JPH0782554A - Antioxidant - Google Patents

Abstract

PURPOSE:To obtain a highly safe antioxidant having a persistent antioxidant activity by separating and purifying an extract obtained by the solvent extrac tion of an alga which belongs to the genus Laurencia of the family Rodomela. CONSTITUTION:An alga which belongs to the genus Laurencia of the family Rodomela is washed with water, lyophilized and ground. The resultant product is extracted with a solvent selected from among ethyl acetate, chloroform, acetone, isopropanol, n-hexane, and toluene, and the extract is filtered to remove impurities. The filtrate is separated and purified by silica gel chromatography and gel filtration or thin-layer chromatography to obtain an antioxidant having as the active ingredient at least either a compound of the formula (wherein X is H or Br) or a compound derived by opening the three-memberd ring (2', 3', 6') of the above compound, introducing methylene into one of the positions 2' and 3', and introducing methyl into the other.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an antioxidant. More specifically, it can be used for oils and fats or foods containing the same, as well as products such as cosmetics and pharmaceuticals, and has safe and extremely excellent antioxidant activity, and this antioxidant activity is stable for a long time. It relates to an oxidant.

[0002]

2. Description of the Related Art The most important problem in the process of storage, preservation and processing of oils and fats or foods containing them, as well as cosmetics and pharmaceuticals, is the oxidation or peroxidation reaction of oils and fats components due to oxygen in the air. . Oxygen is essential for the life support of living organisms, but on the other hand, since it is a highly reactive molecule, it reacts with various components in these products and oxidizes or peroxidizes them to reduce the value of the product. Let In particular, unsaturated fatty acids such as linoleic acid and linolenic acid contained in fats and oils are known to be easily peroxidized by oxygen to generate peroxidized fatty acids and free radicals, and also to generate carcinogenic substances. [Food packaging, 17 volumes, 106
Page (1986)]. Oxidation of the product causes coloration, discoloration, denaturation, off-flavor, deterioration of nutritional value and effectiveness, and generation of toxic substances, which leads to deterioration of quality.

Various antioxidants have heretofore been used in order to suppress the oxidation of unsaturated fatty acids and prevent the deterioration of product quality. These antioxidants have the effect of acting on peroxy radicals generated during oxidation to stop the oxidation chain reaction, or acting on free radicals to stop the oxidation reaction. As the antioxidant, for example,
Synthetic antioxidants such as BHA (butylhydroxyanisole) and BHT (butylhydroxytoluene) are generally used. However, it is known that these synthetic antioxidants have a problem in safety in terms of carcinogenicity, etc., and the rejection reaction of consumers has become strong, and the amount of use thereof has decreased.

Thus, expectations are high for antioxidants derived from highly safe natural products. However, as a natural antioxidant, natural Vitamin E
Only (α-tocopherol), Vitamin C, gallic acid and its derivatives, caffeic acid and its derivatives, etc. are known, and all of these natural product antioxidants have low antioxidant activity and their activity is low. There are drawbacks such as not sustaining stably for a long time. Therefore, there is a strong demand for natural antioxidants having strong antioxidant activity and stable activity for a long time.

As an antioxidant from seaweed, which is abundant in the sea near Japan, an extract from brown algae has recently been proposed (JP-A-2-245087, JP-A-3-2).
94384 and Japanese Patent Laid-Open No. 4-239593).
These antioxidant effects are still unsatisfactory in terms of their antioxidant activity and durability. Therefore, in practice, BH
It is strongly desired to develop a substance having a strong antioxidant activity which is almost the same as that of A or BHT and the activity of which is stable and stable for a long time.

[0006]

DISCLOSURE OF THE INVENTION The present invention has a stronger antioxidant activity than conventional natural antioxidants, has an antioxidant activity comparable to that of BHA and BHT, and maintains its activity for a long time. , Fats and oils or foods containing them, and cosmetics,
It is an object of the present invention to provide a highly safe antioxidant derived from a natural product that can be used in products such as pharmaceuticals.

[0007]

Means for Solving the Problems As a solution to the above problems, the present inventors have found that the compounds represented by the following general formula (I) and ring-opening compounds thereof have strong antioxidant activity, The present invention has been completed.

The gist of the present invention is as follows. Formula (I):

[0009]

[Chemical 2]

A compound represented by the following formula (wherein X represents a hydrogen atom or a bromine atom) [hereinafter referred to as a ring-closing compound (I)], and a two-membered ring of 2 ', 3', 6'of which is ring-opened. Then
An antioxidant containing at least one compound selected from a compound in which methylene is substituted at either the 2'-position or the 3'-position and methyl at the other [hereinafter referred to as a ring-opening compound (I)] as an active ingredient [ Hereinafter, both the ring-closing compound (I) and the ring-opening compound (I) will be referred to as compound (I). ]. The antioxidant as described above, which comprises a solvent-extracted extract of seaweed containing at least one compound selected from the compound (I) as an active ingredient. The antioxidant as described above, wherein the seaweed is a seaweed belonging to the genus Sozo (Laurencia) of the red alga Fujimatsumo family. The antioxidant as described above, wherein the seaweed belonging to the genus Sourezo (Laurencia) of the red alga Fujimatsumo family is Mitsudezozo, Kurosozo, or papyrazoso. The extraction solvent used for solvent extraction is ethyl acetate, chloroform, acetone, isopropanol, n (normal)-
The antioxidant as described above, which is a solvent selected from hexane and toluene.

Specific examples of the compound (I) contained as an active ingredient in the antioxidant of the present invention include laurin terol, debromolaurin terol, isolaurin terol, debromoisolaurin terol, alolaurin terol, and de laurin terol. Bromo allolaurin terol may be mentioned. The respective structural formulas are as follows.

[0012]

[Chemical 3]

X = Br Laurin terol X = H Debromolaurin terol

[0014]

[Chemical 4]

X = Br Isolaurin terol X = H Debromoisolaurin terol

[0016]

[Chemical 5]

X = Br Arolaurin terol X = H Debromo Arolaurin terol

The compound (I) is usually a seaweed containing the compound, for example, the red alga Larvencia sp.
) It is obtained by separating and purifying a solvent-extracted extract of seaweed belonging to the genus, but it may be chemically synthesized.

The active ingredient of the antioxidant of the present invention may be a purified compound (I) or a solvent-extracted extract of a seaweed belonging to the genus Soure (Laurencia) of the red alga Fujimatsumotsu family.

In the present invention, the red alga Fujisuma family Sozo (La
Examples of the seaweed of the genus urencia) include, but are not limited to, Mitsudezozo, Kurosozo, papyrazoso, Oosozo, and Hanezozo. Among them, Mitsudezozo, Kurosozo, and papyrazoso are particularly preferable in view of availability and content of the above compounds.

[0021] Then, the red alga Fujisuma family Sozo (Laurenci
a) In order to extract each of the above compounds from the seaweed of the genus, they can be extracted using a suitable solvent according to a conventional method. Seaweed can be used in the form of dry powder or raw seaweed, and after heating / refluxing or stirring, leave it at room temperature for a certain period of time, and concentrate or dry the crude extract obtained by filtration or centrifugation under reduced pressure. By doing so, a solvent extract can be obtained.

As the extraction solvent, hydrophilic solvents such as methanol, ethanol, propanol, butanol and acetone, and lipophilic solvents such as chloroform, ethyl acetate, pentane, hexane, heptane, benzene, toluene and acetonitrile are preferable. Among these, particularly preferable extraction solvents include ethyl acetate, chloroform, acetone, isopropanol, n-hexane, toluene and the like.

Each of the above solvents may be used alone,
It is an experimental procedure to obtain a solvent extract as described above from a lipophilic solvent layer by performing extraction and separation in a two-liquid layer system with water such as ethyl acetate / water or n (normal) -hexane / water. It is convenient. Further, when a solvent such as methanol that extracts a large amount of the hydrophilic substance together with the active ingredient of the present invention is used, it is effective to adopt a method of extracting and separating again with ethyl acetate / water, for example. is there.

Isolation and purification of compound (I) from the solvent-extracted extract and identification are carried out by a conventional method. For example, the extract or its concentrate is separated and purified by silica gel column chromatography, followed by gel filtration or thin layer chromatography (TLC). This purified fraction is further fractionated by, for example, high performance liquid chromatography (HPLC), and each fraction is identified by a nuclear magnetic resonance (NMR) method, a mass spectrometry (MS) method and the like.

Regarding NMR, a superconducting Fourier transform (FT) NMR device of 200 MHz or higher was used, and hydrogen ( ¹
H) and carbon ( ¹³ C) NMR spectra,
It is effective for identification to take a shift correlation two-dimensional NMR spectrum or the like. Regarding MS, gas chromatography mass spectrometry (GC-MS) is effective for identification.

The compound (I) or the solvent-extracted extract thereof obtained as described above can be used again after being dissolved in a solvent such as ethanol which is less likely to adversely affect fats and oils and foods containing the same. Further, each of the active ingredients of the antioxidant of the present invention can be used alone as an antioxidant, or two or more compounds (I) can be used in combination. It can also be used in combination with other natural antioxidants. When two or more kinds are used in combination, the mixing ratio is not particularly limited, and the addition amount of the compound and the purity of the solvent-extracted extract can be appropriately set according to the purpose of use and the like. It can also be used as an emulsion according to a conventional method.

The antioxidant activity is measured by a conventional method such as the thiobarbital (TBA) method or the iron rodan method.
The measurement is preferably performed continuously over a long period of time.

[0028]

The compound (I), which is an active ingredient contained in the antioxidant of the present invention, has an antioxidant activity similar to that of BHT and BHA, and its antioxidant activity is continuously stable for at least 40 days. Be sustained.

The antioxidant of the present invention can be safely used in oils and fats or foods containing the same, as well as products such as cosmetics and pharmaceuticals. The amount of the antioxidant of the present invention used varies depending on the type of compound (I), the type of antioxidant, etc.,
For example, the compound (I) may be added in an amount of 0.005 to 0.1% in order to exert an antioxidant effect by being mixed with oils and fats such as linoleic acid.
The degree is mixed.

[0030]

EXAMPLES The present invention will be described more specifically by showing examples and test examples.

(Example 1) Preparation of solvent-extracted extract Sophorae (Laur)
The seaweed Mitsu de Sozo (Laurencia okamurai) of the genus encia) was washed with water, freeze-dried and pulverized. This frozen crushed product
100 ml of ethyl acetate was added to 24.287 g, and the mixture was well stirred for 3 hours for extraction. The extract was filtered to remove insolubles, the filtrates were collected, and the solvent was removed under reduced pressure. 0.810 g of a blackish brown solvent-extracted extract was obtained. A part of this extract was dissolved in ethanol to prepare a 0.1% ethanol solution.

Measurement of Antioxidant Activity The antioxidant activity was measured by the TBA method using linoleic acid as a substrate in an ethanol-water system. The antioxidant activity is measured by the TBA method by Matsushita et al. (Oil Chemistry, Vol. 24, 481-482).
Page, 1975), and malondialdehyde produced by oxidation was colored red by reaction with TBA, and colorimetric determination was performed.

That is, in a 50 ml Erlenmeyer flask with a ground stopper, 10 ml of a 2 × 10 ^-2 M linoleic acid solution containing ethanol (20 parts) -0.1 M phosphate buffer (80 parts) as a solvent and 0.1 M phosphoric acid were used. 20 ml of a reaction solution was prepared by mixing 8 ml of the buffer solution (pH 7.0) and 2 ml of a 0.1% solvent-extracted ethanol solution. The concentration of the solvent-extracted extract in this reaction solution is 0.01%. The reaction solution was kept at 40 ° C. in an incubator, and the antioxidant activity of the reaction solution was measured initially every day and then at small intervals for 40 days.

That is, 0.1 ml of the reaction solution was placed in a test tube with a screw.
Was weighed, 2 ml of 35% trichloroacetic acid solution and a 0.36% TBA solution containing 0.1% sodium sulfite (anhydrous) were added,
Heat in a boiling bath for 15 minutes. After cooling with running water, 1 ml glacial acetic acid and 2 ml chloroform were added, and after shaking at 2500 rpm.
Centrifuge for 10 minutes. The absorbance of the supernatant was measured at 532 nm. As a control, an ethanol solution to which no solvent extract was added was used, and α-tocopherol which is a natural antioxidant and BHA which is a synthetic antioxidant were measured at the same concentration as that of the extract and compared.

The test results are shown together in FIG. When the sample starts to oxidize, the absorbance increases and reaches the highest point,
Absorbance decreases with less sample to be oxidized. Therefore, the antioxidant activity of which the absorbance peak starts to be early is weak and unstable. From FIG. 1, it was confirmed that this solvent-extracted extract stably maintained the antioxidant activity for 40 days or more similarly to BHA, and had a much stronger and more stable effect than α-tocopherol. .

(Example 2) Preparation of solvent-extracted extract Seaweed Crosozo (Lauren) of the genus Sozo collected on the coast of Kochi Prefecture
cia intermedia) 20.2 g of the sun dried product was used to obtain 0.65 g of a solvent-extracted extract using 100 ml of n-hexane. A part of this extract was taken and treated in the same manner as in Example 1.
A 1% ethanol solution was prepared.

Measurement of Antioxidant Activity Using the above ethanol solution, the antioxidant activity was measured for 40 days in exactly the same manner as in Example 1. Control, α-
Tocopherol and BHA were also prepared in the same manner as in Example 1 and their antioxidant activity was measured for 40 days. As a result, a result similar to FIG. 1 of Example 1 was obtained.

The solvent-extracted extract in this example has the same strong antioxidant activity as the synthetic antioxidant BHA, and stably maintains the antioxidant activity for 40 days or more. It was also found to have a much stronger and stable effect. The absorbance at 532 nm obtained for the solvent-extracted extract of this example was 1
0.036, 0.036 at 0, 15, 21, 29, 34 and 39 days respectively
The values were 0.033, 0.035, 0.037 and 0.034.

(Example 3) Preparation of solvent-extracted extract Seaweed Papyalazozo (La of the genus Sozo) collected on the coast of Kagoshima Prefecture
urencia papillosa) lyophilized product (25.3 g), chloroform (150 ml) was used to obtain 0.895 g of a solvent-extracted extract.
Take a portion of this extract and dissolve it in a commercially available sucrose fatty acid ester (1 part) -0.1M phosphate buffer (99 parts) to give 0.1%.
An emulsion of was prepared.

Measurement of Antioxidant Activity Using linoleic acid as a substrate in the ethanol-water system, the antioxidant activity was measured by the iron iron rhodan method. That is, the same reaction solution as in Example 1 was prepared in a 50 ml Erlenmeyer flask with a ground stopper, kept at 40 ° C. in a thermostat, and the generated peroxide was measured with time. 4.7m of 75% ethanol solution in 0.1ml of reaction solution
l, 0.3 ml of 30% ammonium rhodanate, and 2 x 10 ^-2
Exactly 1 minute after the addition of 0.3 ml of 3.5 M ferrous chloride in hydrochloric acid, the absorbance at 500 nm was measured initially every day and then at small intervals over a period of 40 days. As a control, an emulsion containing no solvent-extracted extract was used, and α-tocopherol and BHT were each adjusted to the same concentration as that of the extract, and the antioxidant activity was measured.

The test results are shown in FIG. A figure of the same type as that of FIG. 1 showing the results of Example 1 was obtained except that the absolute value of the vertical axis was different. The absorbance increases as the sample begins to oxidize, reaching a peak and then decreasing as the sample to be oxidized decreases. Therefore, the antioxidant activity of the antioxidant is weak when the mountain begins to form early. From FIG. 2, it can be seen that the solvent-extracted extract has a stable antioxidant activity for 40 days or longer, similarly to BHT, and is much stronger and more stable than α-tocopherol. It was

Example 4 Separation / Purification of Extracted Extract In Example 1, the active ingredient was separated / purified using 0.79 g of the solvent-extracted extract extracted with ethyl acetate. That is, this extract was subjected to silica gel column chromatography (silica gel 60; column size, 30 mm × 300 mm; developing solvent, hexane: ethyl acetate = 8: 1), and then TLC.
(MERCK silica gel 60; 2 mm × 20 cm × 20 cm; developing solvent, hexane: ethyl acetate = 5: 1) for separation and purification.
This purified fraction was further subjected to HPLC (column, Asahipak HIK
ARISIL- C18 6mmID × 250mmL; Dissolvent, MeOH / H ₂
O 2 = 80/20; detector, UV-254nm; flow rate, 1.0 ml / min) to isolate 0.12 g of purified substance A.

Preparation of Purified Substance and Measurement of Antioxidant Activity Part of the purified substance A was dissolved in ethanol to prepare a 0.1% ethanol solution. Using this ethanol solution, the antioxidant activity was measured for 40 days in exactly the same manner as in Example 1. As a control, an ethanol solution containing no purified substance A was used, and α-tocopherol which is a natural antioxidant and BHT which is a synthetic antioxidant were each measured at the same concentration as that of the purified substance A and measured and compared.

The test results are shown in FIG. As a result, a result similar to that of FIG. 1 of Example 1 was obtained, and the solvent-extracted extract in this Example retained the same strong antioxidant activity as the synthetic antioxidant BHT, and was much stronger than α-tocopherol. It was confirmed that it has a stable effect.

Analysis of Structure of Purified Substance A The purified substance A was identified by making full use of NMR at 300 MHz, GC-MS and the like. ^{The 1} H-NMR spectrum is shown in FIG. 4, the ¹³ C-NMR spectrum is shown in FIG. 5, and the GC-MS spectrum is shown in FIG. 6. The main signals are shown in Table 1.

[0046]

[Table 1]

From the results of GC-MS in Table 1, purified substance A
Can be confirmed to be a substance with a molecular weight of 295, 281and279
The presence of Br can be confirmed as the reduction from (M ⁺ -CH ₃ ) to 200 indicates the elimination of Br (bromine). Also, ¹
From H-NMR, a signal derived from the three-membered ring at δ = 0.56 ppm, a signal derived from the two aromatic ring protons at δ = 6.61 and 7.60 ppm, and a signal derived from the methyl proton of the aromatic ring at δ = 2.29 ppm were confirmed. ¹³ C-NMR data and literature [T. Irie, M. Suzuki, E. Kurosawa, and T. Masamu.
ne (Tetrahedron, 26, 3271--3277 1970
Year)], etc., and it turns out that it is laurinterol.

Example 5 Separation / Purification of Extract Extract In the same manner as in Example 4, the solvent-extract extracted with ethyl acetate in Example 1 was separated / purified to obtain HP.
About 0.02 g of the purified substance B, which is an antioxidant component, was isolated in the fraction that flowed out earlier than the purified substance A of Example 4 during the LC.

Preparation of Purified Substance and Measurement of Antioxidant Activity Part of the above purified substance B was dissolved in ethanol to give 0.1%.
To prepare an ethanol solution. Using this ethanol solution, the antioxidant activity was measured for 40 days in exactly the same manner as in Example 1. As a control, an ethanol solution containing no purified substance B was used, and α-tocopherol, a natural antioxidant, and BHA, a synthetic antioxidant, were used as a purified substance B.
The same concentration was measured and compared.

The test results are shown in FIG. Figure with control, alpha-tocopherol, and BHA results
A plot similar to that of FIG. 3 was obtained. Therefore, the solvent-extracted extract in this example has the same strong antioxidant activity as the synthetic antioxidant BHA, and
It was confirmed that the antioxidant activity was stably maintained for 40 days or longer, and that it had a stronger and more stable effect than α-tocopherol.

The purified substance B separated and purified by the analysis of the structure of the purified substance B was treated with 300 M in the same manner as in Example 4.
Identification was performed by NMR of Hz, GC-MS and the like. ¹
The H-NMR spectrum is shown in FIG. 8 and the GC-MS spectrum is shown in FIG. The main signals are shown in Table 2.

[0052]

[Table 2]

From the result of ¹ H-NMR in Table 2, δ = 6.54,
Signals derived from protons of three aromatic rings were confirmed at 6.68 and 7.38 ppm, and GC-MS showed that the substance had a molecular weight of 216. Therefore, purified substance B was purified substance A to Br.
It can be seen that it is debromolaurin terol in which (bromine) is eliminated.

Example 6 Separation / Purification of Extract Extract and Measurement of Antioxidant Activity 0.59 g of the solvent-extract extracted with n-hexane in Example 2 was treated in the same manner as in Example 4. As a result, 0.01 g of purified substance C was obtained. A part of the purified substance C was dissolved in ethanol to prepare a 0.1% ethanol solution, and the antioxidant activity was measured for 40 days in exactly the same manner as in Example 1.

As a result, a result similar to that of FIG. 7 was obtained.
Therefore, the purified substance C in this example is the synthetic antioxidant B.
It has the same strong antioxidant activity as HA, and stably maintains the antioxidant activity for 40 days or more.
It was found to have a much stronger and more stable effect than tocopherol. The purified substance C of this example
The absorbance at 532 nm obtained for was 10, 15, 21, 29,
0.028, 0.027, 0.035, 0.0 at 34 and 39 days respectively
It was 34, 0.037 and 0.038.

The purified substance C separated and purified in the elucidation of the structure of the purified substance C was treated with 300 M in the same manner as in Example 4.
As a result of identification by Hz NMR, GC-MS, etc., from the result of GC-MS, as with laurinterol,
It was confirmed that the substance had a molecular weight of 295, and ¹ H-NMR
In the result, the signal derived from the three-membered ring around δ = 0.5 ppm disappeared, and therefore it was found that the three-membered ring of laurinterol was an isolaurinterol in which the ring was opened.

Example 7 Separation / Purification of Extract Extract and Measurement of Antioxidant Activity 0.83 g of the solvent-extracted extract extracted with chloroform in Example 3 was separated / purified in Example 4 and Example 5. In the same manner as in (1), 0.01 g of purified substance D was obtained. A part of the purified substance D was dissolved in ethanol to prepare a 0.1% ethanol solution, and the antioxidant activity was measured for 40 days in exactly the same manner as in Example 1.

As a result, results similar to those shown in FIG. 9 were obtained.
Therefore, the purified substance D in this example is the synthetic antioxidant B.
It has the same strong antioxidant activity as HA, and stably maintains the antioxidant activity for 40 days or more.
It was found to have a much stronger and more stable effect than tocopherol. The purified substance D of this example
The absorbance at 532 nm obtained for was 10, 15, 21, 29,
0.035, 0.038, 0.035, 0.0 at 34 and 39 days respectively
It was 36, 0.038 and 0.035.

The purified substance D separated and purified in the elucidation of the structure of the purified substance D was treated with 300 M in the same manner as in Example 4.
As a result of identification by NMR of Hz, GC-MS and the like, it was confirmed from GC-MS that it was a substance having a molecular weight of 216, like debromolaurinterol, and ¹ H-N
The MR results showed that the signal derived from the three-membered ring at δ = 0.5 ppm disappeared, and therefore it was found that the three-membered ring of debromolaurinterol was ring-opened isodebromolaurinterol.

[0060]

According to the present invention, not only is it overwhelmingly superior to conventional natural antioxidants, but it is also a synthetic product, BH.
It is possible to easily provide a natural antioxidant having an antioxidant activity as strong as that of T or BHA and capable of stably maintaining the antioxidant activity for a long time. In addition, the antioxidant of the present invention, oils and fats or foods containing the same, further cosmetics,
It can be safely used for pharmaceutical products.

[Brief description of drawings]

FIG. 1 is a diagram showing the results of measuring the time course of antioxidant activity of ethyl acetate extract of Mitsudezozo, α-tocopherol and BHA by TBA method.

FIG. 2 is a diagram showing the results of time-dependent changes in antioxidant activity of papillazozo's chloroform-extracted extract, α-tocopherol, and BHT measured by the iron iron rodan method.

FIG. 3 is a diagram showing the results of measuring the antioxidant activity of purified substance A, α-tocopherol, and BHT, which were obtained by separating and purifying an ethyl acetate extract of Mitsudezozo, by the TBA method.

FIG. 4 ¹ H-NM of purified substance A (laurinterol)
It is an R spectrum.

FIG. 5: ¹³ C-NM of purified substance A (laurinterol)
It is an R spectrum.

FIG. 6: GC-MS of purified substance A (laurinterol)
It is a spectrum.

FIG. 7 is a graph showing the results of measuring the antioxidant activity of purified substance B, α-tocopherol, and BHA, which were obtained by separating and purifying the ethyl acetate extract of Mitsudezozo, by the TBA method.

FIG. 8: Purified substance B (debromolaurin terol) ¹
It is an H-NMR spectrum.

FIG. 9: G of purified substance B (debromolaurin terol)
It is a C-MS spectrum.

Front page continued (72) Inventor Akihiro Kawakubo 728 Mori, Iyo City, Ehime Prefecture Seaweed Research Institute Co., Ltd.

Claims (5)

[Claims] 1. Formula (I): (Wherein, X represents a hydrogen atom or a bromine atom), and the 2 ', 3', 6'three-membered ring is opened, and either the 2'position or the 3'position Methylene
On the other hand, an antioxidant containing as an active ingredient at least one compound selected from compounds substituted with methyl. 2. The antioxidant according to claim 1, which comprises a solvent-extracted extract of seaweed containing at least one selected from the compound represented by formula (I) and a ring-opening compound thereof as an active ingredient. 3. The seaweed is a red alga, Fujimatsumochi family Sozo (Laurenci
The antioxidant according to claim 2, which is a seaweed belonging to the genus a). 4. The antioxidant according to claim 3, wherein the seaweed belonging to the genus Soure (Laurencia) of the red alga Fujimatsumo family is Mitsudesoso, Kurosozo, or papyrazoso. 5. The extraction solvent used for solvent extraction is ethyl acetate, chloroform, acetone, isopropanol, n.
The antioxidant according to claim 2, which is a solvent selected from (normal) -hexane and toluene.