of the present invention can be easily compared.

<2. Manufacturing method of MEL>
The method for producing MEL according to the present invention is characterized by using a microorganism having an ability to produce 1-O-MEL. Specifically, for example, a MEL that produces a mannosyl erythritol lipid having a structure represented by the above general formula (1) by culturing a microorganism that belongs to the genus Pseudozyma and has the ability to produce mannosyl erythritol lipid. It is a manufacturing method. In the description explaining the production method of the present MEL, in the general formula (1), the substituent R ¹ may be the same or different and is an aliphatic acyl group having 4 to 24 carbon atoms. ² may be the same or different and each represents hydrogen or an acetyl group. The substituent R ³ represents hydrogen or an aliphatic acyl group having 2 to 24 carbon atoms.

<2-1. Microorganisms used>
Among the microorganisms that belong to the genus Pseudozyma and have the ability to produce MEL, microorganisms that can be used in the MEL production method according to the present invention are those that produce the MEL optical isomer represented by the above formula (1). There is no particular limitation as long as it is present.

  Examples of microorganisms that produce MEL of the above general formula (1) include, for example, microorganisms belonging to Pseudozyma tsukubaensis or Pseudozyma crussa, among which microorganisms belonging to Pseudozyma tsukubaensis are preferred. For example, microorganisms belonging to Pseudozyma tsukubaensis are highly effective in improving the productivity of MEL when cultured at 25-30 ° C., for example, in the case of Pseudozyma tsukubaensis JCM 10324, the best production is obtained at a culture temperature of 30 ° C. Sex is obtained.

<2-2. Medium used and culture method>
As the medium, for example, a medium generally used for general microorganisms or yeast can be used, and the medium is not particularly limited, and a medium used for yeast is particularly preferable. Examples of such a medium include YPD medium (yeast extract 10 g, polypeptone 20 g, and glucose 100 g). In particular, when using Pseudozyma tsukubaensis JCM 10324 strain, it has been found that the culture temperature is preferably set to 27 ° C to 33 ° C. This is because the productivity of MEL is significantly improved as described above.

Furthermore, a preferable medium composition when MEL is produced using a microorganism that can be used in the MEL production method of the present invention, in particular, Pseudozyma tsukubaensis JCM 10324 strain is as follows.
-Yeast extract; preferably 0.1-2 g / L, particularly preferably 1 g / L- Sodium nitrate; 0.1-1 g / L is preferred, and 0.3 g / L is particularly preferred.
-Potassium dihydrogen phosphate; 0.1-1 g / L is preferable and 0.3 g / L is particularly preferable.
Magnesium sulfate: 0.1 to 1 g / L is preferable, and 0.3 g / L is particularly preferable.
-Fats and oils; 40 g / L or more is preferable, and 80 g / L is particularly preferable.

  In the culture of the microorganism, it is preferable to add a carbon source to the medium. As the carbon source, fats and oils, fatty acids, fatty acid derivatives (fatty acid esters such as fatty acid triglycerides), or synthetic esters may be contained, and a mixture of plural kinds may be contained. There is no restriction and can be selected as appropriate based on the technical level at the time of use of the present invention.

  “Oils and fats” may be vegetable oils, animal oils, mineral oils and hardened oils thereof. Specifically, avocado oil, olive oil, sesame oil, camellia oil, evening primrose oil, turtle oil, macadamia nut oil, corn oil (corn oil), mink oil, rapeseed oil, egg yolk oil, persic oil, peanut oil, safflower oil , Wheat germ oil, sasanqua oil, castor oil, flaxseed oil, safflower oil, cottonseed oil, eno oil, soybean oil, peanut oil, teaseed oil, kaya oil, rice bran oil, kiri oil, jojoba oil, cacao butter, palm oil Such as horse oil, palm oil, palm kernel oil, beef tallow, sheep fat, lard, lanolin, whale wax, beeswax, carnauba wax, molasses, candelilla wax, squalane, etc. and its hardened oil, liquid paraffin, petrolatum, etc. Synthetic triglycerin such as mineral oil and glycerin tripalmitate. Preferably avocado oil, olive oil, sesame oil, camellia oil, evening primrose oil, turtle oil, macadamia nut oil, corn oil, mink oil, rapeseed oil, egg yolk oil, persic oil, wheat germ oil, southern oil, castor oil, flaxseed oil , Safflower oil, cottonseed oil, eno oil, soybean oil, peanut oil, tea seed oil, kaya oil, rice bran oil, and more preferably olive oil and soybean oil.

  The “fatty acid” or “fatty acid derivative” is preferably derived from higher fatty acids, such as caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, oleic acid, linoleic acid, linolenic acid, stearic acid, behenic acid. , 12-hydroxystearic acid, isostearic acid, undecic acid, toluic acid, eicosapentaenoic acid, docosahexaenoic acid and the like. Preferred are lauric acid, myristic acid, palmitic acid, oleic acid, linoleic acid, linolenic acid, stearic acid and undecylenic acid, and more preferred are oleic acid, linoleic acid and undecylenic acid.

  Examples of the “synthetic ester” include methyl caproate, methyl caprylate, methyl caprate, methyl laurate, methyl myristate, methyl palmitate, methyl oleate, methyl linoleate, methyl linolenate, methyl stearate, undecine. Methyl acid, ethyl caproate, ethyl caprylate, ethyl caprate, ethyl laurate, ethyl myristate, ethyl palmitate, ethyl oleate, ethyl linoleate, ethyl linolenate, ethyl stearate, ethyl undecinate, vinyl caproate , Vinyl caprylate, vinyl caprate, vinyl laurate, vinyl myristate, vinyl palmitate, vinyl oleate, vinyl linoleate, vinyl linolenate, vinyl stearate, vinyl undecinate, cetyl octanoate , Octyldodecyl myristate, isopropyl myristate, myristyl myristate, isopropyl palmitate, butyl stearate, hexyl laurate, Oren'i acid decyl dimethyl octanoate, cetyl lactate, myristyl lactate, and the like. Preferred are methyl laurate, methyl myristate, methyl palmitate, methyl oleate, methyl linoleate, methyl linolenate, methyl stearate, methyl undecylate, more preferably methyl oleate, methyl linoleate, and methyl undecylate. .

  You may use these individually by 1 type or in mixture of 2 or more types as appropriate.

The specific steps of the MEL production method according to the present invention are not particularly limited, and can be appropriately selected according to the purpose. For example, the scale is in the order of seed culture, main culture, and MEL production culture. It is preferable to keep up. Examples of culture media and culture conditions in these cultures are as follows.
a) Seed culture: 5 mL of liquid medium having a composition of glucose 40 g / L, yeast extract 1 g / L, sodium nitrate 0.3 g / L, potassium dihydrogen phosphate 0.3 g / L, and magnesium sulfate 0.3 g / L Inoculate one platinum loop into the test tube and shake culture at 30 ° C for 1 day.
b) Main culture; predetermined amount of fats and oils such as vegetable oil and fat, yeast extract 1 g / L, sodium nitrate 0.3 g / L, potassium dihydrogen phosphate 0.3 g / L, and magnesium sulfate 0.3 g / L A culture medium of a) is inoculated into a Sakaguchi flask containing 100 mL of the liquid medium having the composition of 2 and cultured at 30 ° C. for 2 days.
c) Mannosyl erythritol lipid production culture; predetermined amount of fats and oils such as vegetable oil and fat, yeast extract 1 g / L, sodium nitrate 0.3 g / L, potassium dihydrogen phosphate 0.3 g / L, and magnesium sulfate 0.3 g A jar fermenter containing 1.4 L of a liquid medium having a composition of / L is inoculated and cultured at 30 ° C. with a stirring speed of 800 rpm. In this culture, it is preferable that the vegetable fats and oils flow down into the culture vessel from the middle of the culture to maintain the fats and oils concentration in the medium at 20 to 200 g / L.

<2-3. MEL recovery method>
For the recovery of MEL, a conventionally known lipid purification method can be used and is not particularly limited. For example, after completion of the culture, a step of extracting the lipid component with this volume to 4 times volume of ethyl acetate and distilling off the ethyl acetate using an evaporator to recover the lipid and glycolipid component can be mentioned. Thereafter, this lipid component was dissolved in an equal amount of chloroform, and this was subjected to silica gel chromatography, and chloroform, chloroform: acetone (80:20), (70:30), (60:40), and (50: 50), the same (30:70), and acetone. Each solution is charged on a thin layer chromatography (TLC) plate and developed with chloroform: methanol: aqueous ammonia = 65: 15: 2 (volume ratio). After completion of the development, the presence of glycolipid is confirmed with an anthrone sulfate reagent. The eluate containing the glycolipid can be collected and the solvent can be distilled off to obtain a glycolipid component.

<2-4. Determination of MEL structure>
The structure determination of MEL obtained by the MEL production method described above can be performed by a conventionally known method, and is not particularly limited. For example, MEL obtained using Pseudozyma Tsukubaensis JCM 10324 strain An example of the structure determination method is as follows.

First, the isolated glycolipid component can be judged to be a glycolipid component by being colored blue-green with an anthrone sulfate reagent on a TLC plate. The fact that this glycolipid is MEL indicates that ¹ H, ¹³ C, two-dimensional NMR analysis was performed, and the obtained spectrum and conventional MEL (MEL-AD) having a known structure (the above general formula (4) ) And the spectrum can be easily confirmed.

  Whether the MEL according to the present invention is an optical isomer of a conventional MEL can be easily confirmed by performing 1) NMR analysis of sugar skeleton and 2) optical rotation measurement as follows.

1) NMR analysis of sugar skeleton In a ¹ H-NMR spectrum measured in deuterated chloroform, protons in the sugar chain portion of MEL are detected in the vicinity of 3.3 to 5.6 ppm. In particular, the mannose 1′-position (reducing terminal) proton involved in the glycosidic bond and the erythritol 4-position proton are detected at around 4.7 ppm and around 4.0 ppm, respectively. However, when the binding directions of erythritol are different, the proton-derived peaks are shifted. Reported by Crich et al. (See Non-Patent Document 7 above). Therefore, it is confirmed that the MEL according to the present invention shows a spectrum pattern in which only the above peak is shifted with respect to the conventional MEL.

Further, NMR analysis of a sugar chain (mannosylerythritol; sometimes abbreviated as ME) obtained by hydrolyzing the obtained MEL with an alkali (NaOCH ₃ ) is performed. By comparing the NMR spectra of the obtained MEL sugar chain and the conventional MEL sugar chain, the structure of the sugar chain part of the MEL according to the present invention is the conventional MEL (4-O-β-D-mannopyranosyl- It can be confirmed that the spectrum pattern is different from the meso-erythritol structure.

2) Optical rotation measurement By measuring the optical rotation of MEL or ME, the chirality of the conventional MEL and the MEL molecule according to the present invention can be compared (see Non-Patent Document 7 above). D. 1-O- (4 ′, 6′-di-O-dodecyl-2 ′, 3′-di-O-dodecyl-β-D-, which has the same sugar skeleton as the MEL of the present invention reported by Crich et al. Since the specific rotation of [mannopyranosyl) -D-erythritol is [α] _D = −25.9 ° (c = 1.5), the difference in the three-dimensional structure can be understood by comparing with reference to this.

  By the above method, it can confirm that MEL obtained by this invention differs in the three-dimensional structure of sugar skeleton from conventional MEL.

  As described above, according to the MEL manufacturing method of the present invention, the MEL is different from the conventional MEL, and it is possible to selectively produce an MEL that has not been reported to date for production by microorganisms. As described above, since the difference in molecular chirality has a great influence on the physiological activity and the ability to form self-assemblies, the MEL according to the present invention has no difference in surface activity from the conventional MEL. , It will behave differently in other properties. Therefore, the physical property comparison between the MEL according to the present invention and the conventional MEL shows an important factor for the functional evaluation of the MEL. As a result, accumulation of data relating to structure-property relationships such as physiological activity greatly contributes to the development of biosurfactant applications in various fields such as pharmaceuticals, foods, and cosmetics.

  Furthermore, it seems that the MEL according to the present invention can be synthesized theoretically even if a chemical synthesis method is used. However, when synthesizing by chemical synthesis, very special synthesis techniques and multi-step complex protection / deprotection reactions are required. Moreover, since it is extremely difficult to completely control the chirality in the first place, it can be said that it is extremely difficult to chemically synthesize in reality. On the other hand, the microorganism production method as shown in the present invention goes through an elaborate biosynthetic pathway, so that a special structure in which the position and the three-dimensional structure are completely controlled is maintained, and it is manufactured in only one step. Since a method can be provided, it can be a very effective means.

<Identification of 2-5.1-O-β-D-mannopyranosyl-meso-erythritol>
The 4-O-β-D-mannopyranosyl-meso-erythritol (hereinafter sometimes abbreviated as 4-O-ME) represented by the general formula (2) has heretofore been known as conventional MEL (4-O -MEL) is a known oligosaccharide alcohol synthesized by alkaline hydrolysis and reported as a result of structural analysis. A fermentation production method using glucose as a raw material using Candida yeast has also been reported (Japanese Patent Laid-Open No. 63-63390, T. Kobayashi et al., Argic. Biol. Chem. Vol. 51, pp.1715-1716). (1987)), it is expected to be effective as a component of cosmetics and pharmaceuticals.

  However, as described above, the sugar chain obtained by alkaline hydrolysis of the MEL according to the present invention is a 1-O-β-D-mannopyranosyl-meso-erythritol (hereinafter referred to as the following general formula (3)). 1-O-ME, which may be abbreviated). Although the structure is assumed by Crich et al. (See Non-Patent Document 7 above), there are no production examples and no reports on isolation / identification.

Regardless of whether they are monosaccharides or polysaccharides, there are a large number of asymmetric carbon atoms in the sugar chain, which are classified into a wide variety according to the difference in steric structure, and each has a specific function. In particular, since the difference in the three-dimensional structure of the sugar chain plays a central role in the unique biomolecular recognition mechanism, the difference in molecular chirality is considered to have a great influence on the physiological activity, and the method described in this specification. 1-O-ME obtained by 1 is expected to express physiological functions different from those of conventional 4-O-ME. In particular, sugar alcohols are widely used in the food field by utilizing characteristics such as low sweetness, low energy, and non-cariogenic properties, and are also in high demand in the cosmetics field by utilizing moisturizing properties. If a material having chirality can be provided, its utility value is extremely high.

  The specific embodiments and the following examples made in the section of the best mode for carrying out the invention described above merely clarify the technical contents of the present invention, and only such specific examples. It is not to be construed as limiting in a narrow sense, and those skilled in the art can make modifications within the spirit of the present invention and the scope of the appended claims.

  EXAMPLES The present invention will be described more specifically with reference to the following examples. However, these are merely examples and do not limit the scope of the present invention.

[Example 1: Culture of Pseudozyma tsukubaensis JCM 10324 strain]
a) Pseudozyma tsukubaensis JCM 10324 strain stored in a storage medium (malt extract 3 g / L, yeast extract 3 g / L, peptone 5 g / L glucose 10 g / L, agar 30 g / L), glucose 20 g / L, yeast One platinum loop is inoculated into a test tube containing 1 mL of extract, sodium nitrate 0.3 g / L, potassium dihydrogen phosphate 0.3 g / L, and magnesium sulfate 0.3 g / L. Perform shaking culture at 30 ° C., and then b) 1 mL of the obtained bacterial cell culture solution with a predetermined amount of soybean oil and yeast extract 1 g / L, sodium nitrate 0.3 g / L, potassium dihydrogen phosphate 0.3 g / L, and inoculated into a Sakaguchi flask containing 20 mL of a liquid medium having a composition of magnesium sulfate 0.3 g / L, and cultured at 30 ° C. with shaking.
The following tests were performed using the bacterial cell culture solution obtained by each culture of a) and b).

[Example 2: Confirmation of glycolipid production ability of Pseudozyma tsukubaensis JCM 10324 strain]
After culturing a) for 1 day, culturing b) was performed for 7 days, and the culture solution was collected. Using this, production of biosurfactant of Pseudozyma tsukubaensis JCM 10324 strain was confirmed by thin layer chromatography. As the developing solvent, chloroform: methanol: 7N aqueous ammonia = 65: 15: 2 was used, and as the indicator, an anthrone sulfate reagent that colored the glycolipid to blue-green was used. As a MEL standard, Pseudozyma antarctica KM-34 (FERMP-20730) strain was cultured in a soybean oil-added medium, and a purified preparation from which impurities such as raw oils and fats were removed was used. MEL-A to D in the MEL standard each represent a compound represented by the above general formula (4).

  The result is shown in FIG. According to the figure, it was found that the Pseudozyma tsukubaensis JCM 10324 strain produces a glycolipid that seems to be MEL-B.

[Example 3: Production of the same lipid in MEL production medium]
Using Pseudozyma tsukubaensis JCM 10324 strain, a) was cultured for 1 day, and then b) was cultured for 7 days. Thereafter, the culture broth was collected, the ethyl acetate-soluble component in the culture broth was purified, and the produced MEL was detected by high performance liquid chromatography. As a comparative example, a culture solution of Pseudozyma antarctica KM-34 (FERMP-20730) strain cultured using soybean oil as a carbon source was similarly detected by high performance liquid chromatography.

  The result is shown in FIG. According to FIG. 2, it can be seen that when Pseudozyma tsukubaensis JCM 10324 strain is cultured, a glycolipid whose peak can be confirmed at the same retention time as MEL-B can be obtained.

[Example 4: Cultivation of Pseudozyma crassa CBS 9959 strain and confirmation of MEL production ability]
In contrast to the method described in Example 1, Pseudozyma crassa CBS 9959 strain was used and the temperature was set to 25 ° C., and the culture was performed in the same manner. After the culture of a) was carried out for 1 day, the culture broth after the cultivation of b) was carried out for 7 days was collected and used in the same manner as described in Example 2 for the biosynthesis of Pseudozyma crassa CBS 9959 strain. Surfactant production was confirmed by thin layer chromatography.

  The result is shown in FIG. According to this, it was found that the Pseudozyma crassa CBS 9959 strain produced a glycolipid having a lower Rf value little by little than the known MEL (MEL-A to C).

[Example 5: Structural analysis of MEL produced by Pseudozyma tsukubaensis JCM 10324]
First, NMR analysis of the sugar skeleton was performed. The glycolipid obtained in Example 2 was isolated and purified by a known separation method using silica gel column chromatography, and ¹ H-NMR analysis was performed using deuterated chloroform (CDCl ₃ ) as a solvent. For comparison, Pseudozyma antarctica KM-34 (FERMP-20730) strain was cultivated, produced, isolated and purified, and the conventional MEL-B was measured in the same manner.

  The results are shown in FIG. As shown in the figure, it was found that the glycolipid produced by Pseudozyma tsukubaensis JCM 10324 strain was MEL-B. In addition, the mannose 1 'position (H-1' in the figure) is shifted in a low magnetic field from 4.73 ppm to 4.76 ppm, and in the conventional MEL, the erythritol 4-position proton (3.8 ppm, 4 .0 ppm) was confirmed to be greatly shifted into one (3.9 ppm). This is due to It is in complete agreement with the description of Non-Patent Document 7 reported by Crich et al., And proves that erythritol derived from MEL produced by Pseudozyma tsukubaensis JCM 10324 is bound in the opposite direction to conventional MEL. It is.

<Synthesis and structural analysis of 1-O-ME>
Furthermore, in order to compare the sugar skeleton structures in more detail, sugar chains (mannosyl erythritol; ME) were synthesized by cleaving side chain fatty acids by alkaline hydrolysis. MEL (680 mg) obtained in Example 6 was dissolved in methanol (10 mL), sodium methoxide (20 mg) was added, and the mixture was stirred at room temperature for 1 hr. After completion of the reaction, a cation exchange resin (Dowex H foam; 1 g) was added, and the mixture was further stirred for 15 minutes. After removing the resin by filtration, methanol was removed by an evaporator. A small amount of water (1 mL) and ethyl acetate (10 mL) were added to the resulting residue, and the fatty acid and acetic acid cleaved by the reaction were extracted and removed into the ethyl acetate phase. About the aqueous phase containing a sugar chain, the sugar chain (mannosyl erythritol; ME) was collect | recovered by performing recrystallization operation in 90% ethanol aqueous solution. By the above operation, sugar chain crystals were not obtained in this reaction, and a colorless transparent oily compound was obtained as a precipitate (257 mg).

  On the other hand, for conventional MEL obtained by culturing the Pseudozyma antarctica KM-34 (FERMP-20730) strain used as the MEL preparation in Example 1, sugar chains were recovered by the same operation. By this operation, a sugar chain (4-O-ME) synthesized from conventional MEL was obtained as white needle crystals (224 mg).

Each obtained ME was subjected to ¹ H, ¹³ C-, and various two-dimensional NMR analysis using heavy water (D ₂ O) as a solvent.

  As a result, as shown in FIG. 5, only the erythritol 4-position proton showed a peak shift (H-4a: 3.85 ppm → 3.89 ppm, H-4b: 4.12 ppm → 4.0 ppm). M. Kurz et al. Describe the detailed structure of 4-O-β-mannopyranosyl-D-erythritol (described as 1-O-β mannopyranosyl-L-erythritol in the literature) prepared from ustipid, which has the same structure as conventional MEL. (J. Antibiot., 56, 91-101 (2003)), where the chemical shift of the 4-position proton of the conventional ME is H-4a: 3.76 ppm, H-4b: 4.09 ppm It is described. Thus, even in the known literature, it has been proposed that the conventional ME (and MEL) has a large erythritol 4-position proton divided into two, and the MEL of the present invention has 1-linked erythritol bound in the opposite direction. It was shown that the conventional MEL having O-β-mannopyranosyl-D-erythritol in the sugar skeleton structure is a novel MEL having an optical isomer relationship. Each chemical shift is summarized in Table 1.

<Measurement of optical rotation of 1-O-ME>
Subsequently, the optical rotation was measured about said ME. From the MEL obtained by culturing each of Pseudozyma antarctica KM-34 (FERMP-20730) strain and Pseudozyma tsukubaensis JCM 10324 strain, ME was synthesized by alkaline hydrolysis according to the above and dissolved in distilled water to make a 1% aqueous solution. did. About each aqueous solution, the optical rotation was measured using the polarimeter (JASCO digital digital polarimeter DIP370 type | mold), and the specific rotation of each ME was calculated | required.

As a result, the specific rotation of ME derived from Pseudozyma antarctica KM-34 (FERMP-20730) is [α] _D = −35.2 °, while the specific rotation of ME derived from Pseudozyma tsukubaensis JCM 10324 is [α ] _D = −39.6 °. That is, it is shown that the chirality of the sugar skeleton (ME) of MEL produced from each strain is different. It was proved that.

<State observation of 1-O-ME>
Conventional ME derived from Pseudozyma antarctica KM-34 (FERMP-20730) was obtained as white needle crystals by the above synthesis and recovery operation (recrystallization operation in 90% ethanol). As a result of the melting point measurement, it was confirmed that the melting point was 156.9 ° C. On the other hand, ME derived from the Pseudozyma tsukubaensis JCM 10324 strain of the present invention was obtained as a colorless, transparent, oily compound without crystals obtained by the recrystallization operation described above. The obtained oily ME cannot be recovered as a powdery compound even by freeze-drying or reprecipitation into an insoluble solvent (alcohols, acetone, etc.), and as a result, the melting point cannot be measured. It was.

  As described above, it was shown that the three-dimensional structure of the molecules was different between the two, and the crystallinity was different. As described above, the 1-O-ME of the present invention is presumed to have a higher hygroscopicity than the conventional 4-O-ME, which is very useful when used for cosmetics such as skin care as a moisturizing / wetting agent. Is advantageous.

  From the above results, the MEL produced by the Pseudozyma tsukubaensis JCM 10324 strain obtained in Example 2 is MEL-B, and further, 1- (6′-acetyl) is in the optical isomer relationship with the conventional MEL-B. -2 ', 3'-di-O-alka (ke) noyl-β-D-mannopyranosyl-) meso-erythritol.

[Example 6: Structural analysis of MEL produced by Pseudozyma crassa CBS 9959 strain]
The glycolipid produced by the Pseudozyma crassa CBS 9959 strain obtained in Example 4 was also isolated and purified in the same manner as in Example 5, and ¹ H-NMR analysis was performed for all three types of glycolipids. Comparison with types MEL-A-C.

  As a result, as shown in FIG. 6, the three types of glycolipids produced by the Pseudozyma crassa CBS 9959 strain correspond to MEL-A to C, respectively, and in the conventional MEL, the erythritol 4-position proton peak is roughly divided into two. However, it was confirmed that they were shifted together. Therefore, it was proved that the Pseudozyma crassa CBS 9959 strain produces optical isomers of MEL-A to C each having erythritol bound in the opposite direction to that of the conventional MEL.

[Example 7: Comparison of liquid crystal forming ability]
The MEL produced by the Pseudozyma tsukubaensis JCM 10324 strain obtained in Example 2 and the conventional MEL produced by the Pseudozyma antarctica KM-34 (FERMP-20730) strain were compared for liquid crystal forming ability by the water intrusion method. As a result, as shown in FIG. 7 and FIG. 8, the MEL derived from Pseudozyma tsukubaensis JCM 10324 has the ability to form a lamellar phase in a very wide concentration range compared to the conventional MEL, and the liquid crystal forming ability. It was shown to be an extremely excellent biosurfactant.

[Example 8: Production of triacyl MEL by culture of Pseudozyma tsukubaensis JCM 10324 strain]
0.2 ml of P. tsukubaensis frozen stock was inoculated into a 20 ml YM seed medium / 500 ml Sakaguchi flask and cultured overnight at 26 ° C. and 180 rpm to obtain a seed seed. 0.2 ml of the inoculum was again inoculated into a 20 ml YM seed medium / 500 ml Sakaguchi flask and cultured overnight at 26 ° C., 180 rpm, and used as an inoculum. 20 ml of the inoculum was inoculated into 2 L of YM medium / 5 L Jar and cultured at 26 ° C. and 300 rpm (1/4 VVM, 0.5 L air / min) for 8 days. The culture solution was centrifuged at 7,900 rpm for 60 min at 4 ° C. to separate the cells (including MEL-B) and the supernatant. 80 ml of ethyl acetate was added to each of the bacterial cell fractions, stirred up and down so that the bacterial cells were sufficiently suspended, and then centrifuged at 7,900 rpm for 30 minutes at 4 ° C. An equal amount of saturated saline was added to the obtained supernatant and stirred to obtain an ethyl acetate layer. An appropriate amount of anhydrous sodium sulfate was added to the ethyl acetate layer and allowed to settle for 30 minutes, and then evaporated to obtain a glycolipid.

[Example 9: NMR analysis of triacyl MEL produced by Pseudozyma tsukubaensis JCM 10324 strain]
The glycolipid obtained in Example 8 was isolated and purified by a known separation method using silica gel column chromatography to obtain 50 g of MEL-B and 1.5 g of triacyl MEL-B. The triacyl MEL-B fraction was analyzed by ¹ H-NMR analysis using deuterated dimethyl sulfoxide (DMSO-d ₆ ) as a solvent in the same manner as in Example 5. The result is shown in FIG. As shown in the figure, it was confirmed that triacyl MEL-B produced by P. tsukubaensis JCM 10324 strain was bound in the opposite direction to conventional MEL.

For comparison, Pseudozyma hubeiensis was cultured and produced, and 45 g of MEL-C and 1.3 g of triacyl MEL-C were isolated and purified using silica gel column chromatography in the same manner as described above. This triacyl MEL-C was similarly subjected to ¹ H-NMR analysis using deuterated dimethyl sulfoxide (DMSO-d ₆ ) as a solvent. As a result, as shown in FIG. 10, MEL-C produced by Pseudozyma hubeiensis confirmed that erythritol was bound in the same direction as conventional MEL.

[Example 10: Lipid domain analysis of MEL-B produced by Pseudozyma tsukubaensis JCM 10324 strain]
After separating MEL-B produced by Pseudozyma tsukubaensis JCM 10324 by high-performance liquid chromatography using a reversed-phase column, mass spectrometry is performed (LC-MS analysis) to confirm the fatty acid structure of the lipid domain. did. As a result, as shown in FIG. 11, it was confirmed that a fatty acid having 8 carbon atoms was added to one hydroxyl group of mannose and a fatty acid having 10 to 14 was added to the other hydroxyl group.

  As a comparative object, LC-MS analysis was similarly performed for triacyl MEL-C produced by culturing Pseudozyma hubeiensis, isolated and purified. As a result, as shown in FIG. 12, it was confirmed that fatty acids having 6 carbon atoms were mainly added to one hydroxyl group of mannose and fatty acids having 8 to 16 were added to the other hydroxyl group.

  The HPLC analysis conditions are as follows. HPLC apparatus: Agilent 100, column: Imtakt Cadenza CD-C18 2 × 150 mm, mobile phase: A 0.1% formic acid, B acetonitrile, 0 min (50% B) -20 min (98% B) -30 min (98% B), flow rate: 0.2 ml / min, column temperature: 40 ° C., injection volume: 3 μl. MS conditions are as follows. MS equipment: BRUKER DALTONICS esquire 3000 Plus, ionization method: ESI positive.

[Example 11: Structural analysis of MEL]
Furthermore, various ^{NMR (1 H, 13 C,} 1 H- 1 H COSY, HMQC, HMBC) was measured and analyzed the structure of the MEL detail. In order to simplify the structural analysis, 40 g / L of oleic acid and glucose were added in place of soybean oil as carbon sources, and the remaining conditions were produced in the same manner as in Example 4. MEL-A produced by isolated and purified P. crassa was used. ¹ H-NMR spectrum and ¹ H- ¹ H COZY spectrum are shown in FIGS. 13 and 14, respectively.

  In the COZY spectrum of FIG. 14, the abc correlation was clearly shown. c was confirmed to be an ester bonded to the 2'-position from the results of HMBC spectrum measurement, and this showed that the fatty acid ester at the 2'-position was a C4 butanoyl group. In addition, three peaks were detected in the vicinity of 2.1 ppm, and it was also confirmed that each was a peak derived from an acetyl group bonded to the 2 ', 4', 6'-position.

  To summarize the above, MEL-A produced by P. crassa is erythritol bonded in the opposite direction to conventional MEL as shown in the structural formula shown in FIG. 13, and is acetyl group or butanoyl group at the 2′-position. It was confirmed that the MEL had a structure in which a fatty acid ester group was bonded to the 3′-position. The integrated value of the peak showed that the ratio of MEL having an acetyl group at the 2'-position to MEL having a butanoyl group was about 60:40.

  Subsequently, the side chain fatty acid composition of the obtained MEL was analyzed by the following procedure. About 10 mg of MEL was weighed in a test tube with a lid, 1 mL of 5% hydrochloric acid methanol reagent was added, and the fatty acid portion was hydrolyzed by heating at 80 ° C. Two hours later, 1 mL of water was added to stop the reaction, and 1 mL of hexane was added to extract the fatty acid methyl ester generated by the reaction into the hexane phase. The hexane phase containing the fatty acid methyl ester thus obtained was subjected to GC / MS analysis, whereby the composition analysis of the fatty acid chain bonded to MEL was performed. The results are shown in Table 2. In this analysis, only fatty acid chains with C6 or higher are detected.

  As a result of analysis, the MEL obtained above was mainly composed of C14 fatty acid, about 65% of the total, and then C16 fatty acid about 24%. Since only the C2 or C4 ester that cannot be detected by this measurement is bonded to the 2'-position, the above fatty acid composition is considered to match the fatty acid composition ratio bonded to the 3'-position as it is.

Furthermore, the molecular weight of the MEL was measured by MALDI-TOF / MS measurement. The MS spectrum of MEL-A is shown in FIG. As a result of MS analysis, pseudo-molecular ion [M + Na] ⁺ (z / m) 641.8 or 669.9 was detected. The former is presumed to be a C14: 1 fatty acid and an acetyl group, and the latter is a C14: 1 fatty acid and a butanoyl group, or MEL-A in which a C16: 1 fatty acid and an acetyl group are bonded.

  Summarizing the above NMR measurement, fatty acid composition analysis, and molecular weight measurement results, the main component of MEL-A produced by P. crassa is 1- (2 ′, 4 ′, 6 ′ shown in the following general formula (5). -Triacetyl-3'-O-alka (ke) noyl-β-D-mannopyranosyl-) meso-erythritol, or 1- (4 ′, 6′-diacetyl-2′-O— represented by the general formula (6) Butanoyl-3′-O-alka (ke) noyl-β-D-mannopyranosyl-) meso-erythritol has a structure (the 3′-position alkanoyl group is C14, C16 as shown in the above fatty acid composition analysis results. Or a saturated or unsaturated fatty acid ester of C18). Similarly, it was confirmed that MEL-B and MEL-C were structures in which the acetyl group at the 4'-position or 6'-position was removed from the above structure. MELs having these structures are all compounds that have not been reported so far, and are extremely difficult to synthesize by general chemical synthesis methods.

[Example 12: 4-O-ME and 1-O-ME skin moisturizing effect]
In order to evaluate the skin moisturizing effect due to the difference in molecular chirality between 4-O-ME and 1-O-ME, an aqueous solution containing the above saccharide is applied to the skin, and the conductivity of the skin is measured. Comparison of water holding capacity was performed. A 1% aqueous solution of 4-O-ME and 1-O-ME synthesized by the method of Example 5 and pure water were prepared and applied to the inner skin of the forearm at 10 μL / cm ² . A comparison was made by measuring the conductivity (electric resistance) between 1 cm of the coated part immediately after application, 10 minutes, 30 minutes, and 60 minutes using SANWA Digital Multimeter. Evaluation was the average of 6 samples. FIG. 16 shows the change in electrical resistance with time.

  As shown in FIG. 16, when water and a 1% 4-O-ME aqueous solution were applied, the resistance value greatly increased with the passage of time and approached the state of dry skin. On the other hand, when a 1% 1-O-ME aqueous solution was applied, the initial resistance value did not increase significantly from other samples, but the resistance value gradually increased over time. After 30 minutes, 60 minutes Later, the difference in resistance value widened, indicating that there was a difference in the amount of water retained in the skin. That is, it was shown that 1-O-ME is superior in water retention capacity compared to 4-O-ME.

  It is presumed that the ability to retain water within a molecule or between molecules is increased due to the difference in the orientation of hydroxyl groups due to the different binding directions of erythritol. As described in Example 5, it was confirmed that 1-O-ME has high water absorption of crystals and is in a state where water can be easily retained.

  The MEL according to the present invention has a completely different structure of chirality in which erythritol is ether-bonded to mannose in the opposite direction to the conventional MEL, and the self-assembly characteristics including the liquid crystal forming behavior are greatly different from those of the conventional MEL. Different. Because of these differences in physical properties, it is expected to develop new physiological activities that are not found in conventional types. Therefore, as in conventional MEL, it is widely used in detergent applications, food industry, chemical industry, environmental fields, etc. Of course, it is expected that it will contribute greatly to the expansion of applications, particularly in the pharmaceutical and cosmetic industries.

In addition, the ME described in this specification has a completely different structure of chirality in which erythritol is ether-bonded to mannose in the opposite direction to the conventional ME, so that the physiological function is significantly different from that of the conventional ME. . Therefore, it is expected to be used as a functional basic substance in the pharmaceutical, cosmetic industry, food industry, chemical industry, etc. by utilizing the difference in crystallinity and water retention.

FIG. 4 is a view showing the results of thin layer chromatography on the culture of Pseudozyma tsukubaensis JCM 10324 strain in Example 2. FIG. 4 is a diagram showing the results of high-performance liquid chromatography analysis of a culture of Pseudozyma tsukubaensis JCM 10324 strain in Example 3. FIG. 6 is a view showing the results of thin layer chromatography on a culture of Pseudozyma crassa CBS 9959 strain in Example 4. Enlarged view of the sugar skeleton part (3.4 to 5.7 ppm) in the ¹ H-NMR spectrum of MEL produced by Pseudozyma tsukubaensis JCM 10324 and Pseudozyma antarctica KM-34 (FERMP-20730) obtained in Example 5. ). Enlargement of the sugar skeleton in the ¹ H-NMR spectrum of mannosylerythritol synthesized using MEL produced by Pseudozyma tsukubaensis JCM 10324 and Pseudozyma antarctica KM-34 (FERMP-20730) obtained in Example 5 as a starting material It is a figure (3.3-4.2 ppm). It is an enlarged view (3.4-5.7 ppm) of the sugar skeleton part in the ¹ H-NMR spectrum of MEL which Pseudozyma crassa CBS 9959 strain | stump | stock obtained in Example 6 produces. In Example 7, it is a figure which shows the result of having performed the polarizing microscope observation about the liquid crystal formation ability by the water penetration | invasion method regarding MEL which Pseudozyma tsukubaensis JCM10324 strain and Pseudozyma antarctica KM-34 (FERMP-20730) strain produce. In Example 7, it is a figure which shows the result of having performed the phase-contrast microscope observation about the liquid crystal formation ability by the water penetration | invasion method regarding MEL which Pseudozyma tsukubaensis JCM 10324 strain and Pseudozyma antarctica KM-34 (FERMP-20730) strain produce. . It is a ¹ H-NMR spectrum of the triacyl MEL which the Pseudozyma tsukubaensis JCM10324 strain | stump | stock obtained in Example 8 and Example 9 produces, and the enlarged view (3.4-5.7 ppm) of a sugar skeleton part. FIG. 3 is a ¹ H-NMR spectrum of a triacyl MEL produced by Pseudozyma hubeiensis obtained in Example 9 and an enlarged view (3.0 to 5.7 ppm) of a sugar skeleton. It is a figure which shows the lipid domain analysis result by HPLC (ODS) -MS analysis of MEL which Pseudozyma tsukubaensis JCM10324 strain | stump | stock obtained in Example 8 and Example 9 produces. It is a lipid domain analysis result by HPLC (ODS) -MS analysis of the triacyl MEL which Pseudozyma hubeiensis produced in Example 9 produces. 2 is a diagram showing a ¹ H-NMR spectrum of MEL-A produced by Pseudozyma crassa CBS 9959 strain obtained in Example 6. FIG. It is an enlarged view (0.7-2.5 ppm) of a lipid part in the ¹ H- ¹ H COZY spectrum of MEL-A which Pseudozyma crassa CBS 9959 strain | stump | stock obtained in Example 6 produces. It is a figure which shows the MALDI-TOF / MS spectrum which measured the molecular weight of MEL-A which Pseudozyma crassa CBS 9959 strain | stump | stock obtained in Example 6 produced. In Example 12, it is a figure which shows the graph which followed the time-dependent change of the electrical resistance of the skin surface in order to compare the water retention amount of the skin after sample application.

Claims (5)

A mannosyl erythritol lipid having a structure represented by the following general formula (1):
(In the formula (1), the substituent R ¹ may be the same or different and is an aliphatic acyl group having 4 to 24 carbon atoms, and the substituent R ² may be the same or different and represents hydrogen or an acetyl group. (However, the two substituents R ² are not both acetyl groups . ) The substituent R ³ represents hydrogen or an aliphatic acyl group having 2 to 24 carbon atoms, provided that both substituents R ¹ have 12 carbon atoms. Except that the substituent R ² is both an acetyl group and the substituent R ³ is hydrogen.) In the general formula (1), one of the substituents R ² is an acetyl group, mannosylerythritol lipid according to claim 1 and the other is characterized by a hydrogen. ^3. The mannosyl erythritol lipid according to claim 1 or 2, wherein the substituent R3 in the general formula (1) is an aliphatic acyl group having 2 to 24 carbon atoms.   The mannosyl erythritol lipid according to any one of claims 1 to 3, wherein the mannosyl erythritol lipid is produced by a microorganism. Culturing a microorganism belonging to the genus Pseudozyma and having the ability to produce mannosyl erythritol lipid, and producing a mannosyl erythritol lipid having a structure represented by the following general formula (1) :
A method for producing mannosyl erythritol lipid, wherein the microorganism is Pseudozyma tsukubaensis or Pseudozyma crassa .
(In the formula (1), the substituent R ¹ may be the same or different and is an aliphatic acyl group having 4 to 24 carbon atoms, and the substituent R ² may be the same or different and represents hydrogen or an acetyl group. The substituent R ³ represents hydrogen or an aliphatic acyl group having 2 to 24 carbon atoms.