JP2017074047A - Food composition containing lignan compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a food composition containing a compound having activity of inhibiting growth of cancer stem cells.SOLUTION: A food composition contains a lignan compound represented by a specific general formula which is extracted with a water/alcohol mixed solution from Eucommia leaf dry powder obtained by preferably drying and powdering Eucommia leaves, where chlorogenic acid is dimerized at a double bond site to form a cyclobutane ring structure. The food composition further contains ginger, stevia, mulberry leaves, or Perilla frutescens.SELECTED DRAWING: None

Description

  The present invention relates to a food composition containing a lignan compound, and more particularly to a food composition containing a lignan compound having growth inhibition activity of cancer stem cells.

  Cancer stem cells are cell types having the properties of stem cells contained in small amounts in tumor tissue. Since cancer stem cells are in a state of being almost dormant and not actively dividing like normal cancer cells, existing anticancer agents that target active cell activity are not effective. Cancer stem cells are self-replicating and tumorigenic, and form a tumor similar to the original tumor tissue when transferred into normal tissue, which is a major cause of cancer metastasis and recurrence. However, effective drugs that inhibit the growth of cancer stem cells have not been developed, and their development has become an important research object in cancer research.

  Traditionally, cancer stem cells have been removed from tumor tissue and used for research. However, since cancer stem cells contain only trace amounts in tumor tissues, they are not suitable for studies that require large amounts of cancer stem cells such as screening for anti-cancer cell substances. For this reason, co-inventor Professor Akihide Liang of Yokohama City University School of Medicine succeeded in establishing a cultured cell line (iCSCL-10A) with cancer stem cell properties using iPS technology. By using this cultured cell, it was possible to test the growth inhibitory activity of cancer stem cells.

  Eucommia ulmoides is a natural tree distributed mainly in Sichuan and Hunan provinces of China. Currently, Tochu Nakaha is eaten a lot as health food such as “Tochucha”, but according to an ethnographic survey in western China, it has been eaten as a tea or a bowl by ethnic minorities such as “Chinese” for a long time. Has been revealed. With regard to the maximum intake, there is a description of 20 g / day (about 100 g in terms of leaf weight) for Tochu Naka leaf extract, which suggests that there is no problem with the intake and safety within this range. In addition, because the existing species is a kind of genus and genus (Coleoptera genus Eucommia), the range of variation within the species is small, and the qualitative and quantitative bias of the components is small, which is stable from a genetic point of view. It is a material.

  Tochu Naka is known to contain iridoids and polyphenols (for example, Patent Documents 1 to 3), and several types of secondary metabolites including iridoids, phenylpropanoids, and flavonoids isolated from Tochu Naka are specified. It has been clarified in the research up to now that the anti-biological action is exhibited (for example, Non-Patent Documents 1 to 4). Pinoresinol di-O-β-d-glucopyranoside and geniposidic acid are compounds unique to Tochu Nakaba. It is known that the iridoid geniposidic acid has a high content in tochu-nakaba, and when it is absorbed into the body, it acts on the parasympathetic nerve and relaxes the muscles around the peripheral blood vessels, thereby causing a hypotensive action. It is also known that geniposidic acid suppresses an increase in cholesterol level by increasing adiponectin which acts on the reduction of visceral fat and suppression of weight gain. In addition, as chemical substances derived from Tonaka, genipin and geniposide show anti-inflammatory agents, thrombus inhibition and antitumor activity, chlorogenic acid shows antibacterial, antioxidant and antimutagenic properties, baicalein, wogonin and oroxylin A It has been reported that the flavonoids contained have antioxidative, anti-inflammatory and antiviral properties.

  In addition, Patent Document 4 discloses a phenolic dimer compound as a compound having a lignan-like structure. The compound is said to have a lipase inhibitory action.

Japanese Patent No. 4846838 Patent No. 5014320 Patent No. 5323003 JP 2012-116756 A

Isoguro et al., Studies on iridoid-related compounds. IV. Antitumor activity of iridoid aglycones. Chem. Pharm. Bull. 34: 2375-2379, 1986; Ikemoto et al., Antitumor effects of Scutellariae radix and its components baicalein, baicalin, and wogonin on bladder cancer cell lines. Urology 55, 951-955, 2000; Zhang et al., Studies on bioactivities of chlorogenic acid and its analogues. Chin. Tradit. Herbal Drags 32: 173-176, 2001 Tang et al., Simultaneous determination of ten bioactive constituents in Eucommia ulmoides leaves and Tochu tea products by high-performance liquid chromatography-diode array detector-mass spectrometry (HPLC-DAD-MS). J. Trad. Med., 25, 112 -118, 2008

  As described above, an effective drug that inhibits the growth of cancer stem cells has not yet been developed, and the development thereof is required. In view of such circumstances, an object of the present invention is to provide a food composition containing a compound having an activity of inhibiting the growth of cancer stem cells.

The inventors have found that a compound represented by the following formula (1) has an activity of inhibiting the growth of cancer stem cells, and completed the present invention. The above problems are solved by the present invention described below.
[1] A food composition containing a compound represented by the following general formula (1).
[2] A food composition comprising the compound according to [1], wherein R and R ³ are hydrogen atoms, and m and n are 0.
[3] The food composition according to [1] or [2], further comprising ginger, stevia, mulberry leaves, or egoma.

  According to the present invention, a food composition containing a compound having an activity of inhibiting the growth of cancer stem cells can be provided.

It is a schematic diagram which shows the outline | summary of 1 aspect of this invention. 2A is a diagram showing the anticancer activity test results (2D culture) of Example 4, and FIG. 2B is a diagram showing the test results of Comparative Example 1. FIG. 3A is a diagram showing the anticancer activity test results (3D culture) of Example 5, and FIG. 3B is a diagram showing the test results of Comparative Example 2. FIG. 2 is a photograph of culture media in Example 5 and Comparative Example 2.

  Hereinafter, the present invention will be described in detail. In the present invention, “to” includes values at both ends thereof. That is, the description “X to Y” means that X and Y are included.

1. Compound The compound of the present invention is represented by the formula (1). The compound is a lignan compound in which chlorogenic acid is dimerized at a double bond site to form a cyclobutane ring structure.

  In the formula, R is independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an acyl group having 2 to 6 carbon atoms. Independent means that each R may be the same or different. The same applies to other groups. In the present invention, the alkyl group includes linear and branched alkyl groups. From the viewpoint of ease of production, R is preferably a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an acyl group having 2 to 4 carbon atoms.

R ¹ and R ² are substituents on the benzene ring, and are independently a halogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkylene group having 2 to 5 carbon atoms. In the present invention, the alkylene group includes linear and branched alkylene groups. The halogen atom is preferably a fluorine atom or a chlorine atom, the alkyl group is preferably an alkyl group having 1 to 3 carbon atoms, and the alkylene group is preferably an alkylene group having 2 to 3 carbon atoms. m and n each represent the number of ^{R 1} and ^{R 2,} it is 0-3. From the viewpoint of ease of production, m and n are preferably 0 to 2, and more preferably 0.

R ³ is independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. From the viewpoint of ease of production, R ³ is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

2. Method for producing compound The compound of the present invention comprises (A) a step of extracting an extract from water or a water / alcohol mixed solvent to obtain an extract,
(B) Extracting the extract with alcohol to obtain an aqueous phase and an alcohol phase; and (C) Separating and purifying the aqueous phase by normal phase chromatography and then reverse phase chromatography. It is preferable to be manufactured. Hereinafter, each step will be described.

(1) Process A
In this step, the Nakanaka leaf is extracted with water or a water / alcohol mixed solvent. As described above, the Tochu leaf is a leaf of a plant belonging to the genus Eucommia sp. The alcohol used here is not limited as long as it dissolves in water and becomes a mixed solvent, but methanol and ethanol are preferable. The alcohol concentration is preferably 50 to 80% by weight in the mixed solvent. It is preferable that the weight ratio of the Tochu leaf and water or the water / alcohol mixed solvent is about 1: 2 to 1: 5. When water is used, the temperature is preferably about 70 to 100 ° C. In this step, the Nakanaka leaf after extraction with the water / alcohol mixed solvent may be further extracted with hot water at the above temperature.

  As the bamboo leaf, a raw leaf that has not been processed, a dry leaf obtained by drying the fresh leaf, or a dry powder obtained by powdering the dry leaf can be used. It is preferable to use a dry powder (hereinafter also referred to as “Tochu tea”) because the extraction efficiency can be increased and the deterioration with time due to self-digestion can be suppressed. A dry leaf refers to a leaf having a water content of 5% by weight or less. A method for producing dried leaves is disclosed in, for example, Japanese Patent No. 4340812. The term “powder” generally refers to a powder having a size that is commercially available as Tochu tea.

  Since the green leaves are fermented at 20 to 26 ° C. to lose the active ingredients, it is preferable to dry the green leaves in an environment of less than 20 ° C. The drying temperature is more preferably 10 ° C. or less, further preferably 3 ° C. or less, and still more preferably 0 ° C. or less. The humidity of the atmosphere during drying is preferably 60% or less, more preferably 20% or less, and even more preferably 15% or less. Or you may dry a cocoon leaf at the temperature exceeding 26 degreeC. The temperature in this case is preferably 50 ° C. or higher, more preferably 60 ° C. or higher, and still more preferably 70 ° C. or higher. The humidity of the atmosphere during drying is preferably 60% or less, more preferably 20% or less, and even more preferably 15% or less. The drying atmosphere may be in the presence of nitrogen or under reduced pressure.

  In addition to this, it is also possible to pulverize the cocoon leaves and make them smooth and freeze-dry them, or freeze the cocoon leaves and pulverize them and freeze-dry them. Smoothie is a slurry-like product obtained by pulverizing cocoon leaves. Tochu Nakaha has a strong vein covered with Guttavelka, and the drying time differs greatly between the leaf portion and the vein. Because of this Guttabelka, only a powder of 15 to 20 μm can be obtained even if an airflow type pulverizer is used. This size is larger than the particle size (10-20 μm) of matcha. However, freezing cocoon leaves leaves many holes in the veins, making it easier to cut the fibers. Therefore, a 6-10 μm powder having a smaller particle size can be obtained by freeze-drying the green leaves. Such a fine powder 杜 中葉 is useful in that the lignan compound can be efficiently extracted. In addition, the finely powdered rice cake is also useful as a food with good taste.

  Furthermore, in addition to the above lignan compounds, Tochu Nakaba has polyphenols such as flavonoids effective for anticancer activity, iridoids of geniposide sun and asperoside, vitamin A, vitamin B1, and vitamin B2 required for polyphenol absorption. Contains vitamin C, vitamin E, folic acid, and dietary fiber. As described above, when the cocoon leaves are dried, the disappearance of these components can be reduced.

(2) Process B
In this step, the extract is extracted with alcohol to obtain an aqueous phase and an alcohol phase. The alcohol used in this step is not limited as long as it is separated from the aqueous phase. That is, the alcohol in step B is different from the alcohol in step A. From the viewpoint of workability and the like, an alcohol having 4 to 10 carbon atoms is preferable, and butanol, pentanol, or hexanol is particularly preferable. These alcohols include linear and branched alcohols. The extraction may be performed a plurality of times using 20 to 50% by volume of alcohol with respect to the amount of the extract. The target compound is present in the aqueous phase obtained in this step.

(3) Process C
In this step, the aqueous phase obtained in the previous step is separated and purified by normal phase chromatography and then reverse phase chromatography. Normal phase chromatography is chromatography in which the polarity of the stationary phase is higher than the polarity of the mobile phase. Reverse phase chromatography is chromatography in which the polarity of the mobile phase is higher than the polarity of the stationary phase. These separation and purification can be carried out using a known column. A preferred embodiment will be described below.

  As the separation and purification by normal phase chromatography, the aqueous phase is separated by hydrophilic interaction chromatography (step C1). It is preferable to use a water / acetonitrile mixed solvent as a developing solvent. In this step, a known column such as a column packed with silica gel as a fixed carrier can be used. By examining the activity of each fraction by the method shown in the Examples described later, it is possible to identify which fraction contains the target compound. For example, when a column packed with silica gel is used as a fixed carrier, it is preferable to obtain a fraction solution in a water / acetonitrile mixed solvent having an acetonitrile concentration of 70 to 90% by volume.

  Next, as separation and purification by reverse phase chromatography, the fraction solution containing the target compound obtained in the previous step C1 is separated by reverse phase partition chromatography (step C2). It is preferable to use a methanol / water / acetic acid mixed solvent as a developing solvent. In this step, a known column such as a column packed with silica gel whose surface is modified with octadecylsilyl group (ODS) can be used as a fixed carrier. When the column is used, it is preferable to obtain a fraction solution in a methanol / water / acetic acid mixed solvent having a methanol concentration of 5 to 20% by volume and an acetic acid concentration of 0.05 to 0.2% by volume.

  In step C2, a step of separating the fractionated solution in a methanol / water / acetic acid mixed solvent again by the reverse phase partition chromatography using an acetonitrile / water / acetic acid mixed solvent as a developing solvent may be provided. By re-separation, the target compound can be isolated to a higher degree. In this case, it is preferable to obtain a fraction solution in a mixed solvent having an acetonitrile concentration of 5 to 20% by volume and an acetic acid concentration of 0.05 to 0.2% by volume.

  As separation and purification by reverse phase chromatography, the fraction solution containing the target compound obtained in the previous step C2 is separated by polar group inclusion type reverse phase partition chromatography (step C3). A mixed solvent of acetonitrile / water / acetic acid is preferably used as a developing solvent. In this step, a known column such as a column packed with polar group-containing silica gel in which octadecyl group is chemically bonded via a polar group can be used as a fixed carrier. When the column is used, it is preferable to obtain a fraction solution in an acetonitrile / water / acetic acid mixed solvent having an acetonitrile concentration and an acetic acid concentration of 5 to 20% by volume and 0.05 to 0.2% by volume.

The fractionated solution obtained in the above step contains the purified target compound, and the target compound can be isolated by removing the solvent from this solution. In this case, a compound (formula (1a)) in which R and R ³ are hydrogen atoms and m and n are 0 in formula (1) is obtained. A compound having R or the like other than a hydrogen atom can be obtained by modifying the compound of the formula (1a) by a known method. For example, a compound in which R is an acetyl group can be obtained by acetylating a compound of the formula (1a) with acetic anhydride.

3. Food Composition The compound of the present invention has an activity of inhibiting the growth of cancer stem cells. Therefore, the compound is useful as a food composition having anticancer activity.

  Examples of the food composition include tablets, powders, jellies, smoothies and the like. The food composition may further contain flavonoids such as flavonoids, polyphenols such as quercetin, vitamins necessary for absorption thereof, ginger, stevia, mulberry leaves, sesame and the like. The content of the compound in the food composition is preferably 0.05 to 10% by weight, more preferably 0.1 to 10% by weight.

Hereinafter, the present invention will be described in more detail with reference to examples. The analytical instruments used are as follows.
(1) NMR
¹ H-NMR (400 MHz), ¹³ C-NMR (100 MHz), ² D-NMR: Recorded with an AVANCE III FT-NMR spectrometer (Bruker BioSpin) with a 5 mm BBFO probe.
The chemical shift (δ) was based on the solvent signal. Coupling constants (H-7, H-7 ', H-8, H-8') are determined by spin simulation based on iNMR version 5.4.4 (nucleomatica, Molfetta, Italy; http://www.inmr.net) did.
(2) Specific Optical Rotation A P-2100 polar meter (manufactured by JASCO Corporation) equipped with a halogen lamp and a 589 nm filter was used.
(3) High resolution mass spectrometry
A JMS-BU25 (GCmate II) mass spectrometer (manufactured by JEOL Ltd.) was used.

Example 1 Production of Compound of Formula (1a) Step A
A dry powder of Tochu Naka (Tochu Tea, manufactured by Chinzanen Co., Ltd.) was prepared. 126 g of Tochu tea was extracted with 500 mL of 70% by volume methanol aqueous solution to obtain a first extract. Subsequently, Tochu tea after the extraction operation was extracted again with 500 mL of hot water (105 ° C.) to obtain a second extract. The first extract and the second extract were combined to obtain an extract. The extract was concentrated under reduced pressure.

Process B
The concentrate was extracted three times using 1/3 volume of 1-butanol with respect to the concentrate to obtain an aqueous phase and a 1-butanol phase. A part of the aqueous phase was taken out, added with an appropriate amount of Celite (Celite 545, manufactured by Junsei Chemical Co., Ltd.), and then concentrated by drying. The amount of the extracted water phase is equivalent to 18.5 g of Tochu tea (dry powder), and W × 18.5 / 126 when the amount of the total water phase is W (g).

Process C1
The concentrated aqueous phase was separated using hydrophilic interaction chromatography. As a column, DIOL MB100-75 / 200 (500 g, manufactured by Fuji Silysia Chemical Ltd.) equilibrated with a water / acetonitrile mixed solvent having an acetonitrile concentration of 90% by volume was used. Through the column, 2500 mL of a mixed solvent having an acetonitrile concentration of 90% by volume and 2500 mL of a mixed solvent having an acetonitrile concentration of 80% by volume were passed through to obtain 625 mL of an eluate. The same operation was repeated once more (twice in total), and each mixed solvent was made into Tochu tea (dried powder) to obtain an eluate equivalent to 37 g. The fractions of the solution were screened for activity to obtain sixth and seventh fractions containing active ingredients. This corresponds to the second and third fraction solutions of the mixed solvent having an acetonitrile concentration of 80% by volume.

Process C2
The sixth and seventh fractions were combined and subjected to a separation step using reverse phase partition chromatography. As a column, Inert Sustain C18 HPLC (φ14 × 150 mm, 5 μm, manufactured by GL Sciences Inc.) was used. A methanol / water / acetic acid mixed solvent was used as a developing solvent, and a linear gradient elution method from 0.1% by volume acetic acid aqueous solution to methanol was employed (3 mL / min for 20 minutes). The eluate was collected every minute. Since activity was observed in the fraction solution of 4 to 5 minutes, the fraction solution was separated again using the column. At this time, a mixed solvent (3 mL / min) of acetonitrile (10% by volume) / water / acetic acid (0.1% by volume) was used as a developing solvent. Absorption at 254 nm was monitored with a UV detector. Activity was observed in the fraction around 15.5 minutes.

Process C3
The fraction in which the activity was recognized was further purified by subjecting it to a separation step using polar group inclusion type reverse phase partition chromatography. As a column, Inertsil ODS-EP (φ6 × 250 mm, 5 μm, manufactured by GL Sciences Inc.) was used. A mixed solvent (1 mL / min) of acetonitrile (10% by volume) / water / acetic acid (0.1% by volume) was used as a developing solvent. The compound of the invention was found in the 13.3 minute fraction.

  By removing the solvent from the fraction, a purified compound of the present invention represented by the formula (1a) was obtained. The compound was colorless and amorphous.

The analysis results are as follows.
ESI-MS m / z (rel.int.): 191 (88), 243 (21), 353 (13), 4 (2.5), 707 ([MH] ⁻ , 100);
FAB-HRMS (negative) m / z ([MH] ⁻ ): calcd. For C 32 H 35 O 18, 707.1824; found, 707.1781
NMR: Table 1
[α] ²⁰ _D : -30.2 (c 0.136, MeOH)

Example 2 Acetylation of Compound of Formula (1a) 3 mg of the compound represented by formula (1a), 200 μL of pyridine, and 100 μL of acetic anhydride were mixed and reacted at room temperature for 2 nights. The reaction product was concentrated under reduced pressure and purified by liquid chromatography using Inertsil ODS-EP (φ6 × 250 mm, 5 μm, manufactured by GL Sciences Inc.). A linear gradient elution method (20 minutes) from 0.1 volume% acetic acid aqueous solution to acetonitrile was adopted, and then acetonitrile was passed through (1 mL / min). As a result, a single peak was observed at 20.0 minutes, and it was confirmed that this was a completely acetylated compound represented by the formula (1b).

The analysis results are as follows.
¹ H-NMR:

[Example 3] Production of compound of formula (1a) Example 1 was carried out in the same manner except that 50 g of fresh leaves of Tochu Naka were used instead of Tochu tea. As a result, it was confirmed that the compound of the formula (1a) could be produced. The inventors first found that the compound of the present invention was produced from Tochu tea (dry powder), but as shown in this example, it was confirmed that the compound of the present invention could also be produced from fresh leaves.

[Example 4] Anti-cancer properties (evaluation in 2D culture)
The anti-cancer properties of the compounds of the present invention are shown in two clones of iCSCL-10A cells, which are cancer stem cell models produced by Professor Akihide Liang, Yokohama City University, and MCF-7 and MDA-MB-231 cells, which are breast cancer cell lines. And evaluated as follows. Details of these cells can be found in WO 2012/165287, “Induction of cells with cancer stem cell properties from nontumorigenic human mammary epithelial cells by defined reprogramming factors.” Nishi M, Sakai Y, Akutsu H, Nagashima Y, Quinn G , Masui S, Kimura H, Perrem K, Umezawa A, Yamamoto N, Lee SW, Ryo A. Oncogene. 33 (5): 643-52, 2014, and “Induced cancer stem-like cells as a model for biological screening and discovery of agents targeting phenotypic traits of cancer stem cell ”. Nishi M, Akutsu H, Kudoh A, Kimura H, Yamamoto N, Umezawa A, Lee SW, Ryo A. Oncotarget 5 (18): 8665-80, 2014 ing.

1) The compound obtained in Example 1 was dissolved in PBS (phosphate buffered saline) to prepare solutions of 0.5 μM, 1.0 μM, 5.0 μM, 10 μM, 50 μM, and 100 μM.
2) A solution having a concentration of 4 × 10 ⁴ cells / mL was prepared for two clones of iCSCL-10A cells. Moreover, the solution of the density | concentration of 2 * 10 < ⁴ > cell / mL was each prepared about MCF-7 and MDA-MB-231 cell.
3) 100 μL each of the cell-containing solution was seeded in a 96-well plate. Cell concentration in the well was iCSCL-10A in ^{4 × 10 3 cell / well,} MCF-7 and in ^{MDA-MB-231 2 × 10} 3 cell / well.
4) After incubation at 37 ° C. for 24 hours, 10 μL of the solution containing the compound obtained in Example 1 prepared in 1) was added to each well.
5) Thereafter, the cells were incubated at 37 ° C. for 24 hours, and the degree of cell proliferation was evaluated using a microscope and a cell proliferation assay kit (Cell Counting kit-8, manufactured by Dojindo Laboratories).
6) As a control, the same test was performed using the same amount of PBS instead of the compound obtained in Example 1.
7) The results are shown in FIG. 2A (the control result is 1.0, and the ratio to this is plotted on the vertical axis).

[Comparative Example 1]
The result of having performed the same test as Example 4 using chlorogenic acid instead of the compound obtained in Example 1 is shown.

  The results are shown in FIG. FIG. 2A clearly shows that the compound of the present invention exhibits high growth inhibitory activity against cancer stem cells even at relatively low concentrations. It is also clear that the compounds of the present invention show growth inhibitory activity against breast cancer cells at relatively high concentrations. On the other hand, as shown in FIG. 2B, such activity was not observed with chlorogenic acid.

[Example 5] Anticancer properties (evaluation in 3D spheroid culture)
The anticancer properties of the compounds of the present invention were evaluated as follows using iCSCL-10A cells, which are cancer stem cell models.
1) The compound obtained in Example 1 was dissolved in PBS (phosphate buffered saline) to prepare solutions of 0.5 μM, 1.0 μM, 5.0 μM, 10 μM, 50 μM, and 100 μM.
2) In each well of a 96-well plate (Ultra-Low Attachment Plat, Corning), 100 μL of spheroid medium (DMEM / F12 (1: 1) (Lonza), insulin (sigma aldrich) 5 μg / mL Hydrocortisone (manufactured by sigma aldrich) 0.5 μM, EGF (manufactured by sigma aldrich) 20 ng / mL, B-27 (registered trademark, manufactured by Life Technology) 2%, p / s (penicillin / streptomycin, manufactured by Life Technology) ) 1%).
3) The cells were seeded in each well so as to obtain a concentration of 16000 cells / well.
4) After incubation at 37 ° C. for 4 days, 10 μL of the solution containing the compound obtained in Example 1 prepared in 1) was added to each well.
5) Thereafter, the cells were incubated at 37 ° C. for 72 hours, and the degree of cell proliferation was evaluated using a cell proliferation assay kit (CellTiter-Glo ^™ , manufactured by Promega Corporation).
6) As a control, the same test was performed using the same amount of phosphate buffered saline (PBS) instead of the compound obtained in Example 1.
7) The results are shown in FIG. 3A (the control result is 1.0, and the ratio to this is plotted on the vertical axis).

[Comparative Example 2]
The result of having performed the same test as Example 5 using chlorogenic acid instead of the compound of the present invention is shown.

[Reference Example 1]
杜 Nakasei leaves were frozen and the leaf veins were cut using a mixer to obtain a smoothie. This smoothie was pre-dried at −40 ° C. and dried at −30 ° C. for 48 hours to obtain a dry powder. The obtained powder had a particle size of 6 to 10 μm, and it was possible to obtain a Tochu powder with extremely fine particles and good solubility.

FIG. 3 shows the results of the anticancer property test, and FIG. 4 shows a photograph of the medium after 72 hours of incubation. FIG. 3A clearly shows that the compound of the present invention exhibits high growth inhibitory activity against cancer stem cells even in 3D spheroid culture. On the other hand, as shown in FIG. 3B, such activity was not observed with chlorogenic acid. 3D spheroid culture is thought to reproduce the original function of the tissue highly unlike single layer 2D culture. Therefore, it is clear that the compound of the present invention has an effect of inhibiting cancer stem cell self-renewal.

Claims (3)

The following general formula (1):

(In the formula, R is independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an acyl group having 2 to 6 carbon atoms,
R ¹ and R ² are substituents on the benzene ring, independently a halogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkylene group having 2 to 5 carbon atoms,
m and n represent the numbers of R ¹ and R ² , respectively, and are 0 to 3,
R ³ is independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms)
The food composition containing the compound represented by these. The food composition according to claim 1, wherein R and R ³ are hydrogen atoms, and m and n are 0. The food composition according to claim 1 or 2, further comprising ginger, stevia, mulberry leaves, or egoma.