JP7743956B2 - Novel coronavirus (SARS-CoV-2) inactivating composition - Google Patents

Description

The present invention relates to a novel coronavirus (SARS-CoV-2) inactivation composition.

As a response to the infectious disease (COVID-19) caused by the novel coronavirus (SARS-CoV-2, also known as SARS coronavirus-2) that emerged in 2019, Japan's Ministry of Health, Labor and Welfare has published a guide on how to disinfect and sterilize the novel coronavirus on its website. The guide lists methods that are effective against the virus, including water and soap, hot water (80°C for 10 minutes), alcohol-based disinfectant, sodium hypochlorite solution, surfactants (detergents) other than those for hands, hypochlorous acid water, and chlorous acid water.
However, alcohol disinfectants, sodium hypochlorite aqueous solutions, detergents, hypochlorous acid water, and chlorous acid water all have a strong chemical odor and can have an adverse effect on the human body, so they must be handled with care.

Furthermore, known inactivators for the novel coronavirus include linear alkylbenzene sulfonates and inactivators containing as an active ingredient at least one polyoxyethylene alkyl ether selected from polyoxyethylene alkyl ethers having 12 carbon atoms in the alkyl group and 7 moles of ethylene oxide added, and polyoxyethylene alkyl ethers having 12 carbon atoms in the alkyl group and 8 moles of ethylene oxide added (Patent Document 1).
However, when the active ingredients are chemicals such as those mentioned above, they are effective in inactivating the new coronavirus at low concentrations, and although the chemical smell is somewhat reduced, they are still chemical products and therefore require careful handling.

In addition, many known disinfectants have a chemical odor, which can be stressful for some people when used over a wide area or in large quantities.

Patent No. 6795720

The object of the present invention is to provide a novel coronavirus inactivator composition that is composed of highly safe ingredients, exhibits excellent SARS coronavirus-2 inactivation effects, and has the aroma effect of cypress oil.

To achieve the above objective, the inventors conducted extensive research and discovered that a composition consisting of cypress oil, grapefruit seed extract, a vegetable oil-derived emulsifier, and water has the effect of inactivating SARS coronavirus-2 and also has the aroma effect of cypress oil, leading to the completion of the present invention.

That is, the gist of the present invention is
[1] A novel coronavirus (SARS-CoV-2) inactivating composition containing cypress oil, grapefruit seed extract, and a vegetable oil-derived emulsifier as active ingredients;
[2] 0.1 to 10% by weight of cypress oil,
Grapefruit seed extract 0.05 to 5% by weight,
The novel coronavirus (SARS-CoV-2) inactivating composition according to [1], which contains 0.1 to 8% by weight of a vegetable oil-derived emulsifier, the remainder being water.
[3] The novel coronavirus (SARS-CoV-2) inactivating composition according to [1] or [2], wherein the cypress oil is cypress essential oil extracted from domestic cypress.
[4] The novel coronavirus (SARS-CoV-2) inactivating composition according to any one of [1] to [3] above, which has a pH of 3.5 to 6.0.

The novel coronavirus (SARS-CoV-2) inactivating composition of the present invention is composed of highly safe ingredients and does not cause problems such as deterioration when attached to the human or animal body, textiles, textile products, etc. Therefore, it can be used on a wide range of materials in homes and business facilities, including floors, walls, windows, doors, food processing equipment, medical equipment, various furniture, home appliances, instruments, tools, etc. in restrooms, toilets, bathrooms, washrooms, shower basins, kitchens, living rooms, bedrooms, etc., hard surfaces such as toys, clothing, towels, masks, sofas, curtains, carpets, bedding, cushions, shoes, bags, and other textile products. Furthermore, because the novel coronavirus inactivating composition of the present invention has a cypress scent derived from cypress oil, the aromatic effects of cypress oil can also be expected.

The present invention is described in more detail below.

The novel coronavirus (SARS-CoV-2) inactivating composition of the present invention (hereinafter referred to as the "composition of the present invention") is characterized by containing cypress oil, grapefruit seed extract, and a vegetable oil-derived emulsifier as active ingredients.

In the present invention, the term "active ingredient" refers to an ingredient other than the solvent water. In the composition of the present invention, the total content of cypress oil, grapefruit seed extract, and vegetable oil-derived emulsifier in the active ingredient may be 80% by weight or more, and this total content may be 90% by weight or more, or even 100% by weight.

In the composition of the present invention, cypress oil is a component that exerts the novel coronavirus inactivation effect and aromatic effect.

In the present invention, the novel coronavirus inactivation effect refers to the effect of inactivating the novel coronavirus, and can be evaluated by the method described in the Examples below.

In addition, cypress oil has traditionally been used as an aromatic oil that has a scent reminiscent of forest bathing, and because it contains monoterpenes and sesquiterpenes, it has a refreshing and relaxing effect and is effective in relieving fatigue and stress.
For example, it is known that smelling the scent of cypress leaf essential oil reduces blood flow to the brain and stimulates parasympathetic nervous activity, which is known to increase in a relaxed state, thereby relaxing the human body (Journal of Physiological Anthropology, 34(1):44, Dec 2015, DOI).
The composition of the present invention allows the user to feel the scent of cypress, and therefore provides the aromatic effect of cypress oil.

The cypress oil is extracted by steam distillation from the branches, leaves, roots, bark, resin, etc. of coniferous trees of the genus Chamae in the Cupressaceae family. Any oil containing terpenoids as a main component may be used.
Examples of trees that can be used as a raw material for the cypress oil include Japanese cypress, which is distributed in Japan, and Taiwanese cypress and Taiwanese red cypress, which are distributed in Taiwan.
Among these, cypress essential oil extracted from domestic cypress trees distributed in Japan is preferable, as it is easy to obtain and can easily exert its novel coronavirus inactivation effect and aromatic effect.

The content of the cypress oil in the composition of the present invention is preferably 0.1 to 10% by weight, from the viewpoint of being able to exert the aromatic effects of cypress oil in addition to its novel coronavirus inactivation effect. The lower limit of the content is more preferably 0.5% by weight or more, and the upper limit of the content is more preferably 8% by weight or less.

In the composition of the present invention, grapefruit seed extract is a component that exerts the effect of inactivating the novel coronavirus.
The grapefruit seed extract is a naturally occurring antibacterial component known to have bactericidal and antibacterial activity. In addition, the grapefruit seed extract is water-soluble and has no distinctive odor, which makes it easy to achieve the aroma effect of the cypress oil. The grapefruit seed extract may be any commercially available product, and is not particularly limited.

The content of the grapefruit seed extract in the composition of the present invention is preferably 0.05 to 5% by weight, from the viewpoint of easily exerting the novel coronavirus inactivating effect. The lower limit of the content is preferably 0.1% by weight or more, and the upper limit of the content is preferably 3% by weight or less.

The vegetable oil-derived emulsifier is used to emulsify the cypress oil in water, which is the solvent. Examples of vegetable oil-derived emulsifiers include, but are not limited to, emulsifiers made from plant-derived raw materials (such as coconut, palm, rapeseed, corn, and wheat) and emulsifiers derived from sunflower oil. These can be used alone or in combination of two or more.

The content of the vegetable oil-derived emulsifier in the composition of the present invention is preferably 0.1 to 8% by weight, from the viewpoint of efficiently emulsifying cypress oil. The lower limit of the content is more preferably 0.3% by weight or more, and the upper limit of the content is more preferably 5% by weight or less.

The composition of the present invention contains the cypress oil, the grapefruit seed extract, and the vegetable oil-derived emulsifier as active ingredients, with the remainder being water, making it easier to handle and safer than disinfectants used to inactivate the novel coronavirus, such as alcohol disinfectants, aqueous sodium hypochlorite solutions, detergents, hypochlorous acid water, and chlorous acid water.
There is no particular limitation on the type of water.

The composition of the present invention contains the above-mentioned cypress oil, grapefruit seed extract, and vegetable oil-derived emulsifier as active ingredients, but any naturally derived ingredient may be used as long as it does not significantly impair the effects of the present invention.

The pH of the composition of the present invention is preferably adjusted to the range of 3.5 to 6.0, from the viewpoints of ease of handling and minimal effect on objects that come into contact with the composition of the present invention.

The composition of the present invention can be prepared by appropriately mixing the above-mentioned components. There are no particular limitations on the mixing means, mixing conditions, or order in which the components are mixed.

The composition of the present invention may be in an undiluted form or a diluted form. The undiluted form is used without dilution to inactivate the novel coronavirus to be treated. The diluted form is used to inactivate the novel coronavirus to be treated by diluting it with water at the recommended dilution concentration to a concentration of active ingredient that will be effective in inactivating the novel coronavirus.

The compositions of the present invention are used on hard surfaces of inanimate objects, textiles and fabrics where there is a concern of contamination with the novel coronavirus.
Examples of the hard surfaces include floors, walls, windows, doors, food processing equipment, medical equipment, various furniture, home appliances, instruments, tools, toys, etc. in homes and business facilities, such as restrooms, toilets, bathrooms, washrooms, shower stands, kitchens, living rooms, bedrooms, etc. Examples of materials for the hard surfaces include wood, bamboo, plastic (including silicone resins, etc.), metal, ceramic, glass, and combinations thereof.
Examples of the fibers and fiber products include clothing, towels, masks, sofas, curtains, carpets, bedding, cushions, shoes, and bags.

To inactivate the novel coronavirus, the composition of the present invention is brought into contact with the target to be treated. From the viewpoint of inactivating the novel coronavirus, the contact time is 10 seconds or longer, preferably 1 minute or longer, more preferably 5 minutes or longer, and even more preferably 10 minutes or longer.
The contacting means is not particularly limited, and examples thereof include coating, spraying, immersion, and the like.

The composition of the present invention is liquid and exhibits good dispersion and dissolution in water, which is the solvent for each active ingredient. Therefore, by filling it into a spray container, it can be easily sprayed onto the desired target. Specific product forms include air spray products.

The composition of the present invention can also be in the form of being applied to or impregnated into woven or nonwoven fabrics made of paper, natural fibers, recycled fibers (rayon, etc.) and/or synthetic fibers (polyethylene, polypropylene, polyester, etc.).
Specific product or formulation forms include wet wipes and the like.

The composition of the present invention is expected to prevent COVID-19 infection by inactivating the novel coronavirus attached to inanimate objects.
Furthermore, the composition of the present invention is made from naturally occurring ingredients and is therefore highly safe. It can be used for a wide range of materials in homes and business facilities, including hard surfaces such as floors, walls, windows, doors, food processing equipment, medical equipment, restrooms, toilets, bathrooms, washrooms, shower basins, kitchens, living rooms, bedrooms, and various other furniture, home appliances, instruments, tools, and toys, as well as textile products such as clothing, towels, masks, sofas, curtains, carpets, bedding, cushions, shoes, and bags. It can also be suitably used in items and living spaces used by young children, the elderly, and sick people.
Furthermore, since the composition of the present invention uses cypress oil, it not only disinfects and deodorizes objects and spaces treated with the composition of the present invention, but also allows users to relax with the scent of cypress by using the treated objects or being in the treated spaces.

The present invention will be explained in more detail below using examples, but the present invention is not limited to these examples in any way.

Example 1: Preparation of Composition A
Composition A (pH within the range of 4.0 to 6.0) was prepared by mixing the following ingredients: 0.66 wt% domestic cypress essential oil, 0.2 wt% grapefruit seed extract, 0.4 wt% plant-derived emulsifier (containing lauric acid as a constituent fatty acid in the emulsifier), and the remainder water (purified water).
The resulting composition A was an emulsified liquid and smelled of cypress.

(Example 2: Preparation of Composition B)
Composition A obtained in Example 1 was diluted 10 times with purified water to prepare composition B (pH in the range of 4.0 to 6.0).
The resulting composition B was in the form of an emulsified liquid, and although the cypress smell was weaker than that of composition A, it still had a cypress smell.

(Test Example 1: Acute inhalation toxicity test)
Composition A obtained in Example 1 was subjected to an acute inhalation toxicity test.
The test was conducted by the Drug Safety Testing Center, Yoshimi Research Institute (25-1 Kuroiwa, Yoshimi-machi, Hiki-gun, Saitama Prefecture).
A total of 10 test animals, 5 male and 5 female ICR mice (Slc: ICR, SPF, 5 weeks old at the time of administration), were used in the test.
The test method was whole-body exposure, and was carried out using an experimental tank of 0.5 ^m3 (H 120 cm x D 60 cm x W 70 cm) with reference to the method of Yamashita et al. (Poisoning Research, 8:225-233, 1995). Mice were housed in groups in wire mesh cages placed approximately in the center of the experimental tank. The exposure method consisted of 10 pushes per session, given every 5 minutes, for a total of 20 sessions. The amount sprayed per session was 2.8-3.2 g, for a total spray amount of 58.3 g. This is approximately 80 times the amount sprayed in actual use.

The general condition of the animals was observed from the start of exposure until 14 days after exposure, during which time the body weight and food intake were measured.
The weight of the animals was measured before and after feeding on days 1, 2, 3, 7, and 14 after the start of exposure, and the daily food intake per animal was calculated by dividing the weight by the number of animals.

As a result, no deaths were observed, and no abnormalities were noted in the animals' general condition. Although some individuals, both males and females, showed a decrease in body weight 1-2 days after exposure, they showed a steady increase from 2-3 days after exposure, and this was thought to be a temporary decrease due to the exposure procedure.

After 14 days of exposure, the animals were anesthetized by intraperitoneal administration of sodium pentobarbital and then sacrificed by exsanguination, and the appearance of the body surface, orifices, cranial cavity, thoracic cavity, abdominal visceral organs and lymph nodes was examined with the naked eye.
The lungs were fixed in 10% neutral phosphate buffered formalin, paraffin sections were prepared, stained with hematoxylin and eosin, and examined microscopically.

No changes in average food intake or autopsy were observed due to Composition A. In histopathological examination of the lungs, exudative hemorrhage was observed in one male, but this was localized fresh hemorrhage, and since there was only one case of occurrence, it was presumed to be an accidental change.
From the above results, no acute inhalation toxicity was observed for Composition A under the test conditions.

(Test Example 2: Deodorizing Effect Test)
Composition A obtained in Example 1 was subjected to a deodorizing effect test.
The test was conducted by the Japan Food Analysis Center (52-1 Motoyoyogi-cho, Shibuya-ku, Tokyo).
10 mL of composition A was placed in a smell bag (35 cm x 50 cm), heat-sealed, and then 9 L of air was sealed inside. Test gases (ammonia about 100 ppm, trimethylamine about 20 ppm, isovaleric acid about 15 ppm, formaldehyde about 40 ppm, acetic acid about 50 ppm, pyridine about 10 ppm) were added to achieve the set gas concentrations. This was left standing at room temperature, and the gas concentrations in the bag were measured using a gas detector tube every elapsed time (10 minutes, 30 minutes, 1, 3, and 6 hours). A blank test was also conducted using the same procedure without adding composition A.

As a result, compared to the blank test, composition A significantly reduced the concentrations of all of the test gases, namely ammonia, trimethylamine, isovaleric acid, formaldehyde, acetic acid and pyridine.
From the above results, it was found that Composition A had a deodorizing effect under the test conditions.

(Test Example 3: Disinfection Effect Test)
Composition A obtained in Example 1 was subjected to a disinfecting effect test.
The test was conducted by the Japan Food Analysis Center (52-1 Motoyoyogi-cho, Shibuya-ku, Tokyo).
0.1 mL of a test bacterial solution containing Escherichia coli or Staphylococcus aureus was inoculated into 10 mL of composition A, and the number of viable bacteria in the resulting test solution was measured at room temperature after predetermined times (1 minute, 5 minutes, and 15 minutes).
The viable cell count was measured using SCDLP agar medium (Nihon Pharmaceutical Co., Ltd.) by the pour plate culture method at 35°C ± 1°C for 2 days. Purified water was used as a control for E. coli, and physiological saline was used as a control for Staphylococcus aureus.
Furthermore, a preliminary test (to confirm the neutralization conditions) was conducted in advance to confirm the conditions under which the viable cell count could be measured without being affected by composition A.
The test bacterial solutions used were one consisting of Esherichia coli (NBRC3972) and water, and one consisting of Staphylococcus aureus subsp. aureus (NBRC12732) and water.
The bacterial concentration in each test bacterial solution was adjusted to 10 ⁷ to 10 ⁸ /mL.

The results obtained are shown in Table 1 below.

These results show that Composition A has a disinfecting effect that inhibits the growth of Escherichia coli and a bactericidal effect against Staphylococcus aureus.

(Test Example 4: Novel coronavirus inactivation effect test)
Composition A obtained in Example 1 and Composition B obtained in Example 2 were subjected to a test for their effectiveness in inactivating the novel coronavirus.
The test was conducted by the Department of Microbiology and Infectious Diseases, School of Medicine, Nara Medical University (840 Shijo-cho, Kashihara City, Nara Prefecture).

The test was carried out in the following procedure.

(Preparation of test viruses)
VeroE6 cells were infected with the test virus (novel coronavirus (SARS-CoV-2)), and those that showed a cytopathic effect were collected and stored frozen in a -80°C freezer. After two cycles of freezing and thawing, the cells were centrifuged, and the supernatant was concentrated and purified using an ultrafiltration membrane. This was used as the test virus solution, and was stored frozen in a -80°C freezer until testing.

(Exam contents)
The test product (Composition A or Composition B) was mixed in a ratio of 1 part virus to 9 parts.
The test sample was left to stand as shown in Table 2.
After the reaction time, the reaction was stopped by diluting with BSA-containing SCDLP medium, and the virus was collected.
The recovered solution was used to infect VeroE6 cells, and the viral infectivity titer was measured by the plaque assay.
After 3 days of culture, the cells were observed, and the viral infectivity and viral inactivation effect were calculated.

The inactivation effect was calculated as follows:
Inactivation effect (Mv) = log (C _t /C ₀ ) - log (N _t /N ₀ )
= log C _t /N _t
Ct : control infectious titer after t hours
C ₀ : Control infectious titer after 0 hours
_Nt : Infectivity of test item after t hours
N ₀ : Infectivity value of test sample after 0 hours

The reduction rate was calculated from the logarithmic reduction value according to the following formula (1).

All testing was conducted in a Biosafety Level 3 (BSL3) laboratory at Nara Medical University under appropriate pathogen containment equipment.

The results obtained are shown in Tables 3 and 4.

From the results in Tables 3 and 4, when Composition A and Composition B were contacted with the novel coronavirus (SARS-CoV-2) with an infectivity titer of 1.63 x 10 ⁷ PFU/ml, the infectivity titer decreased over time, and the infectivity titers after 10 minutes were 2.00 x 10 ⁵ PFU/ml (reduction rate 98.7%) and 8.75 x 10 ⁵ PFU/ml (reduction rate 94.6%), respectively.
Therefore, it was found that both Compositions A and B are effective in inactivating the new coronavirus (SARS-CoV-2).

Claims (4)

A novel coronavirus (SARS-CoV-2) inactivation composition containing, as active ingredients, cypress oil , grapefruit seed extract , and a vegetable oil-derived emulsifier containing lauric acid as a constituent fatty acid , and having a pH of 3.5 to 6.0 . The novel coronavirus (SARS-CoV-2) inactivating composition according to claim 1, comprising, as active ingredients, 0.066 to 10% by weight of cypress oil, 0.02 to 5% by weight of grapefruit seed extract, and 0.04 to 8% by weight of a vegetable oil-derived emulsifier containing lauric acid as a constituent fatty acid . 0.1 to 10% by weight of cypress oil,
Grapefruit seed extract 0.05 to 5% by weight,
The novel coronavirus (SARS-CoV-2) inactivating composition according to claim 1, comprising 0.1 to 8% by weight of a vegetable oil-derived emulsifier containing lauric acid as a constituent fatty acid , the remainder being water. The novel coronavirus (SARS-CoV-2) inactivating composition according to claim 1 or 2, wherein the cypress oil is cypress essential oil extracted from Japanese cypress.