NZ715577B2 - Humidity activated formulation for volatile compounds - Google Patents

Abstract

This invention is related to controlled release formulations of volatile antimicrobial compounds against pathogens affecting meats, plants, or plant parts or dairy products. Provided are delivery systems in the form of coatings or films, where controlled release of their volatile components in vapor form is triggered by high relative humidity. The volatile component may include, for example volatile antimicrobial liquids including low molecular weight alcohols and/or aldehydes, 1 -methylcyclopropene, and/or other volatile fungicides. form is triggered by high relative humidity. The volatile component may include, for example volatile antimicrobial liquids including low molecular weight alcohols and/or aldehydes, 1 -methylcyclopropene, and/or other volatile fungicides.

Description

HUMIDITY ACTIVATED FORMULATION FOR VOLATILE COMPOUNDS OUND OF THE INVENTION Existing commercial approaches for ring volatile antimicrobial oils into a headspace (such as in shoe—boxes) typically involve an absorbent pad, tissue or film which is charged with the volatile oil (by soaking it or exposing it to an here of the volatile oil) and stored in air-tight packaging before use. One major disadvantage with this approach is that as soon as the pad / tissue / film is removed from its air-tight packaging, as there is little control over the release rate, it may lose a large amount / all of the volatile oil before the e of the le oil into the headspace is desired. For example, to use in a supply chain for packaging freshly harvested berries, the material after removal from air-tight packaging, may be exposed to ambient conditions, followed by forced air cooling for several hours, during which time no appreciable release of volatile oil is desired.

Alternative approaches may involve casting coatings from solvents which n the dissolved volatile oil and a hydrophobic binder. One major disadvantage with this approach is that most of the volatile oil typically escapes from the coating during the drying process, and during storage.

Additional approaches involve the use of yclodextrin (beta-CD) to encapsulate the volatile oil within a coating. One major disadvantage with D is its poor solubility in common casting solvents ding water), and its high molecular weight (Mw = 1135) relative to the molecular weight of a typical volatile oil. Due to its high molecular weight, a relatively large mass of beta—CD needs to be used to encapsulate the le oil, resulting in high expense and relatively low levels of volatile oil orated into the coating.

Thus, there remains a need to develop effective material with controlled release of volatile compounds, in particular for agricultural applications.

Y OF THE INVENTION This invention is related to controlled release formulations of volatile antimicrobial compounds t pathogens affecting meats, plants, or plant parts or dairy products. Provided are delivery systems in the form of coatings or films, where controlled release of their volatile components in vapor form is triggered by high relative humidity. The volatile component may include, for example volatile antimicrobial liquids including low molecular weight alcohols and/or des, l-methylcyclopropene, and/or other volatile fungicides.

In one aspect, provided is a controlled release formulation or humidity-activated material comprising (a) a binder component; and (b) a volatile component dispersed in the binder component.

In one embodiment, the binder component comprises polyvinyl l. In another embodiment, the binder component does not comprise ose, starch, gum, or polyethylene glycol (polyethylene oxide).

In one embodiment, the volatile component comprises an antimicrobial nd. In a further embodiment, the antimicrobial compound comprises a volatile fungicide. In another embodiment, the volatile component ses a volatile oil. In a further embodiment, the volatile oil comprises extracts from an sm selection from the group consisting llea spp., Amomum spp., Asteraceae spp., Borago spp., Brassica spp., Bulnesia spp., Calamus spp., Camellia spp., Cananga spp., um spp., Cassia spp., Cedrus spp., Chamaecyparis spp., Chrysopogon spp., Cinnamomum spp., Citrus spp., Coriandrum spp., Cupressus spp., Curcuma spp., Cymbopogon spp., Diantlzus spp., szterocarpus spp., Elettaria spp., Eucalyptus spp., F0rniculum spp., Gaultlzeria spp., Geranium spp., Glycine spp., Gossypium spp., Iris spp., Jasminear spp., Juniperus spp., Lavandula spp., Linum spp., Lippia spp., Litsea spp., Melaleuca spp., Mentha spp., Myristica spp., Ocimum spp., zera spp., Origanum spp., Pimenta spp., Pimpinella spp., Pinus spp., Piper spp., emon spp., Ricinus spp., Rosa spp., Rosmarinus spp., Salvia spp., Santalum spp., Sassafras spp., Secale spp., Sesamum spp., Simmondsia spp., Syringa spp., Syzygium spp., Thuja spp., Thymus spp., Trigonella spp., Vanilla spp., Zea spp., Zingiber spp., and combinations thereof.

In another embodiment, the volatile component does not comprise a substance (for example a gas) with boiling point below zero degree Celsius (0 0C), for example C02, C102 or $02. In a further embodiment, the volatile component does not comprise C102 or $02. In another embodiment, the the volatile component has a boiling point between 40 0C and 300 0C. In another embodiment, the volatile component has a boiling point between 100 0C and 300 0C. In another embodiment, the volatile ent comprises solid or liquid precursors to the volatile nds (gasses). In r embodiment, the volatile component comprises a volatile compound or a lar complex of a volatile compound and a molecular encapsulating agent.

In one embodiment, the antimicrobial compound is against a pathogen selected from the group consisting ofAcremoniam spp., Albago spp., Alternaria spp., Ascochyta spp., Aspergillas spp., diplodia spp., Botryospheria spp., Botrjytis spp., Byssochlamys spp., Candida spp., Cephalosporiam spp., Ceratocystis spp., Cercospora spp., Chalara spp., Cladosporiam spp., Colletotricham spp., Cryptosporiopsis spp., Cylindrocarpon spp., Debarjyomyces spp., Diaporthe spp., Didymella spp., Diplodia spp., Dothiorella spp., Elsinoe spp., Fasariam spp., cham spp., poriam spp., Glomerella spp., Helminthosporiam spp., Khaskia spp., iplodia spp., Macrophoma spp., Macrophomina spp., Microdochiam spp., Monilinia spp., Monilochaethes spp., Macor spp., Mycocentrospora spp., Mycosphaerella spp., Nectria spp., Neofabraea spp., Nigrospora spp., Penicilliam spp., Peronophythora spp., Peronospora spp., Pestalotiopsis spp., Pezicala spp., Phacidiopycnis spp., Phoma spp., Phomopsis spp., Phyllosticta spp., Phytophthora spp., Polyscytalam spp., Pseudocercospora spp., Pyricalaria spp., m spp., Rhizoctonia spp., Rhizopas spp., Sclerotiam spp., Sclerotinia spp., Septoria spp., Sphaceloma spp., Sphaeropsis spp., ylliam spp., Stilbella spp., Thielaviopsis spp., Thyronectria spp., Trachysphaera spp., Uromyces spp., Ustilago spp., Venturia spp., and Verticilliam spp. In another embodiment, the pathogen is selected from the group consisting of Bacillus spp., Campylobacter spp., Clavibacter spp., Clostridiam spp., Erwinia spp., Escherichia spp., Lactobacillas spp., Leaconostoc spp., Listeria spp., Pantoea spp., Pectobacteriam spp., Pseudomonas spp., Ralstonia spp., Salmonella spp., Shigella spp., Staphylococcus spp., Vibrio spp., Xanthomonas spp., and Yersinia spp. In another embodiment, the en is selected from the group consisting of Cryptosporidiam spp. and Giardia spp.

In another embodiment, the package material is for use for meats, plants, plant parts, and/or dairy products. In a further embodiment, the plants or plant parts se transgenic plants or enic plant parts. In another embodiment, the plants or plant parts are selected from the group ting of barley, camphor tree, canola, castor-oil plant, cinnamon, cocoa, coffee, corn, cotton, flax, grapevine, hemp, hops, jute, maize, mustard, nuts, oat, poppy, rape, rice, rubber plant, rye, sunflower, sorghum, soybean, sugar cane, tea, tobacco, and wheat. In another ment, the plants or plant parts are selected from the group consisting of fruit, vegetables, nursery, turf and ornamental crops. In a further embodiment, the fruit is ed from the group consisting of almond, apple, avocado, , berries ding strawberry, blueberry, raspberry, blackberry, currents and other types of berries), ola, cherry, citrus (including oranges, lemon, lime, mandarin, grapefruit, and other citrus), coconut, fig, grapes, guava, kiwifruit, mango, nectarine, melons (including cantaloupe, muskmelon, watermelon, and other melons), olive, papaya, passionfruit, peach, pear, mon, pineapple, plum, and pomegranate. In a further embodiment, the ble is selected from the group consisting of asparagus, beet (including sugar and fodder beet), beans, broccoli, cabbage, carrot, cassava, cauliflower, celery, cucumber, eggplant, garlic, n, leafy greens (lettuce, kale, spinach, and other leafy greens), leek, lentils, mushroom, onion, peas, pepper (sweet, bell or hot), potato, pumpkin, sweet potato, snap bean, squash, tomato and turnip. In a further ment, the nursery plant or flower or flower part is selected from the group ting of roses, carnation, geranium, gerbera, lily, orchid, or other cut—flowers or ornamental flowers, flower bulbs, shrub, deciduous or coniferous tree. In a further embodiment, the meat is selected from the group of beef, bison, chicken, deer, goat, turkey, pork, sheep, fish, shellfish, mollusks, or dry— cured meat products.

In another embodiment, the volatile compound comprises a cyclopropene compound of the formula: [>‘R wherein R is a substituted or unsubstituted alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkylalkyl, , or naphthyl group; wherein the substituents are independently halogen, alkoxy, or substituted or unsubstituted phenoxy.

In a further ment, R is C1_g alkyl. In another embodiment, R is methyl. In another embodiment, the volatile compound comprises a cyclopropene compound of the formula: R3 R4 R1‘ ‘RZ wherein R1 is a substituted or unsubstituted C1—C4 alkyl, C1—C4 alkenyl, C1—C4 alkynyl, C1—C4 cylcoalkyl, cylcoalkylalkyl, phenyl, or napthyl group; and R2, R3, and R4 are hydrogen.

In another embodiment, the volatile compound comprises 1—methylcyclopropene (l—MCP). In a r embodiment, the e material ses between 0.01% and %; between 0.1% and 10%; n 0.3% and 3%; or between 10% and 25% of 1—MCP.

In another embodiment, the molecular ulating agent is selected from the group consisting of alpha-cyclodextrin, beta-cyclodextrin, gamma-cyclodextrin, or combinations thereof In another embodiment, the molecular encapsulating agent comprises alpha-cyclodextrin or beta-cyclodextrin. In a further ment, the molecular encapsulating agent comprises beta-cyclodextrin. In another embodiment, the le component is not substantially released below 30% relative humidity after a period of five (5) hours, but is released between 60% and 100%; between 75% and 100%; or between 80% and 90% relative humidity at room temperature.

In r aspect, provided is a method for preparing the controlled release material. The method comprises (a) dispersing the volatile component in an aqueous solution or dispersion of a binder component to form a mixture; and (b) casting the mixture onto a package material. In another embodiment, the mixture may be cast onto a substrate to give a coated sheet which may be inserted into, onto, beneath, or adjacent to a packaging material.

In r embodiment, the coating may be peeled off the coated sheet to give a film which may be inserted into, onto, beneath, or nt to a packaging material.

In one embodiment, no radiation is used. In another embodiment, the binder component comprises polyvinyl alcohol. In another embodiment, the binder component does not comprise cellulose, starch, gum, polyethylene oxide, or polyethylene glycol.

In one embodiment, the volatile component comprises an antimicrobial compound. In a further ment, the crobial compound comprises a volatile fungicide. In another embodiment, the volatile component comprises a volatile oil. In a further embodiment, the volatile oil comprises extracts from an organism ion from the group ting ofAchillea spp., Amomum spp., ceae spp., Borago spp., Brassica spp., Bulnesia spp., Calamus spp., Camellia spp., Cananga spp., Capsicum spp., Cassia spp., Cedrus spp., cyparis spp., Chrysopogon spp., Cinnam0mum spp., Citrus spp., drum spp., sus spp., Curcuma spp., Cymb0p0g0n spp., Dianthus spp., Dipterocarpus spp., Elettaria spp., Eucalyptus spp., F0rniculum spp., Gaultheria spp., Geranium spp., Glycine spp., Gossypium spp., Iris spp., ear spp., Juniperus spp., Lavandula spp., Linum spp., Lippia spp., Litsea spp., Melaleuca spp., Mentha spp., Myristica spp., Ocimum spp., Ornothera spp., um spp., Pimenta spp., Pimpinella spp., Pinus spp., Piper spp., P0g0stem0n spp., Ricinus spp., Rosa spp., R0smarinus spp., Salvia spp., Santalum spp., Sassafras spp., Secale spp., Sesamum spp., Simmondsia spp., Syringa spp., Syzygium spp., Thuja spp., Thymus spp., Trigonella spp., Vanilla spp., Zea spp., Zingiber spp., and ations thereof.

In another embodiment, the volatile component does not comprise a substance (for example a gas) with g point below zero degree Celsius (0 0C), for example C02, C102 or $02. In a further embodiment, the volatile component does not comprise C102 or $02. In another ment, the the volatile component has a g point between 40 0C and 300 0C. In another embodiment, the volatile ent has a boiling point between 100 0C and 300 0C. In another embodiment, the volatile component comprises solid or liquid precursors to the volatile nds (gasses). In another embodiment, the volatile component comprises a volatile compound or a lar complex of a volatile compound and a molecular encapsulating agent.

In one embodiment, the antimicrobial compound is against a pathogen selected from the group ting ofAcremonium spp., Albugo spp., Alternaria spp., Ascochyta spp., Aspergillus spp., Botryodiplodia spp., Botrjyospheria spp., Botrjytis spp., Byssochlamys spp., Candida spp., Cephalosporium spp., Ceratocystis spp., pora spp., Chalara spp., Cladosporium spp., Colletotrichum spp., Cryptosporiopsis spp., Cylindrocarpon spp., Debaryomyces spp., Diaporthe spp., Didymella spp., Diplodia spp., rella spp., e spp., Fusarium spp., Geotrichum spp., Gloeosporium spp., Glomerella spp., Helminthosporium spp., Khuskia spp., Lasiodiplodia spp., Macrophoma spp., Macrophomina spp., Microdochium spp., Monilinia spp., Monilochaethes spp., Mucor spp., Mycocentrospora spp., Mycosphaerella spp., Nectria spp., Neofabraea spp., Nigrospora spp., Penicillium spp., Peronophythora spp., Peronospora spp., Pestalotiopsis spp., Pezicula spp., Phacidiopycnis spp., Phoma spp., Phomopsis spp., Phyllosticta spp., Phytophthora spp., Polyscytalum spp., Pseudocercospora spp., laria spp., Pythium spp., Rhizoctonia spp., Rhizopus spp., Sclerotium spp., Sclerotinia spp., Septoria spp., Sphaceloma spp., Sphaeropsis spp., Stemphyllium spp., Stilbella spp., Thielaviopsis spp., Thyronectria spp., Trachysphaera spp., Uromyces spp., Ustilago spp., Venturia spp., and Verticillium spp. In r embodiment, the pathogen is selected from the group consisting of Bacillus spp., Campylobacter spp., Clavibacter spp., Clostridium spp., Erwinia spp., ichia spp., acillus spp., Leuconostoc spp., Listeria spp., Pantoea spp., Pectobacterium spp., Pseudomonas spp., Ralstonia spp., Salmonella spp., la spp., Staphylococcus spp., Vibrio spp., Xanthomonas spp., and Yersinia spp. In another embodiment, the pathogen is selected from the group consisting of Cryptosporidium spp. and a spp.

In another embodiment, the material is for use for meats, plants, plant parts, and/or dairy products. In a further embodiment, the plants or plant parts comprise transgenic plants or transgenic plant parts. In another embodiment, the plants or plant parts are selected from the group consisting of barley, camphor tree, canola, castor-oil plant, cinnamon, cocoa, coffee, corn, cotton, flax, grapevine, hemp, hops, jute, maize, mustard, nuts, oat, poppy, rape, rice, rubber plant, rye, er, sorghum, soybean, sugar cane, tea, tobacco, and wheat. In another embodiment, the plants or plant parts are selected from the group consisting of fruit, vegetables, nursery, turf and ornamental crops. In a r embodiment, the fruit is selected from the group consisting of almond, apple, avocado, banana, berries (including strawberry, blueberry, rry, blackberry, currents and other types of berries), carambola, cherry, citrus (including oranges, lemon, lime, mandarin, grapefruit, and other ), coconut, flg, grapes, guava, uit, mango, nectarine, melons (including cantaloupe, muskmelon, watermelon, and other melons), olive, , passionfruit, peach, pear, persimmon, pineapple, plum, and anate. In a further embodiment, the vegetable is selected from the group ting of asparagus, beet (including sugar and fodder beet), beans, li, cabbage, carrot, cassava, cauliflower, , cucumber, eggplant, garlic, gherkin, leafy greens (lettuce, kale, spinach, and other leafy greens), leek, lentils, mushroom, onion, peas, pepper (sweet, bell or hot), potato, pumpkin, sweet potato, snap bean, squash, tomato and turnip. In a further embodiment, the nursery plant or flower or flower part is selected from the group consisting of roses, carnation, geranium, gerbera, lily, orchid, or other cut-flowers or ornamental flowers, flower bulbs, shrub, deciduous or coniferous tree. In a further ment, the meat is ed from the group of beef, bison, chicken, deer, goat, turkey, pork, sheep, flsh, shellfish, mollusks, or dry—cured meat products.

In another embodiment, the volatile compound comprises a cyclopropene compound of the formula: I>——R wherein R is a substituted or unsubstituted alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkylalkyl, phenyl, or naphthyl group; wherein the substituents are independently n, alkoxy, or substituted or unsubstituted phenoxy.

In a further embodiment, R is C1_g alkyl. In r embodiment, R is methyl. In another embodiment, the volatile compound comprises a cyclopropene compound of the formula: R3 R4 R1‘ ‘R2 wherein R1 is a substituted or unsubstituted C1—C4 alkyl, C1—C4 alkenyl, C1—C4 alkynyl, C1—C4 cylcoalkyl, cylcoalkylalkyl, phenyl, or napthyl group; and R2, R3, and R4 are hydrogen.

In r embodiment, the volatile compound comprises l—methylcyclopropene (1—MCP). In a r embodiment, the package material comprises between 0.1% and 10%; between 0.3% and 3%; or n 0.01% and 1% ofthe 1—MCP.

In another embodiment, the molecular encapsulating agent is ed from the group consisting of alpha-cyclodextrin, beta-cyclodextrin, gamma-cyclodextrin, or combinations thereof. In another embodiment, the molecular encapsulating agent comprises alpha-cyclodextrin or beta-cyclodextrin. In a further embodiment, the molecular encapsulating agent comprises beta-cyclodextrin. In another embodiment, the volatile component is not substantially released below 30% relative humidity after five (5) hours, but is released between 60% and 100%; between 75% and 100%; or between 80% and 100% relative humidity at room temperature.

In some embodiments, the mixture has a viscosity greater than 100 cPs (centipoise); or greater than 500 cPs. In other ment, the mixture has a viscosity between 100 and 50,000 cPs; between 250 and 30,000 cPs; n 500 and 30,000 cPs; or between 500 and 50,000 cPs.

In another aspect, provided is a method for preparing the material provided herein.

The method comprises (a) dispersing the volatile component in an s solution or dispersion of a binder component; (b) casting the mixture onto a solid substrate; and (c) solidifying the mixture to generate a coating on the solid substrate.

In one embodiment, no radiation is used. In another embodiment, the solidifying step comprises drying with heat. In a further embodiment, the heat is applied at a temperature between 10 °C and 120 0C; between 15 °C and 100 0C; or between 20 °C and 110 0C. In another embodiment, the heat is applied at a temperature between 40 0C and 120 0C; between 60 °C and 100 0C; or between 80 0C and 110 0C.

In another embodiment, the solidifying step comprises drying with a stream of gas (for example air). In a further embodiment, the stream of gas is applied at a temperature between 10 °C and 120 0C; between 15 0C and 100 0C; or between 20 0C and 110 0C. In another ment, the stream of gas is applied at a temperature between 40 0C and 120 0C; n 60 °C and 100 0C; or between 80 0C and 110 0C.

In some embodiments, the mixture has a ity r than 100 cPs (centipoise); or greater than 500 cPs. In other embodiment, the mixture has a viscosity n 100 and 50,000 cPs; n 250 and 30,000 cPs; between 500 and 30,000 cPs; or n 500 and 50,000 cPs.

In some embodiments, the mixture has a viscosity greater than 90 cPs; greater than 100 cPs; greater than 250 cPs; or r than 500 cPs. In other embodiment, the mixture has a viscosity n 50 and 2,000 cPs; n 90 and 100 cPs; or n 250 and 1,000 cPs.

In another aspect, provided is a method for preparing the material provided herein.

The method comprises (a) preparing a first liquid comprising the ; (b) mixing the first liquid with the volatile component to generate a mixture; (c) casting the mixture onto a solid substrate; and (d) solidifying the mixture to te the package material.

In one embodiment, no radiation is used. In another embodiment, the solidifying step ses drying with heat. In a further embodiment, the heat is applied at a temperature between 10 °C and 120 0C; between 15 °C and 100 0C; or between 20 °C and 110 0C. In another embodiment, the heat is applied at a temperature between 40 0C and 120 0C; between 60 °C and 100 0C; or between 80 0C and 110 0C.

In another embodiment, the solidifying step comprises drying with a stream of gas (for e air). In a r embodiment, the stream of gas is applied at a temperature between 10 °C and 120 0C; between 15 0C and 100 0C; or between 20 0C and 110 0C. In another embodiment, the stream of gas is applied at a temperature between 40 0C and 120 0C; between 60 °C and 100 0C; or between 80 0C and 110 0C.

In some embodiments, the mixture has a ity greater than 100 cPs (centipoise); or r than 500 cPs. In other embodiment, the mixture has a viscosity between 100 and 50,000 cPs; between 250 and 30,000 cPs; between 500 and 30,000 cPs; or between 500 and 50,000 cPs.

In some embodiments, the mixture has a ity greater than 90 cPs; greater than 100 cPs; greater than 250 cPs; or greater than 500 cPs. In other embodiment, the mixture has a viscosity between 50 and 2,000 cPs; between 90 and 100 cPs; or between 250 and 1,000 cPs.

In another aspect, provided is a material which is in the form of a coating on a packaging material. In another aspect, provided is a material which is in the form of a sheet which is inserted into, onto, beneath, or adjacent to a packaging material. In another aspect, provided is a material which is in the form of a label which is adhered onto a packaging material. In another aspect, provided is a method of applying the material provided herein.

The method comprises (a) inserting fresh produce into a package; (b) inserting the coated substrate, film, sheet, or label into, onto, beneath, or adjacent to the package; and (c) sealing or enclosing the package, thereby the material is exposed to high relative humidity generated by the fresh e.

DETAILED DESCRIPTION OF THE ION The controlled release formulation / material / delivery system provided herein may include a volatile (liquid) component ulated within a film or coating. In one embodiment, the film or coating has the following advantages: (1) retaining / encapsulating the volatile (liquid) component under dry conditions or conditions of te relative ty (even when heated), and (2) releasing the volatile d) component (in vapor form) on re to high relative humidity or moisture.

The controlled e ation / material / delivery system in the form of a coating or film provided herein uses a binder which is a good barrier to organic gasses at low / moderate relative humidity, resulting in little / no diffusion of the le component (for example volatile oil) out of the coating or film under typical ambient conditions. The high relative humidity inside fruit, vegetable, ntal flower, meat, or cheese packaging (typically 90 %+) is used as a trigger to release the volatile component (for example volatile oil). The rate of release at high humidity can be adjusted by adjustment of the coating formulation.

The embodiments provided provide the advantage to avoid substantial loss of the volatile component (for example volatile oil) during the drying process by use of a binder which is a good barrier to organic gasses at low / te relative humidity. In one embodiment, during the drying process, a skin (or top surface) is first formed on the surface of the coating. The skin (or top surface) is impermeable to the volatile component (for example volatile oil), but permeable to water vapor. Hence the remainder of the water evaporates from the coating but the volatile component (for example volatile oil) remains trapped inside.

Suitable compounds for the volatile component include aliphatic or aromatic compounds, including their acids, alcohols, aldehydes, esters, and ketones. In another embodiment, the nd is a monoterpenoid or aliphatic ure up to 12 carbons in length. In a further embodiment, the compound is selected from the group consisting of allyl disulfide, allyl sulfide, amyl cinnamic aldehyde, (x-phellandrene, amyl cinnamic aldehyde, amyl salicylate, anethole, trans-anethole, anisic aldehyde, p—anisaldehyde, benzaldehyde, benzyl acetate, benzyl alcohol, bergamot, bicyclogermacrene, borneol, bornyl acetate, 2- butene, (x—butylene, nene, calamenene, (x-campholenic aldehyde, camphor, X- caryophyllene, hyllene oxide, caryophyllene, carvacrol, carveol, 4— 2014/046312 carvomenthenol, carvone, cineole, 1,4-cineole, 1,8-cineole, cinnamaldehyde, hexyl- cinnamaldehyde, trans-cinnamaldehyde, cinnamic alcohol, (x-cinnamic terpinene, (x-isoamyl- cinnamic, cinnamyl alcohol, citral, citric acid, citronella and oil, ellal, hydroxy citronellal, citronellol, (x-citronellol, citronellyl acetate, citronellyl nitrile, corn gluten meal, coumarin, cuminaldehyde, p—cymene, decanal, trans—Z—decenal, decyl aldehyde, diethyl ate, dihydroanethole, dihydrocarveol, dihydrocarvone, dihydrolinalool, dihydromyrcene, dihydromyrcenol, dihydromyrcenyl e, dihydroterpineol, dill, dimethyl salicylate, cis—3,7—dimethyl—l,6-octadien-3yl acetate, cis-3,7-dimethyl-2,6-octadien-l-ol, dimethyloctanal, dimethyloctanol, dimethyloctanyl acetate, yl salicylate, dimethyl thiophene, diphenyl oxide, dipropylene glycol, dodecanal, estragole, ethyl vanillin, eucalyptol, l, eugenyl acetate, farnesol, fenchol, femiol, furfural, galaxolide, geraniol, geranyl acetate, geranyl nitrile, globulol, guaiacol, gurjunene, heliotropin, herbanate, l- hexanol, hexanal, trans-Z-hexen-l-al, ulene, hydrogen de, ionone, isoamyl isovalerate, isobutyl quinoleine, isobornyl acetate, isobornyl methylether, isobutyric anhydride, isoeugenol, isolongifolene, isosafrole, isothiocyanate, jasmonic acid, lauryl sulfate, lavandin, ne, linalool oxide, linalool, linalyl acetate, longifolene, malic acid, menthe, ne hydroperoxide, menthol, menthyl acetate, menthofurane, menthol , menthone, methional, methyl acetate, methyl anthranilate, methyl cedryl ketone, methyl chaVicol, methyl cinnamate, methyl cyclopropane, methyl eugenol, methyl hexyl ether, methyl ionone, methyl ate, l-methylisopropyl-l-cyclohexenol, methyl salicylate, 3-methyl thiopropionaldehyde, muscone, musk xylol, myrcene, neral, nerol, neryl acetate, nonyl de, trans-B-ocimene, palustrol, perillaldehyde, petitgrain, (x-phellandrene, phydroxy phenyl butanone, phenyl ethyl alcohol, phenyl ethyl propionate, phenyl 2- methylbutyrate, cis-pinane, pinane hydroperoxide, pinanol, pine ester, ene, (x-pinene oxide, B-pinene, piperonal, piperonyl acetate, piperonyl alcohol, , plinyl acetate, potassium sorbate, 2-propanol, 2-propenyl methyl disulphide, l-proponyl methyl disulphide, pseudoionone, pulegone, ol, rhodinyl acetate, rosalin, rinic acid, safrole, salicylaldehyde, sandenol, sodium chloride, sodium lauryl sulfate, sotolon, spathulenol, spirantol, terpenoid, terpineol, (x-terpineol, terpineol, (x-terpinene, X-terpinene, terpinolene, terpinyl acetate, tert-butylcyclohexyl acetate, tetrahydrolinalool, tetrahydrolinalyl acetate, tetrahydromyrcenol, (x,[3—thujone, , turpentine, undecanoic acid, lO—undecenoic acid, vanillin, and verbenone.

Unless otherwise , the following terms used in this application, including the specification and claims, have the definitions given below. It must be noted that, as used in the specification and the appended claims, the singular forms CC 3’ (C a an” and “the” include plural referents unless the context clearly dictates otherwise. Definition of standard chemistry terms may be found in reference works, including Carey and Sundberg, Advanced Organic Chemistry 4th Ed., Vols. A (2000) and B (2001), Plenum Press, New York, NY.

The term “composition,” as used herein, includes a mixture of als which comprise the composition, as well as reaction products and decomposition products formed from the materials of the composition.

Embodiments ed herein may include one or more polymer(s) listed herein.

The term “humidity-activated,” as used herein, refers to that the volatile component is released as a vapor on exposure of the material to high humidity. In one embodiment, high humidity includes 75 % to 100% ve humidity. In another embodiment, high humidity includes 60 % to 100% relative humidity.

The term “polymer,” as used herein, refers to a polymeric compound prepared by polymerizing monomers, whether of the same or a different type. The generic term r thus es the term homopolymer (employed to refer to polymers prepared from only one type of monomer, with the understanding that trace s of impurities can be orated into the r structure), and the term interpolymer.

The term “functionalized polymer,” as used herein, refers to a polymer that comprises, linked by a covalent bond, a chemical group (chemical substituent) comprising at least one heteroatom. A heteroatom is defined as an atom which is not carbon or en.

Common heteroatoms are oxygen, nitrogen, sulfur, and phosphorus.

The term “functional group,” as used herein, refers to a chemical substituent containing at least one heteroatom. A heteroatom is defined as an atom which is not carbon or hydrogen. Common heteroatoms include oxygen, nitrogen, sulfur, and phosphorus.

The term “perishable material,” as used herein, refers to organic matter which can spoil or decay, or which has a decrease in activity of one or more of its active components over time.

The terms ising,” “including,” “having,” and their derivatives, are not intended to exclude the presence of any additional component, step or ure, whether or not the same is ically disclosed. In order to avoid any doubt, all compositions claimed through use of the term “comprising” may include any additional additive, adjuvant, or compound, r ric or ise, unless stated to the contrary. In contrast, the term, “consisting ially of ’ excludes from the scope of any succeeding recitation any other component, step or procedure, excepting those that are not essential to operability. The term “consisting of’ excludes any component, step or procedure not specifically delineated or listed.

The practice of the present invention may involve the use of one or more cyclopropene compounds. As used herein, a cyclopropene nd is any nd with the formula R3 R4 Where each R1, R2, R3 and R4 is independently selected from the group consisting of H and a chemical group of the a: '(L)n'z Where n is an integer from 0 to 12. Each L is a bivalent radical. Suitable L groups include, for e, radicals ning one or more atoms selected from H, B, C, N, O, P, S, Si, or mixtures thereof. The atoms Within an L group may be connected to each other by single bonds, double bonds, triple bonds, or mixtures thereof. Each L group may be linear, branched, cyclic, or a combination f. In any one R group (i.e., any one of R1, R2, R3 and R4) the total number of heteroatoms (i.e., atoms that are neither H nor C) is from 0 to 6.

Independently, in any one R group the total number of non—hydrogen atoms is 50 or less.

Each Z is a monovalent radical. Each Z is independently selected from the group ting of hydrogen, halo, cyano, nitro, nitroso, azido, chlorate, bromate, iodate, isocyanato, isocyanido, ocyanato, pentafluorothio, and a chemical group G, wherein G is a 3 to 14 ed ring system.

The R1, R2, R3, and R4 groups are independently selected from the suitable groups.

Among the groups that are suitable for use as one or more of R1, R2, R3, and R4 are, for example, aliphatic groups, aliphatic-oxy , alkylphosphonato groups, cycloaliphatic groups, cycloalkylsulfonyl groups, cycloalkylamino groups, heterocyclic groups, aryl groups, heteroaryl groups, halogens, silyl groups, other groups, and mixtures and combinations thereof. Groups that are suitable for use as one or more of R1, R2, R3, and R4 may be substituted or unsubstituted.

Among the suitable R1, R2, R3, and R4 groups are, for example, aliphatic groups.

Some suitable aliphatic groups include, for example, alkyl, alkenyl, and alkynyl groups.

Suitable aliphatic groups may be linear, branched, cyclic, or a combination thereof.

Independently, suitable aliphatic groups may be substituted or unsubstituted.

As used herein, a chemical group of interest is said to be ituted” if one or more hydrogen atoms of the chemical group of interest is replaced by a tuent.

Also among the suitable R1, R2, R3, and R4 groups are, for example, substituted and unsubstituted heterocyclyl groups that are connected to the cyclopropene compound through an intervening oxy group, amino group, yl group, or sulfonyl group; examples of such R1, R2, R3, and R4 groups are heterocyclyloxy, heterocyclylcarbonyl, diheterocyclylamino, and diheterocyclylaminosulfonyl.

Also among the le R1, R2, R3, and R4 groups are, for example, substituted and unsubstituted cyclic groups that are connected to the cyclopropene compound through an intervening oxy group, amino group, carbonyl group, sulfonyl group, thioalkyl group, or aminosulfonyl group; examples of such R1, R2, R3, and R4 groups are diheteroarylamino, heteroarylthioalkyl, and diheteroarylaminosulfonyl.

Also among the suitable R1, R2, R3, and R4 groups are, for e, en, fluoro, chloro, bromo, iodo, cyano, nitro, nitroso, azido, chlorato, bromato, iodato, isocyanato, isocyanido, isothiocyanato, pentafluorothio; acetoxy, carboethoxy, cyanato, nitrato, nitrito, perchlorato, allenyl, ercapto, diethylphosphonato, ylphenylsilyl, isoquinolyl, mercapto, naphthyl, phenoxy, phenyl, piperidino, pyridyl, quinolyl, triethylsilyl, trimethylsilyl; and substituted analogs thereof.

As used herein, the chemical group G is a 3 to 14 membered ring system. Ring systems suitable as chemical group G may be substituted or unsubstituted; they may be aromatic (including, for e, phenyl and napthyl) or aliphatic (including unsaturated aliphatic, partially saturated aliphatic, or saturated tic); and they may be carbocyclic or heterocyclic. Among heterocyclic G groups, some le heteroatoms are, for e, nitrogen, sulfur, oxygen, and combinations thereof. Ring systems suitable as chemical group G may be monocyclic, bicyclic, tricyclic, polycyclic, spiro, or fused; among suitable chemical group G ring systems that are bicyclic, tricyclic, or fused, the various rings in a single chemical group G may be all the same type or may be of two or more types (for example, an aromatic ring may be fused with an aliphatic ring).

In one ment, one or more of R1, R2, R3, and R4 is hydrogen C10) alkyl. In another embodiment, each of R1, R2, R3, and R4 is hydrogen or (C1-C8) alkyl. In another embodiment, each of R1, R2, R3, and R4 is hydrogen or ) alkyl. In another ment, each of R1, R2, R3, and R4 is hydrogen or methyl. In another embodiment, R1 is (C1-C4) alkyl and each of R2, R3, and R4 is hydrogen. In another embodiment, R1 is methyl and each of R2, R3, and R4 is en, and the cyclopropene compound is known herein as ylcyclopropene or “l—MCP.” In another embodiment, the cyclopropene is of the formula: [>‘R wherein R is a substituted or unsubstituted alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkylalkyl, phenyl, or naphthyl group; wherein the substituents are independently halogen, alkoxy, or substituted or unsubstituted phenoxy. In one embodiment, R is C1_g alkyl.

In another embodiment, R is methyl.

In another embodiment, the cyclopropene is of the formula: R3 R4 R1” ‘RZ wherein R1 is a substituted or unsubstituted C1—C4 alkyl, C1—C4 alkenyl, C1—C4 alkynyl, C1—C4 cylcoalkyl, cylcoalkylalkyl, phenyl, or napthyl group; and R2, R3, and R4 are hydrogen. In another embodiment, the ropene comprises l—methylcyclopropene (l—MCP).

As used herein, the phrase “transgene vector” refers to a vector that contains an inserted segment of DNA, the “transgene” that is transcribed into mRNA or replicated as RNA within a host cell. The phrase “transgene” refers not only to that n of inserted DNA that is converted into RNA, but also those portions of the vector that are necessary for the transcription or replication of the RNA. A transgene typically comprises a gene—of— st but needs not necessarily comprise a polynucleotide sequence that contains an open reading frame capable of producing a protein.

Meats, plants, or plant parts, or dairy ts may be treated in the practice of the present invention. One example is treatment of whole plants; r e is treatment of whole plants while they are planted in soil, prior to the ting of useful plant parts.

Any plants that provide useful plant parts may be treated in the practice of the present invention. Examples include plants that provide fruits, vegetables, nursery crops, flowers and grains.

As used herein, the phrase “plant” es dicotyledons plants and monocotyledons plants. Examples of dicotyledons plants include tobacco, Arabidopsis, soybean, tomato, papaya, canola, sunflower, cotton, alfalfa, potato, grapevine, pigeon pea, pea, Brassica, chickpea, sugar beet, rapeseed, watermelon, melon, pepper, peanut, pumpkin, radish, spinach, squash, li, e, carrot, cauliflower, celery, Chinese cabbage, cucumber, eggplant, and lettuce. Examples of monocotyledons plants include com, rice, wheat, sugarcane, , rye, sorghum, orchids, bamboo, banana, cattails, lilies, oat, onion, millet, and ale. Examples of fruit include apple, avocado, banana, berries (including strawberry, blueberry, raspberry, blackberry, currents and other types of berries), carambola, cherry, citrus (including oranges, lemon, lime, mandarin, grapefruit, and other citrus), coconut, flg, grapes, guava, kiwifruit, mango, nectarine, melons (including cantaloupe, muskmelon, watermelon, and other melons), olive, papaya, passionfruit, peach, pear, persimmon, pineapple, plum, and pomegranate. Examples of ble include asparagus, beet (including sugar and fodder beet), beans, broccoli, cabbage, carrot, a, cauliflower, celery, cucumber, eggplant, , gherkin, leafy greens (lettuce, kale, spinach, and other leafy greens), leek, lentils, mushroom, onion, peas, pepper (sweet, bell or hot), potato, pumpkin, sweet potato, snap bean, squash, tomato and turnip. Examples of nursery plant or flower or flower part include roses, carnation, geranium, gerbera, lily, orchid, or other cut- flowers or ornamental , flower bulbs, shrub, deciduous or rous tree Various embodiments provided are based on dispersion of the volatile (liquid) component in a binder which is a good barrier to c gasses under conditions of low / moderate relative humidity, but a poor barrier to organic gasses under ions of high relative humidity.

In one embodiment, the volatile (liquid) component comprises an essential oil / natural oil / plant extract with antimicrobial properties. In another embodiment, the film/ coating provided herein can be inserted inside packaging for fruit, vegetable, flower, or other plant parts, meat or cheese, to control mold or bacterial growth. Various volatile essential oils / natural oils / plant extracts red to orth as “volatile oils”) are known to delay the onset of mold growth and are currently used commercially in packaging applications.

Suitable binders include water—soluble or water—dispersible s for example polyvinyl alcohol (PVOH), where polyvinyl alcohol refers to fully or partially hydrolyzed polyvinyl acetate, polyvinylpyrrolidone, polyvinylpyridine, polyvinylimidazole , polyvinylcaprolactam, polyethylene glycol, polypropylene , onalized cellulose such as cellulose containing methoxy functions, or hydroxyethyl or hydroxypropyl ons, polyhydroxyethyl(meth)acrylate, polyethyleneimine, polyethylene-co-acrylic acid or salts thereof, poly(meth)acrylic acid or salts f, polystyrene sulfonic acid or salts thereof, polyethylene-co-vinyl alcohol (EVOH), or gums for example acacia gum. Copolymers of these polymers with other monomeric units may be suitable binders as well.

A suitable binder for various embodiments provided herein includes polyvinyl alcohol, as it is a good barrier to organic gasses when dry and a poor barrier when exposed to high relative humidity. In one embodiment, polyvinyl alcohol is used with a hydrolysis degree between 55% and 100%; or between 65% and 99%. le volatile oils for s embodiments provided herein include non—water— soluble liquid substances which can form (with optional aid of a sant) a stable on in an aqueous solution of the binder.

As used herein, a fluid is “non—aqueous” if it contains, by weight based on the weight of the fluid, 10 % water or less. As used herein, a liquid that has high viscosity is a composition that is liquid at 25°C and that has viscosity at 25 0C at shear rate of 0.01 sec'1 of Pa * s (10 Poise) or more.

The solution provided may have a viscosity of from about 100 to about 50,000 centiPoise; or 500 to 30,000 centiPoise. Below the preferred viscosity, the dispersed oil droplets are thought to migrate y to the surface of the coating while drying and hence escape to the atmosphere during the drying process. In another preferred embodiment, the coating is dried under a stream of gas, preferably air, in order to rapidly form an eable skin on the surface of the g.

Various embodiments provided herein are in the form of a sheet (coated substrate or free-standing film) or a label, which is inserted into a package or a pallet, or a coating on the inside or outside surface of the packaging material. The package can be a small consumer—size package, a bulk bag, a box, or a pallet wrap.

Those skilled in the art would understand certain variation can exist based on the disclosure provided. Thus, the ing examples are given for the purpose of illustrating the invention and shall not be construed as being a limitation on the scope of the invention or claims.

EXAMPLES Example 1 25 grams polyvinyl alcohol l 4—88, degree of hydrolysis 88%) is dissolved in 75 grams deionized water under stirring and gentle warming, to generate solution Al, which is d to cool to ambient. 0.042 gram sodium dodecyl sulphate is dissolved in 3.57 grams deionized water, and 8.33 grams 1-hexanol is added drop-wise while stirring y with a magnetic stirrer to generate emulsion B1. The white emulsion B1 is added to solution A1 and then shaken to produce a white mixture C1, where e C1 has a viscosity of about 983 cPs (shear rate = 2.31 s'l). The amount of 1-hexanol relative to the total amount of [PVOH + 1-hexanol] is % by weight.

The white e C1 is cast onto a PET substrate at a wet thickness of 254 microns, and then dried to produce Formulation D1.

Table 1. Headspace analysis of Formulation D1 (25% PVOH, high viscosity).

Formulation Drying conditions %RH in Area of film ppm nol in D 1 vial strip (cmz) 20mL headspace Sample 1 -1 Ambient, 16 hours Ambient* 16 0 (comparative) 100% 15.3 2 Sample 1-2 Cool air stream 15 Ambient* 14.3 0 minutes, then ambient 16 hours 15.4 592 nt %RH is 49% when the GC s are prepared The dried [PVOH/1—hexanol/sds] coatings on PET are cut into strips of approximately 15 cm2 and then the coatings are peeled off the PET strips and the delaminated coating strips placed in an oven at 80 0C for 15 minutes in order to remove any remaining non-encapsulated 1-hexanol.

The strips of coating are then placed inside GC headspace vials (20 mL). In some cases a droplet of water (0.10 mL) is added to the bottom of the vial (avoiding contact with the strip) before the vial is sealed, in order to generate an atmosphere of 100% relative humidity (RH). The vials are then allowed to equilibrate for at least 10 hours before placing in an Agilent GC for analysis of the tration of 1-hexanol in the headspace. A vial containing pure 1—hexanol (0.50 mL) is used as reference. The reference vial is assumed to create a saturated concentration of 1224 ppm of 1-hexanol in the headspace (calculated from known vapor pressure of 0.124 kPa at 25 0C).

The concentrations of 1—hexanol detected in the headspaces of the vials from ation D1 are shown in Table 1. It can be seen that the sample which is dried under a stream of air and also exposed to 100% humidity releases a significant amount of 1-hexanol into the headspace.

Example 2 15 grams polyvinyl alcohol (Mowiol 4—88, degree of hydrolysis 88%) is dissolved in 85 grams deionized water under stirring and gentle warming, to generate solution A2, which is allowed to cool to ambient.

Table 2. Headspace is of Formulation D2 (15% PVOH, low ity). ation Drying ions %RH in Area of film ppm 1-hexanol in D2 vial strip (cmz) 20mL headspace Sample 2-1 Ambient, 16 hours Ambient* 15.1 0 (comparative) Sample 2-2 Cool air stream 15 Ambient* (comparative) s, then ambient 16 hours 100% *Ambient %RH is 49% when the GC samples are prepared 0.025 grams sodium dodecyl sulphate is dissolved in 2.14 grams zed water, and 5 grams 1-hexanol is added drop-wise while ng rapidly with a magnetic stirrer to generate emulsion B2. The white emulsion B2 is added to solution A2 and then shaken to produce a white mixture C2, where mixture C2 has a viscosity of about 94 cPs (shear rate = 26.4 s'l). The amount of 1-hexanol relative to the total amount of [PVOH + 1-hexanol] is % by weight.

The white mixture C2 is cast onto a PET substrate at a wet thickness of 254 microns, and dried according to produce Formulation D2.

A similar headspace analysis as in Example 1 is performed, and 1-hexanol detected in the headspaces of the vials from ation D2 are shown in Table 2.

Results from Examples 1 and 2 indicate that a combination of relatively high viscosity coating on and drying under a stream of air is needed in order to encapsulate the 1-hexanol inside the PVOH film. In addition, 1-hexanol is not released under ambient relative humidity, but significant amounts are released at about or close to 100% relative humidity at ambient temperature (20—25 0C).

Example 3 A mixture C3 is made and cast onto a PET substrate to produce Formulation D3 [PVOH/1-hexanol/sds] in a similar manner as in Example 1, except a stronger air-stream was used for drying the coatings than in Examples 1 and 2. The dried coating on PET is cut into strips of approximately 7 cm2 and then the coating is peeled off each strip and placed in an oven at 80 °C for 15 minutes in order to remove any non-encapsulated 1-hexanol. The delaminated strips of coating are then placed inside GC headspace vials. The GC headspace vials contained small vessels containing different saturated salt solutions (about 0.15 mL) in order to control the relative humidity inside the GC vials. The theoretical relative humidities generated by the saturated aqueous salt ons at 20 °C are shown in Table 3. The salts used to generate the different relative humidities are: LiCl gives 11% RH; MgClz gives 33% RH; K2CO3 gives 43% RH; )2 gives 54% RH; NaBr gives 58% RH (at 25 °C); KI gives 69% RH (at 25°C); NaCl gives 76% RH; and K2S04 gives 98% RH. The vials are left to stand at 20 °C for 13-17 hours, and then the concentration of 1-hexanol in the headspace is ed by Agilent GC. Mixture C3 also has a viscosity of about 983 cPs.

Table 3. Headspace analysis for Formulation D3 (25% PVOH, high viscosity).

Drying Conditions % RH in GC Area of film ppm 1-hexanol in 20 mL vial (20°C) strip (cmz) headspace after 13—17 hours Cool air stream 15 11% 6.9 11 $3231? 115 6'79 59 54% 6.9 5 87 58% (25°C) 6.9 1055 69% (25°C) 6.9 1143 76% 6.9 1128 98% 6.86 1062 A vial containing pure 1—hexanol (0.50 mL) is used as nce. The reference vial is d to create a saturated concentration of 1224 ppm of 1-hexanol in the headspace (calculated from known vapor pressure of 0.124 kPa at 25 °C). The concentrations of 1- hexanol found in the headspaces of the vials for Formulation D3 are shown in Table 3.

The results show that after 13-17 hours, greater amounts of 1-hexanol have been released corresponding to increasing s of relative humidity inside the GC headspace vials at ambient temperature (20—25 °C).

Example 4 A mixture C4 is made and cast onto a PET substrate to produce Formulation D3 2014/046312 [PVOH/1-hexanol/sds] in a r manner as in Example 1, except a er air-stream was used for drying the coatings than in Examples 1 and 2. The dried g on PET is cut into strips of approximately 7 cm2 and then the coating is peeled off each strip and placed in an oven at 80 0C for 15 minutes in order to remove any non-encapsulated 1-hexanol. The nated strips of coating are then placed inside GC headspace vials. The GC headspace vials contained small vessels containing saturated aqueous solutions of KNO3 (about 1.5 mL) which theoretically generated an atmosphere of 95% relative humidity inside the vials. At different intervals after sealing the strip of coating inside the GC vial, headspace samples are injected into the Agilent GC for analysis of concentration of 1-hexanol.

Table 4. Headspace analysis for Formulation D4 (25% PVOH, high viscosity).

Drying ions Time elapsed after Area of film ppm 1-hexanol in 20 sealing GC vial (hrs) strip (cmz) mL headspace Cool air stream 15 0.15 6.49 54 minPteSa the“ 0.63 6.6 278 amb1ent 16 hours 1. 18 6.75 650 1.73 6.6 863 2.25 6.79 961 2.78 6.9 964 3.3 3 6.9 1043 4.43 6.75 1057 8. 82 7.05 1098 A vial containing pure 1—hexanol (0.50 mL) is used as reference. The nce vial was assumed to create a saturated concentration of 1224 ppm of 1-hexanol in the headspace (calculated from known vapor pressure of 0.124 kPa at 25 OC). The results of headspace analysis are shown in Table 4, indicating the rapid rate of release of 1-hexanol from the delaminated strip of coating at a relative humidity of 95% at t temperature (20—25 0C). Mixture C4 also has a viscosity of about 983 cPs (shear rate = 2.31 s'l).

Example 5 Comparison of l-Hexanol, trans-Z-hexenal, and Guaiacol Preparation of PVOH Emulsions containing 1-Hexanol, transhexenal, or guaiacol: 35.0 g Poly vinyl alcohol (PVOH, Mowiol 4—88) is added to a glass beaker and then 65.0 g d de—ionized (DI) water is added. The mixture is heated to 60—80 °C and stirred with a mechanical stirrer until the PVOH is fully dissolved. Aluminum foil is used to cover the beaker to reduce ation during heating — the beaker is weighed before heating and after dissolution of the PVOH, and additional DI water is added to replace any water lost due to evaporation. 0.05 83g sodium dodecyl sulfate (SDS) is added into 5.0g DI water. The mixture is d on a magnetic stirrer until the SDS is dissolved. To the solution of SDS in water is added 11.667 g 1—hexanol, trans—Z—hexenal, or guaiacol (the “actives”) drop—wise, under rapid stirring to form a white emulsion (70 weight % 1-hexanol, trans-Z-hexenal, or guaiacol in water). The resultant emulsion is then added to the cooled solution of PVOH in the beaker and the resultant mixture stirred mechanically for 5 minutes. In the case of 1-hexanol, and trans-Z-hexenal, the resultant homogeneous white emulsion is allowed to stand for approximately hours to allow bubbles to dissipate before casting. In the case of guaiacol, a transparent solution is obtained.

Casting of ons: Using an Elcometer 4340 film ator with a Gardco Microm II film 9” casting blade, the [PVOH/ 1-hexanol / SDS / water] emulsion, the [PVOH / trans—Z—hexenal / SDS / water] emulsion, or the [PVOH / guaiacol / SDS / water] solution, is cast onto a PET sheet. A wet thickness of 10 mils (254 microns) is used. Immediately after casting, the coating is dried using a commercial hair-dryer directed at an angle of approximately 450 to the plane of the coating, on low-speed, cool setting, for 15 minutes.

The coating is then left on a drying rack in the fume-hood overnight.

Table 5. Quantification of compounds using GC analysis Active % Incorporated active (compared Absolute amount of active Compound to theoretical maximum amount) incorporated (wt. %) 1-Hexanol 75.0% 18.8% Trans—Z—hexenal 71.9% 18.0% Guaiacol 68.7% 17.2% Quantification of Amount of 1-hexanol, trans-Z-hexenal or ol in Coating: A strip of approximately 6.8cm2 is cut from the middle of the coated PET sheet. The coating is peeled off the PET backer and then placed in a petri-dish in a fume-hood ght to allow any al non-encapsulated active to evaporate. The following day, the delaminated coating is precisely weighed into a 20 mL GC vial. 5.0 grams of DI water is added, and the vial immediately sealed. The contents of the vial are gently swirled to dissolve the coating in the water, and at least 10 hours are allowed for the headspace to equilibrate with the aqueous phase. A ace sample is then removed by e for injection into the GC column.

Quantification of active is done by comparing to a calibration curve of “GC Peak Area of Headspace sample” vs. “Concentration of nol, 2—hexenal, or guaiacol in solution” generated with samples of known concentrations of active compound dissolved in DI water in GC vials (after leaving at least 10 hours for equilibration).

Results are shown in Table 5. oration of 1—hexanol, trans—2—hexenal, and guaiacol is shown as a percentage ve to the maximum theoretical incorporation based on the amount added to the coating solution, assuming no losses due to evaporation (25 wt. % of active), where it can be seen from the data that the PVOH based strips contain high levels of incorporated volatile liquid.

Table 6. Release kinetics of transhexenal.

Time elapsed (hours) after strip Concentration of trans inserted into GC vial at room hexenal in headspace (ppm) temperature / 95%RH 0.17 350.60 0.70 589.45 1.25 1266.50 1.78 2036.63 2.33 5 2.87 4541.25 3.42 6173.40 4.52 7357.28 17.77 6742.25 Analysis of Release of transhexenal or guaiacol from Coating into Headspace: A strip of approximately 2 is cut from the middle of the coated PET sheet. The coating is peeled off the PET backer and then placed in a petri-dish in a fume-hood overnight to allow any residual non-encapsulated active to evaporate. A GC vial, 20 mL, with a screw— on septum—cap is prepared at 95 % ty by adding a mini plastic entrifuge vial with the cap cut off containing approximately 0.20 g of saturated potassium nitrate (KNO3) solution, with a few grains of solid KNO3 added to maintain saturation. After allowing time (at least 2 hours) for the humidity in the vial to equilibrate, the strip of coating is added to the GC vial, and the vial immediately sealed. After allowing the d amount of time for release of the active from the g, a headspace sample is removed by syringe for ion into the GC . The concentration in the Headspace is determined by comparing the GC Peak Area of the sample to the GC Peak Area of the headspace from a vial containing 0.5 mL of pure trans—2—hexenal, or guaiacol. The known vapor pressures of these compounds at room temperature can be used to calculate the saturated headspace concentration for these reference samples (8685, and 145 ppm (V/V) respectively).

Results for trans—2—hexenal are shown in Table 6, and results for guaiacol are shown in Table 7. It can be seen from the data that the strips containing transhexenal, and guaiacol, rapidly release the active compound to achieve headspace saturation levels in the GC vial on exposure to 95 % relative humidity.

Table 7. Release kinetics of guaiacol.

Time d (hours) after strip Concentration of ol in inserted into GC vial at room headspace (ppm) temperature / 95%RH 0.62 1.75 3.52 23.75 1003291517

Claims (21)

We claim :

1. A humidity-activated material in a form of a coating or film comprising: (a) a binder component; and (b) a volatile component dispersed in the binder component; wherein the le ent has a g point between 40 °C and 300 °C; wherein the volatile component is not substantially released below 30% relative humidity, but is released between 60% and 100% relative humidity at room temperature; wherein the binder component comprises polyvinyl alcohol; and wherein the volatile component does not comprise an encapsulating agent.

2. The material of claim 1, wherein the binder component does not comprise cellulose, starch, gum, or polyethylene glycol.

3. The material of claim 1, wherein the volatile component comprises an antimicrobial

4. The material of claim 1, wherein the le component comprises a volatile oil.

5. The material of claim 1, wherein the volatile component comprises a volatile compound.

6. The material of claim 1, wherein the volatile component is not ntially released below 30% ve ty, but is released n 75% and 100% relative humidity at room temperature.

7. The material of claim 1, wherein the volatile component has a boiling point between 100°C and 300°C.

8. The material of claim 1, wherein the volatile component comprises guaiacol.

9. The material of claim 1, wherein the volatile component comprises an antimicrobial compound against a pathogen selected from the group consisting of Achillea spp., 1003291517 Amomum spp., Asteraceae spp., Borago spp., Brassica spp., Bulnesia spp., Calamus spp., Camellia spp., a spp., um spp., Cassia spp., Cedrus spp., Chamaecyparis spp., Chrysopogon spp., Cinnamomum spp., Citrus spp., Coriandrum spp., Cupressus spp., Curcuma spp., Cymbopogon spp., Dianthus spp., Dipterocarpus spp., Elettaria spp., Eucalyptus spp., Forniculum spp., Gaultheria spp., Geranium spp., Glycine spp., Gossypium spp., Iris spp., Jasminear spp., Juniperus spp., Lavandula spp., Linum spp., Lippia spp., Litsea spp., Melaleuca spp., Mentha spp., Myristica spp., Ocimum spp., era spp., Origanum spp., Pimenta spp., ella spp., Pinus spp., Piper spp., Pogostemon spp., Ricinus spp., Rosa spp., Rosmarinus spp., Salvia spp., Santalum spp., Sassafras spp., Secale spp., Sesamum spp., Simmondsia spp., Syringa spp., Syzygium spp., Thuja spp., Thymus spp., ella spp., Vanilla spp., Zea spp., Zingiber spp., and combinations thereof.

10. A method for preparing the material of any one of claims 1-9, comprising: (a) dispersing the le component in an aqueous solution or dispersion of a binder component to give a mixture; (b) casting the mixture onto a packaging material; and (c) solidifying the mixture to generate a coating on the packaging material.

11. A method for preparing the material of any one of claims 1-9, comprising: (a) dispersing the volatile component in an aqueous solution or dispersion of a binder component; (b) g the mixture onto a solid substrate; and (c) solidifying the mixture to generate a coating on the solid substrate.

12. The method of claim 11, wherein the solidifying step ses drying with a stream of gas.

13. The method of claim 12, wherein the stream of gas is applied at a temperature between 20 oC and 120 oC.

14. A method for preparing the material of any one of claims 1-9, sing: (a) sing the volatile component in an aqueous solution or dispersion of a binder component; 1003443239 (b) casting the mixture onto a solid substrate; (c) solidifying the mixture to generate a coating on the solid substrate; and (d) peeling the coating off the solid substrate to te a film or sheet.

15. The method of any one of claims 10, 11 or 14, wherein the e has a ity greater than 90 cPs.

16. The method of any one of claims 10, 11 or 14, wherein the mixture has a viscosity greater than 500 cPs.

17. The method of any one of claims 10, 11 or 14, wherein the mixture has a viscosity between 500 and 50,000 centiPoise.

18. A material according to any one of claims 1-9, which is in the form of a coating on a packaging material.

19. A material according to any one of claims 1-9, which is in the form of a sheet which is inserted into, onto, beneath, or adjacent to a packaging material.

20. A material according to any one of claims 1-9, which is in the form of a label which is adhered onto a packaging material.

21. A method of ng the material of any one of claims 1-9, sing (a) inserting fresh produce into a package; (b) inserting the coating or film onto, beneath, or adjacent to the package; and (c) g or enclosing the package, thereby the material is exposed to high relative humidity generated by the fresh produce.