JP7801717B2 - Neutral lipid absorption inhibitor and processed food using ginger leaves - Google Patents

Description

The present invention relates to a neutral lipid absorption inhibitor and processed food based on an extract from the leaves of Zingiber mioga (scientific name: Zingiber mioga), a plant of the Zingiberaceae family.

Myoga (scientific name: Zingiber mioga) is a perennial plant of the ginger genus in the ginger family (Zingiberaceae), native to East Asia, including Japan. It is widely cultivated in Japan for food, and because of its distinctive refreshing fragrance and gorgeous crimson color, the flowering ginger (the flower spike before flowering) and the myoga mushroom (the stems and leaves that grow separately from the underground stems) are used as aromatic vegetables. Furthermore, as a folk remedy, myoga is used for its effects of stimulating the brain, waking up from drowsiness, improving blood flow, inducing sweating, increasing appetite, and acting as a detoxifier.

On the other hand, the leaves of the myoga plant are used in local dishes in the Tohoku region, such as Iwate and Miyagi prefectures, to make "grilled myoga leaves," in which a mixture of wheat flour or glutinous rice flour, sugar, and miso is wrapped in the leaves and baked. However, these parts are not commonly eaten, and much of them are discarded as an unused resource.

For example, Patent Document 1 discloses that an aqueous extract of Myoga (Zingiber mioga) has antihypertensive, central nervous system depressant, cholinergic nervous stimulant, cardiac depressant, and anti-inflammatory effects. Furthermore, Patent Document 2 discloses that Myoga trial, a labdane-type diterpene compound obtained from a hexane extract of Myoga (Zingiber mioga), can be used as an antibacterial, antithrombotic, and anti-inflammatory agent.

Furthermore, Patent Document 3 discloses that galanal A or galanal B, which are labdane-type diterpene compounds obtained from the flower spikes of Zingiber mioga, or a mixture of these and Zingiber mioga, can be used as anti-aging agents.

Furthermore, Patent Document 4 discloses that an extract obtained from the flower spikes of Zingiber mioga can be used as a gastric mucosa protective agent.

Non-Patent Document 1 also discloses that myoga dial, obtained from an ethyl acetate extract of myoga, has antibacterial, cholesterol-lowering, and platelet aggregation-inhibiting effects, and is also a pungent component.

Furthermore, Non-Patent Document 2 discloses that myoga dial and myoga trialal promote the activation of TRPA1 receptors and TRPV1 receptors, which are TRP (Transient Receptor Potential) channels. Because TRPA1 receptors and TRPV1 receptors are involved in body heat production, myoga dial and myoga trialal are thought to have the effect of promoting body heat production.

Japanese Unexamined Patent Publication No. 55-009021 Japanese Patent Application Laid-Open No. 2006-241068 JP 2014-152118 A Japanese Patent Application Laid-Open No. 2019-199433

Biosci. Biotechnol. Biochem. , 2002, 66(12), p. 2698-2700 Life Sci. , 2009, 85, p. 60-69 Bioorg. Med. Chem. Lett, 2003, 13, p. 1101-1106 J. Nat. Prod. , 2005, 68, p. 1360-1365

The present invention aims to provide a drug (neutral lipid absorption inhibitor) obtained from the leaves of Zingiber mioga (ginger). The present invention also aims to provide a human or veterinary medicine containing the drug, and a processed food containing the neutral lipid absorption inhibitor.

In developing a neutral lipid absorption inhibitor using natural plants, the inventors conducted extensive research to identify useful plants. Specifically, they investigated the inhibitory effect of mioga leaves (scientific name: Zingiber mioga), a plant of the Zingiberaceae family, extracts obtained by extracting mioga leaves with water or lower alcohols, or extracts obtained by concentrating the extracts, on olive oil-induced elevation of blood neutral lipids in mice as an index of neutral lipid absorption inhibitory activity. As a result, they found that mioga leaves, extracts obtained by extracting mioga leaves with water or lower alcohols, or extracts exhibit neutral lipid absorption inhibitory activity, leading to the completion of the present invention.

More specifically, the neutral lipid absorption inhibitor according to the present invention comprises:
The product is characterized by containing, as an active ingredient, an extract obtained by extracting the leaves of Myoga with water, a lower alcohol or a water-containing substance thereof, or an extract obtained by concentrating the extract.

In addition, the processed food for inhibiting neutral lipid absorption according to the present invention comprises:
The product contains, as an active ingredient, an extract obtained by extracting the leaves of Myoga with water, a lower alcohol or a water-containing substance thereof, or an extract obtained by concentrating the extract, and is characterized in that it does not contain the substance of Myoga when made into a final product.

The present invention provides a novel neutral lipid absorption inhibitor. The neutral lipid absorption inhibitor of the present invention is a natural plant-based neutral lipid absorption inhibitor that is safe for the body and economical to use, and is effective as an alternative to conventional synthetic drug-based neutral lipid absorption inhibitors such as clofibrate. Specifically, the extract prepared from the leaves of Zingiber mioga (scientific name: Zingiber mioga), a plant of the Zingiberaceae family (ginger family), or an extract obtained by concentrating the extract, inhibits the absorption of ingested neutral lipids and suppresses increases in blood neutral lipid levels. Therefore, it is effective as a natural plant-based neutral lipid absorption inhibitor that is safe for the body and economical to use.

1 is a graph showing blood neutral lipid concentrations in olive oil-loaded mice treated with a neutral lipid absorption inhibitor (ethanol extract from ginger leaves) according to the present invention.

The neutral lipid absorption inhibitor of the present invention will be explained below with reference to drawings and examples. Note that the following explanation exemplifies one embodiment of the present invention and one example, and the present invention is not limited to the following explanation. The following explanation can be modified within the scope of the present invention.

The neutral lipid absorption inhibitor of the present invention contains an extract extracted from the leaves of Zingiber mioga (scientific name: Zingiber mioga; hereinafter simply referred to as "Zingiber mioga"), a plant of the Zingiberaceae family.

In Japan, myoga is produced in Kochi Prefecture, Nara Prefecture, Gunma Prefecture, Akita Prefecture, Yamagata Prefecture, Wakayama Prefecture, Nagano Prefecture, Toyama Prefecture, Aomori Prefecture, Niigata Prefecture, and other prefectures. There are slight differences in the amount and types of ingredients contained in myoga depending on the place of origin and cultivation method. However, ginger grown in any region can be used.

The leaves of the myoga plant are best used from summer to autumn (July to November) each year after they germinate. Dead leaves should be excluded.

General extraction methods can be used to extract an extract from ginger leaves. Specifically, chopped or powdered plant matter (hereinafter referred to as the "subject to extraction") is extracted with water or a lower alcohol (e.g., methanol, ethanol, butanol, isopropanol, etc.), or a mixture of these (hereinafter referred to as the "solvent, etc.") for either (1) a day or night for cold immersion extraction at room temperature, or (2) 2-3 hours for hot extraction in a boiling water bath. In this case, the solvent, etc., is used in an amount at least 10 times (by weight) the amount of the subject to extraction. The solvent, etc., can also be referred to as water, a lower alcohol, or a hydrate thereof. Note that lower alcohol here refers to an alcohol with 5 or fewer carbon atoms.

The extract is then filtered, and the same amount of solvent is added to the residue, and the same procedure is repeated two or three times. The extract obtained after each procedure is combined and concentrated under reduced pressure to obtain the extract (extract).

This extract can be used in various forms, such as liquids, granules, tablets, and capsules, together with pharmaceutically acceptable salts, excipients, preservatives, coloring agents, flavoring agents, etc., using methods known in the field of pharmaceutical or processed food manufacturing.

The amount of the extract or the extract obtained by concentrating the extract used as an active ingredient in the pharmaceutical or processed food of the present invention is adjusted appropriately depending on factors such as the degree of concentration and purification, activity, the purpose of use, the target disease or severity of symptoms, and the weight and age of the user. For example, when used as a pharmaceutical for adults, it is often appropriate to use approximately 1 mg to 20 g of the extract or extract per administration, and adjust the amount within this range depending on factors such as the degree of purification and water content.

When used in processed foods, it is often appropriate to add an amount that does not adversely affect the taste or appearance of the processed food, for example, 1 mg to 20 g of the extract or an extract obtained by concentrating the extract per 1 kg of the processed food. Processed foods also include so-called "health foods."

Furthermore, processed foods do not include those in which the flesh of the myoga plant (halibutsunflower, ginger mushrooms, and leaves) remains in the final product. That is, processed foods in which the flesh of the myoga plant has been ground up, boiled, heated, baked, or pickled in lees or miso paste are excluded. In other words, the processed foods of the present invention are processed foods in which the flesh of the myoga plant is not contained in the final product, but which contain, as an active ingredient, an extract obtained by extracting the leaves of the myoga plant with water, a lower alcohol, or a hydrate thereof, or an extract obtained by concentrating the extract.

The present invention will be explained in more detail below using examples. It goes without saying that the present invention is not limited to the examples.

Example 1: Extraction of Dried Zingiber mioga Leaves Dried Zingiber mioga leaves (102.65 g) were thawed at room temperature and then crushed in a juicer mixer with an appropriate amount of Japanese Pharmacopoeia ethanol (manufactured by Amakasu Chemical Industry Co., Ltd.) to obtain the extract. To this extract, approximately 2.0 L of Japanese Pharmacopoeia ethanol (approximately 20 times the wet weight) was added as a solvent, and the extract was heated under reflux for 3 hours. The extract was then filtered through pleated filter paper (Advantec Co., Ltd., No. 2 filter paper), and fresh Japanese Pharmacopoeia ethanol was added to the residue, and the same extraction procedure was repeated a total of three times. The extracts obtained from each extraction procedure were combined, and the solvent was removed under reduced pressure using a rotary evaporator to obtain 10.74 g of ethanol extract (10.46%, yield from dried leaves).

[Example 2] Verification of the inhibitory effect on olive oil-induced elevation of blood neutral lipids in mice. Male ddY rats (body weight approximately 25-30 g) fasted for 24-26 hours were orally administered an ethanol extract of ginger leaves (1000 mg/kg, the dose expressed in mg per kg of mouse body weight) and olive oil (5 mL per kg of rat body weight). This corresponds to a human equivalent dose (HED) of 81.4 mg/kg. Blood was collected from the orbital vein 2, 4, and 6 hours after olive oil administration, and serum neutral lipid levels were measured using a commercially available kit, "Triglyceride E Test Wako (Fujifilm Wako Pure Chemical Industries)" (as described in Non-Patent Document 4).

The ginger leaf ethanol extract according to the present invention was prepared as the test substance, and this is referred to as the ginger administration group. A control group was also run in which no test substance was administered. This is referred to as the control group. A normal group was also run in which the same amount of saline was administered instead of olive oil. This is referred to as the normal group. The normal group was the group that received saline and ginger leaf ethanol extract.

Therefore, three sample groups were formed: a normal group, a control group, and a ginger-administered group. Each group consisted of n=8-9.

The results are shown in Figure 1. The vertical axis represents blood neutral lipid concentrations (mg/dL), and the horizontal axis represents the time (h) elapsed since olive oil administration. The normal group is represented by "Normal" (dashed line), the control group by "Control" (dash-dotted line), and the ginger-administered group is represented by a dose of "1000 mg/kg" (solid line). Note that "*" represents p<0.05, and "**" represents p<0.01.

Referring to Figure 1, blood neutral lipid concentrations two hours after administration were significantly reduced in the group administered with Myoga compared to the control group. Based on the above, the neutral lipid absorption inhibitor of the present invention is effective when taken at least before meals.

From the above, it can be seen that the ginger extract of the present invention is effective as a neutral lipid absorption inhibitor.

The neutral lipid absorption inhibitor of the present invention can be suitably used as a drug or processed food that suppresses the absorption of lipids ingested through food, etc., and inhibits increases in blood neutral lipid levels.

Claims (2)

A neutral lipid absorption inhibitor characterized by containing as an active ingredient an extract obtained by extracting ginger leaves with water, a lower alcohol, or a water-containing substance thereof, or an extract obtained by concentrating said extract. A processed food for inhibiting neutral lipid absorption, characterized in that it contains as an active ingredient an extract obtained by extracting ginger leaves with water, a lower alcohol, or a water-containing substance thereof, or an extract obtained by concentrating said extract, and that the final product does not contain any actual ginger.