METHOD FOR INCREASING FLAVONOID CONTENT IN PLANT THROUGH TREATMENT WITH LOW-MOLECULAR-WEIGHT SULFUR COMPOUND

Abstract

The present invention relates to a method for increasing the flavonoid content in a plant, comprising treating the plant with a sulfur compound; a method for producing a plant with increased flavonoid content; a plant with increased flavonoid content, produced by the production method; an antioxidant composition or food composition comprising the plant, an extract thereof or a fraction thereof; and a composition for increasing the flavonoid content in a plant, comprising a compound represented by Formula (1) or (2) as an active ingredient. The sulfur compounds S17 and 3-(2-S) of the present invention activate the flavonoid pathway, which is a repository of various functional secondary metabolites, and thus, may strongly trigger the accumulation of functional flavonoids when applied to crops, thereby efficiently improving the added value of crops.

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Claims

1. A method for increasing the flavonoid content in a plant, comprising treating the plant with a sulfur compound.

2. The method for increasing the flavonoid content in a plant according claim 1, wherein the sulfur compound is a compound represented by following Formula (1) or (2). ##STR00004##

3. The method for increasing the flavonoid content in a plant according claim 1, wherein the concentration of the sulfur compound is 10 M to 250 M.

4. The method for increasing the flavonoid content in a plant according claim 1, further comprising treating the plant with sucrose.

5. The method for increasing the flavonoid content in a plant according claim 1, wherein the flavonoid is anthocyanin, kaempferol, cyanidin, quercetin, or isorhamnetin.

6. The method for increasing the flavonoid content in a plant according claim 1, wherein the plant is one or more selected from Chinese cabbage, Arabidopsis thaliana, rice, wheat, barley, corn, soybeans, potatoes, red beans, oats, sorghum, radish, red peppers, strawberries, tomatoes, watermelons, cucumbers, cabbage, Korean melons, pumpkins, green onions, onions, and carrots.

7. A method for producing a plant with increased flavonoid content, comprising treating the plant with a sulfur compound.

8. The method according claim 7, wherein the sulfur compound is a compound represented by following Formula (1) or (2). ##STR00005##

9. The method according claim 7, wherein the concentration of the sulfur compound is 10 M to 250 M.

10. The method according claim 7, further comprising treating the plant with sucrose.

11. The method according claim 7, wherein the flavonoid is anthocyanin, kaempferol, cyanidin, quercetin, or isorhamnetin.

12. The method according to claim 7, wherein the plant is one or more selected from Chinese cabbage, Arabidopsis thaliana, rice, wheat, barley, corn, soybeans, potatoes, red beans, oats, sorghum, radish, red peppers, strawberries, tomatoes, watermelons, cucumbers, cabbage, Korean melons, pumpkins, green onions, onions, and carrots.

13. A plant with increased flavonoid content, produced by the method according to any one of claims 7 to 12.

14. The plant with increased flavonoid content according claim 13, wherein the flavonoid is anthocyanin, kaempferol, cyanidin, quercetin, or isorhamnetin.

15. The plant with increased flavonoid content according claim 13, wherein the plant is one or more selected from Chinese cabbage, Arabidopsis thaliana, rice, wheat, barley, corn, soybeans, potatoes, red beans, oats, sorghum, radish, red peppers, strawberries, tomatoes, watermelons, cucumbers, cabbage, Korean melons, pumpkins, green onions, onions, and carrots.

16. An antioxidant composition comprising the plant with increased flavonoid content according to claim 13, an extract thereof or a fraction thereof.

17. The antioxidant composition according claim 16, wherein the flavonoid is anthocyanin, kaempferol, cyanidin, quercetin, or isorhamnetin.

18. The antioxidant composition according to claim 16, wherein the plant is one or more selected from Chinese cabbage, Arabidopsis thaliana, rice, wheat, barley, corn, soybeans, potatoes, red beans, oats, sorghum, radish, red peppers, strawberries, tomatoes, watermelons, cucumbers, cabbage, Korean melons, pumpkins, green onions, onions, and carrots.

19. A food composition comprising the plant with increased flavonoid content according to claim 13, an extract thereof or a fraction thereof.

20. The food composition according claim 19, wherein the flavonoid is anthocyanin, kaempferol, cyanidin, quercetin, or isorhamnetin.

21. The food composition according to claim 19, wherein the plant is one or more selected from Chinese cabbage, Arabidopsis thaliana, rice, wheat, barley, corn, soybeans, potatoes, red beans, oats, sorghum, radish, red peppers, strawberries, tomatoes, watermelons, cucumbers, cabbage, Korean melons, pumpkins, green onions, onions, and carrots.

22. A composition for increasing the flavonoid content in a plant, comprising a compound represented by following Formula (1) or (2) as an active ingredient. ##STR00006##

23. The composition according claim 22, wherein the flavonoid is anthocyanin, kaempferol, cyanidin, quercetin, or isorhamnetin.

24. The composition according to claim 22, wherein the plant is one or more selected from Chinese cabbage, Arabidopsis thaliana, rice, wheat, barley, corn, soybeans, potatoes, red beans, oats, sorghum, radish, red peppers, strawberries, tomatoes, watermelons, cucumbers, cabbage, Korean melons, pumpkins, green onions, onions, and carrots.

25. Use of a compound represented by following Formula (1) or (2) for increasing the flavonoid content in a plant. ##STR00007##

26. Use of a compound represented by following Formula (1) or (2) for producing a plant with increased flavonoid content. Formula (1)

Description

DESCRIPTION OF DRAWINGS

[0052] FIG. 1 shows the results of confirming anthocyanin coloration of Chinese cabbage cultivars 5923 and Whimori treated with S17 or 3-(2-S).

[0053] FIG. 2 shows the analysis of flavonoid substances of Chinese cabbage cultivar Whimori (group treated with both 50 M S17 and 4% sucrose) through HPLC.

[0054] FIG. 3 shows the results of flavonoid production in Chinese cabbage cultivar 5923 according to the presence or absence of treatment with both the sulfur compound (S17 or 3-(2-S)) of the present invention and sucrose.

[0055] FIG. 3 shows the results of flavonoid production in Chinese cabbage cultivar Whimori according to the presence or absence of treatment with both the sulfur compound (S17 or 3-(2-S)) of the present invention and sucrose.

[0056] FIG. 5 shows the anthocyanin coloration results of Arabidopsis thaliana treated with both the sulfur compound (S17 or 3-(2-S)) of the present invention and sucrose.

[0057] FIG. 6 shows the anthocyanin coloration results of rice cultivar purple rice treated with S17 or 3-(2-S).

BEST MODE

[0058] Hereinafter, the configuration and effects of the present invention will be described in more detail through examples. These examples are only for illustrating the present invention, and the scope of the present invention is not limited thereto.

Example 1: Confirmation of Increase in Flavonoid Content in Chinese Cabbage Following Treatment with Sulfur Compound

1-1. Analysis of Coloring Effect

[0059] 3-(3-Thienyl) acrylic acid (hereinafter referred to as S17) and 3-(2-Thienyl) acrylic acid (hereinafter referred to as 3-(2-S)) dissolved in DMSO at a concentration of 50 M or 200 M, respectively, were prepared, and seeds of commercial Chinese cabbage cultivars 5923 and Hwimori were sterilized and then germinated on MS solid medium to prepare 4-day seedlings showing consistent growth. Afterwards, solid medium was prepared by adding 50 M or 200 M of S17 or 3-(2-S) to MS solid medium containing or not containing 4 parts by weight sucrose (4%) based on 100 parts by weight of the total medium, and then, day 4 seedlings were placed on the solid medium and cultured for 10 days, and the accumulation of anthocyanins was observed with the naked eye.

[0060] As a result, as shown in FIG. 1, in the case of the cultivar 5923, it was confirmed that when treated with S17 alone, coloration appeared on the back of the leaves in the 200 M treated group, and it was confirmed that in the group treated with both S17 and sucrose, coloration appeared on the back of the cotyledons and true leaves at 50 M and slightly increased coloration appeared at 200 M. Coloration was confirmed in the group treated with both 3-(2-S) at a concentration of 200 M and 4% sucrose. It was confirmed that the cultivar Whimori showed a similar coloration pattern to the cultivar 5923 and both S17 and 3-(2-S) caused red coloration in Chinese cabbage in a concentration-dependent manner, causing anthocyanin accumulation.

1-2. Evaluation of Flavonoid Increasing Effect

[0061] The leaves of the cultivars 5923 and Whimori prepared in Example 1-1 were collected and crushed, and then extracted with 50% methanol containing 2N HCl at 95 C. for 2 hours, and flavonoid substances present in the form of glycosides in the plants were aglyconized and analyzed by HPLC. After the substances were separated through HPLC using a C18 column, peaks were detected at 350 nm and 520 nm, and flavonoids and anthocyanin non-glycosides in the extract were identified by comparing the retention time and UV spectrum of flavonol non-glycoside standards such as kaempferol, quercetin, myricetin and isorhamnetin, and anthocyanin non-glycoside standards such as pelargonidin, cyanidin and delphinidin, respectively, and the content of the identified flavonoid and anthocyanin substances was estimated based on the concentration of the standards and the area of the peak. As a control group, the cultivar 5923 or Whimori that was not treated with sulfur compounds was used.

[0062] Analysis of flavonoid substances through HPLC is as shown in FIG. 2 (Chinese cabbage cultirvar Hwimori, group treated with both S17 (50 M)+4% sucrose).

[0063] As a result, as shown in FIG. 3, in the case of the cultivar 5923, it was confirmed that when treated with S17 or 3-(2-S) alone, kaempferol increased in a concentration-dependent manner, and when treated with 200 M of S17 or 3-(2-S), kaempferol increased up to 2.5 times compared to the control group not treated with the sulfur compound, and cyanidin was accumulated.

[0064] In the case of the cultivar 5923 group treated with both S17 and 4% sucrose, the kaempferol content increased up to 6.3 times compared to the control group in the 50 M S17 treated group, and the production of quercetin and isorhamnetin was confirmed. In the 200 M S17 treated group, cyanidin content remarkably increased compared to the control group. In addition, it was confirmed that the anthocyanin production ability triggered in the 50 M S17 treated group was remarkably enhanced in the 200 M treated group. These results suggest that the accumulation of different types of flavonols was induced when treated in combination with 4% sucrose.

[0065] In the case of the cultivar 5923 group treated with both 3-(2-S) and 4% sucrose, flavonol and cyanidin accumulation patterns similar to those observed when treated with S17 were confirmed.

[0066] In the case of the cultivar Whimori, as shown in FIG. 4, it was confirmed that when treated with S17 or 3-(2-S) alone, the kaempferol content remarkably increased compared to the control group, and when treated with both S17 and 4% sucrose, the kaempferol content remarkably increased in the 50 M and 200 M S17 treated group compared to the control group, and quercetin, isorhamnetin and cyanidin were produced. When treated with both 3-(2-S) and 4% sucrose, it was confirmed that the kaempferol content increased in a concentration-dependent manner, and quercetin, isorhamnetin and cyanidin were produced in the 200 M 3-(2-S) treated group.

[0067] Through these results, it was confirmed that when Chinese cabbage was treated with S17 or 3-(2-S), the activation of the flavonoid metabolic pathway may be promoted, leading to the production and accumulation of flavonols and anthocyanins, and this effect may be maximized through combined treatment with sucrose.

Example 2: Confirmation of Increase in Flavonoid Content in Arabidopsis thaliana Following Treatment with Sulfur Compound

[0068] To confirm whether anthocyanin coloring effect occurs when Arabidopsis thaliana, which is a cruciferous plant such as Chinese cabbage, is treated with S17 or 3-(2-S), Arabidopsis thaliana was treated with S17 or 3-(2-S) alone, and each was treated with 4% sucrose.

[0069] Specifically, Arabidopsis thaliana seeds were germinated on MS solid medium supplemented with 1% sucrose, and then day 6 seedlings were placed on MS medium supplemented with each of S17 (50 M or 200 M)+4% sucrose, or 3-(2-S) (50 M or 200 M)+4% sucrose and cultured for 5 days to observe anthocyanin coloration.

[0070] As a result, as shown in FIG. 5, it was confirmed that anthocyanin coloration did not appear in the non-treated control group (DMSO), but anthocyanin coloration occurred in all treated groups and anthocyanin was produced with stronger coloring in the S17 treated group compared to the 3-(2-S) treated group.

[0071] Through these results, it was confirmed that treatment with S17 or 3-(2-S) could induce anthocyanin accumulation through combined treatment with sucrose not only in Chinese cabbage but also in other dicotyledonous plants.

Example 3: Confirmation of Increase in Flavonoid Content in Rice Following Treatment with Sulfur Compound

[0072] To confirm whether anthocyanin coloring effects occur when not only dicotyledonous plants but also gramineous plants, which are monocotyledonous plants, are treated with S17 or 3-(2-S), seeds of the rice cultivar purple rice were sown on MS medium containing each of S17 (40 M) or 3-(2-S) (80 M) and cultured for 7 days to observe anthocyanin coloration.

[0073] As a result, as shown in FIG. 6, it was confirmed that coloration did not appear in the hypocotyls of the sulfur compound-untreated control group (DMSO), while anthocyanin was produced since anthocyanin coloration was strong in the hypocotyls of the S17 or 3-(2-S)-treated group. In this case, the two treated group showed similar effects at a lower concentration of S17 (40 M) compared to the concentration of 3-(2-S) (80 M), suggesting that the coloration-inducing effect (anthocyanin production effect) of S17 is comparatively superior to that of 3-(2-S) even in rice.

[0074] These results indicate that anthocyanins may be produced through treatment with S17 or 3-(2-S) even in gramineous plants, which are monocotyledonous plants.

[0075] From the above description, those of ordinary skill in the technical art to which the present invention pertains will understand that the present invention may be implemented in other specific forms without changing the technical spirit or essential characteristics thereof. In this regard, it should be understood that the examples described above are illustrative and not restrictive in all respects. It should be construed that all changes or modifications derived from the meaning and scope of the claims to be described later rather than the detailed description and their equivalent concepts are included in the scope of the present invention.