JP7629693B2 - Antibacterial agents - Google Patents

Description

The present invention relates to an antibacterial agent that does not exhibit antibacterial activity against resident Staphylococcus aureus and exhibits selective antibacterial activity against target bacteria.

The human body is home to a community (bacterial flora) of symbiotic microorganisms known as resident bacteria, which act as a defense against the invasion of pathogens from the outside. However, when the body's resistance is weakened due to illness or psychological stress, the appropriate balance of the bacterial flora is disrupted, leading to the overgrowth of some resident bacteria and the invasion and proliferation of other pathogens, resulting in the development of various infectious disease symptoms.

Treatment of bacterial infections generally involves the use of antibacterial drugs that have antimicrobial growth inhibitory, bacteriostatic, or bactericidal effects. For example, various antibacterial drugs, such as penicillin-based antibacterial drugs, and antifungal drugs against mold, etc., are used.

Here, Staphylococcus aureus, a gram-positive coccus, is known as a common bacterium frequently detected on human skin, nasal cavity, etc. Like other common bacteria, Staphylococcus aureus can cause inflammation due to abnormal proliferation, but in a typical adult, it usually subsides with mild purulent symptoms or food poisoning symptoms, and rarely causes serious infections.

On the other hand, in people with low resistance and physical strength, such as the elderly, hospitalized patients, and those with illnesses, the abnormal proliferation of Staphylococcus aureus is prone to causing symptoms such as fever and diarrhea, as well as inflammation that can become severe, leading to severe infections such as pneumonia, sepsis, infective endocarditis, osteomyelitis, peritonitis, and meningitis. In such cases, the use of appropriate antibiotics against Staphylococcus aureus can prevent or treat further aggravation.

Here, Staphylococcus aureus has the property of easily acquiring resistance to antibiotics. For this reason, even if the symptoms of an infection can be improved by administering an antibiotic, Staphylococcus aureus may take advantage of the exposure to an environment that is difficult for the antibiotic to grow in and acquire resistance. Once Staphylococcus aureus has acquired such antibiotic resistance, if an infection occurs later due to its abnormal proliferation, antibiotics will no longer be effective, making treatment difficult.

A typical example of Staphylococcus aureus that has acquired resistance to antibiotics is methicillin-resistant Staphylococcus aureus. This resistant bacterium was discovered as Staphylococcus aureus that was resistant to methicillin, but in fact it is known to have acquired resistance to many antibiotics, not just methicillin. Methicillin-resistant Staphylococcus aureus is likely to appear in hospitals where antibiotics are frequently used, and is known to be the causative agent of mass infections.

On the other hand, some herbal medicines and Kampo medicines have been reported to have antibacterial properties. For example, it has been reported that Shini-seihai-to has a growth inhibitory effect against gram-positive bacteria, Streptococcus pneumoniae (Non-Patent Document 1). In addition, Shini-seihai-to has been confirmed to have a strong growth inhibitory effect against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus, and its usefulness as a treatment for infections caused by these bacteria has been reported (Non-Patent Documents 2 and 3). In addition, it has been reported that Sho-seiryu-to has an antibacterial effect against Staphylococcus aureus (Non-Patent Document 4).

Pharmacogenet. J., 8, 20-23(2016). Traditional & Kampo Medicine, 4(2), 111-115(2017). Proceedings of the 33rd Annual Meeting of the Japanese Society of Traditional Chinese Medicine, p. 61 Nikki Eclipse Bulletin, 48(5), 401-407(1997)

In order to effectively prevent the development of antibacterial resistance in Staphylococcus aureus, it is essential not to expose Staphylococcus aureus to an environment that is difficult for it to grow in, even when antibacterial agents are being used, in which case it may acquire antibacterial resistance. In other words, it is essential to exert the necessary antibacterial effect on the target bacteria, while at the same time not exerting an antibacterial effect on normally resident Staphylococcus aureus so that it does not acquire antibacterial resistance; in other words, selective antibacterial action is essential.

In this regard, Shini-seihai-to has antibacterial properties against Streptococcus pneumoniae and is therefore useful as an antibacterial agent targeting Streptococcus pneumoniae, but considering that it also has strong antibacterial properties against Staphylococcus aureus, it cannot be used for selective antibacterial purposes.

The present invention aims to provide an antibacterial agent that does not exhibit antibacterial activity against normally resident Staphylococcus aureus and exhibits selective antibacterial activity against target bacteria.

After extensive research, the inventors have found that the use of a specific herbal extract containing Shini-seihai-to in a specific low dose enables selective antibacterial activity that exhibits the necessary antibacterial activity against the target bacteria while at the same time not exhibiting antibacterial activity against Staphylococcus aureus. The present invention was completed based on this finding and through further research.

That is, the present invention provides the following aspects.
Item 1. A Chinese herbal medicine extract selected from the group consisting of Shini-seihai-to, Keigaku-renkyo-to, Kakkonto-ka-senkyu-shini, and Sho-seiryu-to,
The dose of the extract in terms of the original herbal medicine is 21 g/day or less for Shini-sei-hai-to, 21.38 g/day or less for Kei-kei-ren-kyo-to, 18 g/day or less for Kakkon-to-ka-sen-kyu-shini, and 20.3 g/day or less for Sho-sei-ryu-to; and
An antibacterial agent that does not target resident Staphylococcus aureus.
Item 2. The antibacterial agent according to Item 1, which is applied to a subject who has taken an antibacterial agent having antibacterial activity against Staphylococcus aureus within the past year.
Item 3. The antibacterial agent according to Item 1 or 2, which is used against upper respiratory tract infections and inflammation caused thereby.
Item 4. The antibacterial agent according to Item 1 or 2, which is used against oral infections, skin infections, and lower respiratory tract infections, and inflammation caused by these infections.
Item 5. The antibacterial agent according to any one of Items 1 to 4, which targets bacteria selected from the group consisting of Streptococcus mutans, Porphyromonas gingivalis, Fusobacterium, Clostridium sobrinus, and Propionibacterium acnes.

According to the present invention, an antibacterial agent is provided that does not exhibit antibacterial activity against normally resident Staphylococcus aureus and exhibits selective antibacterial activity against target bacteria. This is expected to suppress the acquisition of antibacterial resistance by Staphylococcus aureus.

The antibacterial agent of the present invention contains an extract of a herbal medicine selected from the group consisting of Shini-seihai-to, Keigaku-renkyo-to, Kakkonto-ka-senkyu-shini, and Sho-seiryu-to, is used at a prescribed dose, and is characterized in that it does not target Staphylococcus aureus.

The active ingredient Shini Seifei Tang is preferably a herbal prescription described in "New Guide to General Kampo Prescriptions" (Edited by Goda Yukihiro and Hakamzuka Takashi, edited by the Japan Kampo Herbal Medicine Preparations Association, published by Jiho Co., Ltd.) or "Standards for Approval of the Manufacturing and Sale of General Kampo Preparations (Attachment)" (Pharmaceutical and Food Safety Bureau, Ministry of Health, Labour and Welfare, April 1, 2017), and examples of such prescriptions include a mixture of herbal medicines consisting of Shin I, Zhimo, Byakugo, Scutellaria, Sanshishi, Bakumondou, Sekko, Citrus Rhizome, and Biwayo.

As a more specific example of the mixed herbal medicines that make up Shini Seifei Tang, the weight mixing ratio of Shini, Chimo, Byakugo, Scutellaria Root, Sanshishi, Bakumondou, Sekko, Citrus Amaranth, and Biwayo is, for example, 2.0 to 3.0 parts by weight of Shini, 3.0 parts by weight of Chimo, 3.0 parts by weight of Byakugo, 3.0 parts by weight of Scutellaria Root, 1.5 to 3.0 parts by weight of Sanshishi, 5.0 to 6.0 parts by weight of Sekko, 5.0 to 6.0 parts by weight, 1.0 to 1.5 parts by weight, and 1.0 to 3.0 parts by weight of elm. Examples include those with 3.0 parts by weight of scutellaria, 3.0 parts by weight of thyme, 3.0 parts by weight of white gourd, 3.0 parts by weight of scutellaria, 1.5 parts by weight of Chinese quince, 6.0 parts by weight of gypsum, 6.0 parts by weight of gypsum, 1.5 parts by weight of elm, and 1.0 part by weight of elm.

As for Keikakurenkyoto, the Kampo prescription described in "New Guide to General Kampo Prescriptions" (Edited by Goda Yukihiro and Hakamzuka Takashi, Edited by the Japan Kampo Herbal Medicine Preparations Association, Published by Jiho Co., Ltd.) or "Standards for Approval of Manufacturing and Sales of General Kampo Preparations (Attachment)" (Pharmaceutical and Food Safety Bureau, Ministry of Health, Labour and Welfare, April 1, 2017) is preferable, and includes a mixture of herbs consisting of Angelica Root, Peony Root, Cnidium Root, Rehmannia Root, Coptis Root, Scutellaria Root, Phellodendron Bark, Sanshishi, Forsythia Root, Celastrus Root, Boufu Root, Mentha Root, Phellinus Root, Licorice Root, Bupleurum Root, Angelica Root, and Platycodon Root. Some letters do not include Rehmannia Root, Coptis Root, Phellodendron Bark, and/or Mint.

As a more specific example of the mixed herbal medicines that make up Keigaku Forsythia Tang, the weight ratios of Angelica Root, Peony Root, Cnidium Root, Rehmannia Root, Coptis Root, Scutellaria Root, Phellodendron Bark, Sanshishi Root, Forsythia Root, Sirolimus Root, Bougainvillea Root, Mentha Root, Phellodendron Root, Licorice Root, Bupleurum Root, White Flower Root, and Platycodon Root are as follows: Angelica Root 1.5 parts by weight, Peony Root 1.5 parts by weight, Cnidium Root 1.5 parts by weight, Rehmannia Root 1.5 parts by weight, Coptis Root 1.5 parts by weight, Scutellaria Root 1.5 parts by weight, Phellodendron Root 1.5 parts by weight, Bougainvillea Root 1.5 parts by weight, Mentha Root 1.5 parts by weight, Phellodendron Root 1.5 parts by weight, Licorice Root 1. 0-1.5 parts by weight, 1.5-2.5 parts by weight of Bupleurum Root, 1.5-2.5 parts by weight of Angelica Root, 1.5-2.5 parts by weight of Angelica Root, 1.5-2.5 parts by weight of Platycodon Root, and preferably 1.5 parts by weight of Angelica Root, 1.5 parts by weight of Peony Root, 1.5 parts by weight of Cnidium Root, 1.5 parts by weight of Rehmannia Root, 1.5 parts by weight of Coptis Rhizome, 1.5 parts by weight of Scutellaria Root, 1.5 parts by weight of Phellodendron Bark, 1.5 parts by weight of Sanshi Fruit, 1.5 parts by weight of Forsythia Root, 1.5 parts by weight of Japanese Pear, 1.5 parts by weight of Japanese Pepper, 1.5 parts by weight of Saussurea Root, 1.5 parts by weight of Phellodendron Root, 1.5 parts by weight of Mentha Root, 1.5 parts by weight of Phellodendron Root, 1.5 parts by weight of Licorice Root, 2.5 parts by weight of Bupleurum Root, 2.5 parts by weight of Angelica Root, and 2.5 parts by weight of Platycodon Root.

For Kakkonto-ka-senkyu-shini, the Kampo prescriptions described in the "New Guide to General Kampo Prescriptions" (Edited by Goda Yukihiro and Hakamzuka Takashi, edited by the Japan Kampo Herbal Medicine Preparations Association, published by Jiho Co., Ltd.) or the "Standards for Approval of the Manufacture and Sale of General Kampo Preparations (Attachment)" (Pharmaceutical and Food Safety Bureau, Ministry of Health, Labour and Welfare, April 1, 2017) are preferred, and include mixed herbs consisting of Kakkon, Ephedra, Taisou, Cinnamon, Peony Root, Licorice, Shokyo, Cnidium, and Shini.

As a more specific example of the mixed herbal medicines that make up Kakkonto-ka-senkyu-shini, the weight ratio of Kakkon, Ephedra, Taiso, Cinnamon, Peony, Licorice, Ginger, Cnidium, and Shini is as follows: Kakkon 4.0-8.0 parts by weight, Ephedra 3.0-4.0 parts by weight, Taiso 3.0-4.0 parts by weight, Cinnamon 2.0-3.0 parts by weight, Peony 2.0-3.0 parts by weight, Licorice 2.0 parts by weight, Sho Examples include those containing 1.0 to 1.5 parts by weight of Ukyou, 2.0 to 3.0 parts by weight of Cnidium Root, and 2.0 to 3.0 parts by weight of Xanthomonas Root, and preferably those containing 4.0 parts by weight of Pueraria Root, 4.0 parts by weight of Ephedra Root, 3.0 parts by weight of Taisou Root, 2.0 parts by weight of Cinnamon Bark, 2.0 parts by weight of Peony Root, 2.0 parts by weight of Licorice Root, 1.0 part by weight of Zingiber Root, 3.0 parts by weight of Cnidium Root, and 3.0 parts by weight of Xanthomonas Root.

As Shoseiryuto, the Kampo prescription described in "New Guide to General Kampo Prescriptions" (Edited by Goda Yukihiro and Hakamzuka Takashi, Edited by the Japan Kampo Herbal Medicine Preparations Association, Published by Jiho Co., Ltd.) or "Standards for Approval of Manufacturing and Sales of General Kampo Preparations (Attachment)" (Pharmaceutical and Food Safety Bureau, Ministry of Health, Labor and Welfare, April 1, 2017) is preferable, and examples of the herbal medicine mixture include Ephedra, Peony Root, Kankyo, Glycyrrhiza Root, Cinnamon Bark, Saishin, Gomishi, and Pinellia Root.

More specific examples of the mixed herbal medicines that make up Shoseiryuto include 2.0-3.5 parts by weight of Ephedra, 2.0-3.5 parts by weight of Peony Root, 2.0-3.5 parts by weight of Kankyo, 2.0-3.5 parts by weight of Licorice, 2.0-3.5 parts by weight of Cinnamon Bark, 2.0-3.5 parts by weight of Saishin, 1.0-3.0 parts by weight of Gomizushi, and 3.0-8.0 parts by weight of Pinellia Sinensis, and preferably 3.0 parts by weight of Ephedra, 3.0 parts by weight of Peony Root, 3.0 parts by weight of Kankyo, 3.0 parts by weight of Licorice, 3.0 parts by weight of Cinnamon Bark, 3.0 parts by weight of Saishin, 3.0 parts by weight of Gomizushi, and 6.0 parts by weight of Pinellia Sinensis.

The extract of Shini-sei-hai-to, the extract of Kei-kei-ren-kyo-to, the extract of Kakkon-to-ka-sen-kyu-shini-to, and the extract of Sho-sei-ryu-to can be obtained by extracting the above-mentioned mixed herbal medicines and concentrating the resulting extract as necessary, or by drying the extract to obtain an extract powder.

In the production of Shini-sei-hai-to extract, Kei-kei-ren-kyo-to extract, Kakkon-to-ka-sen-kyu-shini extract, and Sho-sei-ryu-to extract, the extraction solvent used in the extraction process is not particularly limited, but examples include water or aqueous ethanol, preferably water. The drying process is also not particularly limited, and includes known methods such as the spray drying method and a method in which a suitable adsorbent (e.g., silicic anhydride, starch, etc.) is added to a soft extract with a high concentration of the extract liquid to obtain an adsorbed powder.

The extracts of Shin'i-seihai-to, Keigaku-renkyo-to, Kakkonto-ka-senkyu-shin'i, and Sho-seiryu-to used in the present invention may be extracts prepared by the above-mentioned methods or commercially available extracts.

In the antibacterial agent of the present invention, the above-mentioned herbal extracts may be used alone or in combination of two or more.

In the antibacterial agent of the present invention, the content of the herbal extract selected from the group consisting of Shini-seihai-to, Kei-kei-ren-kyo-to, Kakkon-to-ka-sen-kyu-shini, and Sho-sei-ryu-to is not particularly limited as long as it exerts the effects of the present invention, but may be, for example, 1 to 100% by weight in terms of the amount of dried extract. When a dried extract (extract powder) is used, the content is the amount itself, and when an extract liquid or soft extract is used, the content is the amount converted into the amount remaining after removing the solvent. In addition, when the dried extract powder contains additives such as adsorbents added during production, the content is the amount excluding the additives.

Other components The antibacterial agent of the present invention may contain other pharmacological components, if necessary, in addition to the above-mentioned herbal medicine. The types of such pharmacological components are not particularly limited, but examples thereof include antacids, stomachics, digestive agents, intestinal regulators, antispasmodics, mucosal repair agents, anti-inflammatory agents, astringents, antiemetics, antitussives, expectorants, anti-inflammatory enzymes, sedatives, hypnotics, antihistamines, caffeine, cardiac diuretics, antibacterial agents (other than the above-mentioned active ingredients), vasoconstrictors, vasodilators, local anesthetics, herbal medicines, herbal extracts (other than the above-mentioned active ingredients), vitamins, and menthols. These pharmacological components may be used alone or in combination of two or more. The content of these pharmacological components may be appropriately set from known ones according to the type of pharmacological component to be used.

The antibacterial agent of the present invention may contain pharma- ceutically acceptable bases and additives, etc., as necessary, in order to prepare the agent into a desired dosage form. Examples of such bases and additives include excipients, binders, disintegrants, lubricants, isotonicity agents, plasticizers, dispersants, emulsifiers, solubilizers, wetting agents, stabilizers, suspending agents, adhesives, coating agents, glossing agents, water, oils and fats, waxes, hydrocarbons, fatty acids, higher alcohols, esters, water-soluble polymers, surfactants, metal soaps, lower alcohols, polyhydric alcohols, pH adjusters, buffers, antioxidants, UV inhibitors, preservatives, flavorings, fragrances, powders, thickeners, dyes, chelating agents, etc. These bases and additives may be used alone or in combination of two or more. The content of these bases and additives may be appropriately set from known ones according to the type of additive component used and the dosage form, etc.

Dosage form The dosage form of the antibacterial agent of the present invention is not particularly limited, and may be any of tablets, granules, powders, pills, capsules, films, liquids (drinks, mouthwashes), etc. Among these dosage forms, in the case of internal use, tablets and granules are preferred from the viewpoint of ease of administration, and in the case of external use, mouthwash is preferred from the viewpoint of ease of application. These dosage forms can be prepared using pharma- ceutically acceptable base materials and additives, and the types and amounts of the base materials and additives are also known in the field of formulation technology.

Uses The antibacterial agent of the present invention does not exhibit antibacterial activity against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus, and is therefore used for the purpose of selective antibacterial activity that does not target resident Staphylococcus aureus while exerting antibacterial activity against target bacteria. Resident state refers to a state in which resident bacteria are not abnormally proliferating, and resident Staphylococcus aureus refers to Staphylococcus aureus in a state in which it is not abnormally proliferating to the extent that it does not cause a Staphylococcus aureus infection. Preferably, the antibacterial agent of the present invention is used for the purpose of selective antibacterial activity that does not target resident Staphylococcus aureus and resident methicillin-resistant Staphylococcus aureus while exerting antibacterial activity against target bacteria.

The target bacteria are not particularly limited as long as they are bacteria that cause bacterial infections and inflammations caused by them. Examples of bacterial infections and inflammations caused by them include upper respiratory tract infections, oral infections, skin infections, circulatory system infections, and/or lower respiratory tract infections, and/or inflammations caused by them. Examples of oral infections and inflammations caused by them include periodontal disease, gingivitis, dental caries, etc.; examples of upper respiratory tract infections and inflammations caused by them include otorhinolaryngeal infections (sinusitis, rhinitis, nasal vestibular eczema, otitis media, etc.), tonsillitis, epiglottitis, pharyngitis, etc.; examples of skin infections and inflammations caused by them include eczema, acne vulgaris, etc.; examples of circulatory system infections and inflammations caused by them include sepsis, etc.; examples of lower respiratory tract infections and inflammations caused by them include bronchitis, bacterial pneumonia, etc., and preferably include upper respiratory tract infections, oral infections, skin infections, lower respiratory tract infections, and inflammations caused by them.

Examples of bacteria include gram-positive bacteria and gram-negative bacteria. Specific examples of bacteria include Streptococcus mutans, Porphyromonas gingivalis, Fusobacterium nucleatum, Streptococcus sobrinus, Streptococcus pneumoniae, Haemophilus influenzae, and Propionibacterium acnes.

The antibacterial agent of the present invention can be used to improve the abnormal proliferation of the above bacteria.

For example, when the antibacterial agent of the present invention is administered internally, it can be used, more specifically, for the purpose of improving (treating or inhibiting the progression of) the above-mentioned bacterial infections and inflammation caused thereby. In other words, the antibacterial agent of the present invention can be applied to patients who have developed the above-mentioned bacterial infections and inflammation caused thereby. In this way, patients who have developed bacterial infections and inflammation caused thereby have a weakened immune system and are already in a state where the causative bacteria are abnormally proliferating, so it is no longer possible to eliminate the bacteria through symptomatic treatment such as boosting the immune system, and the symptoms cannot be effectively improved. Since the antibacterial agent of the present invention is an antibacterial agent that directly exhibits an antibacterial effect against the causative bacteria, it is expected that the symptoms of the above-mentioned patients will be effectively improved.

In addition, when the antibacterial agent of the present invention is applied externally (particularly in and outside the oral cavity), it can be used, more specifically, for the purpose of improving abnormal proliferation caused by the above-mentioned bacteria (particularly bacteria causing oral infections).

The antibacterial agent of the present invention does not exhibit antibacterial activity against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus, and is therefore particularly useful when applied to subjects at high risk of developing drug resistance in Staphylococcus aureus. Specific examples of subjects at high risk of developing drug resistance in Staphylococcus aureus include subjects who have taken an antibacterial agent with antibacterial activity against Staphylococcus aureus within the past year. Antibacterial agents with antibacterial activity against Staphylococcus aureus include not only antibacterial agents that target Staphylococcus aureus, but also antibacterial agents that target bacteria other than Staphylococcus aureus and inevitably exhibit antibacterial activity against the non-target bacteria Staphylococcus aureus. Examples of such antibacterial agents include penicillin, cephalosporin, carbapenem, glycopeptide, oxazolidinone, lipopeptide, aminoglycoside, tetracycline, lincomycin, and/or rifamycin antibacterial agents.

Dosage and Method of Use The method of administration of the antibacterial agent of the present invention is not particularly limited, but preferred methods include oral administration (internal use) and intraoral administration (external use).

The dosage of the antibacterial agent of the present invention is, in terms of the amount of the original herbal medicine, 21 g/day or less for Shini-seihai-to extract, 21.38 g/day or less for Keigaku-renkyo-to extract, 18 g/day or less for Kakkonto-ka-senkyu-shini extract, and 20.3 g/day or less for Sho-seiryu-to extract, in order to exert a selective antibacterial effect. The lower limit of the range of the dosage in terms of the original herbal medicine may be appropriately determined by a person skilled in the art within the range in which antibacterial activity is exerted, for example, 8.4 g/day or more, preferably 14 g/day or more for Shini-seihai-to extract, 14.2 g/day or more for Keigaku-renkyo-to extract, 12 g/day or more for Kakkonto-ka-senkyu-shini extract, and 8.1 g/day or more for Sho-seiryu-to extract.

The dosage of the antibacterial agent of the present invention may be an amount equivalent to 2.25 g/day or less of the original herbal drug of Zhimo when Shini-sei-fei-to extract is used as the active ingredient of the antibacterial agent of the present invention; an amount equivalent to 1.13 g/day or less of the original herbal drug of Touki when Kei-gaku-ren-kyo-to extract is used as the active ingredient of the antibacterial agent of the present invention, in order to exert a selective antibacterial effect; an amount equivalent to 1.5 g/day or less of the original herbal drug of Licorice when Kakkonto-ka-senkyu-shini extract is used as the active ingredient of the antibacterial agent of the present invention. The lower limit of the range of the amount of each of the herbal medicines in terms of the original herbal medicine may be appropriately determined by a person skilled in the art within the range in which the antibacterial agent of the present invention exhibits antibacterial activity. For example, when Shini-sei-fei-to extract is used as the active ingredient of the antibacterial agent of the present invention, an amount equivalent to 0.9 g/day or more of Zhimo in terms of the original herbal medicine may be used; when Kei-gaku-ren-kyo-to extract is used as the active ingredient of the antibacterial agent of the present invention, an amount equivalent to 0.75 g/day or more of Touki in terms of the original herbal medicine may be used; when Kakkon-to-ka-sen-kyu-shin-i extract is used as the active ingredient of the antibacterial agent of the present invention, an amount equivalent to 1 g/day or more of Licorice in terms of the original herbal medicine may be used.

The dosage of the antibacterial agent of the present invention may be, in terms of the amount of dry extract, 3.38 g/day or less for Shini-seihai-to extract, 3.38 g/day or less for Keigaku-renkyo-to extract, 3 g/day or less for Kakkonto-ka-senkyu-shini extract, and 3.38 g/day or less for Sho-seiryu-to extract, in order to exert a selective antibacterial effect. The lower limit of the range of the dosage in terms of the amount of dry extract may be appropriately determined by a person skilled in the art within the range in which antibacterial properties are exerted, and examples thereof include 1.35 g/day or more, preferably 2.25 g/day or more for Shini-seihai-to extract, 2.25 g/day or more for Keigaku-renkyo-to extract, 2 g/day or more for Kakkonto-ka-senkyu-shini extract, and 1.35 g/day or more for Sho-seiryu-to extract.

The above dosages indicate the dosage per adult, more specifically, the dosage per 50 kg body weight.

The timing of administration of the antibacterial agent of the present invention is not particularly limited, and may be after waking up, before or after meals, between meals, or before going to bed. In the case of internal use, it is preferably before or between meals, and in the case of external use (particularly for oral use), it is preferably after waking up, after meals, between meals, and/or before going to bed. It is also preferable to administer the agent three times a day, and the dose calculated on a dry extract basis is 2.5 g/day or less for Shini-sei-hai-to extract, preferably 2.25 g/day or less for Kei-gaku-ren-kyo-to extract, 2.25 g/day or less for Kakkon-to-ka-sen-kyu-shini extract, and 2.25 g/day or less for Sho-sei-ryu-to extract; the dose calculated on a raw herbal medicine basis is 14 g/day or less for Shini-sei-hai-to extract, 1 g/day or less for Kei-gaku-ren-kyo-to extract, and 1 g/day or less for Sho-sei-ryu-to extract. 4.25 g/day or less, Kakkonto-ka-Senkyu-Shin'i extract 12 g/day or less, and Shoseiryu-to extract 13.5 g/day or less; Shini-seihai-to extract with a raw herbal equivalent of 1.5 g/day or less, Gekkei-renkyo-to extract with a raw herbal equivalent of 0.75 g/day or less, and Kakkonto-ka-Senkyu-Shin'i extract with a raw herbal equivalent of 1 g/day or less, may be administered twice a day (for example, twice a day in the morning and evening). Furthermore, in order to obtain the antibacterial effect of the present invention more effectively, it is preferable to administer continuously for 5 days or more, preferably 1 week or more, and more preferably 2 weeks or more. Furthermore, in order to obtain the selective antibacterial effect more effectively, the continuous administration period is preferably 4 weeks or less.

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

[Test Example 1]
1. Preparation of antibacterial agent
1-1. Shinseihaito extract
A mixture of herbs with the composition shown in Table 1 was prepared, and 10 times the amount of water by weight was added, followed by extraction with stirring at about 100°C for 1 hour. The extract was then collected by centrifugation, concentrated under reduced pressure, and dried using a spray dryer to obtain 4.5 g of Shini-seihai-to extract (equivalent to the full prescribed amount). This Shini-seihai-to extract was used as an antibacterial agent targeting pneumococcus.

1-2. Keigakurenkyoto Extract A mixture of herbs with the composition shown in Table 1 was prepared, and 20 times the amount of water by weight was added, followed by extraction with stirring at about 100°C for 1 hour. The extract was then collected by centrifugation, concentrated under reduced pressure, and dried using a spray dryer to obtain 4.5 g of Keigakurenkyoto extract (equivalent to the full prescribed amount). This Keigakurenkyoto extract was used as an antibacterial agent targeting Streptococcus pneumoniae.

1-3. Kakkonto-ka-Senkyu-Shin'i Extract A mixture of herbs with the composition shown in Table 1 was prepared, and 20 times the amount of water by weight was added, and extraction was performed with stirring at about 100°C for 1 hour. The extract was then collected by centrifugation, concentrated under reduced pressure, and dried using a spray dryer to obtain 4.0 g of Kakkonto-ka-Senkyu-Shin'i Extract (equivalent to the full prescribed amount). This Kakkonto-ka-Senkyu-Shin'i Extract was used as an antibacterial agent targeting pneumococcus.

1-4. Sho-seiryu-to extract A mixture of herbs with the composition shown in Table 1 was prepared, and 10 times the amount of water by weight was added, followed by extraction with stirring at about 100°C for 1 hour. The extract was then collected by centrifugation, concentrated under reduced pressure, and dried using a spray dryer to obtain 4.0 g of Shini-seihai-to extract (equivalent to the full prescribed amount). This Sho-seiryu-to extract was used as an antibacterial agent targeting Streptococcus pneumoniae.

2. Antibacterial Test In order to evaluate the inhibitory effect against bacterial proliferation on the skin and mucous membranes, an antibacterial test was carried out using an agar medium as follows.

1 mL of a bacterial solution containing 1 x ^106-107 CFU/mL of bacteria (Staphylococcus aureus, Staphylococcus methicillinii, Streptococcus pneumoniae) was added to a sterile petri dish with an inner diameter of 90 mm ^, and 15 g of nutrient agar medium heated to 45°C was added thereto and mixed thoroughly, then the mixture was left at room temperature to allow the excess water to evaporate and the agar to solidify. Next, a sterile filter paper with a diameter of 12 mm that had been impregnated with the extract in the amount shown in "Amount added to filter paper" in Tables 2-5 and dried was placed in the center of the petri dish and cultured for 24-48 hours.

The "amount added to filter paper" shown in Tables 2 to 5 was derived as the amount of extract exposed to the skin and mucosal tissues when the extract was taken at the "dosage" shown in Tables 2 to 5, based on the following: In other words, the antibacterial effect confirmed by the "amount added to filter paper" shown in Tables 2 to 5 indicates the antibacterial effect that is expressed in the body when the extract is taken at the "dosage" shown in Tables 2 to 5.

For example, the full dose of Shini-seihai-to extract (equivalent to dry extract) is 4.5 g/day, which is usually administered in three separate doses per day. Meanwhile, the blood volume of a human is 1/13 of the body weight, which is about 4 L for a 50 kg adult. In other words, when Shini-seihai-to extract is administered in three separate doses per day, the blood concentration of the extract at each dose is about 0.38 mg/mL (= 1.5 g/4 L). Here, the blood flow rate per 1 g of nasal mucosa tissue is about 1.2 mL/min (Otorhinolaryngology and Clinical Medicine, Vol. 37, p. 1180-1186, 1991), so the blood flow rate per 15 g of tissue is about 18 mL/min. Since there is no significant difference in blood flow rate between the skin and mucosa tissues, when a full dose of Shini-seihai-to extract is administered in one dose, 6.8 mg of extract (= 0.38 mg x 18 mL) is exposed per minute per 15 g of tissue. Therefore, in the case of Shini-seihai-to extract, the amount added to 15 g of agar medium (amount added to filter paper) per dose of 4.5 g/day was 6.8 mg (Comparative Example 1). In addition, the amount added was 5.1 mg (Example 1) as the amount equivalent to 75% of the full dose prescription, 3.4 mg (Example 2) as the amount equivalent to 50% of the full dose prescription, and 2.0 mg (Example 3) as the amount equivalent to 30% of the full dose prescription. The amounts added to filter paper were determined in the same manner for Keigakurenkyoto extract (full dose prescription (dry extract equivalent) is 4.5 g), Kakkonto-ka-senkyu-shini extract (full dose prescription (dry extract equivalent) is 4.0 g), and Sho-seiryu-to extract (full dose prescription (dry extract equivalent) is 4.0 g).

As a result of the cultivation, the width of the halo (inhibition zone) formed around the filter paper was calculated using the formula below, and the antibacterial activity of the extract against each bacterium was evaluated based on the evaluation criteria below. The results are shown in Tables 2 to 5.

(Evaluation criteria for antibacterial activity)
-: No halo
+: Halo width is 1-2mm
++: Halo width is 3-4mm
+++: Halo width is 5-6mm

As is clear from Tables 2 to 5, Shini-seihai-to, Keigairengyo-to, Kakkonto-ka-senkyu-shini, and Sho-seiryu-to were found to act as antibacterial agents against pneumococcus. Among these, Shini-seihai-to, Keigairengyo-to, Kakkonto-ka-senkyu-shini, and Sho-seiryu-to (Comparative Examples 1 to 4) at full doses all exhibited antibacterial effects not only against the target bacterium Streptococcus pneumoniae, but also against non-target bacteria Staphylococcus aureus and methicillin-resistant Staphylococcus aureus. In other words, when these herbal extracts are used as antibacterial agents, full dose prescriptions pose the risk of Staphylococcus aureus and methicillin-resistant Staphylococcus aureus acquiring antibiotic resistance. On the other hand, Shini-seihai-to, Keigaku-renkyo-to, Kakkonto-ka-senkyu-shini, and Sho-seiryu-to (Examples 1 to 10), all prescribed in doses less than the full dose prescription, exhibited antibacterial effects against the target bacteria Streptococcus pneumoniae, but did not exhibit antibacterial effects against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus, which are not target bacteria.

Test Example 2
Eleven sinusitis patients (men and women in their 20s to 40s) who had taken two or more antibiotics with antibacterial activity against Staphylococcus aureus (penicillins, cephalosporins, carbapenems, glycopeptides, oxazolidinones, lipopeptides, aminoglycosides, tetracyclines, lincomycins, and rifamycins) within the past year were selected as subjects with a high risk of developing drug resistance to Staphylococcus aureus. These subjects were given Shini-seihai-to extract prepared from the herbal mixture shown in Test Example 1 at a dose of 2.25 g/day in terms of dried extract (14 g/day in terms of raw herbal medicine, 1.5 g/day in terms of raw herbal medicine) three times a day for seven days. After seven days, the subjects were asked to answer questions about changes in the viscosity and/or color of purulent nasal discharge, and changes in symptoms of nasal congestion and/or shortness of breath.

Purulent rhinorrhea indicates that the mucous membrane is infected with bacteria, and a decrease in viscosity and lighter color of purulent rhinorrhea indicates that bacterial growth is suppressed. As a result of taking Shini-seihai-to extract, a decrease in viscosity and/or lighter color of purulent rhinorrhea was confirmed in 7 out of 11 subjects. In addition, 8 out of 11 subjects experienced improvement in nasal congestion, and 7 out of 11 subjects experienced improvement in shortness of breath. Furthermore, 10 out of 11 subjects responded that at least one of the following was observed: a decrease in viscosity and/or lighter color of purulent rhinorrhea, improvement in nasal congestion, and improvement in shortness of breath.

Test Example 3
Three adult males were administered the Shini-seihai-to extract prepared in Test Example 1 at a dose of 2.25 g/day in terms of dry extract (14 g/day in terms of raw herbal medicine, 1.5 g/day in terms of raw herbal medicine) three times a day for three days. Before and after administration, the nasal cavity was swabbed with a sterile cotton swab, and DNA was extracted from the bacteria attached to the cotton swab using a QIAamp DNA Mini Kit (Qiagen). Then, Amplicon PCR was performed using an Ion 16S Metagenomics Kit (Thermo Fisher), and the next-generation sequencing of the 18srRNA region was used to identify the bacterial species and calculate the number of bacteria that appeared (the relative number of bacteria after administration when the number of bacteria before administration was set to 100). The results are shown in Table 6.

As is clear from Table 6, there was no change in the number of Staphylococcus aureus bacteria before and after taking the drug, whereas a clear decrease in the number of Streptococcus pneumoniae, Haemophilus influenzae, Streptococcus mutans, Clostridium sobrinus, Fusobacterium spp., and Propionibacterium acnes bacteria was observed in all three subjects. This confirmed that Shini-seihai-to extract has selective antibacterial properties that do not target normally resident Staphylococcus aureus.

Test Example 4
Stickiness in the oral cavity is caused by abnormal proliferation of oral bacteria such as periodontal disease bacteria and dental caries bacteria in saliva, and causes bad breath and discomfort, as well as oral infections such as periodontal disease, gingivitis, and tooth decay, or inflammation due to these. Therefore, eight subjects (men and women in their 20s and 30s) who were concerned about stickiness in the oral cavity were asked to rinse their mouths with 50 mL of tap water after breakfast and with half the amount of the Shini-seihai-to extract prepared in Test Example 1, dissolved in 100 mL of tap water at 2.25 g (14 g in terms of raw herbal medicine, 1.5 g in terms of raw herbal medicine) in 2.25 g in terms of dried extract, after lunch. The strength of stickiness in the oral cavity, the strength of bad breath, and the pleasantness/unpleasantness in the oral cavity were evaluated after 4 hours. The strength of the bad breath was evaluated by the same third party on a nine-point scale from -4 to 4, and the strength of stickiness and pleasantness/unpleasantness were evaluated by the subject himself on a nine-point scale from -4 to 4. The scores ranged from -4 to 4, with 0 being "neither good nor bad," and the higher the score, the greater the stickiness in the oral cavity, the stronger the bad breath, and the more unpleasant the feeling in the oral cavity, while the lower the score, the less the stickiness in the oral cavity, the stronger the bad breath, and the more unpleasant the feeling in the oral cavity. It is said that oral bacteria such as periodontal disease bacteria and tooth decay bacteria grow by feeding on food debris in the mouth, and produce sticky mucus four hours after a meal. In other words, stickiness in the oral cavity four hours after a meal indicates that bacteria have abnormally proliferated after a meal, and improvement indicates that bacterial proliferation has been suppressed. The results are shown in Table 7.

As shown in Table 7, mouthwash using Shini-seihai-to extract significantly improved stickiness, as well as bad breath and discomfort. This indicates that the proliferation of bacteria in the oral cavity was suppressed.

Test Example 5
In the oral cavity, periodontal disease bacteria and dental caries bacteria grow during sleep. Therefore, eight subjects (men and women in their 20s and 30s) who were concerned about stickiness in the oral cavity were asked to rinse their mouths with 50 mL of tap water within one hour of waking up, and then their tongues were swabbed with a sterile cotton swab according to the instruction manual of a Panasonic bacteria counter (product number: DU-AA01NP-H) to measure the number of bacteria. Next, within one hour of waking up the next day, the subjects were asked to rinse their mouths with half the amount of the Shini-seihai-to extract prepared in Test Example 1, which was dissolved in 100 mL of tap water at 2.25 g (14 g in terms of raw herbal medicine, 1.5 g in terms of raw herbal medicine of Zhimo), and after rinsing their mouths lightly, the number of bacteria was measured in the same manner as the previous day. After waking up, the subjects were not allowed to brush their teeth or eat or drink until the end of the test. The results are shown in Table 8.

As is clear from Table 8, mouthwashing with Shini-seihai-to extract reduced the number of bacteria in the oral cavity. In other words, it demonstrated an antibacterial effect against oral bacteria.

Claims (7)

Contains extract of Shini Seihaitou,
For adults, the dose of the extract in terms of raw herbal medicine is 8.4 g to 21 g per day , taken three times a day .
An antibacterial agent for use in an application that targets bacteria selected from the group consisting of Streptococcus mutans, Fusobacterium, Clostridium sobrinus, Propionibacterium acnes, and Haemophilus influenzae , and does not target Staphylococcus aureus. The present invention comprises an extract of a herbal medicine selected from the group consisting of Keigakurenkyoto, Kakkonto-ka-senkyu-shini, and Shoseiryu-to,
For adults, the dose of the extracts in terms of the raw herbal medicine equivalent is 14.2 g/day to 21.38 g/day for Keikakurenkyoto, 12 g/day to 18 g/day for Kakkonto-ka-senkyu-shini, and 8.1 g/day to 20.3 g/day for Sho-seiryu -to, taken three times a day .
An antibacterial agent that targets Streptococcus pneumoniae and is used in applications that do not target Staphylococcus aureus. The antibacterial agent according to claim 1 or 2, which is applied to subjects who have taken an antibacterial agent having antibacterial activity against Staphylococcus aureus within the past year. The antibacterial agent according to claim 1, for use against upper respiratory tract infections and inflammation caused by bacteria selected from the group consisting of Streptococcus mutans, Fusobacterium spp., Clostridium sobrinus, Propionibacterium acnes, and Haemophilus influenzae. The antibacterial agent according to claim 1 for use against at least one of oral infections, skin infections, and lower respiratory tract infections, and inflammation caused by these infections, caused by bacteria selected from the group consisting of Streptococcus mutans, Fusobacterium spp., Clostridium sobrinus, Propionibacterium acnes, and Haemophilus influenzae. The antibacterial agent according to claim 2, for use against upper respiratory tract infections caused by pneumococcus and inflammation resulting therefrom. The antibacterial agent according to claim 2, for use against at least one of oral infections, skin infections, and lower respiratory tract infections caused by pneumococcus, and inflammation caused by these infections.