USOO6585961B1 (12) United States Patent (10) Patent No.: US 6,585,961 B1 Stockel (45) Date of Patent: Jul. 1, 2003 (54) ANTIMICROBIAL COMPOSITIONS 5,298.238 A 3/1994 Hussein 6,077,501. A * 6/2000 Sickora et al. (76) Inventor: Richard F. Stockel, 475 Rolling Hills 6.245,321 B1 * 6/2001 Nelson et al. Rd., Bridgewater, NJ (US) 08807 * cited by examiner (*) Notice: Subject to any disclaimer, the term of this Primary Examiner-Christopher R. Tate patent is extended or adjusted under 35 U.S.C. 154(b) by 0 days. ASSistant Examiner Randall Winston (57) ABSTRACT (21) Appl. No.: 10/016,611 Aqueous antimicrobial and biofilm removal compositions, (22) Filed: Nov.30, 2001 comprising essential oils and certain cationic, anionic, 7 amphoteric or non-ionic Surfactants individually or in com (51) Int. Cl. ............................ A61K 7/16; A61 K 7/26; bination having hydrophile-lipophile balance (HLB) of A61K 7/24; A61K 35/78 about 16 or above are effective oral mouthwashes and (52) U.S. Cl. ........................... 424/49; 424/58; 424/725; topical antimicrobial Solutions. Optionally C, C, benzyl, 424/55; 424/742 3-phenylpropanol or 2-phenylethanol alcohols can be added (58) Field of Search ............................ 424/725, 49, 58, Singularly or in combination from about 2 to about 2OV/w %. 424/55, 742 Other optically ingredients include antimicrobial enhances (56) References Cited and biofilm removal agents e.g., chelating compounds and U.S. PATENT DOCUMENTS certain organic acids. 4,657,758 A 4/1987 Goldemberg 5,174.990 A 12/1992 Douglas 21 Claims, No Drawings US 6,585,961 B1 1 2 ANTIMICROBAL COMPOSITIONS The carbon hydrogen - oxygen essential oils usually represent the more soluble portion of the oil. In this very BACKGROUND OF THE INVENTION broad class are included alcohols, aldehydes, ketones, and This invention relates to compositions comprising essen esters. AS in the case of the carbon-hydrogen essential oils, tial oils having antimicrobial activity with one or more many types are to be found Saturated and unsaturated cationic, anionic, or amphoteric Surfactants having a aliphatic as well as aromatic compounds, and also terpenic hydrophilic-lipophilic balance (HLB) or about 16 or greater. and Sesquiterpenic compounds (aliphatic, monocyclic, In particular, this invention relates to the employment of the bicyclic, and in the case of the Sesquiterpene compounds, combined essential oils and Surfactants as an effective even tricyclic). Other important constituents are phenols and antimicrobial and plaque removal oral rinse. Other uses are phenolic ethers, acids (usually esterified), lactones, oxides, also contemplated Such as a topical Solution to kill microbes and coumarins. Of lesser importance are the furan and remove biofilm from medical and dental equipment and derivatives, the coumarones, and the quinones. tubing. AS in the pharmaceutical industry where the chirality of Essential oils have long been known to have Some degree the bioactivity drug can play an important part in the of antimicrobial properties and Some degree of antiplaque 15 enhance activity, the same can be true with essential oils and their antimicrobial efficacy. When Stereoisomerism occurs, activity. However, Sufficient activity is lacking, until the the molecule can have enantiomers, which differ in Structure present invention. only in the left - and right handedness of their orientations. A wide variety of microorganisms are found in the oral Optical activity in essential oils exists primarily by having cavity, and among these are gram-positive anaerobic rods one or more chiral carbon atoms. Thus it is theoretically asSociated with the development of plaque Such as possible that one of the enantiomerS has greater antimicro Corynebacterium, Nocardia, Neisseria, and Streptococci, bial activity, then the racemic mixture. Of course, the Such as S. mutens, S. bovis, S. Salivarius, and gram-positive Separation of an optically active Substance would require Streptococci of the genus PeptostreptooccuS. additional expense, and unless there was a dramatic In addition, there is also present in plaque relatively Small 25 improvement at relative low costs, this methodology would amounts of other Substances Such as Salivary proteins, not be cost-effective. Nevertheless, the preparation or opti carbohydrates, epithelial cells and leukocytes. These organ cally active Separation resulting in a significant enhancement isms play a key role in the etiology of plaque. The bacterial of antimicrobial and/or biofilm removal capability is incor organisms associated with plaque formation produce a cap porated into the body of this invention. Sular material, which apparently causes the cells of the The following list illustrates the voluminous numbers of organism to adhere to each other, holding the plaque essential oils having varying degrees of antimicrobial activ together and allowing for further growth. For example, one ity (not all inclusive): anethol, anise oil, anol, bay oil, of the capsule forming bacteria, which occurs in large bergamot oil, camphor, carvacrol, carvone, cedar leaf oil, numbers in early plaque is Neisseria Sicca. citronel, eucalyptol, eugenol, guaiacol, hinokitiol, Removal of plaque and/or calculus by a dentist is cur 35 Isoeugenol, lavender oil, lemon oil, d-limonene, linalool, rently the only Safeguard against Serious gingival inflam menthol, methyl Salicylate, mustard oil, oil of cajeput, oil of mation caused by the accumulation of Significant amounts of cubeb, oil of Santal, Osimen, peppermint oil, phenolics, plaque. phenyl Salicylate, pimento, pine oil, rosemary oil, Safrale Conventional mouthwashes Serve primarily to Sweeten Sage oil, Saligenin, Sassafras oil, Spearmint oil, Storax, the breath, are formulated for that purpose, and are believed 40 Vanillin, wintergreen oil, and other Similar constituents. not to function in any in any Significant way to loosen or This invention is not limited by the above specific essen remove plaque from the dental Surfaces. tial oils. Many of the above components can be further There is a definite need in the art for an oral hygiene chemically modified to enhance antimicrobial activity and composition which, when used alone, or in conjunction with are therefore part of the Specifications of this invention a regular toothbrushing regime, renders the plaque present 45 concerning essential oils. on the dental Surface more Susceptible to removal. Furthermore, the Specification includes Stereoisomers ESSENTIAL OILS and/or geometrical isomers of essential oils having chirality, Essential oils which have the characteristic or flavor of the because it is known that there can be significant difference plant (or synthetically derived) from which they are obtained 50 in antimicrobial activity between the isomers. having long been used as antimicrobial agents. Most essen For the purpose of carrying out the experimental portion tial oils are composed of terpenes, oxygenated constituents, of this invention, the following well-known essential oils Sesquiterpenes, and a Small amount of a nonvolatile residue. were utilized; thymol, menthol, eucalyptol, and methyl The principal essential oil constituents can therefore be Salicylate were used. divided into two broad classes of organic compounds: those, 55 which contain only carbon and hydrogen, and those, which SURFACTANTS contain carbon, hydrogen and oxygen. Surfactants are often an important constituent of disin The carbon-hydrogen essential oils include paraffins, fectants. They are employed to achieve both uniform wetting olefins, aromatic hydrocarbons, terpenes (olefinic as well as of the Surface to be treated and frequently an additional mono and tricyclic) a few lower terpene homologs, Sesquit 60 cleaning effect. This is why particular attention should be erpenes (aliphatic as well as mono, bi, and tricyclic), given to this group of Substances when formulating a diterpones, and azulenes. Of these the terpenes and Sesquit disinfectant, as there are many ways in which the two groups erpenes are most characteristic of essential oils. The funda of compounds can interact. It is generally known that, for mental building block of the terpene Series is the isoprene instance, anionic Surfactants promote the inactivation of unit, Sometimes called a hemiterpene. Two Such units give 65 quaternary ammonium compounds. The same most likely rise to the terpenes, three to the Sesquiterpenes, four, to the applies to other positively charged biocides, e.g., betaines, diterpenes. guanidines, biguanides, etc. The inactivating effects are US 6,585,961 B1 3 4 generally obtained with Surfactant concentrations well above critical micelle concentration of about 0.75 to about 2.5 weight %. In contrast at lower concentrations improvements of the Solubility in water HLB Value Application biocide often occur. The cause of the improved action by Not dispersible 1. additional of low quantities of Surfactants is considered to be 2 an accumulation of the agent within micelles of the Surfac 3 tant which adsorb at the microorganism cell wall. The active 4 Water-in-oil emulsifier Substance thus becomes enriched at the cell wall which Poor dispersion 5 means that a lower does is required for the desired effect. 1O The property of Surfactant at a higher concentration to 6 inhibit the action of antimicrobial agents is attributed both to Unstable milky dispersion 7 complexing and Solubilizing in Surfactant micelles. In both 8 Wetting agent cases, the availability of full antimicrobial active Substance 9 is reduced.