Use of Eugenol Acetate as an Agent Against Bad Breath

Abstract

The use of eugenol acetate as an agent (i) for inhibiting and/or preventing the growth of and/or for killing microorganisms which cause bad breath and/or (ii) for combating bad breath is described.

Description

EXAMPLES

Unless stated otherwise, all the data relate to the weight.

In Vitro Test for Reduction of Bad Breath

The test is based on the work of Goldberg and Rosenberg (Production of Oral Malodor in an in vitro System, S. Goldberg and M. Rosenberg, pp.143-150, in: Bad Breath—A Multidisciplinary Approach, eds: D. van Steenberghe, M. Rosenberg, Leuven University Press, 1996) and was adapted for better reproducibility.

A sterile liquid medium inoculated with fresh morning saliva is incubated at 37 ° C. for some days and then smelled by a panel of testers.

An intensive, typical bad breath odour had formed. Non-inoculated controls have only a weak smell of the medium.

Triclosan® (5-chloro-2-(2,4-dichlorophenoxy)phenol) was added to inoculated samples in a concentration of 0.05% as a control for the tests. After the incubation time, the inoculated and Triclosan®-treated samples had the same weak media smell as the non-inoculated samples.

By addition of 0.01% eugenol acetate to inoculated samples, no smell—analogously to Triclosan®—was to be found after the incubation time. This value also corresponds to the minimum active concentration. At significantly lower concentrations than 0.01%, a changed intrinsic smell or a mixed smell was perceptible in some cases.

If 0.05% eugenol acetate is added to the inoculated medium only one hour before the sensory evaluation, an unpleasant mixed smell of bad breath and a weak eugenol acetate note is to be observed. This observation demonstrates that the action of eugenol acetate against bad breath is not an odour-masking/-covering action.

Determination of the Minimum Inhibitory Concentration

The minimum inhibitory concentration (MIC) of eugenol acetate was determined in the series dilution test against various bacteria. The result is shown in the following table:

Organism	MIC [ppm]	Type
Escherichia coli	>1,000	no action up to 1,000 ppm
Pseudomonas aeruginosa	>1,000	no action up to 1,000 ppm
Staphylococcus aureus	>1,000	no action up to 1,000 ppm
Streptococcus mutans	>1,000	no action up to 1,000 ppm
Fusobacterium nucleatum	500	bactericidal
Prevotella intermedia	500	bactericidal
Porphyromonas gingivalis	1,000

A bactericidal action was thus detected against the germs Fusobacterium nucleatum and Prevotella intermedia, which cause bad breath, at a concentration of 500 ppm eugenol acetate. An activity against Porphyromonas gingivalis was furthermore observed, and an MIC of 1,000 ppm was determined.

In a further test in a concentration of 1,000 ppm, eugenol acetate showed no significant reduction in respect of the total number of germs in the oral saliva samples investigated.

FORMULATION EXAMPLES

1. Gel Dental Cream with an Activity Against Bad Breath

	I (%)	II (%)	III (%)
Na carboxymethylcellulose	0.40	0.40	0.40
Sorbitol 70%, in water	72.00	72.00	72.00
Polyethylene glycol (PEG) 1500	3.00	3.00	3.00
Na saccharinate	0.07	0.07	0.07
Na fluoride	0.24	0.24	0.24
p-Hydroxybenzoic acid (PHB) ethyl	0.15	0.15	0.15
ester
Aroma A	0.80	1.10	1.00
Eugenol acetate	0.025	0.06	0.2
Abrasive silica	11.00	11.00	11.00
Thickening silica	6.00	6.00	6.00
Sodium dodecyl sulfate (SDS)	1.40	1.40	1.40
Dist. water	to 100.00	to 100.00	to 100.00

Aroma A here had the following composition:

30 wt. % I-menthol, 30 wt. % peppermint oil Mentha piperita, 21.5 wt. % peppermint oil Mentha arvensis, 9 wt. % anethole, 0.5 wt. % anisaldehyde, 2 wt. % eucalyptol, 1 wt. % Eucalyptus globulus oil, 3 wt. % menthone, 1 wt. % spearmint oil, 1 wt. % basil oil, 0.5 wt. % menthyl acetate, 0.05 wt. % menthyl lactate, 0.1 wt. % menthyl-3-carboxylic acid N-ethylamide (WS-3), 0.05 wt. % 2-hydroxyethyl menthyl carbonate (Frescolat MGC, Symrise), 0.05 wt. % 2-hydroxypropyl menthyl carbonate (Frescolat MPC, Symrise), 0.1 wt. % pinene, 0.1 wt. % propylene glycol, 0.05 wt. % limonene.

2. Dental Cream Against Plaque with an Activity Against Bad Breath

	I (%)	II (%)	III (%)
Na carboxymethylcellulose	1.00	1.00	1.00
Glycerol	12.50	12.50	12.50
Sorbitol 70%, in water	29.00	29.00	29.00
Na saccharinate	0.20	0.20	0.20
Na fluoride	0.22	0.22	0.22
Azacycloheptane-2,2-diphospho acid,	1.00	1.00	1.00
di-sodium salt
Bromochlorophene	0.10	0.10	0.10
Peppermint aroma	1.10	1.10	1.10
Eugenol acetate	0.025	0.05	0.15
Abrasive silica	15.00	15.00	15.00
Thickening silica	5.00	5.00	5.00
Sodium dodecyl sulfate (SDS)	1.50	1.50	1.50
Dist. water	to 100.00	to 100.00	to 100.00

3. Dental Cream Against Plaque with an Activity Against Bad Breath

Base: silica, alkali metal diphosphate

	I (%)	II (%)	III (%)
Carrageenan	0.90	0.90	0.90
Glycerol	15.00	15.00	15.00
Sorbitol 70%, in water	25.00	25.00	25.00
PEG 1000	3.00	3.00	3.00
Na fluoride	0.24	0.24	0.24
Tetrapotassium diphosphate	4.50	4.50	4.50
Tetrasodium diphosphate	1.50	1.50	1.50
Na saccharinate	0.40	0.40	0.40
Precipitated silica	20.00	20.00	20.00
Titanium dioxide	1.00	1.00	1.00
PHB methyl ester	0.10	0.10	0.10
Menthol/eucalyptol aroma	1.10	1.10	1.10
Eugenol acetate	0.05	0.30	0.50
Sodium dodecyl sulfate	1.30	1.30	1.30
Dist. water	to 100.00	to 100.00	to 100.00

4. Dental Cream Against Sensitive Teeth with an Activity Against Bad Breath

	I (%)	II (%)	III (%)
Na carboxymethylcellulose	0.70	0.70	0.70
Xanthan gum	0.50	0.50	0.50
Glycerol	15.00	15.00	15.00
Sorbitol 70%, in water	12.00	12.00	12.00
K nitrate	5.00	5.00	5.00
Na monofluorophosphate	0.80	0.80	0.80
PHB methyl ester	0.15	0.15	0.15
PHB propyl ester	0.05	0.05	0.05
Na saccharinate	0.20	0.20	0.20
Menthol/anethole aroma	1.00	1.00	1.00
Eugenol acetate	0.025	0.10	0.20
Ca carbonate	35.00	35.00	35.00
Silicon dioxide	1.00	1.00	1.00
Sodium dodecyl sulfate	1.50	1.50	1.50
(SDS)
Dist. water	to 100.00	to 100.00	to 100.00

5. Dental Cream Against Sensitive Teeth with an Activity Against Bad Breath

	I (%)	II (%)	III (%)
	Hydroxyethylcellulose	1.40	1.40	1.40
	Guar gum	0.60	0.60	0.60
	Glycerol	18.00	18.00	18.00
	Sorbitol 70%, in water	12.00	12.00	12.00
	Na saccharinate	0.35	0.35	0.35
	Dyestuff	0.01	0.01	0.01
	PHB methyl ester	0.15	0.15	0.15
	PHB propyl ester	0.04	0.04	0.04
	Sr chloride	10.50	10.50	10.50
	Peppermint/aniseed	1.20	1.20	1.00
	aroma
	Eugenol acetate	0.025	0.10	0.25
	Precipitated silica	15.00	15.00	15.00
	Silicon dioxide	1.60	1.60	1.60
	Sodium dodecyl	1.30	1.30	1.30
	sulfate
	Dist. water	to 100.00	to 100.00	to 100.00

6. Ready-to-Use Mouth Wash with Fluoride and an Activity Against Bad Breath

	I (%)	II (%)	III (%)
Ethanol	7.00	7.00	7.00
Glycerol	12.00	12.00	12.00
Na fluoride	0.05	0.05	0.05
Pluronic F-127 ® (BASF,	1.40	1.40	1.40
surface-active substance)
Na phosphate buffer pH 7.0	1.10	1.10	1.10
Sorbic acid	0.20	0.20	0.20
Na saccharinate	0.10	0.10	0.10
Menthol/peppermint aroma	0.15	0.20	0.15
Eugenol acetate	0.01	0.05	0.08
Dyestuff	0.01	0.01	0.01
Dist. water	to 100.00	to 100.00	to 100.00

7. Mouth Wash Concentrate with an Activity Against Bad Breath

	I (%)	II (%)	III (%)
Ethanol, 95% strength	80.00	80.00	80.00
Na cyclamate	0.15	0.15	0.15
Menthol/aniseed/eucalyptol	3.50	1.0	3.50
aroma
Dyestuff	0.01	0.01	0.01
Eugenol acetate	0.50	1.5	2.5
Dist. water	to 100.00	to 100.00	to 100.00

b 8. Chewing Gum Against Bad Breath

	I (%)	II (%)	III (%)
	Chewing gum base	21.00	21.00	21.00
	Glucose syrup	16.50	16.50	16.50
	Glycerol	0.50	0.50	0.50
	Powdered sugar	60.45	60.40	60.30
	Menthol/spearmint aroma	1.50	1.50	1.20
	Eugenol acetate	0.05	0.10	0.50

9. Sugar-Free Chewing Gum Against Bad Breath

	I (%)	II (%)	III (%)
	Chewing gum base	30.00	30.00	30.00
	Sorbitol, powder	38.45	38.40	38.30
	Palatinite	9.50	9.50	9.50
	Xylitol	2.00	2.00	2.00
	Mannitol	3.00	3.00	3.00
	Aspartame	0.10	0.10	0.10
	Acesulfame K	0.10	0.10	0.10
	Emulgum/emulsifier	0.30	0.30	0.30
	Sorbitol 70%, in water	14.00	14.00	14.00
	Glycerol	1.00	1.00	1.00
	Menthol/aniseed/cinnamon	1.50	1.50	1.50
	aroma
	Eugenol acetate	0.05	0.10	0.20

10. Gelatine Capsules Against Bad Breath for Direct Consumption

	I (%)	II (%)	III (%)
	Gelatine shell:
	Glycerol	2.014	2.014	2.014
	Gelatine 240 Bloom	7.91	7.91	7.91
	Sucralose	0.065	0.065	0.065
	Allura Red	0.006	0.006	0.006
	Brilliant Blue	0.005	0.005	0.005
	Core composition:
	Plant oil triglyceride	80.0	70.0	60.0
	(coconut oil fraction)
	Aroma B	7.0	12.0	15.0
	Eugenol acetate	3.0	8.0	15.0

Aroma B here had the following composition (data in each case in wt. %):

0.1% neotame powder, 0.05% aspartame, 29.3% peppermint oil arvensis, 29.3% peppermint piperita oil Willamette, 2.97% sucralose, 2.28% triacetin, 5.4% diethyl tartrate, 12.1% peppermint oil yakima, 0.7% ethanol, 3.36% 2- hydroxyethyl menthyl carbonate, 3.0% 2-hydroxypropyl menthyl carbonate, 0.27% vanillin, 5.5% D-limonene, 5.67% L-menthyl acetate.

The gelatine capsule, which is suitable for direct consumption, had a diameter of 5 mm, and the weight ratio of core material to shell material was 90:10. The capsules opened in the mouth within less than 10 seconds and dissolved completely within less than 50 seconds.

Claims

1. A method of inhibiting the growth of micro-organisms causing bad breath and/or to combat bad breath by adding thereto to a composition comprising eugenol acetate in an amount sufficient to act as an agent (i) for inhibiting and/or preventing the growth of and/or for killing microorganisms which cause bad breath and/or (ii) for combating bad breath.

2. A method according to claim 1, wherein the microorganisms which cause bad breath are chosen from the group consisting of: Eubacterium, Fusobacterium, Haemophilus, Neisseria, Porphyromonas, Prevotella, Treponema and Veillonella species.

3. An oral hygiene product containing eugenol acetate in an amount of at least 0.01 wt. %, based on the total weight of the product, wherein the weight ratio of eugenol acetate to eugenol is greater than 1:5 if the product contains eugenol.

4. An oral hygiene product according to claim 3, containing an amount of eugenol acetate in the range from 0.025 to 5.0 wt. %, based on the total weight of the product.

5. An oral hygiene product according to claim 3, wherein the weight ratio of eugenol acetate to eugenol is greater than 1.1.

6. An oral hygiene product according to claim 3, containing an aroma composition which comprises menthol and optionally one or more substances having an aniseed note and/or eucalyptol and/or one or more herbal components.

7. An oral hygiene product according to claim 3, containing 0.05 to 3 wt. % eugenol acetate and0.05 to 10 wt. %, of an aroma composition which comprises menthol and optionally one or more substances having an aniseed note and/or eucalyptol and/or one of more herbal components.

8. An oral hygiene product according to claim 3, containing 0.05 to 3 wt. % eugenol acetate and0.05 to 10 wt. %, of an aroma composition which comprises racemic menthol and/or 1-menthol, anethole, eucalyptol and optionally one or more herbal components, the weight ratio of eugenol acetate to menthol being in the range of 10:1 to 1:10.

9. An oral hygiene product according to claim 3, which is substantially free from eugenol.

10. A method of inhibiting and/or preventing the growth of and/or for killing microorganisms which cause bad breath comprising the following steps: bringing microorganisms which cause bad breath into contact with an amount of eugenol acetate which is antimicrobially active against these microorganisms.

11. A method of combating bad breath comprising the following step introducing an amount of eugenol acetate which is antimicrobally active against microorganisms which cause bad breath into the oral cavity and/or the pharyngeal cavity.