Method for increasing apo-9'-fucoxanthinone in brown algae

Abstract

To increase apo-9'-fucoxanthinone content in brown algae.SOLUTION: The method for increasing apo-9'-fucoxanthinone in brown algae comprises a step of freezing law brown algae and a step of sun drying after thawing.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a method for increasing apo-9'-fucoxanthinone in brown algae. [Background technology]

[0002] Apo-9'-fucoxanthinone is a component isolated from brown algae that is expected to have hair growth, anti-wrinkle, and anti-inflammatory effects, and there are reports that apo-9'-fucoxanthinone has been isolated as an active ingredient from raw or dried brown algae (Non-Patent Documents 1 and 2). However, there have been no reports on methods for increasing its content.

[0003] The most common method for producing brown algae is to dry the harvested algae in the sun, but there are also other methods, such as blanching and salting the algae, or storing the blanched and salted algae in a refrigerator, and then removing the salt as needed, cutting the algae, and mechanically drying them. However, there have been no reports of a method in which raw brown algae are frozen, thawed, and then dried.

[0004] In addition, it is known that apo-9'-fucoxanthinone can be produced by oxidizing fucoxanthin with ozone (Non-Patent Document 3), but in this process, an unknown compound is also produced at the same time. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Biol. Pharm. Bull. 39, 1273-1283 (2016). [Non-Patent Document 2] DARU Journal of Pharmaceutical Sciences 2013, 21:62. [Non-Patent Document 3] Mar. Drugs 2018, 16, 275. Summary of the Invention [Problem to be solved by the invention]

[0006] The present inventors divided raw wakame seaweed into two pieces at the production site immediately after harvesting, freeze-dried one piece, and dried the other piece in the sun. Apo-9'-fucoxanthinone was not present in the freeze-dried product, and apo-9'-fucoxanthinone was confirmed only in the sun-dried product. In order to investigate the sun-drying conditions in detail, the present inventors transported raw wakame seaweed from the production site to the present inventors by frozen mail, thawed it, divided it into two pieces, freeze-dried one piece, and dried the other piece in the sun, as described above. As a result, apo-9'-fucoxanthinone was confirmed in both pieces of wakame seaweed, which was an unexpected result. The major difference between the previous method and this method was that the seaweed was frozen and then thawed. Thus, wakame that was freeze-dried as it was and wakame that was thawed once and then freeze-dried were prepared, and it was confirmed that the apo-9'-fucoxanthinone content in the thawed wakame seaweed was greatly increased. Furthermore, by freezing, thawing and then drying in the sun, we succeeded in increasing the apo-9'-fucoxanthinone content more than in sun-dried wakame.

[0007] It has been confirmed that this phenomenon of increased apo-9'-fucoxanthinone content due to the freezing and thawing process is not unique to wakame, but also occurs in Eisenia bicolor, a type of brown algae.

[0008] It is already known that when fucoxanthin contained in brown algae is isolated and decomposed in solution with ozone, components such as apo-9'-fucoxanthinone can be obtained. However, when this method of reaction is used, it has become clear that in addition to producing apo-9'-fucoxanthinone, by-products that are not present in wakame and whose safety has not been confirmed are also produced. To solve this problem, the researchers discovered a method in which raw wakame is directly treated under an ozone stream and then dried in the sun. This method allowed them to increase the apo-9'-fucoxanthinone content without producing by-products. [Means for solving the problem]

[0009] The gist of the present invention is as follows. (1) A method for increasing apo-9'-fucoxanthinone in brown algae, comprising freezing and thawing raw brown algae and then drying them in the sun. (2) The method according to (1) above, in which the process of freezing and thawing raw brown algae is repeated twice and then dried in the sun. (3) The method according to (1) or (2) above, in which raw brown algae are frozen and thawed, then treated under an ozone stream, and then dried in the sun. (4) A method for increasing apo-9'-fucoxanthinone in brown algae, which comprises treating raw brown algae under an ozone gas stream and then drying them in the sun. Effect of the Invention

[0010] According to the present invention, it is possible to increase the apo-9'-fucoxanthinone content in brown algae. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 shows the changes in apo-9'-fucoxanthinone and fucoxanthin due to drying in the sun. [Diagram 2] FIG. 2 shows the apo-9'-fucoxanthinone content in wakame that was freeze-thawed, freeze-dried, or sun-dried. [Diagram 3] FIG. 3 shows the effect of drying in the sun on the apo-9'-fucoxanthinone content. [Figure 4] FIG. 4 shows a flow chart for investigating the effect of the number of freeze-thaw cycles on the apo-9'-fucoxanthinone content. [Diagram 5] Figure 5 shows the results of a study on the number of freeze-thaw cycles for wakame (refrigerated product). [Figure 6] Figure 6 shows the results of a study on the effect of blanching wakame (refrigerated product). [Figure 7] FIG. 7 shows the results of ozone treatment of fucoxanthin (single item). [Figure 8] FIG. 8 shows the production of apo-9'-fucoxanthinone by ozone treatment of wakame seaweed. [Figure 9]FIG. 9 shows the effect of ozone treatment after freezing and thawing on the apo-9'-fucoxanthinone content. [Figure 10] Figure 10 shows the results of a verification of the effects of freezing and thawing on Eisenia bifida. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Examples of brown algae used in the present invention include wakame, Eisenia bicolor, Akamoku, Mitsuishikonbu, Gagome konbu, Nekoashikonbu, Hijiki, Matsumo, Mozuku, Mekabu (Wakame), Tamahahakimoku, Aowakame, Sargassum, Iroro, Ishige, Tamakushige, Kurohanmon, Iwaamiji, Tapestry, Sea fan, Monnashigusa, Jigamigusa, Nishishinokawa, Hanekurogashira, Usbaohgi, Kuromo, Myrtococcus monadelpha, Wisteria crataephala, Muchimo, Narrowbaakame, Chigaiso, Hirome, Kurome, Ecklonia cava, Hibamata, Siberian bladderwort, Sugimoku, Fukurohijiki, Oobamoku, and Isomoku.

[0013] The brown algae used in the present invention must be fresh. For example, when commercially available dried wakame seaweed is rehydrated and then frozen and thawed, apo-9'-fucoxanthinone is dissolved in the water during the rehydration, resulting in a decrease in the apo-9'-fucoxanthinone content in the wakame seaweed.

[0014] Heating brown algae before freezing and thawing reduces the effect of increasing the apo-9'-fucoxanthinone content, so it is preferable to keep the raw brown algae used in the present invention at 10°C or below without heating, and it is even more preferable to keep it at 0 to 5°C.

[0015] The freezing may be carried out at any temperature at which brown algae freeze, and for example, treatment is preferably carried out at -10°C or lower, and more preferably at -15 to -30°C.

[0016] Thawing may be performed by leaving the mixture at room temperature or by treating it with seawater or tap water, and the treatment temperature is preferably 30° C. or lower, and more preferably 5 to 25° C. From the viewpoint of the apo-9'-fucoxanthinone content, the mixture is preferably thawed twice. Thawing more than twice does not significantly increase the apo-9'-fucoxanthinone content.

[0017] There are no particular limitations on the sun drying, but in rainy weather, it is usually carried out for 2 days (nighttime) while bringing it inside. The temperature during drying is preferably 10 to 30°C, and more preferably 15 to 25°C.

[0018] Heating brown algae by boiling or the like after freezing and thawing and before drying in the sun enhances the effect of increasing the apo-9'-fucoxanthinone content in the brown algae.

[0019] Ozone treatment after freezing and thawing and before drying in the sun can increase the apo-9'-fucoxanthinone content without producing by-products.

[0020] When raw brown algae are treated under an ozone stream without freezing and thawing, and then dried in the sun, the apo-9'-fucoxanthinone content can be increased without producing by-products.

[0021] The ozone treatment is preferably carried out using an ozone generator that releases ozone into the air, and more preferably has an ozone generating capacity of 5000 mg / h or more. The ozone treatment is preferably carried out in a closed space, and in some cases, may be carried out in a plastic bag with an exhaust port. EXAMPLES

[0022] The present invention will be described in more detail below with reference to examples, but the scope of the present invention is not limited to the following examples.

[0023] In the following Examples, the contents of apo-9'-fucoxanthinone and fucoxanthin in brown algae were measured as follows.

[0024] (Method for measuring the content of apo-9'-fucoxanthinone and fucoxanthin in brown algae) Method 1 (normal analysis): 1.00 g of brown algae powder that had been crushed in a mill and stored in a vacuum desiccator was accurately weighed into a 50 mL centrifuge tube, and 10 mL of 80% methanol solution was accurately added. The mixture was left to stand at room temperature for 7 days for extraction, and the supernatant obtained after centrifugation at 3000 rpm for 10 minutes was analyzed by high performance liquid chromatography (HPLC).

[0025] Method 2 (simple analysis): 1.00 g of brown algae powder that had been crushed in a mill and stored in a vacuum desiccator was accurately weighed into a 50 mL centrifuge tube, and 10 mL of 60% methanol solution was accurately added. The mixture was extracted by shaking at 150 rpm for 5 hours in a 50°C water bath, and the supernatant obtained by centrifugation at 3000 rpm for 10 minutes was analyzed by HPLC.

[0026] HPLC analysis of both components was carried out under the following conditions. (Apo-9' fucoxanthinone) Analytical column: YMC-Triart C18 (S-3μm, 12nm, 150x3.0mmI.D.) Mobile phase: 32% acetonitrile Column temperature: 40°C Flow rate; 0.3mL / min Sample volume: 10 μL Measurement wavelength: UV230nm Retention time; 19.7 minutes (Fucoxanthin) Analytical column: YMC-Triart C18 (S-3μm, 12nm, 150x3.0mmI.D.) Mobile phase: 87% acetonitrile Column temperature: 40°C Flow rate; 0.3mL / min Sample volume: 10 μL Measurement wavelength: UV440nm Holding time; 9.7min

[0027] Example 1 Immediately after harvesting, three raw wakame stalks were cut lengthwise along the stem at the production site, one half was freeze-dried (a, b, c), and the other half was sun-dried (a', b', c'). When each dried wakame obtained was analyzed under the analytical conditions of method 1, apo-9'-fucoxanthinone was not present in the freeze-dried wakame that was frozen immediately after harvesting and then freeze-dried, and apo-9'-fucoxanthinone was only detected in the sun-dried wakame. Therefore, it was presumed that apo-9'-fucoxanthinone was produced by drying (sun drying). In addition, the relationship between the decrease in fucoxanthin and the increase in apo-9'-fucoxanthinone suggested that apo-9'-fucoxanthinone may be produced by the decomposition of fucoxanthin. The results are shown in Figure 1.

[0028] Therefore, in order to study the sun-drying conditions in detail, fresh wakame was procured from the production area by frozen delivery, and three wakame stalks were thawed using tap water and divided vertically along the stem, and one was freeze-dried (A, B, C) and the other was sun-dried (A', B', C') in the same manner as above. When each dried wakame obtained was analyzed using the analytical conditions of method 1, the unexpected result was that apo-9'-fucoxanthinone was confirmed in both wakame. The results are shown in Figure 2. The major difference between the previous method and this method was that the wakame was frozen and then thawed. Therefore, freshly harvested wakame was procured by refrigerated delivery and divided into four groups of three stalks each, the first group was sun-dried as it was, and the remaining three groups were frozen in a freezer at -18°C. The second group was freeze-dried as it was, and the third group was thawed with tap water, re-frozen, and freeze-dried. The remaining fourth group was also thawed with tap water, and then sun-dried. The resulting dried wakame was analyzed under the analytical conditions of Method 1. As a result, it was confirmed that the apo-9'-fucoxanthinone content of the frozen and thawed wakame increased significantly. Furthermore, by drying in the sun after freezing and thawing, it was possible to successfully increase the apo-9'-fucoxanthinone content to a greater extent than that of regular sun-dried wakame. The results are shown in Figure 3.

[0029] Example 2 Using raw wakame delivered by refrigerated delivery immediately after harvest, we investigated the effect of the number of freeze-thaw cycles on the apo-9'-fucoxanthinone content. Specifically, 15 raw wakame stalks were divided into 5 bags of 3 stalks each, and following the flow shown in Figure 4, 3 raw wakame stalks were dried in the sun as is (no thawing), while 12 raw wakame stalks were divided into 4 bags of 3 stalks each and frozen in a freezer for the study.

[0030] When the effects of varying the number of freeze-thaw cycles were examined using refrigerated raw wakame, it was found that two freeze-thaw cycles was appropriate. Freezing and thawing more than two times did not result in a significant increase in the apo-9'-fucoxanthinone content. The apo-9'-fucoxanthinone content in various types of sun-dried wakame was confirmed using the analytical conditions of Method 2. The results are shown in Figure 5.

[0031] Example 3 Using three pieces of refrigerated raw wakame, an experiment was conducted according to Table 1 below to examine the effect of blanching. Sun drying was carried out for two days (taken in at night) excluding rainy days. In the blanching process, the raw wakame was immersed in 80°C hot water for one minute and then immediately cooled with tap water. In the freezing and thawing process, the raw wakame was frozen in a -18°C freezer and thawed with tap water.

[0032] [Table 1]

[0033] The apo-9'-fucoxanthinone content in the various sun-dried wakame seaweed samples was confirmed using the analytical conditions of Method 2. As a result, it was confirmed that parboiling, performed after freezing and thawing and before sun-drying (Experiment 4), was more effective in increasing the apo-9'-fucoxanthinone content. The results are shown in Figure 6.

[0034] (Reference example 1) Fucoxanthin was exposed to sunlight and treated with ozone. Fucoxanthin (0.1 mg / mL) dissolved in ethanol was placed in a 20 mL sample bottle and exposed to ozone in a closed space using an ozone deodorizer (5000 mg / h). The color of the fucoxanthin solution became transparent within 10 minutes. HPLC analysis of this transparent ozone-treated solution confirmed the production of apo-9'-fucoxanthinone along with a peak of an unidentified by-product not present in wakame. The results are shown in the bottom of Figure 7. Solid fucoxanthin powder was also treated with ozone at the same time, but no visual change occurred. On the other hand, when the same concentration of fucoxanthin was filled into a quartz cell (without air) and exposed to sunlight outdoors during the day, approximately 40% of fucoxanthin disappeared, but only a small amount of apo-9'-fucoxanthinone was produced. Therefore, fucoxanthin is also decomposed into compounds other than apo-9'-fucoxanthinone when exposed to sunlight.

[0035] Example 4 We performed ozone treatment on raw wakame seaweed. The peak harvest season for wakame seaweed is only a few weeks in March, so this experiment was performed using raw wakame seaweed that had been thawed once and frozen and then thawed again, i.e., twice-frozen and thawed. The thawed wakame seaweed was hung in a closed space and exposed to ozone for two hours using an ozone deodorizer (5000 mg / h), causing the seaweed to change from brown to green. The green-colored wakame seaweed was then dried in the sun for two days. Each dried wakame seaweed obtained by this procedure was powdered and the apo-9'-fucoxanthinone content was confirmed using the analytical conditions of Method 1. As a result, the unidentified by-products that appeared when a single fucoxanthin solution was treated with ozone did not appear at all when raw wakame was treated with ozone. The results are shown in Figure 8.

[0036] Example 5 The effect of ozone treatment was examined using raw wakame that had been frozen and thawed twice. The raw wakame that had been thawed for the second time was divided into three equal parts, the first of which was frozen and freeze-dried as is, the second of which was sun-dried as is, and the third of which was hung in a closed space and exposed to ozone for two hours using an ozone deodorizer (5000 mg / h), and then sun-dried. The resulting dried wakame was powdered, and the apo-9'-fucoxanthinone content was confirmed using the analytical conditions of Method 1. As a result, the wakame that had been freeze-thawed twice, treated with ozone, and sun-dried showed a high apo-9'-fucoxanthinone content. The results are shown in Figure 9.

[0037] Example 6 As an example of brown algae other than wakame, we obtained raw Eisenia bicolor and examined the effects of freezing and thawing. Specifically, Eisenia bicolor was transported by refrigerated delivery immediately after harvest, divided into three equal parts, the first part was dried in the sun for two days, and the remaining two pieces were frozen in a freezer at -18°C. After freezing, one piece was freeze-dried as is, and the other piece was thawed in tap water and dried in the sun for two days. Each piece of Eisenia bicolor was ground in a mill and the apo-9'-fucoxanthinone content was confirmed using the analytical conditions of Method 1. As a result, the same freezing and thawing effects were confirmed for Eisenia bicolor as for wakame. The results are shown in Figure 10. [Explanation of symbols]

[0038] A9'F Apo-9'-fucoxanthinone FXN Fucoxanthin

Claims

1. A method for increasing apo-9'-fucoxanthinone in brown algae, comprising freezing and thawing raw brown algae, and then drying them in the sun.

2. 2. The method according to claim 1, wherein the raw brown algae is subjected to two repeated steps of freezing and thawing, and then dried in the sun.

3. 3. The method according to claim 1 or 2, wherein raw brown algae are frozen and thawed, then treated under an ozone stream and then dried in the sun.

4. A method for increasing apo-9'-fucoxanthinone in brown algae, comprising treating raw brown algae under a stream of ozone and then drying the algae in the sun.

Images