JP2006056796A - Production method of sesame lignan - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for efficiently obtaining high-purity lignans, especially sesamin, from sesame seeds or sesame oil. <P>SOLUTION: In the production method of sesame lignan, a mixture obtained by adding 0.5-10 pts.wt. nonpolar solvent represented by hexane to 1 pt.wt. sesame seeds is kept at 40-60°C for 0.5-3.0 hr and subsequently cooled to -5 to 40°C to crystallize sesame lignans, especially sesamin, extracted by the nonpolar solvent. Here, the sesame seeds can yield sesame oil with a sesame lignan content of ≥0.5 wt.%, preferably ≥1.0 wt.%, through a known method. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a method for producing lignans contained in sesame seeds, and more particularly to a method for obtaining highly pure lignans efficiently, easily and inexpensively.

Sesame seeds or sesame oil obtained by squeezing sesame seeds contains various sesame lignans such as sesamin, sesamorin, and sesaminol. These sesame lignans have been confirmed to have many physiologically active functions such as cholesterol-lowering action and carcinogenesis-inhibiting action, and are expected to be used in a wide range of applications such as health foods and pharmaceuticals.
Conventionally, when separating sesame lignans from sesame seeds and sesame oil, a method using a difference in vapor pressure due to a difference in molecular weight between triglyceride in which lignans are dissolved and lignans, and a difference in solubility such as polarity with respect to the solvent used are used. What to do was the subject.
For example, a method in which sesame oil is directly subjected to molecular distillation to obtain sesame lignan (Patent Document 1), a distillate obtained by steam distillation of sesame oil under reduced pressure is dissolved in a solvent, and then treated with alkali to precipitate sesamins.・ Separation method (Patent Document 2), sesame oil is extracted under supercritical conditions to obtain sesame lignan (Patent Documents 3 and 4), and lignans are dissolved in sesame oil using a polar solvent such as alcohol. There is known a method for concentrating them (Patent Documents 5 and 6).
However, these distillation methods require high temperatures and high vacuum conditions, so the equipment becomes heavy and expensive to install and operate, and other impurities are likely to be mixed, and the purity of sesame lignan is low. However, there is a fatal defect that once the operation for obtaining an oil and fat extract such as sesame oil is necessary, the operation becomes complicated, and the purity of sesame lignan is not so high as in the distillation method due to the incorporation of triglyceride.

Japanese Patent Laid-Open No. 10-120695 Japanese Patent Laid-Open No. 10-7676 JP 2000-290679 A JP 2000-159787 A Japanese Patent No. 3001589 Japanese Patent No. 3512196

  The present invention overcomes the above-mentioned problems in the production of lignans contained in sesame seeds and provides a method for obtaining high-purity lignans efficiently, easily and inexpensively.

As a result of intensive studies to achieve this object, the present inventors have extracted sesame seeds containing lignans at a predetermined temperature with hexane, which is a nonpolar solvent not found in patents, literatures, etc. It was found that sesame lignans can be preferentially crystallized by cooling to a temperature below the extraction temperature, and the present invention has been completed.
That is, in the present invention, a mixture obtained by adding 0.5 to 10 parts by weight of hexane to 1 part by weight of sesame seeds is held at 40 to 60 ° C. for 0.5 to 3.0 hours, and then the mixture is added. It is a method for producing sesame lignan, which is cooled to -5 to 40 ° C. and crystallized sesame lignans using a non-polar solvent typified by hexane instead of a known polar solvent such as alcohol and acetone.

The method of the present invention utilizes the difference in the melting temperature of lignan and other fat-soluble components with respect to hexane. That is, a normal fat-soluble component has high solubility in hexane, and crystallization of crystals does not occur even when the hexane mixture is cooled, so that only lignans can be selectively separated.
In the present invention, the hexane mixture is cooled to crystallize the crystals of sesame lignans, and then the crystal components can be separated by ordinary treatment such as filtration and filtering.

In the present invention, sesame seeds having a sesame lignan content of sesame oil obtained by a known method of 0.5% by weight or more, preferably 1.0% by weight or more can be used.
The seed is effective when the content of sesame lignan contained in sesame oil obtained by a known method is 0.5% by weight or more, but is preferably 1.0% by weight or more in order to crystallize more effectively.
0.5 to 10 parts by weight of hexane, which is permitted to be used as an extraction solvent for food use, in a pressing koji obtained through heat treatment and a pressing process, which are known oiling methods, is used for the seed. The mixture is subjected to extraction treatment at a temperature of 40 to 60 ° C. for 0.5 to 3.0 hours at a temperature of -5 ° C. to 40 ° C., preferably 10 ° C. to 30 ° C. High-purity sesame lignan crystals can be easily crystallized by cooling to ℃ and allowing to stand for 1 to 10 days.
The standing time is not limited to this, and a longer time is more preferable. Moreover, it is also possible to use a centrifuge etc. as another method. The form of the sesame seed at the time of the extraction operation is not limited to the pressed rice bran, and crushed seeds, crushed seeds, etc. can be used, and is not limited to these.

By the method of the present invention, high-purity lignans can be obtained efficiently, easily and inexpensively from sesame seeds.

  Although the Example of this invention is shown below, the meaning of this invention is not limited to this from the first.

Sesame seeds are pulverized in a coffee mill, and 52.57 g of hexane (special grade reagent) is added 3.5 times the weight of 15.02 g of the sesame seeds. Shake extraction was performed to obtain miscella.
In order to separate the extraction residue from the miscella, filtration paper filtration was performed to obtain a clear miscella having a miscella concentration of 12.25% by weight.
Here, the clarified miscella after filtering the filter paper is referred to as an extracted oil before crystallization operation (hereinafter referred to as an extracted oil before crystallization) after vacuum distillation using a rotary evaporator and vacuum drying.
After standing, the filter paper was filtered to separate the miscella and the crystallized product to obtain 0.02 g of crystallized product. 3.99 g of extracted oil (hereinafter referred to as “extracted oil after crystallization”) subjected to vacuum drying after vacuum distillation of the miscella from which the crystallized product had been separated was distilled with a rotary evaporator.
The lignan content and purity of the extracted oil before crystallization, the extracted oil after crystallization, and the recovered crystallized product were measured under the following conditions, which are high performance liquid chromatography methods.
Column; COSMOSIL 5C18-AR-II
Mobile phase; water: methyl alcohol = 3: 7 (volume ratio)
Flow rate: 0.8ml / min
Detector: UV Detector
Measurement wavelength: 290nm
Table 1 shows the sesamin content and the sesamorin content calculated by comparison with the peak area of the standard substance, and the lignan content, which is the total value thereof, and Table 2 shows the purity and composition of the crystallized product.

From the results in Table 1, it can be seen that the lignan content of the extracted oil before the crystallization operation and the extracted oil after the crystallization operation are significantly reduced. This means that crystallization occurred in Misera during standing, and lignans were separated and recovered.
The results in Table 2 indicate that the separated crystallized product is an extremely high-purity lignan crystal having a purity of 90% or more. Further, sesamin exceeds 90% in terms of composition, which means that sesamin can be selectively recovered from lignans.
From the above results, it can be seen that the method of the present invention is an effective production method capable of obtaining sesame lignan very efficiently, easily and inexpensively, and selectively obtaining sesamin.
In addition, the lignan content in the oil content of this sesame seed is 2.625% from the numerical value of the extracted oil before crystallization in Table 1, and satisfies the conditions of the sesame seed used in the present invention.

50 kg of sesame seeds were fed to a bench plant scale stirring heat treatment apparatus, and heated for 20 minutes until the temperature reached 106 ° C. while stirring using indirect steam and direct steam.
After the heat treatment, pressing was performed twice using a pressing machine which is MH-104 manufactured by Suehiro EPM. The operating conditions of the pressing machine at this time were 5 mm for clearance and 18 rpm for the worm rotation speed, and 14.85 Kg of compressed oil and 34.25 Kg of pressed rice cake were obtained by this treatment.
It is a press squeezed after using the extractor made in-house for the obtained press squeezed and adding 73.98Kg of hexane at 60 ° C. which is 2.16 times the weight to the squeeze and leaving it to stand for 1 hour. The extraction residue and miscella were separated. The miscella obtained at this time was 48.28 kg, and the oil concentration in the miscella was 12.20% by weight.
The obtained miscella was allowed to stand at room temperature of 20 ° C. to 25 ° C. for 4 days, and then the supernatant as a miscella and the crystallized product were separated. 7.90 Kg of extracted oil obtained by distilling the obtained supernatant miscella and 65.49 g of a crystallization product as sesame lignan can be obtained, and extraction oil without crystallization operation and extraction when crystallization operation is performed The lignan content of the oil and the purity of the crystallized product were analyzed in the same manner as in Example 1. Table 3 shows the results of various extracted oils, and Table 4 shows the purity and composition of the crystallized product.

From the results of Table 3, it can be seen that the lignans content of the extracted oil before the crystallization operation and the extracted oil after the crystallization operation are significantly reduced as in Example 1. This means that crystallization occurred in Misera during standing, and lignans were separated and recovered.
The result of Table 4 shows that the purity of the separated crystallized product is 94.65%, which is a lignan crystal having a higher purity than that of Example 1, and the composition is sesamin 94.46. % And sesamin can be selectively recovered.
From the above results, the present invention is effective to scale up and to obtain sesame lignan very efficiently, easily, inexpensively, and even selectively sesamin even under a publicly known oil extraction method. It can be seen that this is a simple manufacturing method.
The lignan content in the oil of sesame seed press used for crystallization of lignans was 2.788% based on the numerical value of the oil extracted before crystallization in Table 3, and the sesame seeds used in the present invention. The condition is met.
[Comparative Example 1]

  The polar solvent ethanol and acetone (reagent grades, respectively) shown in various patent documents relating to the production method of sesame lignan were treated in the same manner as in Example 1, and the nonpolar solvent hexane in the present invention was treated. Compared to the results when used. The results are shown in Table 5.

From the results shown in Table 5, when the hexane extraction method and the ethanol extraction method are compared, the hexane extraction method easily crystallizes in a miscella state, and is recovered by a known general method and obtains extremely high purity sesame lignan crystals. be able to. On the other hand, in the ethanol extraction method, the oil can be separated into two layers during standing by miscella and the upper layer, which is a sesame lignan concentrated layer, is distilled to obtain a high sesame lignan content oil.
However, in this method, the amount of extracted oil is small, and the lignan purity is 10% or less, so it is not possible to obtain a high purity product of sesame lignan as in the method of the present invention.
In the acetone extraction method, separation is possible at an extremely low temperature such as −80 ° C. shown in Patent Documents 5 and 6, but no crystallization is observed at the same comparative example temperature of 20 ° C.
Therefore, the sesame lignan production method of the present invention can obtain sesame lignans efficiently, easily and inexpensively from seed raw materials as compared with other methods.

Sesame content of sesame lignans is 1.931% by weight, sesamorin content is 0.788% by weight (sesame lignans content is measured in the same manner as in Example 1), using hexane, isooctane (special grade reagent) 50 g of 50% by weight of each extracted and prepared miscella was placed in a pressure bottle of 100 ml capacity, and the two systems were allowed to stand at 20 ° C. for 3 days in the same constant temperature water bath. After standing, the miscella was filtered with a filter paper to obtain a crystallized product, and the extract oil was obtained after performing the crystallization operation by evaporating hexane and isooctane from the miscella as a filtrate by distillation under reduced pressure. The lignan content of the extracted oil before the crystallization operation and the extracted oil after the crystallization operation were analyzed in the same manner as in Example 1. The analysis results are shown in Table 6.

From the results in Table 6, when comparing the lignan content of the extracted oil before the crystallization operation of hexane and isooctane and the extracted oil after the crystallization operation, both non-polar solvent systems are significantly reduced. I understand. The isooctane crystallized product was a crystallized product having a high purity and a high sesamin composition like the hexane crystallized product. From these results, it can be seen that the present invention using a nonpolar solvent is effective as a production method for obtaining lignan crystals with high purity.

Claims (1)

A nonpolar solvent typified by hexane with respect to 1 part by weight of sesame seeds having a sesame lignan content of 0.5% by weight or more, preferably 1.0% by weight or more, contained in sesame oil obtained by a known method The mixture obtained by adding 10 parts by weight is kept at 40 to 60 ° C. for 0.5 to 3.0 hours, and then the mixture is cooled to −5 to 40 ° C. to extract the sesame lignans extracted into a nonpolar solvent. A method for producing sesame lignan, characterized by crystallizing.