JP4922550B2 - Process for producing banaba leaf extract with high corosolic acid content - Google Patents

Description

  In the present invention, banaba leaves are extracted with an aqueous solution containing 60% by volume to 100% by volume of ethanol, and the obtained extract is treated with 10 to 20% by mass of activated carbon with respect to 100 parts by mass of the dry mass of banaba leaves. An extract of banaba leaves high in corosolic acid, comprising the steps of separating the precipitate in the concentrate obtained by concentrating after increasing the corosolic acid content in the extract, and collecting the precipitate It relates to the manufacturing method.

  Banaba is a plant belonging to the family Lamiaceae that lives in tropical Asia. It has been used as a beverage since decocting this leaf, and banaba leaves have been used as a folk medicine because they have an effect on diabetes. In recent years, while eating habits have become richer, the incidence of lifestyle-related diseases such as obesity caused by too much biased nutrition and diabetes caused by obesity has not occurred, or there is no risk of onset. Since the so-called reserve group is increasing, it has been widely used as a raw material for so-called health foods that prevent obesity and diabetes by ingestion as food (for example, Patent Document 1).

  On the other hand, various studies have been conducted on banaba leaves, including ingredients. Among them, corosolic acid contained in banaba leaves has been found to be an activator of glucose movement in the body, affecting diabetes and its onset. It can lower blood sugar levels, and has attracted attention.

In this way, attempts have been made to extract functional components from banaba leaves and use them as raw materials. After extracting banaba leaves with hot water, a method of extracting functional components with styrene-divinylbenzene-based resin, or banaba leaves The method for increasing the corosolic acid content by examining the extraction conditions from the potato is disclosed (for example, Patent Documents 2 to 3).
JP 2001-103928 A JP-A-7-228539 JP 2000-169384 A

  However, it is difficult to obtain an extract obtained from banaba leaves, in particular, banaba leaves containing a high amount of corosolic acid, and a banaba leaf extract having a sufficient content cannot be obtained due to differences in raw materials or extraction conditions. There was a problem.

  Therefore, as a result of intensive studies on a method for obtaining an extract containing corosolic acid in a high amount from banaba leaves, the present inventors extracted banaba leaves with an aqueous solution containing ethanol, treated the extract with activated carbon, and By concentrating and collecting the precipitate, it was found that a banaba leaf extract having a high corosolic acid content can be obtained, and the present invention has been achieved.

  That is, the present invention is a step of extracting a banaba leaf with an aqueous solution containing 60% by volume to 100% by volume of ethanol to obtain a crude extract; the obtained crude extract is 10 parts per 100 parts by mass of the banaba leaf dry mass. A step of obtaining a treatment liquid having a corosolic acid content increased by treatment with ˜20% by mass of activated carbon; a step comprising separating the precipitate in the concentrated liquid obtained by concentration and collecting the precipitate; The present invention relates to a method for producing a banaba leaf extract containing 9% by mass or more of corosolic acid in terms of mass.

  According to the present invention, banaba leaves are extracted with an aqueous solution containing 60% by volume to 100% by volume of ethanol, and further treated with 10 to 20% by mass of activated carbon with respect to the dry mass of the raw material. A banaba leaf extract containing 9% by mass or more of corosolic acid can be obtained.

  The present invention will be described below. Note that the configuration described below does not limit the present invention and can be variously modified within the scope of the gist of the invention.

  The banaba leaves used as the raw material of the composition of the present invention are dried banaba (Lagerstroemia Speciosa, Linn. Or Pers.) Fresh leaves produced in the Philippines and the like. Since banaba leaves are susceptible to corrosion, it is preferable to dry them immediately after harvesting to obtain dried products. Fresh leaves may be dried either naturally or air-dried, but preferably forcedly dried by air-drying. Drying is performed so that the moisture content is 20% by mass or less, preferably 10% by mass or less, thereby preventing the corrosion of microorganisms and keeping the components in the banaba leaf stably.

  This dried product contains corosolic acid at a high content by performing the steps described below, (a) an extraction step with an aqueous ethanol solution, (b) a treatment step with activated carbon, and (c) a step of concentrating and recovering the precipitate. Banaba leaf extract can be obtained.

(A) Extraction step with aqueous ethanol solution First, the dried product is extracted with an aqueous ethanol solution to obtain a crude extract. For extraction, the dried product may be extracted as it is, but can be extracted efficiently by pulverizing or chopping. The dried product is pulverized by any machine or tool known to those skilled in the art, such as a cutter, a slicer, and a dicer. The particle size of the pulverized dry product is 20 mm or less, preferably 10 mm or less, and most preferably 1 mm or less. Extraction from the dried product with an aqueous alcohol solution is carried out so that the alcohol content is 60 to 100% by volume and added to the dried product. When the alcohol content is lower than 60% by volume, corosolic acid is hardly eluted from the dried product, and the corosolic acid content in the resulting crude extract is reduced. The amount of ethanol aqueous solution added for extraction or the temperature and method of extraction are not particularly limited, but it is prepared so that corosolic acid is eluted from the dried product into the solution. The amount of the aqueous ethanol solution added to the dried product is preferably 15 parts by mass or more with respect to 1 part by mass of the dried product. If it is less than 15 parts by mass, corosolic acid cannot be efficiently eluted from the dried product. The extraction temperature is below the temperature at which the aqueous ethanol solution boils, preferably 30 ° C. to 80 ° C., more preferably 50 ° C. to 80 ° C., and heating to reflux as necessary to prevent ethanol evaporation. Extraction can be performed. Moreover, the efficiency of extraction can be improved by performing stirring, and an extract containing a high amount of corosolic acid can be obtained. In addition, corosolic acid in the dried product can be extracted more efficiently by extracting multiple times. Moreover, you may remove the insoluble matter in an extract before the process by activated carbon described later.

(B) Treatment step with activated carbon Next, the obtained crude extract is brought into contact with activated carbon, and impurities are removed to obtain a treatment solution containing corosolic acid in a high amount. Normally, activated carbon is used for the purpose of decolorization or the like, but in the present invention, it is used for the purpose of increasing the content of corosolic acid in the solid content of the treatment liquid. Activated carbon preferably has a surface area of 200 to 800 m ² / g, more preferably 400 to 800 m ² / g, so that impurities in the extract can be adsorbed efficiently. Corosolic acid content of is increased. As long as the activated carbon has a surface area in this range, various commercially available products can be used. Specifically, Kayamax (Nippon Kayaku Co., Ltd.), activated carbon carborafin (Takeda Pharmaceutical Co., Ltd.) and the like can be mentioned. be able to. The amount of the activated carbon is 10 to 20% by mass per 100 parts by mass based on the dry mass of the banaba leaf used for extraction. The larger the amount of activated carbon, the more components in the crude extract are adsorbed, so corosolic acid is also adsorbed on the activated carbon, and the content is considered to decrease, but the amount usually used for decolorization, for example, from 5 to 10% by mass By using a large amount of activated carbon of 10 to 20% by mass, the yield of corosolic acid is good, and the content of corosolic acid in the solid content of the obtained treatment liquid can be increased. In addition, when less than 10 mass%, it is inadequate for the removal of a foreign material, and it will become difficult to raise content of corosolic acid.

  The contact method between the activated carbon and the extract can be performed by a method commonly used by those skilled in the art, such as a column method or a batch method. In addition, when processing with activated carbon, the corosolinic acid content in solid content contained in an extract is raised by processing at the temperature at the time of processing below the temperature which ethanol boils, Preferably it is 50 to 80 degreeC. In particular, heating to reflux is preferred.

  In order to perform the treatment using the column method, for example, first, activated carbon is packed in a column, the extract is passed through the column, and the eluted liquid is collected. Further, if necessary, an ethanol aqueous solution having the same concentration as that used for the extraction of 1 to 10 times the volume of the activated carbon is passed through, and this operation is preferably repeated and refluxed. Thereby, many impurities are adsorbed on the activated carbon and corosolic acid is sufficiently eluted from the column, so that the content of corosolic acid in the solid content of the obtained solution can be increased.

  In order to process using the batch method, the crude extract is added to activated carbon and brought into contact with stirring or refluxing for 30 minutes to 1 hour, and then the liquid layer is recovered by filtration or centrifugation. Furthermore, in order to increase the yield of corosolic acid, the residue can be washed with an aqueous ethanol solution having the same concentration as that used during extraction, and the washing solution can be recovered.

(C) Step of concentrating to recover the precipitate Next, the obtained treatment liquid is concentrated, the precipitate in the concentrated liquid obtained by concentration is separated, and the precipitate is recovered. The concentration method can be carried out by methods commonly used by those skilled in the art, such as heat drying and vacuum concentration. Preferably, the concentration of the components in the treatment liquid can be suppressed by concentration under reduced pressure. Concentration is performed until the ethanol concentration in the concentrated solution is 60% by volume or less, preferably 0 to 60% by volume. In the obtained concentrated solution, a precipitate in which corosolic acid is preferentially precipitated is generated due to a decrease in the ethanol content, so that the corosolic acid content contained in the precipitate is dramatically improved. Moreover, in order to fully produce a deposit, you may stand still at 1-50 degreeC for 1 hour-24 hours. The precipitate is separated from the concentrated solution by a method commonly used by those skilled in the art such as centrifugation and filtration, and the precipitate is recovered to obtain a banaba leaf extract containing a high amount of corosolic acid. In addition, the precipitate obtained in the concentration step, that is, the banaba leaf extract is washed with an ethanol aqueous solution of 60% by volume or less, preferably 30% by volume or less, to remove impurities, thereby removing the banaba leaf extract. Corosolic acid content can also be increased.

  The banaba leaf extract thus obtained can be used as it is in beverages and the like, but is preferably dried and powdered because it contains ethanol. The drying is performed by any method commonly used by those skilled in the art, such as hot air drying, high pressure steam drying, vacuum concentration drying, electromagnetic wave drying, freeze drying, spray drying, etc., but preferably vacuum concentration drying or freeze drying and spraying. It is dry. The drying is preferably performed until the water content in the solid content is 10% by mass or less, preferably 5% by mass or less. When spray drying is performed, an excipient such as dextrin, cyclodextrin, starch or maltose is added as necessary. Preferably, dextrin is used, and the ratio of extract to dextrin is preferably 1: 5 to 10: 1 in terms of dry substance amount.

  In addition, since the dried product of the extract obtained by drying often forms a lump, it is preferable to use a banaba leaf extract powder pulverized after drying. By powdering, not only can it be easily applied to various forms, but when it is ingested as a food, the absorption efficiency is increased, and an excellent blood glucose level increase suppressing effect can be easily obtained.

  The pulverization can employ the same method as the banaba leaf pulverization method described above.

  The powder obtained by pulverization is preferably 1000 μm or less, preferably 500 μm or less, and more preferably 20 to 200 μm, whereby high physiological activity such as an effect of suppressing an increase in blood glucose level can be obtained.

  The banaba leaf extract thus obtained contains a high content of corosolic acid and can contain 9 mass% or more, preferably 9 mass% to 50 mass% of corosolic acid in terms of the dry mass of the extract. Moreover, by treating with a predetermined amount of activated carbon, the unique flavor of banaba leaf is removed, and further, it is considered that undesirable components in banaba leaf are also removed, which is highly safe and versatile. The extract is easy to use as a food ingredient.

  The banaba leaf extract and this powder obtained by the present invention are used as they are, or excipients, extenders, binders, thickeners, emulsifiers, coloring agents, flavorings, food additives, seasonings, etc. Can be mixed with. For example, royal jelly, propolis, vitamins (A, B group, C, D, E, K, folic acid, pantothenic acid, biotin, and derivatives thereof) minerals (iron, magnesium, calcium, zinc, etc.), selenium, chitin Chitosan, lecithin, polyphenol (condensed tannins such as catechins, anthocyanins, proanthocyanidins, hydrolyzed tannins such as gallotannins, flavonoids and derivatives thereof), carotenoids (lycopene, astaxanthin, zeaxanthin, lutein, etc.), Saponins (isoflavones, ginsaneoids, glycyrrhizic acid, etc.), xanthine derivatives (caffeine, etc.), fatty acids, amino acids, proteins (collagen, elastin, etc.), mucopolysaccharides (hyaluronic acid, chondroitin, dermatan, heparan, heparan, Phosphorus, ketalan, and salts thereof), amino sugars (glucosamine, acetylglucosamine, galactosamine, acetylgalactosamine, neuraminic acid, acetylneuraminic acid, hexosamine, and salts thereof), dietary fiber (indigestible dextrin, alginic acid) , Guar gum, pectin, glucomannan, etc.), oligosaccharides (isomalto-oligosaccharides, cyclic oligosaccharides, etc.), phospholipids and derivatives thereof (phosphatidylcholine, sphingomyelin, ceramide, etc.), sulfur-containing compounds (alliin, sepaene, taurine, Glutathione, methylsulfonylmethane, etc.), sugar alcohol, quinones (coenzyme Q10, etc.), lignans (sesamin, etc.) and animal and plant extracts containing these, root vegetables such as turmeric, ginger, etc. And kale Green leaves, etc. of the Rana family plant, is combined with other food materials. Further, it is molded into capsules such as hard capsules and soft capsules, tablets and pills, or in the form of powders, granules, tea bags and the like. These can be taken as is or dissolved in water, hot water, milk or the like, or the components can be leached depending on the shape or preference.

  Moreover, the extract or powder of the extract of the present invention can be widely applied not only to foods but also to pharmaceuticals, quasi drugs, cosmetics, toiletries and the like. For example, lotion, cosmetic cream, emulsion, pack, hair tonic, shampoo, hair rinse, treatment, body shampoo, facial cleanser, soap, foundation, lipstick, hair restorer, ointment, bath preparation, dentifrice, mouthwash, ship, gel The base material and animal and plant extract which can be used by those skilled in the art can be used.

  The amount of the extract of the present invention added to external preparations such as foods and cosmetics is not particularly limited, but as a food, it is preferably 0.001 to 100% by mass, more preferably 0.01% to 70% by mass. Contained. In addition, as an external preparation, the physiological action of the extract can be obtained by adding 0.00001% by mass to 50% by mass, preferably 0.0001% by mass to 30% by mass in the external preparation. It is.

  Hereinafter, the present invention will be described in more detail, but the present invention is not limited to this range.

Example 1
70 L of 85 vol% ethanol was added to 1 kg of banaba leaf, heated to reflux at 80 ° C. for 1 hour, and filtered under reduced pressure to obtain an extract. Further, 70 L of 85% by volume ethanol was added to the residue, heated to reflux at 80 ° C. for 1 hour, filtered under reduced pressure, and the filtrate was combined with the extract to obtain a crude extract. 100 g of activated carbon carborafine (manufactured by Takeda Pharmaceutical Company Limited) was added to the crude extract, and after refluxing at 80 ° C. for 1 hour, filtration was performed under reduced pressure to obtain a decolorization treatment solution. When this decolorization treatment liquid was concentrated to 10 L under reduced pressure at 60 ° C., the concentration was stopped and left at 20 ° C. overnight, whereupon it separated into a precipitate and a supernatant. A precipitate was collected from this liquid using a centrifuge, and the obtained precipitate was again washed with stirring in 5 L of 30 vol% ethanol at room temperature, and filtered under reduced pressure to obtain a precipitate. This precipitate was dried overnight at 60 ° C. under reduced pressure to obtain 15 g as a dried product. When the corosolic acid content in the obtained yellow dried product was measured using high performance liquid chromatography, the corosolic acid content was 9.8%.

Claims (1)

Extracting banaba leaves with an aqueous solution containing 60% to 100% by volume of ethanol to obtain a crude extract; the obtained crude extract is 10-20% by mass with respect to 100 parts by mass of the dry mass of banaba leaves. A step of obtaining a treatment liquid treated with activated carbon to increase the content of corosolic acid; a step of separating the precipitate in the concentrated liquid obtained by concentration and collecting the precipitate washed with an aqueous ethanol solution of 30% by volume or less The manufacturing method of the banaba leaf extract containing 9 mass% or more corosolic acid in conversion of the dry mass which contains.