Patent Application
20210161143
The present invention relates to an antiseptic composition (disinfectant composition) containing olanexidine gluconate and having a broader bactericidal spectrum.
Olanexidine, chemical name 1-(3,4-dichlorobenzyl)-5-octylbiguanide, is a compound with a high bactericidal activity. Olanexidine gluconate has sufficient water solubility, a broad bactericidal spectrum, demonstrates a bactericidal effect in a short time, further sustains such an effect for an extended period of time, and is highly safe, thereby to be useful as a medical disinfectant (Patent Document 1). Dermal bactericidal disinfectants containing olanexidine gluconate have good efficacy on various bacteria which are considered as normal bacteria on skin and enveloped viruses, while substantially have no efficacy on feline calicivirus which has no envelope (Non-patent Document 1). For this reason, in the fields such as medical and nursing, and food and drink industries, olanexidine gluconate-containing disinfectants having more efficacies with a broader bactericidal spectrum are in demand.
Olanexidine belongs to monobiganide-based compounds which have 1 biganide structure. Examples of the disinfectant having the same biganide structure representatively include chlorhexidine, which is a bisbiganide-based compound, and polyhexamethylene biguanide, which is a polybiganide-based compound.
Chlorhexidine is a bisbiganide-based compound having 2 biganide structures in a molecule. As with olanexidine, chlorhexidine is hardly water-soluble and becomes soluble in the form of gluconate, for the reason of which it is mainly used in the form of chlorhexidine gluconate as a pharmaceutical product (Non-patent Document 2). Chlorhexidine gluconate, as with olanexidine gluconate, shows a viricidal action on enveloped viruses, while having no efficacy on non-enveloped viruses (Non-patent Document 3). Further, chlorhexidine gluconate is stable at pH 4 to 6.5 and is known to cause precipitation when a dilute aqueous solution is basic of pH 8 or more and cause no difference in the bactericidal efficacies even when pH is increased (Patent Document 2, Non-patent Document 2, and Non-patent Document 4).
On the other hand, polyhexamethylene biganide, classified as a polybiganide-based compound, is a polymer of hexamethylene biganide having 1 biganide structure in a unit. Polyhexamethylene biganide is extremely easily soluble in water and has a broad bactericidal spectrum, for the reason of which a mild acidic solution thereof is commonly available as a low toxic sterilizing agent (Non-patent Documents 5 and 6). Further, commercial polyhexamethylene biganide disinfectants are reported as having viricidal activities on non-enveloped viruses (Non-patent Document 7) and further reported as increasing bactericidal efficacy and viricidal efficacy when pH is further increased (Non-patent Document 4 and Patent Documents 3 and 4).
[Non-patent Document 3] Clin Microbiol Rev.; 12(1): 147-179 (January, 1999)
An object of the present invention is to provide an antiseptic composition with a more extended applicable range by further enhancing the efficacy of olanexidine gluconate, which has been used as a highly safe dermal bactericidal disinfectant, and extending bactericidal spectrum.
The present inventors continued extensive studies to solve the above object. Conventional bactericides containing olanexidine gluconate were formulated to be pH (Non-patent Document 1) because compositions applied to skins are generally mildly acidic according to pH (pH 4 to 7) of skins and olanexidine deposits in the form of a free compound when neutralized with an alkaline aqueous solution (Patent Document 1), however, the present inventors intentionally prepared a basic solution of olanexidine gluconate to test activities thereof and found that bactericidal efficacies are not only unexpectedly enhanced but efficacies are demonstrated on non-enveloped viruses against which a mildly acidic formulation thereof had substantially no efficacy. Further, the present inventors confirmed that further addition of a surfactant to a basic solution containing olanexidine gluconate enhances the stability. The present invention is based on the above findings.
More specifically, the present invention is as follows.
According to a composition of the present invention, a disinfectant usable in the fields such as medical and nursing, and food and drink industries and having higher efficacy with a broader bactericidal spectrum can be produced.
The present invention relates to an antiseptic composition which comprises olanexidine gluconate and is basic. Being basic used herein may be any composition of pH being more than 7 but examples include, in view of toxicity and a bactericidal activity to skins, pH being more than 7 to 12, pH being more than 7 to 11.5, pH being more than 7 to 11, pH being more than 7 to 10.5, and pH being more than 7 to 10; preferably pH 7.5 to 12, pH 7.5 to 11.5, pH 7.5 to 11, pH 7.5 to 10.5, and pH 7.5 to 10; more preferably pH 8 to 11.5, pH 8 to 11, pH 8 to 10.5, pH 8 to 10; further preferably pH 8.5 to 11.5, pH 8.5 to 11, pH 8.5 to 10.5, and pH 8.5 to 10; and furthermore preferably pH 9 to 12, pH 9 to 11.5, pH 9 to 11, pH 9 to 10.5, and pH 9 to 10. Note that the composition of the present invention is an aqueous solution. Further, in the present Description, the “disinfection” and “bactericidal” mean to kill bacteria, fungi and/or viruses.
Any known pH adjuster can be used to adjust the pH, but examples include a basic solution such as sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonium carbonate, and potassium carbonate, of which sodium hydroxide is preferable. Further, the composition of the present invention is optionally prepared using a basic buffer, and examples of the buffer used include a boric acid-sodium carbonate buffer, a CAPS-NaOH buffer, a Bicine-NaOH buffer, a Glycine-NaOH buffer, a Tricine-NaOH buffer, a HEPPS-NaOH buffer, a TAPS-NaOH buffer, a Bicine-NaOH buffer, and a HEPES-NaOH buffer.
The concentration of olanexidine gluconate is not particularly limited as long as it has sufficient bactericidal efficacy, but examples include 0.01 to 20% (W/V), preferably 0.1 to 10% (W/V), and more preferably 0.5 to 5% (W/V). When the antiseptic alcohol to be described later is used concurrently, examples of such a concentration include 0.01 to 10% (W/V), preferably 0.1 to 7% (W/V), more preferably 0.5 to 5% (W/V), and further preferably 0.5 to 3% (W/V).
A composition of the present invention has more promoted bactericidal activities on filamentous fungi and acid-fast bacteria, particularly bacteria of the genus Microsporum and bacteria of the genus Mycobacterium. Further, the present composition also has good viricidal activities even on non-enveloped viruses, particularly viruses of the family Caliciviridae (viruses of the genus Norovirus), against which the conventional olanexidine gluconate-containing disinfectants failed to inactivate.
A composition of the present invention further optionally contains an antiseptic alcohol to potentiate bactericidal activities and impart quick-dryness. Examples of the antiseptic alcohol herein preferably include ethanol and isopropyl alcohol, and examples of the antiseptic alcohol concentration include 10 to 85% (V/V), 20 to 85% (V/V), 30 to 85% (V/V), 40 to 85% (V/V), 50 to 85% (V/V), 10 to 80% (V/V), 20 to 80% (V/V), 30 to 80% (V/V), 40 to 80% (V/V), 50 to 80% (V/V), 10 to 70% (V/V), 20 to 70% (V/V), 30 to 70% (V/V), 40 to 70% (V/V), and 50 to 70% (V/V). A composition of the present invention may not substantially contain an antiseptic alcohol. Containment of the antiseptic alcohol enables to prepare a quick-drying disinfectant having both potentiating effects of bactericidal activities due to the antiseptic alcohol and sustained effects of bactericidal activities due to olanexidine gluconate. Further, as bactericidal activities are potentiated due to the antiseptic alcohol, a concentration of olanexidine gluconate can be reduced. Examples of the concentration ratio of the olanexidine gluconate to the antiseptic alcohol include 1:400 to 1:20, preferably 1:300 to 1:30, and more preferably 1:200 to 1:40.
A composition of the present invention can further contain a known bactericide. Examples of the bactericide include a benzalkonium salt such as benzalkonium chloride and benzalkonium alkyl phosphate, benzethonium chloride, triclosan, isopropyl methylphenol, cetylpyridinium chloride, resorcin, trichlorocarbanilide, chlorhexidine hydrochloride, chlorhexidine gluconate, polyhexamethylene biganide, sodium hypochlorite, hydrogen peroxide, povidone iodine, and iodine tincture. These bactericides are optionally used singly or 2 or more may be used in combination.
A composition of the present invention can further contain a known solubilizer. Examples of the solubilizer include a nonionic surfactant, an ionic surfactant, ethylenediamine, sodium benzoate, nicotinamide, cyclodextrin, ethanol, benzyl alcohol, and propylene glycol. Examples of the ionic surfactant preferably include an alkyl dimethylamine oxide such as an oleyl dimethylamine oxide, a stearyl dimethylamine oxide, a palmityl dimethylamine oxide, a myristyl dimethylamine oxide, a lauryl dimethylamine oxide, and a coconut oil alkyl dimethylamine oxide, of which a lauryl dimethylamine oxide is preferable. Examples of the nonionic surfactant include a sorbitan fatty acid ester, a polyoxyethylene sorbitan fatty acid ester, a polyoxyethylene alkyl ether, a polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene polyoxypropylene glycol, a polyglyceryl fatty acid ester, a polyoxyethylene hydrogenated castor oil, and a sucrose fatty acid ester, of which polyoxyethylene polyoxypropylene glycol, a polyoxyethylene alkyl ether, and a polyoxyethylene polyoxypropylene alkyl ether are preferable. Examples of the polyoxyethylene polyoxypropylene glycol include polyoxyethylene(42) polyoxypropylene(67) glycol (Pluronic (R) P-123), polyoxyethylene(54) polyoxypropylene(39) glycol (Pluronic (R) P-85), polyoxyethylene(196) polyoxypropylene (67) glycol (Pluronic (R) F-127), polyoxyethylene(3) polyoxypropylene(17) glycol (Pluronic (R) L-31), polyoxyethylene(20) polyoxypropylene(20) glycol (Pluronic (R) L-44), polyoxyethylene(120) polyoxypropylene(40) glycol (Pluronic (R) F-87), and polyoxyethylene(160) polyoxypropylene(30) glycol (Pluronic (R) F-68), of which polyoxyethylene(20) polyoxypropylene(20) glycol (Pluronic (R) L-44) is preferable. Examples of the polyoxyethylene alkyl ether include a polyoxyethylene cetylether, a polyoxyethylene oleyl ether, and a polyoxyethylene lauryl ether (lauromacrogol), with a polyoxyethylene lauryl ether (lauromacrogol) being particularly preferable. Further, examples of the polyoxyethylene polyoxypropylene alkyl ether include a polyoxyethylene(20) polyoxypropylene(4) cetylether, a polyoxyethylene(30) polyoxypropylene(6) decyltetradecyl ether, a polyoxyethylene(25) polyoxypropylene(25) lauryl ether, with a polyoxyethylene(20) polyoxypropylene(4) cetylether being particularly preferable. The concentration of a solubilizer may be a concentration which prevents olanexidine gluconate from precipitating and does not reduce the bactericidal activity and is usually determined in accordance with a concentration of olanexidine gluconate within a concentration range of 0.1 to 30% (W/V).
A composition of the present invention optionally contains an anti-inflammatory agent, a moisturizer, an emollient agent, a touch improver, and a thickener.
Examples of the anti-inflammatory agent include a licorice extract, glycyrrhetinic acid, dipotassium glycyrrhizinate, stearyl glycyrrhetinate, tocopherol acetate, allantoin, and an aloe extract.
Example of the moisturizer include an amino acid, a fatty acid ester, pyrrolidone carboxylic acid, sodium pyrrolidone carboxylate, sodium lactate, hyaluronic acid, sodium hyaluronate, N-cocoyl-L-arginine ethyl ester-DL-pyrrolidone carboxylate, urea, sorbitol, trehalose, 1,3-butylene glycol, propylene glycol, poloxamer (Pluronic (R) F-68, etc.), and glycerin.
Examples of the emollient include a fatty acid ester such as isopropyl myristate, isopropyl palmitate, isopropyl stearate, isobutyl oleate, and isobutyl maleate, and 1 fatty acid ester singly or 2 or more of these can be contained.
Examples of the touch improver include a silicone-based compound such as dimethylpolysiloxane and cyclic silicone.
Examples of the thickener include a cellulose derivative such as hydroxyethyl cellulose, hydroxypropyl cellulose, hydrophobic hydroxypropyl methylcellulose, methyl cellulose, and carboxymethyl cellulose, a (meth)acrylic acid base copolymer, polyvinyl alcohol, polyvinylpyrrolidone, a methyl vinyl ether-maleic anhydride copolymer, polyacrylamide, alginic acid, sodium alginate, propylene glycol alginate, gelatin, a gum arabic, a gum tragacanth, a locust bean gum, a guar gum, a tamarind gum, a xanthan gum, a gellan gum, and carrageenan.
A composition of the present invention can preferably be used for the purpose of disinfecting the instrument surfaces of medical instruments, cookware, and nursing equipment, and skin surfaces such as hands and fingers. A composition of the present invention is optionally used as soaked in paper, cloth, non-woven fabric, cotton swab, or absorbent cotton, or as filled in an applicator for application, or in the form of a rubbing agent or a scrubbing agent, but a composition of the present invention is preferably used as a rubbing agent. The rubbing agent herein means a quick-drying rubbing-type formulation, and the scrubbing agent means a formulation obtained by mixing a bactericide/disinfectant and a surfactant having detergency. Note that when a composition of the present invention is used for disinfecting fingers of both hands, an amount usually used per disinfection is 1 to 5 ml, preferably 1.5 to 4.5 ml, more preferably 2 to 4 ml, and further preferably 2.5 to 3.5 ml, and examples of the number of times used per day include, in view of dermal toxicity, within 100 times, preferably within 80 times, more preferably within 60 times, and further preferably within 40 times.
Hereinafter, the present invention will be described more specifically in reference to examples, but technical ranges of the present invention are not limited thereto.
Bactericidal power of olanexidine gluconate containing-compositions (pH5, 8 to 10) against filamentous fungi and non-tuberculous mycobacteria, which are known to cause infections, was evaluated by Time-kill test.
To 19 g of Difco Middlebrook 7H10 Agar (product number: 262710, manufactured by Becton, Dickinson and Company), 5 mL of glycerol (product number: 070-04941, manufactured by Wako Pure Chemical Industries, Ltd.) and 900 mL of pure water were added and stirred. The medium was steam-sterilized under pressure (121° C., 20 minutes). After sterilization, the medium was taken out from the pressure steam sterilizer, cooled to 50 to 55° C. with stirring, and subsequently 100 mL of BBL Middlebrook OADC Enrichment (product number: 212240, manufactured by Becton, Dickinson and Company) was added and stirred. About 20 mL each of the agar, before set, was dispensed in petri dishes and allowed to be solidified.
To 65 g of a Sabouraud agar medium “Nissui” (product number: 05701, manufactured by NISSUI PHARMACEUTICAL CO., LTD.), 1000 mL of pure water was added and stirred. The medium was steam-sterilized under pressure (121° C., 20 minutes). About 20 mL each of the agar, before set, was dispensed in petri dishes and allowed to be solidified.
To 73 g of a Sabouraud-Dextrose LP Agar medium “DAIGO” (product code: 392-01875, manufactured by NIHON PHARMACEUTICAL CO., LTD.), 1000 mL of pure water was added and stirred. The medium was steam-sterilized under pressure (121° C., 20 minutes). About 20 mL each of the agar, before set, was dispensed in petri dishes and allowed to be solidified.
To about 800 mL of distilled water, 100 g of polysorbate 80, 5.0 g of a sodium thiosulfate hydrate, 0.4 g of potassium dihydrogen phosphate, 1 mL of Triton X-100, 10.1 g of disodium hydrogen phosphate anhydrous, and 11.7 g of soy lecithin were added and stirred. Further, 10.0 g of Tamol (R) NN8906 was added, and heated and stirred until dissolved. After dissolution, a 1 mol/L sodium hydroxide solution was added to adjust pH to 7.8 to 7.9. Distilled water was added until the total amount was 1000 mL, and then steam-sterilization under pressure was carried out.
For test microorganisms, filamentous fungus Microsporum canis NBRC 32464, acid-fast bacteria Mycobacterium chelonae JCM 6388 and Mycobacterium fortuitum JCM 6387 were used. Each of the test microorganisms was cultured on the 7H10 plate (Mycobacterium chelonae and Mycobacterium fortuitum) or the SAB plate (Microsporum canis), and then suspended in distilled water to prepare test microorganism solutions of McFarland No.1 (Mycobacterium chelonae and Mycobacterium fortuitum) or of McFarland No.5 (Microsporum canis).
LR=A−B
With Mycobacterium chelonae and Mycobacterium fortuitum, the mixing ratio of the reaction solution to the neutralizer is 1:99 and the smear amount is 100 μL, because of which the minimum limit of detection of a viable cell count is 1000 CFU/mL (3 in common logarithm value). Further, with Microsporum canis, the mixing ratio of the reaction solution to the neutralizer is 1:9 and the smear amount is 100 μL, because of which the minimum limit of detection of a viable cell count is 100 CFU/mL (2 in common logarithm value). When a colony was not detected, the minimum limit of detection was adopted and LR is indicated with a sign of inequality “>”.
The results are shown in Tables 1 to 3 and
Mycobacterium fortuitum JCM 6387
Mycobacterium chelonae JCM 6388
The above results revealed that, in all test microorganisms, bactericidal powers of the olanexidine formulations at pH 8 to 10 are more intense than the olanexidine formulation at pH 5. Note that the bactericidal power of the olanexidine formulation at pH 10 is more reduced than the olanexidine formulation at pH 8, but this is considered that the activity was prohibited by Pluronic L-44 added as the solubilizer.
Bacteriophage MS2 is known to be resistant to disinfectants and is used for an alternative test such as the norovirus killing action of disinfectants. For this reason, viricidal effects of the olanexidine formulations prepared by changing pH and a commercial disinfectant on a virus were evaluated by a test using bacteriophage MS2.
To 1 L of pure water, 10 g of Polypepton, 2 g of a Yeast extract, and 1 g of MgSO4.7H2O were added and steam-sterilized under pressure (121° C., 20 minutes).
To 0.5 L of pure water, 5 g of Polypepton, 1 g of a Yeast extract, 0.5 g of MgSO4.7H2O, and 3.5 g of agar for a medium were added and steam-sterilized under pressure (121° C., 20 minutes).
To 64 g of a trypto-soya agar medium (SCD agar medium) “Nissui”, 1.6 L of pure water was added and stirred. The medium was steam-sterilized under pressure (121° C., 20 minutes). About 20 mL each of the agar, before set, was dispensed in petri dishes and allowed to be solidified.
To about 800 mL of distilled water, 100 g of polysorbate 80, 5.0 g of a sodium thiosulfate hydrate, 0.4 g of potassium dihydrogen phosphate, 1 mL of Triton X-100, 10.1 g of disodium hydrogen phosphate anhydrous, and 11.7 g of soy lecithin were added and stirred. Further, 10.0 g of Tamol (R) NN8906 was added, and heated and stirred until dissolved. After dissolution, a 1 mol/L sodium hydroxide solution was added to adjust pH to 7.8 to 7.9. Distilled water was added until the total amount was 1000 mL, and then steam-sterilization under pressure was carried out.
A phage solution prepared to about 6×1012 PFU/mL in accordance with a routine method was used.
Phage titer was calculated using the following (Equation 1).
PFU/t=(Σc1+c2+ . . . +cn) ((n1+n2×v2+ . . . +nn×vn)×d) (Equation 1)
A titer (PFU/mL) was converted to common logarithm (log10 PFU/mL) and indicated to the first decimal place by rounding off. When a titer (PFU/mL) was 1 or less, its common logarithm value was 0.
The viricidal (phage) action was evaluated by a Log10 reduction value.
LR=A−B
LR is indicated to the first decimal place by rounding off. Note that when a titer (common logarithm value) of the test substance after acted was 0, LR is indicated as “>(A−3)” because the phage titer has the minimum limit of detection of 3−log10.
Evaluation results on the viricidal actions of the test substances are shown in Table 4 and
The olanexidine formulation at pH 5 did not substantially show the viricidal action, and the viricidal action of the olanexidine formulation at pH 7 was equal to 70% ethanol used as the control substance, whereas the olanexidine formulations with the pH changed to basic tended to have larger LR as pH increased. The formulations at pH 8 or more had an LR of 3 or higher at 60 seconds and the formulation at pH 8.5 or more had an LR of 3 or higher at 30 seconds thereby to meet a requirement for the viricidal action of an ideal disinfectant of LR 3 or higher. Thus, a basic solution of olanexidine gluconate was revealed to have a practical viricidal activity and such a viricidal activity is intensified as pH increases.
In the present Example, ethanol was added to a basic olanexidine formulation of pH 9.5 to evaluate a viricidal effect by a test using bacteriophage MS2 for the purpose of confirming the quick-dryness imparting effect and the potentiating effect of the bactericidal activity by an antiseptic alcohol to a basic olanexidine formulation.
Substances to be tested 1 to 3, Comparative Example 1, and Base (control substance) were prepared by the compositions of the following Table 5.
Further, the following antiseptic ethanol was used as a control.
Viricidal effects were evaluated by the method using the bacteriophage MS2 described in the above Example 2, 2-1 and 2-2. Note that a phage solution prepared to about 4×1012 PFU/mL was used.
Evaluation results on viricidal actions of the test substances are shown in Table 6 and
The above results showed that the viricidal action increases in a concentration dependent manner of olanexidine gluconate even in the basic olanexidine formulation containing ethanol whereby the viricidal action by olanexidine gluconate is not impeded even when ethanol is added to impart quick-dryness. Further, the basic olanexidine formulation containing ethanol has a higher viricidal action compared with a basic olanexidine formulation which does not contain ethanol, for the reason of which the ethanol-containing basic olanexidine formulation showed to have a practical viricidal action even when an olanexidine gluconate concentration is reduced. Furthermore, a practical viricidal activity (LR or higher) was not found in the ethanol-containing olanexidine formulation having pH of less than 7 (Comparative Example 1), thereby suggesting that, in the basic olanexidine formulation containing ethanol, olanexidine gluconate, ethanol, and basicity synergistically contribute to the viricidal action. Note that, in the present Example, Pluronic F-68 was added for relieving rough skin and moisturization, and no difference in the effect was found even when Pluronic F-68 was 0.5 g/100 mL.
The composition of the present invention, when used, can produce an olanexidine gluconate-containing disinfectant having an improved bactericidal spectrum and an effect on non-enveloped viruses and is thus highly useful in the fields such as medical and nursing, and food and drink industries.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2018-135190 | Jul 2018 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2019/027803 | 7/12/2019 | WO | 00 |
