Organic and Environmentally "Green" Biocide Compositions and Applications

Abstract

Natural, organic, environmentally “green” biocide compositions comprising oregano oil in various natural delivery media.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention (Technical Field)

The present invention relates to organic compositions and more particularly to compositions comprising essential oils and organic surfactants or solidifying agents.

2. Description of Related Art

Synthetic biocides, while effective, cannot be used in organic farming applications. Additionally, the cost of manufacturing their ingredients translates to their prices, which can be prohibitive for some farmers, particularly in developing nations. For instance, the fungi Rhizoctonia solani and Phytophthora capsici infect a wide variety of crops around the world. Alfalfa, peanut, soy, lima bean, cucumber, chili peppers, and corn are just a few of the over five hosts of R. solani in the United States alone, with many more affected worldwide. R. solani can cause collar and root rot, web blights on leaves and pods, callus formation, thickening of the collar area, plant stunting and poor vigor. The Ministry of Agriculture reported in 2011 that more than fifty plant species are susceptible to the adverse effects of P. capsici, which include necrotic lesions on vines, fruit rot, leaf wilting and moldy growth. Both R. solani and P. capsici are aggressive, hardy pathogens. Every year these pathogens devastate the production of crops for many farmers causing millions of dollars in losses. Similarly, plant pathogens such as the bacterium Xanthomonas campestris and the nematode Caenorhabditis elegans cause severe damage to both agricultural crops and turf grasses and there is a need for environmentally green, natural alternatives to current practices to control these pests.

Similarly, there is need for natural organic biocides for use in animal husbandry and human health applications. There has been a long felt need for biocides comprising natural constituents that are not toxic to humans and animals, and which have comparable effectiveness to that of synthetic biocides. For example, mastitis, caused by various bacteria infecting the teat canals of lactating cows and goats, remains without effective treatment. Also, human skin infections like onychomycosis, the fungal infection of human toenails, is not very effectively treated by synthetic chemicals and there is need for alternate effective, organic treatment ointments.

Embodiments of the present invention solve these problems. Embodiments of the present invention comprise compositions for organic, all-natural biocides with applications to control disease in plants, animals and humans.

BRIEF SUMMARY OF THE INVENTION

Embodiments of the present invention comprise organic natural compositions comprising: between approximately 0.0001% and approximately 20% oregano oil, water, and a natural, natural emulsifier to emulsify the oregano oil in the water and form a pesticide that when applied in an effective treatment dose kills plant pests. In one embodiment, the natural emulsifier is albumin at a ratio of between approximately 20 and approximately 5 parts oregano oil to 1 part albumin. In one embodiment a composition comprises between approximately 0.0005% and approximately 10% of oregano oil. In one embodiment, between approximately 0.001% and approximately 5% of oregano oil. In one embodiment the albumin is provided at a ratio of between approximately 15 and approximately 7 parts oregano oil to one part albumin. In one embodiment, the albumin is provided at a ratio of between approximately 12 and approximately 9 parts oil to 1 part albumin.

In a different embodiment, the natural emulsifier comprises natural saponins extracted from a desert plant, for example, of the genera Yucca, and between approximately 0.0005% and approximately 10% of oregano oil. In another embodiment, between approximately 0.001% and approximately 5% of oregano oil.

Another embodiment of the invention comprises an organic natural semisolid composition comprising between approximately 0.0001% and approximately 20% oregano oil, and a semisolid natural carrying medium to form a pesticide that when applied in an effective treatment dose kills plant pests. In one embodiment, the natural carrying medium is grain based flour selected from the group consisting of wheat, oat, rice, millet, and tapioca flour. In another embodiment, the composition further comprises an additive to prevent crumbling, for example, at a concentration ranging between approximately 0.001% and approximately 50%. In another embodiment, the additive is at a concentration of between approximately 0.01 and approximately 30%, or at a concentration of between approximately 0.1% and approximately 20%. In one embodiment, the additive is xanthum gum. In a different embodiment, the additive is guar gum. In one embodiment the composition comprises between approximately 0.01 and approximately 30% oregano oil. In another embodiment the composition comprises between approximately 0.1% and approximately 20% oregano oil.

In a different embodiment of the invention the composition's natural emulsifier is Tween 20.

A different embodiment of the invention comprises an organic and natural semisolid composition comprising between approximately 0.0001% and approximately 20% oregano oil, and a semisolid natural carrying medium to form a biocide that when applied to a mammal in an effective treatment dose kills mammal parasites. In one embodiment, the natural carrying medium is a gel such as Aloe Vera gel, or petroleum jelly.

Further scope of applicability of the present invention will be set forth in part in the detailed description to follow, taken in conjunction with the accompanying drawings, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The accompanying drawings, which are incorporated into and form a part of the specification, illustrate one or more embodiments of the present invention and, together with the description, serve to explain the principles of the invention. The drawings are only for the purpose of illustrating one or more preferred embodiments of the invention and are not to be construed as limiting the invention. Note, in the Tables 1 and 2 and in FIGS. 1-5, biocide formulations were based on oil from Lippia berlandiere (Mexican Oregano), and in FIGS. 6A and 6B formulations were based on oil from Oreganum vulgare (European Oregano).

FIG. 1 shows the gas chromatography and mass spectrometry analyses of the biocide (top 2 spectra) as compared to a commercial standard of carvacrol (bottom spectrum);

FIG. 2 shows the results of studies demonstrating the antimicrobial effect against the plant pathogen Xanthomonas campestris (the causative agent of Bacterial Spot Disease) using an embodiment of a biocide formulation compared to carvacrol;

FIG. 3A. shows Jalapeno plants with and without symptoms of Bacterial Spot Disease caused by X. campestris;

FIG. 3B shows the incidence and severity of Bacterial Spot Disease on Japapeno. Note the almost complete alleviation of symptoms when plants were treated with 0.1% of an embodiment of the present invention;

FIGS. 4A-D show photographs of agar plates inoculated with the plant pathogen Phytothphera capsici and comprising Mexican oregano oil at different concentrations (A=zero, B=0.1%, C=0.05% and D=0.5%);

FIGS. 5A-D show agar plates inoculated with the plant pathogen Rhizoctonia solani treated with Mexican oregano oil at different concentrations (A=0, B=0.1%, C=0.05%, D=0.5%);

FIGS. 6A-B show the effect of 1% European oregano oil on growth and survival of the nematode, Caenorhabditis elegans after 3 days exposure. FIG. 6A shows the live, motile nematode growing in absence of oil; and in 5B, two non-motile dead nematode in the presence of 1% oil;

FIG. 7 is an agar plate inoculated with a bacterium isolated from a cow with symptoms of mastitis and exposed to varying concentrations of the oil.

FIG. 8A is a photograph of a semisolid, slow-release formulation embodiment; and

FIG. 8B is a photograph of a gel formulation embodiment.

DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the invention. However, it will be understood by one of ordinary skill in the art that the embodiments may be practiced without these specific details. For instance, well known operation or techniques may not be shown in detail. Technical and scientific terms used in this description have the same meaning as commonly understood to one or ordinary skill in the art to which this subject matter belongs.

As used throughout the specification and claims, the term “surfactant” refers to compounds that lower the surface tension of a liquid, the interfacial tension between two liquids, or that act as detergents, wetting agents, emulsifiers, foaming agents, or dispersants. Similarly, solid and gel materials are used to dilute and solidify the essential oil in biocide formulations to control pathogens of plant, animal and human.

As used throughout the specification and claims, the term “emulsion” means a mixture of two or more liquids that are normally immiscible, for example oil and water.

As used throughout the specification and claims, the term “effective concentration” means the concentration of essential oils in aqueous, solid and gel materials used as biocide delivery media.

As used throughout the specification and claims, the term “effective treatment dose” means the quantity of biocide that effectively kills fungi, bacteria, viruses, nematodes, insects, etc., for treatment of infections in plants and animals.

Embodiments and compositions of the present invention comprise organic, natural biocide compositions comprising essential plant oils and combinations thereof delivered as a solid, gel, or liquid. Liquid formulations preferably comprise natural surfactants to emulsify the constituents and increase their effectiveness.

With regard to liquid formulations, the challenge to developing a natural biocide comprising essential oils in water is that generally, when water and oil are mixed together, for example by shaking the mixture, a dispersion of oil droplets is formed in the water. However, when the shaking stops, the phases start to separate. A third substance has to be added to the mixture to maintain the oil droplets dispersed in the water, i.e., a surfactant to act as an emulsifier is added to create a stable emulsion. The emulsifier positions itself at the oil/water interface and, by reducing the surface tension, has a stabilizing effect on the emulsion. A stable emulsion can be applied to crops, for example, by being sprayed more efficiently, and can remain active for a longer period of time since the phases do not readily separate. Alternatively, oil can be applied as solid when mixed with appropriate solidifying agents, or as a topical ointment when formulated using polymeric gels.

Embodiments for formulations disclosed herein use either Mexican or European oregano oil, which have similar effectiveness. In one embodiment of the invention, a composition comprises water and between approximately 0.0001% and approximately 20% of Mexican or European oregano oil, more preferably between approximately 0.0005% and approximately 10% of oregano oil, and most preferably between approximately 0.001% and approximately 5% of oregano oil. Different oil concentration ranges are preferably used for different applications for effective treatment doses, for example, 0.001% to 0.5% for bacterial and weak fungal pathogens; 0.1%-25% for more robust fungal pathogens; 0.1-10% for control of nematodes and insects, etc.

The oil is preferably emulsified in the water through a natural surfactant for a composition that when applied in an effective concentration kills plant pests, including but not limited to, fungi, bacteria, viruses, nematodes, insects, etc. In one embodiment called NMX-1, the natural emulsifier is albumin, at a ratio of between approximately 20 and approximately 5 parts oil to 1 part albumin; more preferably between approximately 15 and approximately 7 parts oil to one part albumin; and most preferably at a ratio of between approximately 12 and approximately 9 parts oil to 1 part albumin. Albumin can alternatively be used as a liquid or as a dry solid.

In another embodiment called NMX-2, a detergent, for example, Tween 20 or Sodium Dodecyl sulfate (SDS), is preferably added to the composition to improve emulsification and stability of the oil. In one embodiment, a composition preferably comprises water, oil, and between approximately 0.0001% and approximately 2% detergent, more preferably between approximately 0.0005% and approximately 1% detergent, and most preferably between approximately 0.001% and approximately 0.1% detergent.

Another embodiment, called NMX-3, of the present invention preferably comprises natural saponins from desert plants, for example, of the genera Yucca as emulsifying agents for the biocidal oil, used in the same proportions as described for albumin in the NMX-1 embodiment above.

In one embodiment, a composition is stored, sold, and distributed more conveniently in a concentrated form that can be diluted with water prior to application on site to be used as a biocide. The final concentrations and ratios of the concentrated product formulations are the same as described above.

In another embodiment, called NMX-4, a solid pellet form is preferably made from a solid, or semisolid carrying medium, such as, but not limited to, grain flours, e.g., wheat, oat, rice, millet, tapioca, and the like. Oregano oil is preferably diluted and “cut” into flours and diluted into final oil concentrations ranging from between approximately 0.001% and approximately 50%, more preferably between approximately 0.01 and approximately 30%, and most preferably between approximately 0.1% and approximately 20%. Preferably, the solid material carrying medium allows the slow release of the oil into the surrounding environment.

In order to make the solid embodiment formulations resistant to crumbling, additives or stabilizers, such as but not limited to, xanthum gum, guar gum, and the like, are preferably incorporated in concentrations ranging from between approximately 0.001% and approximately 50%, more preferably between approximately 0.01 and approximately 30%, and most preferably between approximately 0.1% and approximately 20%. The proportions of xanthum gum are preferably also varied in order to provide variable-release pesticide formulations, with 0.1%-1% xanthum gum giving fast-moderate release of the pesticide in the field, and 1-10% xanthum gum giving moderate to slow-release formulations. Optionally, the mixture comprises some water. FIG. 8A shows an example solid-based, slow-release formulation.

In another embodiment, a composition is formulated for a salve for treatment of animals and/or humans, comprising oregano oil diluted into a gel, such as but not limited to, aloe vera gel, petroleum jelly, and the like. Preferably, concentrations of oil in the gel vary from between approximately 0.001% and approximately 50%, more preferably between approximately 0.01 and approximately 35%, and most preferably between approximately 0.1% and approximately 25%, depending on the various applications. FIG. 8B shows an example aloe vera-based formulation.

In another embodiment, a composition is formulated to apply to animal or human skin by diluting the oil in other oils such as soybean, safflower and olive oils and the like. Preferably, concentrations of the oregano oil in the other vegetable oils vary from between approximately 0.001% and approximately 50%, more preferably between approximately 0.01 and approximately 35%, and most preferably between approximately 0.1% and approximately 25%, depending on the various applications.

INDUSTRIAL APPLICABILITY

The invention is further illustrated by the following non-limiting examples.

Example 1

Referring to FIG. 1, the bioactive agents in Mexican oregano oil were identified by Gas Chromatography/Mass Spectrometry (“GC/MS”). The first two plots represent the two analyses of separate oil preparations and the last plot represents the spectrum of a pure carvacrol standard (Sigma). The most prevalent components in the Mexican oregano oil were identified by GC/MS library analysis to be: 1=cyclohexene-methyl cymene; 2=thymol; 332 carvacrol.

Example 2

When the most well-known biocide component of oregano oil, Carvacrol, was used in compositions of biocides, it was not as effective as the essential oil (see FIG. 2), indicating that there is synergistic effect when these agents work together in combination in the essential oil. In FIG. 2, the growth of X. campestris Provencia strain was assessed under different concentrations of Mexican oregano oil or pure carvacrol (dissolved in methanol solvent). The bars in the graph indicate the bacterial number (CFU) that was reached after 18 hours of incubation. At the same concentration of 0.01 mg/ml, oregano oil was significantly more inhibitory than carvacrol (p-value=0.009) indicating that, at equal concentrations, the biocide is more potent than carvacrol. Thus, a composition of biocide comprising oregano oil exerts synergistic effects, due, in part, to the multiple antimicrobial biochemicals that make up the oil (see FIG. 1).

The seeds of the greenhouse Jalapeno plants were infected with X. campestris, and, without the NMX spray, developed symptoms of bacterial spot disease. At 20 days and 50 days post germination, Jalapeno plants were sprayed with 0.1% NMX-1 oil using a squirt bottle adjusted to give a fine mist spray. The treatment of Jalapeno plants with low concentrations of oregano oil (0.1%) protected plants from Bacterial Spot Disease. In FIG. 3A, the photographs show Jalapeno plants infected with X. campestris, and plants without symptoms.

Referring to FIG. 3B, Jalapeno bacterial spot symptoms were quantified as to incidence and severity. Plants that were not foliar treated exhibited symptoms as shown in A, and plants that were foliar treated with a formulation of biocide comprising oregano oil 1 mg/mL (0.1%) showed little or no symptoms.

Example 3

Referring to FIGS. 4-5, exposure to 0%, 0.05%, 0.1%, and 0.5% concentrations of Mexican oregano oil on agar plates demonstrated that the mycelial growth of P. capsici (FIG. 3D) and R. solani (FIG. 4D) are completely inhibited by oregano oil at a concentration of 0.50%.

Example 4

The essential oil was also found to be effective in controlling nematodes. Referring to FIG. 6, after a 3-day incubation, three of four nematodes survived in the absence of oregano oil, but no nematodes survived (see FIG. 6B) in the presence of a formulation of biocide comprising oregano oil at 0.1% or 1%. After 6 days, there still were no live nematodes in the presence of both concentrations of the oregano oil, but in its absence the nematode populations grew to 75-200 nematatodes.

Example 5

An embodiment of the biocide was found to inhibit bacteria causing cow mastitis. In FIG. 7, an agar plate was inoculated with a bacterium isolated from the milk of a mastitis-infected cow in the presence of discs saturated with varying concentrations of oil. The bacterium grew in the absence of the oil (as demonstrated by the opaque colonial growth on the left), but was inhibited by varying concentrations of the oil.

Example 6

An embodiment of the biocide was found to have broad antimicrobial activities against plant, animal and human pathogens. Table 1 below shows the broad-spectrum antimicrobial effect of an embodiment for a natural biocide, inhibiting (bacteriostatic) or killing (bacteriocidal) bacteria (18 species) and fungi (2 species), including numerous human pathogens. The controls were grown using the same concentration of methanol (0.1%) which was used in the biocide. 20 of 20 test bacteria and fungi were either killed or significantly inhibited by the biocide, including representative plant, animal and human pathogens. The average optical density (O.D. 625 nm) of five replicate growth cultures was calculated, and are expressed as percent of growth relative to a minus-oil control. S=Strong inhibition≦50%, M=Moderate inhibition≦65%, W=Weak inhibition≦75% of control, NE=No effect>75% of growth relative to control. Note: 0.1 mg/mL=0.01% wt. to vol.

	Concentration	Percent of Growth
	of Oil	relative to Control	Inhibitory
Microorganism	(mg/ml)	(sd)	Score
Bacillus cereus	0.1	12.8 ± 0.52	S
	0.01	49.20 ± 3.04	S
	0.001	78.88 ± 0.86	NE
Bacillus megaterium	0.1	23.38 ± 0.23	S
	0.01	84.82 ± 6.48	NE
	0.001	98.35 ± 0.74	NE
Bacillus subtilis	0.1	16.24 ± 0.01	S
	0.01	33.68 ± 0.05	S
	0.001	73.65 ± 0.01	W
Candida krusei	0.1	22.9 ± 1.36	S
	0.01	53.05 ± 2.17	M
	0.001	75.98 ± 1.38	NE
Corynebacterium	0.1	12.47 ± 0.01	S
pseudodiphteriae	0.01	34.70 ± 0.03	S
	0.001	64.77 ± 0.07	M
Geotrichum candidum	0.1	11.41 ± 0.64	S
	0.01	29.89 ± 1.46	S
	0.001	74.80 ± 3.70	W
Micrococcus luteus	0.1	11.16 ± 0.01	S
	0.01	18.91 ± 0.01	S
	0.001	42.72 ± 0.03	S
Streptococcus lactis	0.1	9.16 ± 0.02	S
	0.01	18.67 ± 0.01	S
	0.001	40.82 ± 0.01	S
Streptococcus	0.1	26.64 ± 0.44	S
pyogenes	0.01	45.23 ± 2.10	S
	0.001	113.37 ± 5.83	+
Staphylococcus aureus	0.1	11.43 ± 0.63	S
	0.01	44.97 ± 1.92	S
	0.001	76.05 ± 1.48	W
Alcaligenes faecalis	0.1	5.27 ± 0.01	S
	0.01	25.33 ± 0.05	S
	0.001	50.63 ± 0.02	M
Enterobacter cloacae	0.1	10.21 ± 0.62	S
	0.01	42.17 ± 2.39	S
	0.001	101.21 ± 8.83	+
Escherichia coli	0.1	23.64 ± 4.23	S
	0.01	40.52 ± 6.17	S
	0.001	98.77 ± 0.77	NE
Klebsiella pneumoniae	0.1	38.03 ± 0.07	S
	0.01	49.48 ± 0.03	S
	0.001	78.74 ± 0.01	NE
Neisseria perflava	0.1	10.67 ± 0.03	S
	0.01	38.61 ± 0.02	S
	0.001	84.60 ± 0.14	NE
Pseudomonas	0.1	21.96 ± 0.01	S
aeuruginosa	0.01	70.01 ± 0.06	W
	0.001	106.33 ± 0.33	+
Pseudomonas	0.1	25.07 ± 0.56	S
fluorescens	0.01	69.64 ± 1.96	W
	0.001	98.05 ± 1.15	NE
Proteus vulgaris	0.1	24.87 ± 0.03	S
	0.01	55.19 ± 0.02	M
	0.001	76.83 ± 0.01	NE
Serratia marcescens	0.1	10.89 ± 0.43	S
	0.01	92.19 ± 1.07	+
	0.001	97.54 ± 1.51	+
Shigella flexneri	0.1	22.01 ± 0.63	S
	0.01	79.84 ± 1.42	NE
	0.001	96.84 ± 2.82	NE

Table 2 below shows the bacteriocidal and bacteriostatic effects of formulations of biocide against four strains of a common plant pathogen, Xanthomonas campestris. The dose at which 50% of the X. campestris bacteria were killed by the bioagent (ie., the LD₅₀) ranged between 0.1-0.5%. The causative agent of Bacterial Spot Disease, 4 of 4 strains of the X. campestris was killed or significantly inhibited by the biocide. The average O.D. 625 nm of five replicates was calculated and expressed as percent of growth relative to a minus-oil control. S=Strong inhibition≦50%, M=Moderate inhibition≦65%, W=Weak inhibition≦75% of control, NE=No effect>75% on growth relative to control. Note: 10 mg/mL=1% wt. to vol.

Xanthomonas		Percent of growth
campestris	Concentration of Oil	relative to control +/−	Inhibitory
strain	(mg/ml)	Std Dev	score
Alvarez	10	0 ± 0.43	S
	2	0 ± 0.36	S
	1	6.56 ± 2.2	S
	0.5	27.26 ± 5.9	S
	0.1	59.54 ± 1.4	M
	0.01	74.48 ± 0.62	W
	0.001	88.55 ± 0.5	NE
Provencia	10	0 ± 0.09	S
	2	0.21 ± 0.05	S
	1	5.01 ± 0.28	S
	0.5	6.25 ± 2	S
	0.1	59.57 ± 10.94	M
	0.01	72.13 ± 3.88	W
	0.001	91.63 ± 7.09	NE
Deming	10	0 ± 0.2	S
	2	0 ± 0.02	S
	1	5.96 ± 0.8	S
	0.5	35.10 ± 2.4	S
	0.1	66.06 ± 2.8	W
	0.01	102.62 ± 2.6	NE
	0.001	112.82 ± 0.8	NE
Tula	10	0 ± 0.07	S
	2	0 ± 0.06	S
	1	3.26 ± 0.24	S
	0.5	8.23 ± 0.33	S
	0.1	42.03 ± 4.9	S
	0.01	79.70 ± 3.9	NE
	0.001	96.11 ± 2.03	NE

The preceding examples can be repeated with similar success by substituting the generically or specifically described reactants and/or parameters of this invention for those used in the preceding examples. Note that in the specification and claims, “about” or “approximately” means within twenty percent (20%) of the numerical amount cited.

Although the invention has been described in detail with particular reference to these preferred embodiments, other embodiments can achieve the same results. Variations and modifications of the present invention will be obvious to those skilled in the art and it is intended to cover in the appended claims all such modifications and equivalents. The entire disclosures of all references, applications, patents, and publications cited above are hereby incorporated by reference.

Claims

1. An organic natural composition comprising: between approximately 0.0001% and approximately 20% oregano oil; water; anda natural emulsifier to emulsify said oregano oil in said water and form a pesticide that when applied in an effective treatment dose kills plant pests.

2. The composition of claim 1 wherein said natural emulsifier is albumin at a ratio of between approximately 20 and approximately 5 parts oregano oil to 1 part albumin.

3. The composition of claim 2 comprising between approximately 0.0005% and approximately 10% of oregano oil.

4. The composition of claim 2 comprising between approximately 0.001% and approximately 5% of oregano oil.

5. The composition of claim 2 comprising said albumin at a ratio of between approximately 15 and approximately 7 parts oregano oil to one part albumin.

6. The composition of claim 2 comprising said albumin at a ratio of between approximately 12 and approximately 9 parts oil to 1 part albumin.

7. The composition of claim 1 wherein said natural emulsifier comprises natural saponins extracted from a desert plant.

8. The composition of claim 7 wherein said desert plant is of the genera Yucca.

9. The composition of claim 7 comprising between approximately 0.0005% and approximately 10% of oregano oil.

10. The composition of claim 7 comprising between approximately 0.001% and approximately 5% of oregano oil.

11. An organic natural semisolid composition comprising: between approximately 0.0001% and approximately 20% oregano oil; anda semisolid natural carrying medium to form a pesticide that when applied in an effective treatment dose kills plant pests.

12. The semisolid composition of claim 11 wherein said natural carrying medium is grain based flour selected from the group consisting of wheat, oat, rice, millet, and tapioca flour.

13. The semisolid composition of claim 11 further comprising an additive to prevent crumbling.

14. The semisolid composition of claim 13 wherein said additive is provided at a concentration ranging between approximately 0.001% and approximately 50%.

15. The semisolid composition of claim 14 wherein said additive is at a concentration of between approximately 0.01 and approximately 30%.

16. The semisolid composition of claim 14 wherein said additive is at a concentration of between approximately 0.1% and approximately 20%.

17. The semisolid composition of claim 14 wherein said additive is xanthum gum.

18. The semisolid composition of claim 14 wherein said additive is guar gum.

19. The semisolid composition of claim 11 comprising between approximately 0.01 and approximately 30% oregano oil.

20. The semisolid composition of claim 11 comprising between approximately 0.1% and approximately 20% oregano oil.

21. The composition of claim 1 wherein said natural emulsifier is Tween 20.

22. An organic and natural semisolid composition comprising: between approximately 0.0001% and approximately 20% oregano oil; anda semisolid natural carrying medium to form a biocide that when applied to a mammal in an effective treatment dose kills mammal parasites.

23. The composition of claim 22 wherein said natural carrying agent is a gel.

24. The composition of claim 23 wherein said gel is Aloe Vera gel.

25. The composition of claim 23 wherein said gel is petroleum jelly.