Method for producing aromatic alcohol compounds

Abstract

To provide a method for producing an aromatic alcohol compound by reducing a carbonyl group of an aromatic carbonyl compound with lactic acid bacteria and a processed product thereof.SOLUTION: This invention has been completed with the findings that reacting an aromatic carbonyl compound with lactic acid bacteria and a processed product thereof can produce an aromatic alcohol compound.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for producing an aromatic alcohol compound using lactic acid bacteria, and the like.

Background Art

[0002] Non-Patent Document 1 describes that 6-gingerol, which is one of the aromatic carbonyl compounds, is converted into (3R,5S)-6-gingerdioneol and (3S,5S)-6-gingerdioneol, which are aromatic alcohol compounds, by the metabolism of cancer cells or mice, and that their metabolites induce cytotoxicity in cancer cells.

[0003] In addition, Patent Document 1 describes that rhododendrol, which is one of the aromatic alcohol compounds, is isolated and identified as a component showing a protective effect against liver damage, and is converted and produced from 4-(p-hydroxyphenyl)-2-butanone, which is one of the aromatic carbonyl compounds, by the action of yeast.

[0004] Although aromatic alcohol compounds are useful as intermediates for pharmaceuticals, agricultural chemicals, etc., many of them are difficult to produce by chemical synthesis, and a simpler production method has been demanded.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Non-Patent Documents

[0006]

Non-Patent Document 1

[0007] The object of the present invention is to provide a method for producing aromatic alcohol compounds by reducing the carbonyl group of an aromatic carbonyl compound using lactic acid bacteria and its processed products. [Means for solving the problem]

[0008] The inventors discovered that aromatic alcohol compounds can be produced by reacting aromatic carbonyl compounds with lactic acid bacteria and their processed products, and thus completed the present invention.

[0009] In other words, the present invention relates to the following embodiments [1] to [3]. [1] General formula (I) [ka] (In the formula, R1 represents a hydrogen atom or a hydroxyl group, R2 represents a hydrogen atom, a hydroxyl group, or a methoxy group, R3 represents a hydrogen atom, an alkyl group, an alkenyl group, a hydroxyalkyl group, a carbonylalkyl group, or an acetoxyalkyl group, and n represents an integer from 0 to 2.) Aromatic carbonyl compounds represented by general formula (II) [ka] (In the formula, R1, R2, R3, and n have the same meanings as above.) A method for producing an aromatic alcohol compound, characterized by reacting a microorganism belonging to the genus Lactobacillus, which has the ability to reduce an aromatic alcohol compound represented by the formula (II), with a processed product thereof, to produce an aromatic alcohol compound represented by the general formula (II). [2] A method for producing an aromatic alcohol compound according to [1], wherein the aromatic carbonyl compound is a paradol and the aromatic alcohol compound is a dihydroparadol. [3] An antioxidant containing dihydroparadol as the active ingredient. [Effects of the Invention]

[0010] This invention demonstrates that aromatic alcohol compounds can be easily produced by reacting aromatic carbonyl compounds with lactic acid bacteria or a processed product thereof, and provides a method for producing aromatic alcohol compounds that can be mass-produced.

[0011] Furthermore, it has been found that the aromatic alcohol compounds of the present invention possess excellent antioxidant activity and can be used as antioxidants. [Brief explanation of the drawing]

[0012] [Figure 1] The concentrations of 6-gingerol, (3R,5S)-6-zingerdiol, and (3S,5S)-6-zingerdiol per unit of solid content before and after fermentation by lactic acid bacteria are shown. [Figure 2] The concentrations of 6-gingerol, (3R,5S)-6-zingerdiol, and (3S,5S)-6-zingerdiol per unit of solid content before and after fermentation by lactic acid bacteria are shown. [Modes for carrying out the invention]

[0013] The manufacturing method of the present invention is based on general formula (I) [ka] Aromatic carbonyl compounds represented by general formula (II) [Chemical formula] A method for producing an aromatic alcohol compound represented by the general formula (II) by allowing a microorganism belonging to the genus Lactobacillus or a processed product thereof, which has the ability to reduce an aromatic carbonyl compound represented by the general formula (I), to act thereon.

[0014] In the above formula, R1 is a hydrogen atom or a hydroxy group, R2 is a hydrogen atom, a hydroxy group or a methoxy group, R3 is a hydrogen atom, an alkyl group, an alkenyl group, a hydroxyalkyl group, a carbonylalkyl group or an acetoxyalkyl group, n represents an integer of 0 to 2, and 0 or 2 is preferred. The alkyl group of R3 is preferably a linear alkyl group having 1 to 14 carbon atoms. The alkenyl group of R3 is preferably a linear alkenyl group having 1 to 14 carbon atoms, and it is more preferably that C1 and C2 are bonded by a double bond. The hydroxyalkyl group, carbonylalkyl group or acetoxyalkyl group of R3 is preferably a linear alkyl group having 1 to 14 carbon atoms which is substituted, and the position of substitution is not particularly limited, but an alkyl group in which the hydrogen atom at C2 is substituted by a hydroxy group, a carbonyl group or an acetoxy group is preferred. The number of carbon atoms of R3 is more preferably 1, 5, 7, 9 or 11, and even more preferably 1 or 7.

[0015] The microorganism used in the present invention is not particularly limited as long as it is a microorganism belonging to the genus Lactobacillus having the ability to reduce the aromatic carbonyl compound represented by the general formula (I) to the aromatic alcohol compound represented by the general formula (II), but heterofermentative lactic acid bacteria are preferred, and Lactobacillus brevis, Lactobacillus fermentum, Lactobacillus reuteri, Lactobacillus kefiri or Lactobacillus fructivorans are preferred, and one kind or two or more kinds can be used.

[0016] The culture medium for culturing the microorganisms used in the present invention is not particularly limited as long as it contains components that allow the microorganisms to grow, and general culture medium components can be used. Examples include those containing carbon sources, nitrogen sources, inorganic substances, micronutrients, etc., and either synthetic or natural culture media can be used. Examples of carbon sources include glucose, sucrose, lactose, trehalose, glycerin, sorbitol, molasses, etc. Examples of nitrogen sources include inorganic salts such as ammonium chloride, ammonium nitrate, ammonium sulfate, ammonium citrate, ammonium phosphate, amino acids such as DL-alanine, L-glutamic acid, peptone, meat extract, yeast extract, malt extract, corn steep liquor, milk protein, soy protein, etc. Examples of inorganic substances include calcium, sodium, potassium, magnesium, manganese, iron, zinc, etc. Furthermore, surfactants such as Tween 80, emulsifiers such as polyglycerin fatty acid esters, and oils and fats such as olive oil may be used.

[0017] Culturing can be carried out by sterilizing a liquid medium containing the aforementioned culture medium components, inoculating the microorganisms, and culturing by standing or shaking. However, it is preferable to cultivate under aerobic conditions by aeration, shaking, stirring, etc. The culture temperature can be exemplified as 10 to 50°C, preferably 15 to 40°C, the culture time can be exemplified as 1 to 120 hours, preferably 2 to 96 hours, and more preferably 6 to 72 hours, and the pH can be exemplified as 2.0 to 8.5, preferably 3.0 to 8.0. The pH may be adjusted within the above range during cultivation. Sodium hydroxide, ammonia, etc. can be used to adjust the pH, but it is preferable to use calcium compounds such as calcium carbonate, as they gradually dissolve as the culture solution becomes acidic during cultivation, mitigating the decrease in pH and allowing for pH adjustment, thereby suppressing the inhibition of lactic acid bacteria growth due to the decrease in pH.

[0018] As a method for producing the aromatic alcohol compound of the present invention, an aromatic carbonyl compound represented by general formula (I) can be converted to an aromatic alcohol compound represented by general formula (II) using a microorganism obtained by culture or a processed product thereof. This method can be carried out using any of the processed products of microorganisms, such as a microbial culture, bacterial cells obtained by culture, bacterial cell lysates obtained by crushing the bacterial cells, or cell-free extracts. An example is a method in which the aromatic carbonyl compound is added to a microbial culture and reacted. The aromatic carbonyl compound can be added to the culture medium before, during, or after culture, and may be added continuously, or culture and reaction may be carried out simultaneously. Another example is a method in which bacterial cells separated from the culture by centrifugation or the like are resuspended in a buffer solution, water, etc., and the aromatic carbonyl compound is added and reacted. During the reaction, a carbon source such as glucose or sucrose may be added as an energy source. Furthermore, an example is a method in which processed products of microorganisms, such as bacterial cell lysates or cell-free extracts, are brought into contact with the aromatic carbonyl compound and reacted. Bacterial cells immobilized by known methods can also be used.

[0019] When the reaction solution is a liquid in which an aromatic carbonyl compound reacts with a microorganism or its processed product, the amount of aromatic carbonyl compound per unit of solids in the solution at the start of the reaction is preferably 0.1% by weight or more, more preferably 0.2 to 50% by weight, and even more preferably 0.4 to 40% by weight. The culture solution or fermented product and the reaction solution may be synonymous, and the amount of aromatic carbonyl compound in the culture medium at the start of cultivation may be the same concentration as in the reaction solution. Furthermore, the aromatic carbonyl compound may be derived from natural products or synthetic products. For example, if the aromatic carbonyl compound is contained in a plant, a plant extract obtained by supercritical fluid extraction, steam distillation, solvent extraction, etc., may be used.

[0020] The aromatic carbonyl compound to be added may be added directly to the reaction solution, but it is preferable to emulsify it so that it disperses well in the solution, and it may also be added as an emulsified powder. The emulsifier is not particularly limited as long as it is a component that has emulsifying ability, but examples include gums such as acacia gum, ghati gum, and xanthan gum, sodium starch octenyl succinate, casein, glycerin fatty acid esters, polyglycerin fatty acid esters, sucrose fatty acid esters, lecithin, enzyme-treated lecithin, etc., and one or more types may be used, and an emulsion of the aromatic carbonyl compound and emulsifier may be added, or the aromatic carbonyl compound and emulsifier may be added to the reaction solution.

[0021] The reaction conditions can be exemplified by a temperature of 10 to 60°C, preferably 20 to 50°C; the reaction time can be exemplified by a temperature of 1 to 120 hours, preferably 2 to 96 hours, and more preferably 6 to 72 hours; the pH can be exemplified by a temperature of 2.5 to 9.0, preferably 3.0 to 8.5; the pH may be adjusted within the above range during the reaction, for example, and the pH adjusting agents exemplified for pH adjustment during cultivation can be used. The reaction may be carried out under standing conditions, but stirring is preferred, as this allows for the generation and accumulation of the aromatic alcohol compound of the present invention in the reaction solution.

[0022] The conversion rate from aromatic carbonyl compounds to aromatic alcohol compounds is preferably 10% or more, more preferably 20% or more, even more preferably 30% or more, particularly preferably 50% or more, and most preferably 80% or more. The content of aromatic alcohol compounds in the reaction solution is preferably 0.05% by weight or more, more preferably 0.1 to 50% by weight, even more preferably 0.2 to 40% by weight, and particularly preferably 0.5 to 30% by weight, based on solid content.

[0023] The reaction can be sterilized, and the sterilization conditions are not particularly limited as long as they are general methods, but heating at 60-120°C for 1-30 minutes or at 80-100°C for 5-20 minutes is preferred, for example. The product can be recovered as a liquid obtained by solid-liquid separation using filtration with nonwoven fabric, mesh, etc., centrifugation, etc., or it can be further concentrated and / or dried and used as a concentrated or dried product. Drying can be done by drum drying, air drying, spray drying, vacuum drying and / or freeze-drying, etc. Furthermore, the aromatic alcohol compounds produced by the reaction can be recovered directly from the reaction solution or by extraction with an organic solvent after separation of bacterial cells, etc., and purified products can be obtained using conventional purification methods such as distillation and column chromatography.

[0024] The aromatic alcohol compounds obtained in this invention exhibit excellent antioxidant activity and can therefore be used as antioxidants. Examples of aromatic alcohol compounds include 6-zinger diols such as (3R,5S)-6-zingerdiol and (3S,5S)-6-zingerdiol, zingerol, and 6-dihydroparadol, and these compounds can be used as antioxidants containing these compounds as active ingredients.

[0025] The aromatic alcohol compounds obtained in this invention can be added to various products to produce aromatic alcohol compound-containing products. This makes it easy to add the various functionalities of the aromatic alcohol compounds to various foods and beverages. The amount to be added to each food and beverage is not particularly limited, but is preferably 0.001 to 10% by weight, more preferably 0.01 to 5% by weight, even more preferably 0.05 to 2% by weight, and most preferably 0.1 to 1% by weight. The foods and beverages to which it is added are not particularly limited, but can be used in various foods and beverages such as beverages, foods, seasonings, functional foods, and supplements, as well as in pharmaceuticals, quasi-drugs, cosmetics, and animal feed.

[0026] The food, pharmaceutical, or quasi-drug of the present invention can be used as a functional food, pharmaceutical, or quasi-drug that can improve or prevent diseases or symptoms caused by reactive oxygen species through the antioxidant effect of aromatic alcohol compounds.

[0027] The cosmetic of the present invention can be used as a skin aging preventive agent or a whitening agent, which prevents skin aging, pigmentation, etc. caused by active oxygen due to the antioxidant action of the aromatic alcohol compound.

[0028] The feed of the present invention can be used as a feed that can improve or prevent diseases or symptoms of animals, etc. caused by active oxygen due to the antioxidant action of the aromatic alcohol compound.

Example

[0029] Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to the following examples. In the present invention, % is all by weight unless otherwise specified.

Example

[0030] (Production 1 of aromatic alcohol compound) Ginger extract powder G2 (6-gingerol content: 2.3%, manufactured by Ikeda Sugar Industry Co., Ltd.) as a gingerol-containing substance was added to MRS medium to a final concentration of 5%, and 20 g each was dispensed into test tubes and then heat-sterilized at 121 °C for 15 minutes. One platinum loop of Lactobacillus brevis NBRC3345 (Examples 1-1 and 1-2) or Lactobacillus fermentum NBRC15885 (Examples 1-3 and 1-4) was inoculated into two cooled liquid media each, and statically cultured at 30 °C for 40 hours. After completion of the culture, sterilization treatment was performed at 90 °C for 10 minutes to obtain each lactic acid bacteria fermented product.

[0031] Regarding each lactic acid bacteria fermented product obtained in Examples 1-1 to 1-4, the pH after fermentation was measured and described in Table 1, and the content of 6-gingerol was measured under the following HPLC measurement conditions 1 and shown in FIG. 1 as the concentration in the medium.

[0032] <HPLC measurement conditions 1> ·Detector: UV detector (282 nm) • Column: InertSustain C18 (inner diameter 4.6 mm, length 250 mm) Mobile phase: Gradient from 30% acetonitrile aqueous solution to 100% acetonitrile ·Flow rate: 0.8ml / min Column temperature: 40°C • Standard: 6-Gingerol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was dissolved in 95% ethanol to create a calibration curve. Should the structural formula be included? • Samples: Each sample was used after being appropriately diluted with 80% acetonitrile.

[0033] Furthermore, a comparison of the HPLC charts before and after fermentation revealed two additional peaks that appeared after fermentation, separate from 6-gingerol (retention time: around 17 minutes). These peaks (retention time: around 14 minutes for L. brevis and around 15 minutes for L. fermentum) were thought to be substances produced by fermentation. Analysis using LC / MS and NMR revealed that these substances were indeed two isomers of 6-gingerdiol: (3R,5S)-6-gingerdiol and (3S,5S)-6-gingerdiol.

[0034] For (3R,5S)-6-zingerdiol and (3S,5S)-6-zingerdiol, purified samples analyzed by NMR were used as standards, and their concentrations were calculated under the HPLC measurement conditions 1 described above. The concentrations per unit of solids in the fermented product are shown in Figure 1. The sum of (3R,5S)-6-zingerdiol and (3S,5S)-6-zingerdiol was taken as the value of 6-zingerdiol, and the 6-zingerdiol concentration per unit of solids in the fermented product is shown in Table 1. In addition, the measured concentrations of each component in the culture medium immediately before inoculation, per unit of solids before fermentation, are shown in Figure 1.

[0035] [Table 1] [Examples]

[0036] (Production of aromatic alcohol compounds 2) Following the method of Example 1, lactic acid bacteria fermented products were obtained using L. reuteri NBRC15892, L. kefiri NBRC15888, or L. fructivorans NBRC13954 (Examples 2-1, 2-2, or 2-3) under the conditions described in Table 2. 10 μL of glycerol stock was used for inoculation.

[0037] For each lactic acid bacteria fermented product obtained in Examples 2-1 to 2-3, the pH after fermentation was measured and recorded in Table 2, as in Example 1. In addition, the content of 6-gingerol, (3R,5S)-6-zingerdiol, and (3S,5S)-6-zingerdiol per unit of solid content in the fermented product was measured and shown in Figure 2. The total of (3R,5S)-6-zingerdiol and (3S,5S)-6-zingerdiol is shown in Table 2 as the 6-zingerdiol concentration per unit of solid content in the fermented product.

[0038] [Table 2]

[0039] As shown in Figures 1 and 2, in both Examples 1 and 2, culturing lactic acid bacteria in a medium containing gingerol resulted in the production of 6-gingerdiol after fermentation. In particular, L. brevis produced (3R,5S)-6-gingerdiol, and L. fermentum produced (3S,5S)-6-gingerdiol. Furthermore, the amount of 6-gingerol decreased and the amount of 6-gingerdiol increased before fermentation. [Examples]

[0040] (Production of aromatic alcohol compounds 3) Other medium components and each aromatic carbonyl compound were added to MRS medium at the final concentrations shown in Table 3 and mixed, and then the medium was prepared by heat sterilization at 121°C for 15 minutes. L.brevis NBRC12005 (Examples 3-1 to 3-4), L.reuteri NBRC15892 (Example 3-5) or L.fermentum NBRC15885 (Example 3-6) was inoculated into the cooled medium and cultured under the conditions shown in Table 3, respectively. After the cultivation was completed, sterilization treatment was performed at 90°C for 10 minutes to obtain each lactic acid bacteria ferment. The polyglycerol fatty acid ester preparation used as an emulsifier was Sansoft (registered trademark) Q-17S (manufactured by Sun Chemical Co., Ltd.). Regarding the aromatic carbonyl compound, in Example 3-1, vanillylacetone (manufactured by Fujifilm Wako Pure Chemical Corporation), in Example 3-3, vanillin (manufactured by Fujifilm Wako Pure Chemical Corporation), in Example 3-4, raspberry ketone (3-(4-Hydroxyphenyl)-2-butanone, manufactured by Tokyo Chemical Industry Co., Ltd.) was added to reach the final concentrations shown in Table 3. In Examples 3-2 and 3-5, Ginger soft SCFE 35% containing 6-gingerol (manufactured by Sabinsa Japan Corporation) was used, and in Example 3-6, Fermented Ginger Extract Powder S containing 6-paradol (manufactured by Ikeda Sugar Industry Co., Ltd.) was used, and 6-gingerol or 6-paradol was added to reach each final concentration shown in Table 3.

[0041] <HPLC measurement conditions 2> · Detector: UV detector (282 nm) · Column: InertSustain C18 (inner diameter 4.6 mm, length 250 mm) · Mobile phase: Gradient from 40% aqueous acetonitrile solution to 80% acetonitrile · Flow rate: 0.8 ml / min<00MRS medium at the final concentrations shown in Table 3 and mixed, and then the medium was prepared by heat sterilization at 121°C for 15 minutes. L.brevis NBRC12005 (Examples 3-1 to 3-4), L.reuteri NBRC15892 (Example 3-5) or L.fermentum NBRC15885 (Example 3-6) was inoculated into the cooled medium and cultured under the conditions shown in Table 3, respectively. After the cultivation was completed, sterilization treatment was performed at 90°C for 10 minutes to obtain each lactic acid bacteria ferment. The polyglycerol fatty acid ester preparation used as an emulsifier was Sansoft (registered trademark) Q-17S (manufactured by Sun Chemical Co., Ltd.). Regarding the aromatic carbonyl compound, in Example 3-1, vanillylacetone (manufactured by Fujifilm Wako Pure Chemical Corporation), in Example 3-3, vanillin (manufactured by Fujifilm Wako Pure Chemical Corporation), in Example 3-4, raspberry ketone (3-(4-Hydroxyphenyl)-2-butanone, manufactured by Tokyo Chemical Industry Co., Ltd.) was added to reach the final concentrations shown in Table 3. In Examples 3-2 and 3-5, Ginger soft SCFE 35% containing 6-gingerol (manufactured by Sabinsa Japan Corporation) was used, and in Example 3-6, Fermented Ginger Extract Powder S containing 6-paradol (manufactured by Ikeda Sugar Industry Co., Ltd.) was used, and 6-gingerol or 6-paradol was added to reach each final concentration shown in Table 3.

[0041] <HPLC measurement conditions 2> · Detector: UV detector (282 nm) · Column: InertSustain C18 (inner diameter 4.6 mm, length 250 mm) · Mobile phase: Gradient from 40% aqueous acetonitrile solution to 80% acetonitrile · Flow rate: 0.8 ml / min · Column temperature: 40°C 208> ·カラム温度:40℃ <OO00209>• Standards: Vanillylacetone (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 6-gingerol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 6-paradol (manufactured by Cosmo Bio Inc.), vanillin (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), vanillyl alcohol (manufactured by Tokyo Chemical Industry Co., Ltd.), raspberry ketone (manufactured by Tokyo Chemical Industry Co., Ltd.), and rhododenol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) were dissolved in 95% ethanol to create a calibration curve. • Samples: Each sample was used after being appropriately diluted with 80% acetonitrile.

[0042] The vanillylacetone content of Example 3-1 before and after fermentation was measured using the HPLC measurement conditions described above. Furthermore, when comparing the HPLC charts before and after fermentation, a new peak (retention time: around 6 minutes) appeared after fermentation, separate from vanillylacetone (retention time: around 7 minutes). This was considered to be a substance produced by fermentation, so the substance was purified using a C18 column and analyzed by LC / MS and NMR. The results revealed that the substance was zingerol. The purified zingerol was used as a standard, dissolved in 95% ethanol, and measured using the HPLC measurement conditions 2 described above to create a calibration curve. The concentration in the fermented product was calculated from the AREA value of the HPLC, and the conversion rate from aromatic carbonyl compounds to aromatic alcohol compounds was calculated by dividing the concentration of zingerol after fermentation by the concentration of vanillylacetone before fermentation. This is shown in Table 3.

[0043] The 6-gingerol content of Examples 3-2 and 3-5 before and after fermentation was measured under the HPLC measurement conditions described above. Furthermore, when the HPLC charts before and after fermentation were compared, (3R,5S)-6-zingerdiol (6-zingerdiol) was confirmed after fermentation in Example 3-2, and (3S,5S)-6-zingerdiol (6-zingerdiol) was confirmed after fermentation in Example 3-5. The concentrations of each 6-zingerdiol in the fermented product were calculated using the method described above, and the conversion rate from aromatic carbonyl compounds to aromatic alcohol compounds was calculated by dividing the concentration of 6-zingerdiol after fermentation by the concentration of 6-gingerol before fermentation, and this is shown in Table 3.

[0044] The vanillin content of Example 3-3 before and after fermentation was measured under the HPLC measurement conditions described above. Furthermore, when the HPLC charts before and after fermentation were compared, a new peak appeared after fermentation, and by comparing it with the standard, it was revealed that this substance was vanillyl alcohol. The concentration of vanillyl alcohol in the fermented product was calculated, and the conversion rate from aromatic carbonyl compounds to aromatic alcohol compounds was calculated by dividing the concentration of vanillyl alcohol after fermentation by the concentration of vanillin before fermentation, and this is shown in Table 3.

[0045] The raspberry ketone content of Examples 3-4 before and after fermentation was measured under the HPLC measurement conditions described above. Furthermore, a comparison of the HPLC charts before and after fermentation revealed a new peak that appeared after fermentation. By comparing this with the standard, it was determined that the substance was rhododenol. The concentration of rhododenol in the fermented product was calculated, and the conversion rate from aromatic carbonyl compounds to aromatic alcohol compounds was calculated by dividing the concentration of rhododenol after fermentation by the concentration of raspberry ketone before fermentation, and this is shown in Table 3.

[0046] The 6-parador content of Examples 3-6 before and after fermentation was measured under the above HPLC measurement conditions. Furthermore, when comparing the HPLC charts before and after fermentation, a new peak (retention time: around 29 minutes) that appeared after fermentation, separate from 6-parador (retention time: around 33 minutes), was observed. This was considered to be a substance produced by fermentation, so the substance was purified using a C18 column and analyzed by LC / MS and NMR. The results revealed that the substance was 6-dihydroparador. The purified 6-dihydroparador was used as a standard, dissolved in 95% ethanol, and measured under the above HPLC measurement conditions to create a calibration curve. The concentration in the fermented product was calculated from the AREA value of the HPLC, and the conversion rate from aromatic carbonyl compounds to aromatic alcohol compounds was calculated by dividing the concentration of 6-dihydroparador after fermentation by the concentration of 6-parador before fermentation, and is shown in Table 3.

[0047] [Table 3]

[0048] From the above, it was found that aromatic alcohol compounds can be produced by reacting aromatic carbonyl compounds with microorganisms belonging to the genus Lactobacillus, making it possible to provide a simpler method for producing aromatic alcohol compounds. [Examples]

[0049] (Antioxidant activity) Each of the following samples was diluted to approximately 2,000 ppm with 80% acetonitrile, and then further diluted to approximately 24 ppm, 18 ppm, 12 ppm, and 6 ppm with 80% ethanol as appropriate, to prepare the samples. The antioxidant activity of each sample was evaluated by measuring the DPPH radical scavenging activity using the method described below.

[0050] <Sample> • Vanillylacetone (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., purity: >98.0%) • 6-Gingerol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., standard content: 98.0+%) • 6-Gingerol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., for use in pharmacopoeia crude drug testing) • 6-Parador (manufactured by Toronto Research Chemicals, standard product) • Zingerol (purified product of the compound obtained in Example 3-1 by the following purification method) • (3R,5S)-6-Zingerdiol (purified product of the compound obtained in Example 1-1 by the following purification method) • (3S,5S)-6-Zingerdiol (purified product of the compounds obtained in Examples 1-3 by the following purification method) • 6-Dihydroparadol (purified product of the compound obtained in Examples 3-6 by the following purification method)

[0051] <Purification method> (1) Add ethyl acetate and NaCl to the lactic acid bacteria fermented product, mix, and centrifuge. (2) The ethyl acetate layer is recovered, concentrated, dissolved in acetonitrile, and used for purification. (3) Add (2) to a C18 resin column, flow an aqueous acetonitrile solution with an appropriately set concentration, and separate the components in (2). (4) During (3), sampling is performed at regular intervals for fractionation, analyzed by HPLC, and samples in which the target component is detected are selected. (5) The selected samples are concentrated, recovered with diethyl ether, and then the diethyl ether is volatilized to obtain a purified product.

[0052] <Measurement method for DPPH radical scavenging activity> Refer to the reference (edited by Shinohara et al., Food Function Research Methods, Koryu, 2000, p. 218) and measure as follows. To 50 μL of each sample appropriately diluted with 80% (w / v) ethanol, add a mixture of 50 μL of 200 mM 2-morpholinoethanesulfonic acid (MES) buffer (200 mM, pH 6.0), 50 μL of 20% ethanol, and 50 μL of 400 μM 1,1-diphenyl-2-picrylhydrazyl (DPPH) ethanol solution, mix well, and after standing for another 20 minutes, measure the absorbance at 520 nm using a microplate reader. A calibration curve is created by performing the same operation on 0 - 200 μM α-tocopherol (manufactured by Wako Pure Chemical Industries, Ltd.), and based on the obtained calibration curve, the radical scavenging activity per 1 g of each sample is calculated as the α-tocopherol equivalent amount (concentration).

[0053] When the radical scavenging activity per gram of each sample was calculated as the equivalent amount (concentration) of α-tocopherol, vanillylacetone was found to be 4,073 μmol / g, 6-gingerol 3,059 μmol / g, 6-shogaol 3,300 μmol / g, 6-paradol 3,832 μmol / g, zingerol 4,706 μmol / g, (3R,5S)-6-zingerdiol 3,807 μmol / g, (3S,5S)-6-zingerdiol 3,689 μmol / g, and 6-dihydroparadol 3,825 μmol / g. All of these samples showed excellent antioxidant activity and were found to be usable as antioxidants.

Claims

1. General formula (I) 【Chemistry 1】 (In the formula, R1 represents a hydroxyl group, R2 represents a hydrogen atom, a hydroxyl group, or a methoxy group, R3 represents a hydrogen atom, an alkyl group, an alkenyl group, a hydroxyalkyl group, a carbonylalkyl group, or an acetoxyalkyl group, and n represents an integer from 0 to 2.) Aromatic carbonyl compounds represented by the general formula (II) 【Chemistry 2】 (In the formula, R1, R2, R3, and n have the same meanings as described above.) A method for producing an aromatic alcohol compound, characterized by reacting a microorganism belonging to the genus Lactobacillus, which has the ability to reduce an aromatic alcohol compound represented by general formula (II), with a product thereof, to produce an aromatic alcohol compound represented by general formula (II).

2. A method for producing an aromatic alcohol compound according to claim 1, wherein the aromatic carbonyl compound is a paradol and the aromatic alcohol compound is a dihydroparadol.

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