Virus inactivator

Abstract

We will provide a new virus inactivator. [Solution] A virus inactivator comprising a powder containing the oil extraction residue of coniferous tree leaves.

Description

Technical Field

[0001] The present invention relates to a virus inactivator comprising a powder containing oil extraction residues of coniferous tree leaves.

Background Art

[0002] Some enveloped viruses have a profound impact on humans and poultry. In particular, avian influenza is a disease of poultry caused by infection with avian influenza virus (avian-derived influenza A virus). When highly pathogenic avian influenza occurs, culling of all birds becomes inevitable, causing huge damage to the poultry industry.

[0003] In addition to the damage to poultry, there is also a concern about the risk of the emergence of a new influenza virus with human-to-human infectivity due to genetic reassortment between multiple virus strains. As a serious global social problem, countermeasures are strongly demanded.

[0004] Various avian influenza virus inactivators have been proposed. For example, in Patent Document 1, an antiviral agent using an extract from the leaves of fir trees is disclosed, and in Patent Document 2, an anti-influenza virus composition using an extract from the wood of hazel is disclosed.

[0005] However, plant-derived inactivators are liquid at room temperature regardless of their lipid solubility or water solubility, and it is difficult to apply them to tangible articles such as by coating or kneading into fiber products or plastics, and their applications have not been widespread.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Summary of the Invention

[0007] Therefore, the object of the present invention is to provide a novel virus inactivating agent. [Means for solving the problem]

[0008] The inventors of this invention have been diligently conducting research to achieve the above objectives, and have discovered that a powder containing essential oil extraction residue from coniferous tree leaves can inactivate enveloped viruses such as avian influenza virus, thus completing the present invention.

[0009] In other words, the present invention is as follows: [1] A virus inactivator consisting of a powder containing the oil extract residue of coniferous tree leaves. [2] The virus inactivator described in [1], wherein the leaves of coniferous trees are selected from the group consisting of the genus Chamaecyparis in the family Cupressaceae, the genus Cryptomeria in the family Cupressaceae, the genus Abies in the family Pinaceae, the genus Sciadopitys in the family Sciadopityaceae, and the genus Thujopsis in the family Cupressaceae. [3] The virus inactivator described in section [1] or [2], wherein the coniferous tree leaves are those of trees of the genus Abies in the family Pinaceae. [4] The leaves of trees of the genus Abies in the family Pinaceae, such as the leaves of Abies sachalinensis [3] are the virus inactivators described. [5] The virus inactivator according to any one of [1] to [4], wherein the oil extraction residue is the residue after oil extraction with a polar solvent. [6] The virus inactivator according to any one of [1] to [4], wherein the oil extraction residue is the residue obtained by heating and distilling the leaves of trees of the genus Abies in the family Pinaceae under reduced pressure and removing the distillate. [7] A virus inactivator described in [6] wherein heating is performed by microwave heating. [8] A method for producing a virus inactivator, characterized by extracting oil from coniferous tree leaves and then obtaining a powder containing the oil extraction residue. A virus-inactivating resin obtained by mixing a virus inactivating agent described in any one of [9][1] to [7] with a resin. A virus-inactivating product molded from the virus-inactivating resin described in

[10] [9]. [Effects of the Invention]

[0010] The virus inactivator of the present invention has excellent inactivating activity against viruses, and in particular, excellent inactivating activity against enveloped viruses such as avian influenza viruses, making it possible to suppress the spread of viral infection. [Modes for carrying out the invention]

[0011] The virus inactivator of the present invention consists of a powder containing the oil extraction residue of coniferous tree leaves. Here, virus inactivation refers to, for example, performing a virus inactivation test based on the examples and comparing the virus titer (TCID) with that of a control. 50 This refers to a situation where the percentage of inactivated virus calculated from the difference in ( / mL) is 90% or more after 24 hours, preferably 90% or more after 4 hours, and even more preferably 90% or more after 1 hour.

[0012] The above-mentioned coniferous trees are not particularly limited, but examples include trees of the genus Chamaecyparis in the cypress family, the genus Thuja in the cypress family, the genus Juniper in the cypress family, the genus Cryptomeria in the cypress family, the genus Abies in the pine family, the genus Cedrus in the pine family, the genus Picea in the pine family, the genus Pinus in the pine family, the genus Larch in the pine family, the genus Hemlock in the pine family, the genus Sciadopitys in the Sciadopityaceae family, the genus Torreya in the yew family, and the genus Thuja in the cypress family.

[0013] Trees belonging to the genus Chamaecyparis in the family Cupressaceae include Japanese cypress (Hinoki), Taiwanese cypress (Hinoki), Western cypress (Hinoki), Lawson cypress (Hinoki), Chamaecyparis obtusa (Hinoki), Sawara cypress (Hinoki), Peacock cypress (Hinoki), Golden Chamaecyparis obtusa (Hinoki), Water cypress (Hinoki), Thread cypress (Hinoki), Golden cypress (Hinoki), Davallia cypress (Hinoki), Golden Davallia cypress (Hinoki), and Japanese cedar (Hinoki). Trees belonging to the genus Thuja in the family Cupressaceae include Japanese cypress (Hinoki), Japanese cedar (Hinoki), Japanese cedar (Hinoki), Pencil cedar (Hinoki), and Okinawa cedar (Hinoki). Trees belonging to the genus Cryptomeria in the family Cupressaceae include Japanese cedar (Sugi), Japanese cedar (Ashisugi), Japanese cedar (Enkosugi), Japanese cedar (Yoresugi), Golden cedar (Sugi), Japanese cedar (Sekkasugi), and Green cedar (Midorisugi).

[0014] Examples of trees in the genus Abies of the Pinaceae family include Abies sachalinensis, Abies firma, Abies mariesii, Picea glehnii, Picea obovata, Picea jezoensis, Abies balsamea, Abies nephrolepis, Abies procera, Abies amabilis, Picea pungens, Sequoiadendron giganteum, Pseudotsuga menziesii, etc. Examples of trees in the genus Keteleeria of the Pinaceae family include Keteleeria davidiana, Keteleeria fortunei, etc. Examples of trees in the genus Pinus of the Pinaceae family include Pinus densiflora, Pinus taiwanensis, Pinus strobus, Pinus cembra, etc. Examples of trees in the genus Larix of the Pinaceae family include Larix gmelinii, etc. Examples of trees in the genus Tsuga of the Pinaceae family include Tsuga sieboldii, etc.

[0015] Examples of trees in the genus Castanopsis of the Fagaceae family include Castanopsis sieboldii, etc.

[0016] Examples of trees in the genus Aucuba of the Garryaceae family include Aucuba japonica, etc.

[0017] Examples of trees in the genus Thujopsis of the Cupressaceae family include Thujopsis dolabrata, Thujopsis sutchuenensis, Thujopsis hondai, Thujopsis lanceolata, etc.

[0018] Among the above-mentioned coniferous trees, trees in the genus Chamaecyparis of the Cupressaceae family, the genus Cryptomeria of the Cupressaceae family, the genus Abies of the Pinaceae family, the genus Castanopsis of the Fagaceae family, and the genus Thujopsis of the Cupressaceae family are preferred. They are widely distributed in Japan and are easily available. Therefore, trees in the genus Abies of the Pinaceae family are more preferred, and Abies sachalinensis of the genus Abies of the Pinaceae family is particularly preferred. These coniferous trees may be combined in multiple species.

[0019] The above-mentioned coniferous tree leaves may include, in addition to the leaf parts of coniferous trees, branch and trunk parts. Also, the coniferous tree leaves may be used as they are, but it is preferable to crush or grind them using a crusher, a grinder, or the like before the extraction described later. The crushed or ground coniferous tree leaves are not particularly limited, and may be, for example, flakes or chips about 15 to 60 mm in length and 2 to 10 mm in thickness, or granular with a particle size of about 0.5 to 2 mm.

[0020] The powder containing the oil extraction residue from coniferous leaves after extracting oil from the coniferous leaves is not particularly limited as long as it is obtained as a powder containing the oil extraction residue after extracting oil from coniferous leaves. Examples include the residue after extracting oil from coniferous leaves with a polar solvent, and the residue obtained by heating and distilling coniferous leaves under reduced pressure and removing the distillate. Furthermore, the powder containing the oil extraction residue from coniferous tree leaves according to the present invention does not need to have all the oil contained in the coniferous tree leaves completely removed. For example, it may contain residual oil after applying the general extraction and distillation method described later. The weight ratio of oil content before and after applying the extraction and distillation method is not particularly limited, but for example, {weight of oil after application (g)} / {weight of oil before application (g)} = 50% or less, preferably 30% or less.

[0021] More specifically, the residue remaining after extracting oil from coniferous tree leaves using polar solvents is the residue of the raw material (leaves) obtained by distilling coniferous tree leaves as the raw material using a distillation apparatus with polar solvents such as water, ethanol, methanol, butyl alcohol, ethylene glycol, propylene glycol, glycerin, halogenated solvents such as chloroform, ether solvents such as dioxane, carbonyl solvents such as acetone and ethyl acetate, and mixtures thereof, and then removing the distillate (purified water or essential oil).

[0022] The residue obtained by heating and distilling coniferous tree leaves under reduced pressure and then distilling off the distillate is, more specifically, the residue of the raw material (leaves) obtained by heating and distilling coniferous tree leaves under reduced pressure using microwaves, heaters, etc., and then distilling off the distillate (purified water or essential oil). In particular, this method of heating with microwaves under reduced pressure and distilling off the distillate (purified water or essential oil) is called vacuum distillation.

[0023] This vacuum distillation method can be carried out using, for example, a microwave distillation apparatus as described in the international publication WO2010 / 098440. In this vacuum distillation method, the pressure inside the distillation vessel should be set to 1 to 95 kPa, preferably 5 to 80 kPa, and particularly preferably 10 to 60 kPa. The vapor temperature at this time will be 40 to 100°C.

[0024] In the vacuum distillation method, coniferous tree leaves are heated under reduced pressure using microwaves to remove the distillate, and then a drying process is preferably carried out at atmospheric pressure to remove moisture. The drying temperature and drying time are not particularly limited, but for example, it can be done at 50-80°C for 1-5 hours. The moisture content of the powder obtained after the drying process is not particularly limited, but for example, it is about 3-15% by weight.

[0025] The virus inactivator obtained in this way has excellent inactivating activity against viruses, and in particular has excellent inactivating activity against enveloped viruses such as avian influenza virus, thus being able to suppress the spread of viral infection. Furthermore, the virus inactivator of this invention can inactivate viruses at a neutral pH of around 7.

[0026] The powder containing the oil extraction residue from coniferous tree leaves can be used as is as the virus inactivator of the present invention, and the virus inactivator of the present invention can be used in the same applications as conventional virus inactivators. Preferred applications of the virus inactivator of the present invention include its use as a material constituting industrial materials and consumer goods, since the virus inactivator of the present invention is solid at room temperature. If a material containing such a virus inactivator of the present invention is used, viruses can be inactivated when they come into contact with it or when viruses floating in the air are adsorbed onto it.

[0027] When the virus inactivating agent of the present invention is used in materials that constitute industrial materials or consumer goods, the virus inactivating agent of the present invention can be mixed with, for example, fibers, woven fabrics, nonwoven fabrics, or resins, and molded into a product by any processing such as papermaking, coating, extrusion, or injection molding. Alternatively, a solution in which the virus inactivating agent of the present invention is dispersed in a solvent can be used, and if necessary, together with adhesive components, etc., to coat an existing product with the virus inactivating agent of the present invention by spraying, coating, etc.

[0028] Examples of solvents capable of dispersing the virus inactivator of the present invention include water, alcohol-based solvents such as ethanol, isopropyl alcohol, and propyl alcohol, glycol-based solvents such as propylene glycol and ethylene glycol, and glycol ether-based solvents such as ethylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene alcohol monoethyl ether, and 3-methoxy-3-methyl-1-butanol. The solvent may contain a powder containing the oil extraction residue of coniferous tree leaves at an amount of approximately 0.01 to 99% by mass.

[0029] When using the virus inactivating agent of the present invention as a material for industrial materials or consumer goods, it is preferable to use a virus-inactivated fabric obtained by mixing the virus inactivating agent of the present invention with fibers. By using the virus inactivating agent of the present invention, a uniform fabric that does not have oil seepage can be obtained. The content of the virus inactivating agent in this virus-inactivated fabric can be appropriately set according to the purpose.

[0030] When using the virus inactivating agent of the present invention as a material for industrial materials or consumer goods, it is also preferable to use a virus-inactivating resin in which the virus inactivating agent of the present invention is mixed with a resin. When the virus inactivating agent of the present invention is mixed with a resin, it is uniform and does not produce oil separation. The content of the virus inactivating agent in this virus-inactivating resin can be appropriately set according to the purpose.

[0031] The material containing the virus inactivating agent of the present invention is preferably molded into a virus inactivating product. Examples of industrial materials containing such materials include flooring, wall materials, wallpaper and other building materials for poultry houses, residences and other buildings, bedding, curtains and other sheet materials. Examples of consumer goods containing such materials include masks, doorknobs, handrails, bath mats, desks, chairs, underlays, rulers, garbage bags, blue sheets, tiles, toys, and the like.

[0032] The products that can be coated with the virus inactivating agent of the present invention are not particularly limited. [Examples]

[0033] The present invention will be described in more detail below with reference to examples, but the present invention is not limited in any way by these examples.

[0034] Example 1 Preparation of powder containing oil extraction residue from fir tree leaves: As raw material, fir leaves were used, and distillation was carried out as follows: Approximately 50 kg of fir leaves, crushed to an average length of 30 mm and a thickness of 5 mm using a crushing mill (manufactured by KYB Corporation), were placed in the distillation tank of a microwave distillation apparatus. While stirring, the pressure inside the distillation tank was maintained under reduced pressure conditions of approximately 20 kilopascals (steam temperature approximately 67°C), and distillation was carried out by microwave irradiation for 1 hour. After distillation, 20 kg of extraction residue was obtained after the oil content of the fir leaves had been extracted. The distillate was recovered from the distillate extraction tube connected to the distillation tank. Subsequently, the extraction residue was placed in a drying mill, dried and pulverized at 60°C for 2 hours, and then sieved to obtain 5 kg of powder with an average particle size of approximately 2 mm.

[0035] Example 2 Virus inactivation test: A screw-cap tube contains 10 mg of the powder containing the oil extraction residue from fir leaves prepared in Example 1, and 1 ml of virus solution (evaluated virus: H5N1 subtype highly pathogenic avian influenza virus (A / white-tailed eagle / Japan / OU-1 / 2022 strain: clade 2.3.4.4b): virus titer: approximately 6.75 log 10 TCID 50 The solution was added ( / ml) and thoroughly mixed by pipetting. Then, after mixing by inversion at 25°C for a set period (30 minutes, 1 hour, 4 hours, 24 hours), the tube was centrifuged using a bench centrifuge at 13,000 rpm at 4°C for 5 minutes. After centrifugation, the supernatant was serially diluted 10-fold and inoculated into MDCK cells. For comparison, a powder obtained by crushing fir wood was used, and a sample was prepared under the same conditions and inoculated into MDCK cells in the same manner. After culturing cells at 37°C for three days, the viral titer of the virus solution was calculated based on the strength of the cytopathic effect observed in the cells, after reacting with each powder for 30 minutes, 1 hour, 4 hours, and 24 hours (8 samples each). The average viral titer of each sample was taken, and the difference in the average value between the sample and the control was calculated at each time interval. Based on this difference, the percentage of inactivated virus was calculated using the following formula.

[0036]

number

[0037] These results are shown in Table 1 (in Table 1, the system of "oil extraction residue from fir leaves prepared in the examples" is labeled "leaf powder," and the system of "powder obtained by crushing fir wood" used for comparison is labeled "wood powder").

[0038] [Table 1] Note: The mean, standard deviation, and difference of means in the table are (value × log 10 TICD 50 ( / mL)

[0039] From these results, it was found that powder containing oil extract residue from fir tree leaves can inactivate highly pathogenic avian influenza virus.

[0040] Furthermore, using the powder containing the oil extract residue of fir leaves prepared in Example 1, and a solution prepared under the same conditions as the virus solution except that it did not contain the virus, and under the same conditions as in Example 2, a sample was prepared, and after centrifugation, the pH of the supernatant was measured to be 7.0. Therefore, it was found that the powder containing the oil extract residue of fir leaves can inactivate viruses in a neutral state, independent of pH.

[0041] Implementation Example 3 Preparation of resin molded products: 9 kg of polypropylene pellets and 1 kg of powder containing the oil extraction residue from fir leaves prepared in Example 1 were supplied to an extruder and melt-kneaded at 180°C. The resin composition was then extruded from the extruder, and after the extruded resin composition was cooled, a cubic test specimen with sides of 100 mm was prepared.

[0042] Implementation Example 4 Weight: 40g / m 2 The powder containing the oil extract residue from fir leaves prepared in Example 1 was dispersed in water with a water-soluble binder on the cellulose nonwoven fabric to form a slurry. The resulting slurry was coated with a knife coater to a basis weight of 40 g / m². 2 The cellulose nonwoven fabric was coated and dried to prepare test specimens. The obtained test specimens contained a powder of 20 g / m², including the oil extraction residue from fir leaves. 2 This was the amount of coating applied.

[0043] The test specimens obtained in Examples 3 and 4 were all uniform, and no oil separation or oil stains were observed. [Industrial applicability]

[0044] The virus inactivator of the present invention can be used to inactivate viruses.

Claims

1. A virus inactivator consisting of a powder containing the oil extraction residue from coniferous tree leaves.

2. The virus inactivator according to claim 1, wherein the coniferous tree leaves are those of trees selected from the group consisting of the genus Chamaecyparis in the family Cupressaceae, the genus Cryptomeria in the family Cupressaceae, the genus Abies in the family Pinaceae, the genus Sciadopitys in the family Sciadopityaceae, and the genus Thujopsis in the family Cupressaceae.

3. The virus inactivator according to claim 1, wherein the coniferous tree leaves are the leaves of trees belonging to the genus Abies in the family Pinaceae.

4. The virus inactivator according to claim 3, wherein the leaves of a tree of the genus Abies in the family Pinaceae are those of Abies sachalinensis.

5. The virus inactivator according to claim 1, wherein the oil extraction residue is the residue after oil extraction with a polar solvent.

6. The virus inactivator according to claim 1, wherein the oil extraction residue is the residue obtained by heating and distilling the leaves of a tree of the genus Abies in the family Pinaceae under reduced pressure and removing the distillate.

7. The virus inactivator according to claim 6, wherein the heating is performed by microwave heating.

8. A method for producing a virus inactivator, characterized by extracting oil from coniferous tree leaves and then obtaining a powder containing the oil extraction residue.

9. A virus inactivating material obtained by mixing a virus inactivating agent according to any one of claims 1 to 7 with a fiber, woven fabric, nonwoven fabric, or resin.

10. A virus-inactivating product obtained by molding the virus-inactivating material described in claim 9.

Images