Applications of microencapsulated essential oils

1. A method for the preparation of a microencapsulated essential oil formulation being in the form of a suspension of microcapsules in an aqueous medium, wherein each microcapsule comprises at least one essential oil, said method comprising:

(a) admixing at least one alkanoic acid with a water-immiscible liquid, wherein said water-immiscible liquid comprises at least one essential oil, thereby obtaining a water-immiscible mixture;

(b) admixing the water-immiscible mixture of step (a) with an aqueous basic solution to obtain a suspension; and

(c) admixing into the suspension of step (b) an aqueous salt solution comprising at least one multivalent cation, thereby obtaining a microencapsulated essential oil formulation, being in the form of a suspension of microcapsules in an aqueous medium, each microcapsule comprising said at least one essential oil.

2. The method according to claim 1, wherein said microencapsulated essential oil formulation contains a plurality of microcapsules, each having a core containing at least one essential oil and an outer shell surrounding said core.

3. The method according to claim 1, wherein said water-immiscible liquid is an essential oil.

4. The method according to claim 1, wherein said aqueous basic solution is an aqueous solution of at least one of sodium hydroxide or potassium hydroxide.

5. A method for the preparation of a microencapsulated essential oil formulation being in a solid form, whereas said formulation comprises a dispersion of microcapsules in a nonvolatile solid vehicle, such that each microcapsule comprises at least one essential oil, said method comprising:

(a) admixing at least one alkanoic acid and at least one essential oil with at least one absorbent thereby obtaining a solid mixture;

(b) optionally admixing at least one additive with said absorbent and said solid mixture;

(c) exposing the solid mixture of any of steps (a) or (b) to an aqueous solution comprising at least one multivalent cation, thereby obtaining a microencapsulated essential oil formulation, being in a solid form whereas said formulation comprises a dispersion of microcapsules in a nonvolatile solid vehicle, such that each microcapsule comprises at least one essential oil.

6. The method according to claim 1, wherein said multivalent cation is a Group II metal cation or a cation of an atom selected from Ca, Mg, Fe, and Al.

7. The method according to claim 1, wherein said alkanoic acid has a melting point temperature higher than 25° C. and/or is selected amongst aliphatic acids having a carbon chain of between 10 and 45 carbon atoms.

8. The method according to claim 7, wherein said alkanoic acid is selected from decanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid, octadecanoic acid, eicosanoic acid, docosanoic acid, tetracosanoic acid, 11-octadecenoic acid, 5,8,11,14-eicosatetraenoic acid, and omega-3 fatty acids, wherein said omega-3 fatty acid is selected from [alpha]-linolenic acid (18:3-omega-3), octadecatetraenoic acid (18:4-omega-3), eicosapentaenoic acid (20:5-omega-3), docosahexaenoic acid (22:6-omega-3), docosapentaenoic acid (22:5-omega-3), eicosatetraenoic acid (20:4-omega-3), uncosapentaenoic acid (21:5-omega-3), docosapentaenoic acid (22:5-omega-3) and any derivative or mixture thereof.

9. The method of claim 1 wherein at least one of said essential oils is an antimicrobial essential oil, thereby obtaining an antimicrobial microencapsulated essential oil formulation.

10. The method of claim 1 wherein at least one of said essential oils is an insect repelling essential oil and/or an insecticide essential oil, thereby obtaining an insect repellent microencapsulated essential oil formulation or an insecticide microencapsulated essential oil formulation.

11. The method of claim 1, wherein said at least one alkanoic acid, said water-immiscible liquid, said at least one essential oil, said aqueous basic solution and said aqueous salt solution are edible, thereby obtaining an edible microencapsulated essential oil formulation.

12. The method according to claim 1, further comprising adding a vehicle and/or a barrier-forming agent and/or at least one absorbent and/or at least one ionic or non-ionic surfactant and/or at least one additive selected from active pharmaceutical agents, natural or synthetic antioxidants, food supplements, insect growth regulators (IGR), insecticides, acaracides, fungicides, nematicides, ectoparasiticides, vitamins, colorants, odorants, oils, fats, flavors, nonvolatile natural oils, dispersants, surfactants, steric barrier polymers and emulsifiers.

13. The method of claim 12, wherein said additive is encapsulated with said at least one essential oil, or is encapsulated separately from said at least one essential oil or is not encapsulated.

14. The method of claim 12, comprising encapsulating at least one volatile essential oil and adding to said formulation at least one nonvolatile oil, which is either encapsulated separately from said volatile essential oil or is non-encapsulated in said formulation.

15. A microencapsulated essential oil formulation, wherein said formulation is in the form of a suspension of microcapsules, each microcapsule comprising at least one essential oil, said suspension being prepared according to the method of claim 1.

16. A microcapsule having an amphiphatic shell surrounding a core comprising at least one essential oil, wherein said amphiphatic shell is a multivalent salt form of at least one alkanoic acid.

17. A microcapsule having a core comprising at least one essential oil, said microcapsule being prepared according to a method comprising:

(I) obtaining a microencapsulated essential oil formulation, being in the form of a suspension of microcapsules in an aqueous media according to claim 1;

(II) isolating and collecting said microcapsules from said aqueous media, and

(III) optionally adding an absorbent capable of absorbing any unencapsulated oil present therein,

thereby obtaining microcapsules comprising at least one essential oil.

18. A microencapsulated essential oil formulation comprising a plurality of the microcapsules of claim 17, wherein the core of each microcapsule is substantially surrounded by an amphiphatic shell.

19. The formulation according to claim 18, wherein said amphiphatic shell is constructed of at least one amphiphile, said amphiphile being an alkanoic acid.

20. The formulation according to claim 15, further comprising a vehicle and/or a barrier-forming agent and/or at least one absorbent and/or at least one ionic or non-ionic surfactant, and/or at least one additive selected from active pharmaceutical agents, natural or synthetic antioxidants, food supplements, insect growth regulators (IGR), insecticides, acaracides, fungicides, nematicides, and/or ectoparasiticides, vitamins, colorants, odorants, oils, fats, flavors, nonvolatile natural oils, dispersants, surfactants, steric barrier polymers and emulsifiers.

21. The formulation of claim 20, wherein said additive is encapsulated with said at least one essential oil, or is encapsulated separately from said at least one essential oil or is not encapsulated.

22. The formulation of claim 20, wherein said additive is an insecticide or an insect growth regulator (IGR) which is encapsulated with said at least one essential oil.

23. The formulation of claim 22, wherein said insecticide or said insect growth regulator (IGR) is selected from pyriproxyphen, azadirachtin and novaluron.

24. The formulation of claim 23, wherein said at least one essential oil is an encapsulated volatile essential oil, further comprising a nonvolatile oil, which is either encapsulated separately from said volatile essential oil or is non-encapsulated.

25. The formulation of claim 20, wherein said nonvolatile natural oils are essential oils or botanical oils.

26. The formulation of claim 25, wherein said nonvolatile natural oil is pyrethrum.

27. The formulation according to claim 15 being a pharmaceutical formulation and/or an antimicrobial formulation and/or an antiseptic formulation.

28. The formulation of claim 27 being an antimicrobial formulation, wherein at least one of said essential oils is an antimicrobial essential oil.

29. The formulation according to claim 28 being useful for the treatment, prevention or control of at least one pathogen selected from Escherichia coli, Staphylococcus Aureus, Micrococcus CNS, Streptococcus Dysgalactiae, Areanobacterium Pyrogenes, and Pseudomonas Aeruginos.

30. A method of treating, preventing or controlling at least one pathogen selected from Escherichia coli, Staphylococcus Aureus, Micrococcus CNS, Streptococcus Dysgalactiae, Areanobacterium Pyrogenes, and Pseudomonas Aeruginos, said method comprising applying the formulation of claim 28 on a surface, an object, an animal or a human subject.

31. The formulation according to claim 15 being an insect repellent formulation or an insecticide formulation, wherein at least one of said essential oils is an insect repellent essential oil or an insecticide essential oil.

32. The formulation according to claim 31 being suitable for direct application onto the skin of animals or humans.

33. A method for repelling, exterminating or managing an insect population, said method comprising applying to an insect environment or to an insect population in said environment, or to the loci thereof, or to the skin of animals or humans, a microencapsulated essential oil formulation prepared according to the method of claim 1 or a microencapsulated essential oil formulation prepared by interfacial polymerization.

34. A method for repelling, exterminating or managing an insect population, said method comprising applying to an insect environment, or to an insect population in said environment, or to the loci thereof, or to the skin of animals or humans, a microencapsulated essential oil formulation, wherein said formulation comprises at least one encapsulated volatile essential oil and at least one non-volatile vehicle in which said at least one volatile essential oil is carried.

35. The method according to claim 34, wherein said formulation is prepared by interfacial polymerization.

36. The method according to claim 34, wherein said non-volatile vehicle is selected from the group of non-volatile essential oils, non-volatile botanical oils or any combination thereof.

37. A method for repelling, exterminating or managing an insect population, said method comprising:

applying to an insect environment, or to an insect population in said environment, or to the loci thereof, or to the skin of animals or humans a microencapsulated essential oil formulation comprising at least one volatile essential oil, and

further applying to said insect environment, or to said insect population in said environment, or to said loci thereof a second formulation comprising a non-volatile agent.

38. The method according to claim 37, wherein said formulation comprising said at least one volatile essential oil or said formulation comprising said non-volatile agent, is prepared by interfacial polymerization.

39. The method of claim 33, wherein said formulation is prepared in an interfacial polymerization process by:

(I) dissolving a diisocyanate or a polyisocyanate within a cold mixture of said essential oils;

(II) optionally dissolving at least one additive in said cold mixture of said essential oils;

(III) dispersing the mixture obtained in steps (I) or (II) in a cold aqueous solution containing diamines or polyamines and/or polyalcohols, thereby encapsulating said essential oils and said additives in a microencapsulated core.

40. The method of claim 33, wherein said formulation is prepared in an interfacial polymerization process by:

(I) dissolving a diisocyanate or a polyisocyanate within at least one essential oil;

(II) admixing said at least one diisocyanate or said polyisocyanate dissolved within at least one essential oil with at least one absorbent, thereby obtaining a solid mixture;

(III) optionally admixing at least one additive with said absorbent and said solid mixture;

(IV) exposing the solid mixture of any of steps (II) or (III) to an aqueous solution or an organic solution, wherein said solution comprises diamines or polyamines, and/or polyalcohols an/or water, thereby obtaining a microencapsulated essential oil formulation, being in a solid form whereas said formulation comprises a dispersion of microcapsules in a solid vehicle, such that each microcapsule comprises at least one essential oil.

41. The method of claim 33, wherein said insect is selected from insects capable of causing annoyance or injury to animals or humans.

42. The method according to claim 41, wherein said insect is selected from mosquitoes, ticks, flies, ants and cockroaches.

43. The formulation according to claim 15 being a food additive formulation for use by humans and/or by animals.

44. The formulation of claim 43, further wherein said at least one alkanoic acid, said water-immiscible liquid, said at least one essential oil, said aqueous basic solution and said aqueous salt solution are edible.

45. The formulation according to claim 43 further comprising at least one oil selected from animal oils, fish oils, vegetable oils, mineral oils, derivatives thereof or mixtures thereof and/or at least one agent selected from a carotenoid, a satiety agent, a flavor compound, and a drug.

46. The formulation according to claim 43 wherein said microcapsules are dissolved or dispersed in a foodstuff.

47. The formulation according to claim 46, wherein said foodstuff is selected from a baked good, a pasta, a meat product, a frozen dairy product, a milk product, a cheese product, an egg product, a condiment, a soup mix, a snack food, a nut product, a plant protein product, a hard candy, a soft candy, a poultry product, a processed fruit juice, a granulated sugar, a sauce, a gravy, a syrup, a nutritional bar, a beverage, a dry beverage powder, a jam or jelly, a fish product, and a pet companion food.

48. A method of preventing or delaying spoilage or discoloration of a foodstuff, wherein said spoilage or discoloration are caused by microorganisms, said method comprising adding into the foodstuff a formulation according to claim 47.

49. The method according to claim 48, wherein said spoilage or discoloration is associated with one or more microorganism selected from Listeria monocytogenes; Salmonella enteriditis; Staphylococcus aureus and vancomycin-resistant Enterococcus.

50. A method according to claim 1, wherein said essential oil is selected from peppermint oil, clove oil, eucalyptus oil and lavender oil; anise essential oil, angelica essential oil, iris essential oil, fennel essential oil, orange essential oil, cananga essential oil, caraway essential oil, cardamom essential oil, guaiacwood essential oil, cumin essential oil, Lindera essential oil, cinnamon essential oil, geranium essential oil, copaiba balsam essential oil, coriander essential oil, perilla essential oil, cedarwood essential oil, citronella essential oil, jasmine essential oil, palmarosa sofia essential oil, cedar essential oil, spearmint essential oil, Western mint essential oil, star anis essential oil, tuberose essential oil, clove essential oil, Neroli essential oil, wintergreen essential oil, tolu balsam essential oil, patchouli essential oil, rose essential oil, palmarosa essential oil, Chamaecyparis obtusa essential oil, Hiba essential oil, sandalwood essential oil, petitgrain essential oil, bay essential oil, vetivert essential oil, bergamot essential oil, Peru balsam essential oil, bois de rose essential oil, ho camphor essential oil, mandarin essential oil, eucalyptus essential oil, lime essential oil, lavender essential oil, linaloe essential oil, lemongrass essential oil, lemon essential oil, rosemary essential oil, Japanese mint essential oil and/or a spice plant essential oil.

51. A method according to claim 5, wherein said absorbent is selected from Celluloses, starch powders, and Aerosil silicas, clays, zeolites, atapulgite, and other inorganic minerals.