Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61Q—SPECIFIC USE OF COSMETICS OR SIMILAR TOILETRY PREPARATIONS
  • A61Q17/00—Barrier preparations; Preparations brought into direct contact with the skin for affording protection against external influences, e.g. sunlight, X-rays or other harmful rays, corrosive materials, bacteria or insect stings
• • A—HUMAN NECESSITIES
  • A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
  • A23B—PRESERVATION OF FOODS, FOODSTUFFS OR NON-ALCOHOLIC BEVERAGES; CHEMICAL RIPENING OF FRUIT OR VEGETABLES
  • A23B2/00—Preservation of foods or foodstuffs, in general
  • A23B2/70—Preservation of foods or foodstuffs, in general by treatment with chemicals
  • A23B2/725—Preservation of foods or foodstuffs, in general by treatment with chemicals in the form of liquids or solids
  • A23B2/729—Organic compounds; Microorganisms; Enzymes
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K8/00—Cosmetics or similar toiletry preparations
  • A61K8/18—Cosmetics or similar toiletry preparations characterised by the composition
  • A61K8/30—Cosmetics or similar toiletry preparations characterised by the composition containing organic compounds
  • A61K8/67—Vitamins
  • A61K8/676—Ascorbic acid, i.e. vitamin C
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K15/00—Anti-oxidant compositions; Compositions inhibiting chemical change
  • C09K15/04—Anti-oxidant compositions; Compositions inhibiting chemical change containing organic compounds
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11B—PRODUCING, e.g. BY PRESSING RAW MATERIALS OR BY EXTRACTION FROM WASTE MATERIALS, REFINING OR PRESERVING FATS, FATTY SUBSTANCES, e.g. LANOLIN, FATTY OILS OR WAXES; ESSENTIAL OILS; PERFUMES
  • C11B5/00—Preserving by using additives, e.g. anti-oxidants
  • C11B5/0021—Preserving by using additives, e.g. anti-oxidants containing oxygen
  • C11B5/0028—Carboxylic acids; Their derivates
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11B—PRODUCING, e.g. BY PRESSING RAW MATERIALS OR BY EXTRACTION FROM WASTE MATERIALS, REFINING OR PRESERVING FATS, FATTY SUBSTANCES, e.g. LANOLIN, FATTY OILS OR WAXES; ESSENTIAL OILS; PERFUMES
  • C11B5/00—Preserving by using additives, e.g. anti-oxidants
  • C11B5/0042—Preserving by using additives, e.g. anti-oxidants containing nitrogen
  • C11B5/005—Amines or imines
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11B—PRODUCING, e.g. BY PRESSING RAW MATERIALS OR BY EXTRACTION FROM WASTE MATERIALS, REFINING OR PRESERVING FATS, FATTY SUBSTANCES, e.g. LANOLIN, FATTY OILS OR WAXES; ESSENTIAL OILS; PERFUMES
  • C11B5/00—Preserving by using additives, e.g. anti-oxidants
  • C11B5/0071—Preserving by using additives, e.g. anti-oxidants containing halogens, sulfur or phosphorus
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K2800/00—Properties of cosmetic compositions or active ingredients thereof or formulation aids used therein and process related aspects
  • A61K2800/40—Chemical, physico-chemical or functional or structural properties of particular ingredients
  • A61K2800/52—Stabilizers
  • A61K2800/522—Antioxidants; Radical scavengers

Definitions

• the present invention relates to compositions comprising an anti-oxidant solubilised in a hydrophobic solvent in which it would not normally be soluble.
• the present invention relates to compositions comprising ascorbic acid solubilised in a hydrophobic solvent in which it would not normally be soluble.
• anti-oxidants For many applications, e.g. in the pharmaceutical sciences, in food technology or the cosmetics industry, it is desired (and in certain cases essential) to employ anti-oxidants to limit oxidation of, for instance, an active ingredient or food ingredient.
• Anti-oxidants can be divided into two mam functional groups, the chelatmg agents which act by sequestering pro-oxidant ions, such as those of transition metals, while the second group are the free radical scavengers (cham-oreakers) , which have the effect of interrupting oxidative chain reactions.
• the latter may operate m a hy ⁇ ropnilic (normally aqueous) or a hydrophobic (e.g. lipid) environment, depending on their solubility characteristics.
• lipid-soluble, free-radical scavengers include natural anti-oxidants such as a- tocopnerol and 3-carotene, as well as synthetic ones, e.g. BHA and BHT.
• Ascorbic acid (Vitamin C) is a water- soluble free-radical scavenger (and thus will normally operate in this mode only in the aqueous phase) , but it also has an important role as a chelatmg anti-oxidant .
• very important anti-oxidant action of ascorbic acid is that t can interact synergistically with - ocopherol , thus resulting in a greatly increased component anti-oxidant activities.
• ⁇ -tocopnerol functions as the primary anti-oxidant which is able to repair a lipid free radical, thus interrupting the oxidation chain reaction while itself being converted to a free radical in the process.
• Ascorbic acid acts by regenerating the tocopheroxyl radical, thus restoring its anti-oxidant function. Synergistic relationships are also known to occur between other anti-oxidant species, but often different mechanisms apply.
• a requirement for ascorbic acid/ ⁇ -tocopherol synergistic action is that n order to interact, the two species must be able to come into close contact. This can be difficult in view of the fact that ascorbic acid is water soluble while ⁇ -tocopherol is lipid soluble. Such interactions may occur in a living cell since tocopherols are usually present in membranes which are in intimate contact with the aqueous cytoplasm c phase. It is therefore possible to duplicate this type of interaction in vitro using liposomes in place of biological membranes.
• a further available strategy is that of using a lipid-soluble derivative of ascorbic acid such as ascorbyl palm tate, which does interact synergistically with ⁇ -tocopnerol.
• ascorbyl palmitate is not very soluble and can require heat to dissolve, which paradoxically increases oxidative susceptibility of vulnerable compounds, for example polyunsaturates, and this therefore mitigates against its use in situations where these compounds are required to be protected, for example n the preparation of certain foodstuffs.
• UK patent application No. 9323588.5 discloses a process by which a hydrophilic species can be solubilised in a hydrophobic solvent in which it would not normally be soluble.
• the process relies on the surprising discovery that if a hydrophilic species is mixed with an amphiphile under certain conditions, the resultant composition will be readily soluble in lipophilic solvents such as oils.
• compositions comprising an anti-oxidant solubilised in a hydrophobic solvent in which it would not normally be soluble, are effective as anti-oxidant compositions.
• anti-oxidant species retain their anti-oxidant properties in such a non- aqueous environment.
• the present invention provides an anti-oxidant composition
• an anti-oxidant composition comprising at least one anti- oxidant species solubilised m a hydrophobic solvent m which t would not normally be soluble.
• compositions of the invention will be anhydrous.
• an anti-oxidant preparation is provided which does not contain water.
• the anti-oxidant species is selected from ascorbic acid, citric acid, phytic acid, pyrophospnate, EDTA, transferrm, ceruplasmm, metallothione , albumin, haptoglob , cyste e, glutathione, conjugated b le pigments (e.g. bilirubin and biliverd ) , uric acid, vanillic acid, vanillin, and Trolox.
• conjugated b le pigments e.g. bilirubin and biliverd
• the anti-oxidant is selected from ascorbic acid, cysteine, glutathione, conjugated bile pigments and uric acid.
• a particularly preferred anti-oxidant is ascorbic acid.
• solubilised refers to the anti-oxidant species being held m the hydrophobic solvent, the ansence of water, i.e. without the need for any water to be present.
• compositions of the present invention thus provide an anti-oxidant in a non-aqueous form to protect materials from oxidation, since it has been surprisingly found that such compositions are effective as a means of protecting against oxidation notwithstanding that the anti-oxidant is solubilised in a nydrophobic solvent
• compositions according to the invention are useful m that it is possible to provide lipid soluble anti-oxidants, e.g. vitamin E, in combination with one or more water soluble anti-oxidants, such as ascorbic acid, which act synergistically w th vitamin E, thus providing an enhanced anti-oxidant composition.
• lipid soluble anti-oxidants e.g. vitamin E
• water soluble anti-oxidants such as ascorbic acid
• the present invention provides an anti-oxidant composition
• an anti-oxidant composition comprising a lipid soluole anti-oxidant species, together with one or more anti- oxidants solubilised in a hydropnobic solvent in which the one or more other anti-oxidants would not normally be soluble .
• the lipid soluble anti-oxidant species can be selected from tocopherols (e.g. a- ocopherol) , 0-carotene, d ⁇ tocotrienol, quercetin, acacetin, BHA, BHT, TBHQ, propyl gallate and probucol .
• the lipid soluble anti-oxidant species is a tocopherol, particularly ⁇ - tocopherol, and the other anti-oxidant is one which can act synergistically with a -tocopherol, resulting in enhanced anti-oxidant activity, e.g. ascorbic acid, cyste e, glutathione, conjugated bile pigments or uric acid.
• compositions of the present invention can be prepared using the processes described in UK patent application No. 9323588.5.
• the present invention provides a process for the preparation of a single phase hydrophobic anti-oxidant preparation comprising at least one antioxidant species solubilised in a hydrophobic solvent in which it would not normally be soluble, the process comprising:
• the process can be halted at the end of stage (ii) and the resulting material can be stored under appropriate conditions until it is needed to generate the single-phase preparation by providing a hydrophobic solven .
• the term "chemical interaction” relates to an interaction such as a covalent or ionic bond or a hydrogen bond. It is not intended to include van der Waals forces or other interactions of that order of magnitude.
• This process can also be used to produce a composition comprising vitamin E together with one or more other anti-oxidants which act synergistically with vitamin E, and which are not normally soluble in a hydrophobic solvent, to enhance anti-oxidant activity.
• vitamin E can be added at either or both of stages (i) and (iii) described above.
• amphiphiles which may be used to prepare the compositions of the present invention and zwitterionic amphiphiles such as phospholipids are among those which have been found to be especially suitable.
• Phospholipids having a phosphatidyl choline head group have been used with particular success and examples of such phospholipids include phosphatidyl choline (PC) itself, lyso-phosphatidyl choline (lyso-PC) , sphmgomyel , derivatives of any of these, for example hexadecylphospnochol e or amphiphilic polymers containing phosphoryl choline and halogenated amphiphiles, e.g.
• phosphatidyl choline PC
• lecithin Suitable natural lecithins may be derived from any convenient source, for example egg and, in particular, soya. In most cases, it is preferable to select an amphiphile which is chemically similar to the chosen hydrophobic solvent and this is discussed in greater detail below.
• the hydropnobic solvent of choice will depend on the purpose for which the composition is intended, on the anti-oxidant species to be solubilised and on the amphiphile.
• Suitable solvents include non-polar oils such as mineral oils, squalane and squalene, long chain fatty acids with unsaturated fatty acids such as oieic and linoleic acids being preferred, alconols, particularly medium chain alcohols such as octanol and branched long chain alcohols sucn as pnytol , isoprenoids, e.g.
• nerol and geraniol other alcohols such as t- butanol, terpineoi, monoglycendes such as glycerol monooleate ( G M O ) , othei esters, e.g. ethyl acetate, amyl acetate and bornyl acetate, digiycerides and triglycerides, particularly medium chain triglycerides and mixtures thereof, Halogenated analogues of any of the above including halogenated oils, e.g. long chain fluorocarbons, and iodinated triglycerides, e.g. lipidiol. In particular, polyunsaturated oils or satura t ed oils are preferred.
• the preparations cf t he invention are optically clear and this can be moni t ored b y measuring turbidity at visual wave lengths and , in some cases, by checking for sedimentation over a period of time.
• orien t a t ion of amphiphile molecules into an array with their hydrophilic head groups facing the moieties of an an t i-oxidan t species can be achieved in several ways and examples of particularly suitable methods are discussed more detail below.
• an anti-oxidant species is mixed with a dispersion of an amphiphile in a hydrophilic solvent, such that the amphiphile molecules form an assembly in which the hydrophilic head groups face outwards towards the hydrophilic phase which contains the anti-oxidant species.
• the hydrophilic solvent is then removed to leave a dry composition which the hydrophilic head groups of the amphiphile molecules are orientated towards the anti-oxidant species.
• the hydrophilic solvent is water although other polar solvents may be used.
• the form taken by the amphiphile assembly may be micelles, unilamellar vesicles, preferably small unilamellar vesicles which are generally understood to have a diameter of about 25 nm, multilamellar vesicles or tubular structures, for example cochleate cylinders, hexagonal pnase, cubic phase or myel type structures.
• the form adopted will depend upon the amphiphile which is used and, for example, amphiphiles such as phosphatidyl choline (PC) tend to form small unilamellar vesicles wnereas lyso-phosphatidyl choline forms micelles.
• PC phosphatidyl choline
• the hydrophobic tails of the amphiphile molecules face inwards towards the centre of the structure while the hydrophilic head groups face outwards towards the solvent in whicn the anti-oxidant species is dispersed.
• the weight ratio of amphiphile:anti-oxidant species will generally be in the region of from 1:1 to 100:1, preferably from 2:1 to 20:1 and most preferably about 8:1 for PC and 4:1 for lyso-PC.
• ratios are preferred ratios only and, in particular, it should be pointed out that the upper limit is set by economic considerations which mean that it is preferable to use the minimum possible amount of amphiphile.
• the lower limit is somewhat more critical and it is likely that ratios of 2:1 or below would only be used cases where the anti-oxidant species has a significant hydrophobic portion or is exceptionally large.
• a second method for the preparation of a composition containing an array of amphiphiles with their nead groups pointing towards the ant -oxidant species is to co- soiubiiise the anti-oxidant species and the amphiphile in a common solvent followed by removal of the solvent.
• solutions of the present invention may either be used alone or they may be combined with an aqueous phase to form an emulsion or similar two pnase composition wnich forms yet a further aspect of the invention.
• a two phase composition comprising a hydrophilic phase and a hydropnobic phase, the hydrophobic phase comprising a preparation of an anti-oxidant species as described herein .
• the hydropnobic phase will be dispersed in the hydrophilic phase.
• the two phase compositions may be emulsions which may either be transient or stable, depending on the purpose for which they are required.
• the average size of the emulsion particles will depend on the exact nature of both the hydrophobic and the aqueous phases. However, t may be in the region of 2 ⁇ m
• Dispersion of the hydrophobic preparation the aqueous phase can be achieved by mixing, for example either by vigourous vortex g for a short time for example about 10 to 60 seconds, usually about 15 seconds, or by gentle mixing for several hours, for example using an orbital shaker.
• Emulsions containing the hydrophobic preparations cf the invention can also be used in the preparation of microcapsules. If the emulsion is formed from a gelatm- contai mg aqueous phase, the gelatin can be precipitated from the solution by coacervation o ⁇ known metho ⁇ s and will form a film around the ⁇ roplets of the anti-oxidant- containing hydrophobic phase. On removal of the hydrophilic phase, microcapsules will remain. This technology is known in the ar , but has proved particularly useful in combination with the preparations of the present invention.
• the invention provides. (i) the use of an anti-oxidant composition of the invention in the preparation of a pharmaceutical or cosmetic formulation or a foodstuff;
• composition comprising at least one anti-oxidant species solubilised in a hydrophobic solvent in which it would not normally be soluble, for use as an anti- oxidation agent;
• Example 3 refers to the figures in which:
• FIGURE 1 shows a comparison of oxidation index
• ratio of non-saturated fatty acid remaining m oil compared to amount of non-oxidisable interval standard for preparations with and without ascorbic acid alone or in combination with -tocopherol.
• FIGURE 2 shows a comparison of oxidation index for preparations with and without ascorbic acid in the presence of linoleic acid and linoleic acid and Soy
• FIGURE 3 shows a comparison of oxidation index or preparations with and without ascorbic acid alone and with linoleic acid.
• aqueous dispersion of soy phosphatidyl choline was prepared, containing 50mg/g of suspension, flushed thoroughly with nitrogen, and sonicated in 3ml aliquots at an amplitude of 8 microns peak to peak. Each aliquot was subjected to a total sonication time of 4 minutes, in pulses of 30 seconds interspersed by cooling for 30 seconds in an ice slurry bath.
• the resulting opalescent dispersions of small unilamellar vesicles (SUV) were pooled and then centrifuged for 15 minutes to remove particles of titanium.
• a trilinole /linoleic acid/PC oil phase of similar composition but lacking ascorbic acid was prepared by freeze-drying 0.7g of SUV and then dissolving the lyophilate m 1.75g of the same trilinolein/linole c acid solution.
• a low ascorbate dispersion was prepared by diluting 0.25g of the high ascorbate one with 750mg of the above oil phase.
• Into 3 small glass vials were added aliquots of 0.6, 0.6 and 0.5mg respectively of a- tocopherol . For reasons of accuracy, this was added as a 0.6% ethanolic solution, the ethanol being subsequently removed under a stream of nitrogen.
• fatty acid components in each vial were then converted to methyl ester derivatives by standard procedures and measured by GC. Results were expressed in terms of an Oxidation Index, which is defined here as the percentage of remaining 18 : 2 fatty acids (derived from trilinolein and linoleic acid) relative to 17 : 0 fatty acids (heptadecanoic acid) .
• aqueous phospnolipid dispersion was prepared containing lOO g soy PC/g and converted to SUV as described in Example 3.
• Appropriate amounts of SUV were mixed with aqueous 1% ascorbic acid solutions to provide mixtures having PC .- ascorbic acid ratios of 13.33 : 1, and tne mixtures were shell-frozen and freeze-dried.
• the resulting lyophilates were mixed with refined fish oil containing 2% w/w of linoleic acid (as a solubilisation enhancer) to give clear dispersions containing 1.5 or 3.0 mg ascorbic acid/g of oil phase.
• Control oil phases were also prepared comprising pure fish oil, and also fish oil containing 2% linoleic acid both the absence and presence of 2% w/w of dissolved soy PC de the same concentration as in the dispersion containing 1.5mg ascorbic acid/g) .
• the two ascorbic acid-conta mg dispersions, and the three oil phase controls, were each distributed as 50mg aliquots into c ⁇ mpable glass chromatography vials as in Example 3, and again stored uncapped in a 37 C incubator, le under conditions for accelerated oxidation of lipids.
• a lyophilate of soy PC and ascorbic acid was prepared as described in Example 4 and then mixed with sunflower oil containing 2% w/w of added linoleic acid to form a clear dispersion containing 1.5mg ascorbic acid/g of oil phase.
• Oil phase controls were prepared comprising pure sunflower oil and also sunflower oil containing 2% linoleic acid, in the absence and presence of 2% w/w of soy PC. 50mg aliquots of the ascorbic acid dispersion and of the 3 oil phase controls, were incubated under conditions for accelerated lipid oxidation as described in Example 4, and were sampled periodically and analysed in the same way.

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• 1994
  • 1994-12-09 GB GBGB9424908.3A patent/GB9424908D0/en active Pending
• 1995
  • 1995-12-08 WO PCT/GB1995/002888 patent/WO1996017899A1/en not_active Ceased
  • 1995-12-08 CN CN95196630.8A patent/CN1168687A/zh active Pending
  • 1995-12-08 EP EP95940348A patent/EP0796302A1/de not_active Ceased
  • 1995-12-08 FI FI972421A patent/FI972421A7/fi unknown
  • 1995-12-08 AU AU41826/96A patent/AU700084B2/en not_active Ceased
  • 1995-12-08 NZ NZ297052A patent/NZ297052A/xx unknown
  • 1995-12-08 CA CA002207325A patent/CA2207325A1/en not_active Abandoned
  • 1995-12-08 JP JP8517434A patent/JPH10510563A/ja active Pending
  • 1995-12-10 IL IL11631295A patent/IL116312A0/xx unknown
  • 1995-12-11 ZA ZA9510506A patent/ZA9510506B/xx unknown
• 1997
  • 1997-06-06 NO NO972609A patent/NO972609L/no unknown

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