Cotton seed treatment method

Abstract

To provide a cottonseed treatment method which decreases gossypol contained in cottonseed.SOLUTION: A cotton seed treatment method can be provided which includes fermenting cotton seed in presence of a microorganism to decrease gossypol contained in the cotton seed. Bacillus natto may be used as the microorganism. The method may include heating the cotton seed at 121°C for 10 minutes in an autoclave, and then inoculating the Bacillus natto to the cotton seed and culturing the resultant at 40°C for 24 hours. The method may further include maturing the resultant at 4°C for 10 days. The method may further include drying the resultant at 80°C for 2 hours.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present disclosure relate to a method for treating cotton seeds.

Background Art

[0002] The genus Gossypium is a plant of the Malvaceae family and is one of the most important fiber crops. Cotton, which is the fiber part of cotton, is the fruit attached to cotton seeds. The cotton seeds remaining after harvesting cotton contain high-quality oil and protein, and also have a high content of vitamins and minerals, and are particularly excellent as nutrients. Considering the current global production of cotton, cotton seeds have the potential to be a food resource for about 500 million people.

[0003] On the other hand, cotton seeds contain gossypol, which is toxic. Gossypol is a terpenoid aldehyde unique to the genus Gossypium. Although the detailed mechanism of gossypol poisoning is not clearly understood, examples include apoptosis of spermatocytes, inhibition of intercellular communication at gap junctions, generation of reactive oxygen species, increase in intracellular calcium concentration, depolarization of the mitochondrial membrane, enhancement of proton permeability of the cell membrane, and inhibition of protein kinase C activity.

[0004] Therefore, as one of the measures to address the food crisis, the development of a method for treating cotton seeds to reduce and detoxify gossypol in cotton seeds is expected. Patent Document 1 discloses a method for decomposing gossypol by irradiating with far-infrared rays.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] One object of an embodiment of the present invention is to provide a method for treating cotton seeds that reduces gossypol contained in cotton seeds. **Means for Solving the Problems**

[0007] As a result of intensive studies to achieve the above object, the present inventors have found that by fermenting cotton seeds in the presence of microorganisms, gossypol contained in the cotton seeds can be reduced, and thus the present invention has been completed.

[0008] One embodiment of the present invention can provide a method for treating cotton seeds, which comprises fermenting cotton seeds in the presence of microorganisms to reduce gossypol contained in the cotton seeds.

[0009] Bacillus natto may be used as the microorganism. The cotton seeds may be heated in an autoclave at 121 °C for 10 minutes, inoculated with Bacillus natto, cultured at 40 °C for 24 hours, further aged at 4 °C for 10 days, and further dried at 80 °C for 2 hours. **Advantages of the Invention**

[0010] According to one embodiment of the present invention, there is provided a method for treating cotton seeds that reduces gossypol contained in cotton seeds. **Brief Description of the Drawings**

[0011]

Figure 1

Figure 2

Figure 3

[0012] Hereinafter, a method for processing cottonseed according to an embodiment of the present invention will be described in detail. However, the method for processing cottonseed according to an embodiment of the present invention is not to be construed as being limited to the description of the following embodiments and examples.

[0013] The method for processing cottonseed according to this embodiment ferments the cottonseed in the presence of microorganisms to reduce the gossypol contained in the cottonseed.

[0014] There are roughly four varieties of cottonseed according to this embodiment, which may be G. hirsutum L., Upland cotton, G. herbaceum Oliver, G. barbadense L. Sea island cotton, or G. nanking Meyen. The cottonseed according to this embodiment is preferably the seed of G. herbaceum Oliver. However, it is not limited thereto, and the cottonseed according to this embodiment may be the seed of the genus Gossypium of the Malvaceae family.

[0015] The cottonseed according to this embodiment may be sterilized before inoculating the microorganisms. The cottonseed according to this embodiment may be heated at 121°C for 10 minutes in an autoclave.

[0016] In this embodiment, the microorganisms used for fermentation are not particularly limited. As the microorganisms, for example, fungi, bacteria, or archaea may be used. As the bacteria used for fermentation, for example, gram-positive cocci may be used, such as Ruminococcus flavefaciens SIJPESTEIJN, 1948 or Ruminovoccus albus HUNGATE, 1957. As the bacteria used for fermentation, for example, gram-negative cocci may be used, such as Lampropedia hyalina SCHROETER, 1886. As the bacteria used for fermentation, for example, gram-positive bacilli may be used, such as Eubacterium cllulosolvens HOLDEMAN and MOORE, 1972. As the bacteria used for fermentation, for example, spore-forming bacilli may be used, such as Bacteroides succinogenes HUNGATE, 1950 or Butyrivibrio fibrisolvens BRYANT and SMALL. As the bacteria used for fermentation, for example, the intestinal symbiotic protist group of lower termites may be used, and species belonging to the phylum Parabasalia and the phylum Preaxostyla may be used. As the bacteria used for fermentation, for example, Bacillus subtilis may be used, or Bacillus subtilis var. natto may be used.

[0017] The cottonseed treatment method according to this embodiment ferments cottonseeds in the presence of microorganisms. The cottonseed treatment method may, for example, inoculate natto bacteria into sterilized cottonseeds and culture them at 40°C for 24 hours. The cultured cottonseeds may be further aged at 4°C for 10 days. The aged cottonseeds may be further dried at 80°C for 2 hours. However, the conditions for fermenting cottonseeds in the presence of microorganisms are not particularly limited. In the cottonseed treatment method according to this embodiment, by fermenting cottonseeds in the presence of microorganisms, the gossypol contained in the cottonseeds can be reduced.

[0018] Cottonseed contains up to about 36 mg of gossypol per gram. In this embodiment, the content of gossypol in cottonseed may be evaluated by measuring the content of gossypol in the cottonseed extract. As the material for the cottonseed extract, a pulverized product of cottonseed may be used. The pulverized product of cottonseed may be obtained by pulverizing cottonseed from which the outer cotton has been removed in a mortar. Since gossypol is stable in acetone, the cottonseed extract may be prepared by acetone-extracting the pulverized product of cottonseed. The cottonseed extract may be, for example, prepared by adding 50 ml of acetone to 1 g of the pulverized product of cottonseed and heating and extracting in a water bath at 100° C. for 20 minutes together with the sealed sample container. However, it is not limited thereto, and the cottonseed extract only needs to reflect the content of gossypol in cottonseed, and the extraction method is not particularly limited.

[0019] The content of gossypol in the cottonseed extract may be measured using HPLC (high performance liquid chromatography). The column may be, for example, an octadecyl group chemically bonded column used in reverse phase chromatography. Gossypol in the cottonseed extract may be detected by measuring the refractive index at a wavelength of 254 nm. The content of gossypol in the cottonseed extract may be calculated from a calibration curve prepared using a standard product of gossypol. However, it is not limited thereto, and as long as gossypol in the cottonseed extract can be separated and quantified, the method for measuring the content of gossypol is not particularly limited.

Example

[0020] An example of the method for treating cottonseed according to this embodiment is shown below, but this description is only an example and is not limited thereto.

[0021] <Example> 50 g of cottonseed was heat-sterilized at 121°C for 10 minutes using an autoclave (ST200, Yamato Scientific Co., Ltd.). Approximately 20 grains of natto were left from a commercially available natto pack (Okame Natto Super Fine Grains, Takano Foods Co., Ltd.), and the rest were removed. The heat-sterilized cottonseed was transferred into the natto pack while still hot and mixed well. The lid of the natto pack was covered from above, and the cottonseed was fermented at 40°C for 24 hours in a soft incubator (SLI-400, Tokyo Rika Kikai Co., Ltd.). The fermented cottonseed was aged for 10 days in a 5°C refrigerator (Biomedical Freezer MDF-U539-PJ, Panasonic) while still in the pack. The aged cottonseed was dried at 80°C for 2 hours using a high-temperature thermostat (Azalea, Isuzu Manufacturing Co., Ltd.) to obtain the cottonseed of the example.

[0022] <Comparative Example> Two to three grains of cottonseed were heat-sterilized at 121°C for 10 minutes using an autoclave (ST200, Yamato Scientific Co., Ltd.). The heat-sterilized cottonseed was dried at 80°C for 2 hours using a high-temperature thermostat (Azalea, Isuzu Manufacturing Co., Ltd.) to obtain the cottonseed of the comparative example.

[0023] <Preparation of Cottonseed Extract> Each cottonseed extract was prepared by acetone-extracting untreated, example, or comparative example cottonseed. The untreated, example, or comparative example cottonseed was each ground in a mortar to obtain a ground product of cottonseed. 0.1 g of each obtained ground product of cottonseed was placed in a vial (Mighty Vial, Maru EM), and 5 ml of acetone (Fuji Film Wako Pure Chemical) was added. The ground product of cottonseed was heated and extracted with acetone in a water bath at 100°C for 20 minutes. After water cooling, cottonseed extracts of untreated, example, and comparative example were obtained by passing through a 0.45-μm filter (Comonaise Filter W (aqueous system) 0.45 μm, nakalai tesque (Merck)).

[0024] <Measurement of Gosypol Content> HPLC was used to detect and quantify gossypol in the cottonseed extract of the untreated, example, or comparative example. For the detection and quantification of gossypol, a chart and a calibration curve using a gossypol standard were used. 3.0 mg of gossypol standard (G5874, FUJIFILM Wako Pure Chemical Industries, Ltd. (LKT)) was dissolved in 3 ml of acetone to prepare a 0.1% standard stock solution, and from this, 0.01%, 0.001%, 0.005%, and 0.0001% standard solutions were prepared. The calibration curve of gossypol was prepared using the average of the area values obtained by measuring each standard solution three times with an HPLC apparatus. Gossypol was detected at 3.8 minutes as a clean peak, well separated from the void peak around 2 minutes.

[0025] The detection conditions of HPLC are shown below. Column 5C18-MS-II (4.6ID×150mm) Mobile phase Methanol: 0.5% acetic acid aqueous solution = 9:1 Flow rate 1 ml / min Column temperature 40 °C Detection wavelength 254 nm

[0026] Figure 1 is an HPLC chart of the cottonseed extract according to an example of the present invention. Figure 2 is an HPLC chart of the cottonseed extract according to a comparative example of the present invention. Figure 3 is an HPLC chart of the untreated cottonseed extract. Table 1 shows the area values measured three times each with an HPLC apparatus, and the concentration and content of gossypol in the cottonseed extract.

[0027]

Table 1

[0028] As shown in Figure 1, in the cottonseed extract according to the example of the present invention, the peak of gossypol was not detected. On the other hand, as shown in Figure 2 and Table 1, in the cottonseed extract according to the comparative example of the present invention, an 8% gossypol content was detected compared to the untreated cottonseed extract.

[0029] As described above, in the cottonseed processing method according to the present embodiment, it was confirmed that gossypol contained in the cottonseed was removed to below the detection limit by fermenting the cottonseed in the presence of microorganisms.

Claims

**Claim 1** A method for treating cotton seeds, comprising fermenting the cotton seeds in the presence of microorganisms to reduce gossypol contained in the cotton seeds. **Claim 2** The method for treating cotton seeds according to claim 1, wherein Bacillus natto is used as the microorganism. **Claim 3** heating the cotton seeds in an autoclave at 121°C for 10 minutes, inoculating the cotton seeds with the Bacillus natto, and culturing at 40°C for 24 hours, the method for treating cotton seeds according to claim 2. **Claim 4** The method for treating cotton seeds according to claim 3, further comprising aging at 4°C for 10 days. **Claim 5** The method for treating cotton seeds according to claim 4, further comprising drying at 80°C for 2 hours.

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