Method of forming a liposome comprising a derivative of curcumin

Abstract

A method of forming a liposome comprising a derivative of curcumin, comprising: a first step, in which curcumin is reacted with a fatty acid ester to form a derivative of curcumin, wherein the reactio

Description

FIELD This invention relates to a method of forming a liposome comprising a derivative of curcumin and an encapsulated liposome comprising a derivative of curcumin, and the use of the encapsulated liposome as a medicament or supplement BACKGROUND Curcumin is a bright yellow chemical produced by plants of the Curcuma longa species, and is the principal curcuminoid of turmeric (Curcuma longa). Curcumin, (1 E,6E)-1,7-bis(4-hydroxy-3-methoxyphenyl)hepta-1,6-diene-3,5-dione), comprises two methoxy substituted phenol rings linked by an a,p-unsaturated p-diketone moiety. Curcumin is poorly soluble in water due to its hydrophobic nature, but it is easily soluble in organic solvents. It is a diketone tautomer, existing in the enol form in organic solvents and in the keto form in water: IT curcumin Curcumin is an active substance and believed to provide anti-inflammatory, antioxidant, antiproliferative and antiangiogenic effects in humans. Phase I clinical trials have shown that curcumin is safe even at high doses (12 g / day) in humans, but exhibits poor bioavailability. The low detected level of curcumin in plasma and tissues appears to be due to its poor solubility in water, low absorption rate, rapid biotransformation to metabolites and rapid systemic elimination. Without wishing to be bound by theory, it is believed curcumin's oral bioavailability is often limited due to low absorption by the small intestine, significant reductive and conjugative metabolism in the liver, and excretion via the gall bladder. It is believed that metabolism of curcumin occurs due to phase-l and phase-ll biotransformation. In phase-l metabolism, the double bonds of curcumin are reduced by the action of reductase to form di, tetra, hexa, and octa hydro curcumin. In phase-ll metabolism, curcumin and its hydrogenated metabolites are conjugated with glucuronide or sulphate by the action of glucuronidases or sulfotransferases at the phenolic site of curcumin. Curcumin is not very chemically stable and, for example, phenol groups on curcumin can be used to conjugate the substance with its reduced metabolites. It is believed that the enhancement of the solubility and / or bioavailability of curcumin is important for potential clinical application. As such, there is a need for improved curcumin formulations, and in particular those having improved bioavailability. SUMMARY Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. The detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended to be given by way of example only. In a first aspect of the invention, there is provided a method of forming a liposome comprising a derivative of curcumin, comprising: a first step, in which curcumin is reacted with a fatty acid ester to form a derivative of curcumin, wherein the reaction is carried out in a reaction medium; and a second step, in which the derivative of curcumin is combined with a liposome forming compound to form a liposome comprising the derivative of curcumin, and wherein the derivative of curcumin is not isolated from the reaction medium following the first step. As shown herein, curcumin may be reacted with a fatty acid ester to form a derivative of curcumin. Fatty acid esters are a type of ester that result from the condensation reaction of a fatty acid with an alcohol. A fatty acid is a carboxylic acid with an aliphatic chain. The aliphatic chain may comprise saturated or unsaturated carbon chains, and optionally comprises fully saturated carbon chains. The aliphatic chain may comprise a branched or unbranched chain, and optionally comprises an unbranched chain. The aliphatic chains may be optionally substituted. The aliphatic chain may comprise an even or odd number of carbon atoms, and optionally there is an even number of carbon atoms. The fatty acid may comprise medium-chain fatty acids with an aliphatic chain of from 6 to 12 carbon atoms. For example, the fatty acid may comprise one or more of propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid (shown below), pelargonic acid, capric acid, undecylic acid and lauric acid. O caprylic acid The alcohol component of the fatty acid ester may comprise one hydroxyl group, or two or more hydroxyl groups (a polyol). The polyol may comprise two, three or four hydroxyl groups (diols, triols, and tetrols, respectively). The alcohol component may comprise glycerol, which is a triol and so comprises three hydroxyl groups. Fatty acid esters result from the condensation reaction of a fatty acid with an alcohol. When the alcohol component is glycerol, the fatty acid esters produced may be monoglycerides (derived from glycerol and one fatty acid), diglycerides (derived from glycerol and two fatty acids), or triglycerides (derived from glycerol and three fatty acids). The fatty acid ester may comprise a monoglyceride, diglyceride, and / or triglyceride. The fatty acid ester may comprise a triglyceride, and optionally a medium chain triglyceride (MCT). MCTs are triglycerides with two or three of the fatty acids having an aliphatic chain of between 6 and 12 carbon atoms. Each aliphatic chain may independently comprise any number of carbon atoms from 6 to 12 carbon atoms. Optionally, each aliphatic chain may independently comprise 8 or 10 carbon atoms. Each aliphatic chain may be different, and may be optionally substituted. Compound I below is a typical example of a MCT, comprising the glycerol derived backbone, and three aliphatic chains derived from medium chain fatty acids (caprylic acid, comprising an aliphatic chain of 8 carbon atoms (C8:0), and capric acid, comprising an aliphatic chain of 10 carbon atoms (C10:0)). compound I MCTs are naturally present in many foods. For example, one of the most abundant sources of MCTs is coconut oil, which comprises more than 60% by mass MCTs. Generally, MCTs may be derived from the fatty acids caproic acid (comprising an aliphatic chain of 6 carbon atoms, C6:0), caprylic acid (comprising an aliphatic chain of 8 carbon atoms, C8:0), capric acid (comprising an aliphatic chain of 10 carbon atoms, C10:0), and / or lauric acid (comprising an aliphatic chain of 12 carbon atoms, C12:0). Without wishing to be bound by theory, it is believed that MCTs are quickly absorbed and metabolized by the liver and utilized by the body. MCTs promote the production of ketones, providing a source of energy for brain and muscle tissue. Calories from MCTs are normally used more efficiently for energy production than calories from glucose and are therefore less likely to turn into adipose tissue (body fat). Further, it is believed that MCTs boost the absorption (bioavailability) of certain compounds, can support and improve cognitive functions, support atherosclerosis prevention, a healthy lipid metabolism and the immune system, and can increase energy levels and physical endurance. The MCT may be of food grade. The MCT may be derived from natural sources such as coconut oil, milk fat and / or palm kernel oil. Optionally, the MCT may be derived from coconut oil. Caprylic acid is one of the three primary fatty acids found in coconut oil. The MCT used in the method of the present invention may comprise a mixture of different MCTs. Optionally, the MCT may comprise a mixture of different MCTs derived from the fatty acids caprylic acid (C8:0) and capric acid (C10:0). Optionally, the MCT may comprise an MCT derived from the fatty acids caprylic acid (C8:0) and capric acid (C10:0). Without wishing to be bound by theory, it is believed that MCTs derived from the fatty acids caprylic acid and capric acid provide enhanced intestinal absorbtion, advantageously react quickly in the body to produce ketones, and so may be used by mitochondria as an efficient energy source. The use of caprylic acid may provide rapid absorption and quick conversion into ketones, which can provide a readily available energy source for the body. Capric acid may also be efficiently converted into ketones. Both caprylic acid and capric acid may be easily digested and can provide potential benefits in weight management, cognitive function, and increased energy expenditure. In the method of the present invention, curcumin reacts with a fatty acid ester to form a derivative of curcumin. The fatty acid ester may react at an oxygen atom of curcumin, and optionally fatty acid ester may react at an aromatic oxygen atom of curcumin. The fatty acid ester may react at the phenolic group of curcumin. In particular, curcumin may react with a MCT to form the derivative of curcumin, and the newly formed bond between curcumin and the MCT is an ester. The MCT may react at one or both of the phenolic sites of curcumin, and optionally at both phenolic sites of curcumin. Without wishing to be bound by theory, it is believed that the derivative of curcumin, and in particular the derivative of curcumin derived from reaction with a MCT, may protect the curcumin moiety against metabolic processes and provide stability and greater activity, compared to curcumin. Without wishing to be bound by theory, it is believed that caprylic acid, in addition to increasing absorption due to the carboxylic acid groups, may react with the phenolic groups of curcumin and prevents methylation. The w / w ratio of curcumin to fatty acid ester in the first step of the method may be in range 0.4-2.0:1, 0.5-1.9:1, 0.6-1.8:1, 0.7-1.7:1, 0.8-1.6:1, 0.9-1.5:1, 1.0-1.4:1, 1.1-1.3:1, 1.15-1.25:1, or 1.2:1. Optionally, the w / w ratio of curcumin to fatty acid ester in the first step of the method is about 1.2 to 1 (12% to 10%). In the second step of the method of the invention, the derivative of curcumin is combined with a liposome forming compound to form a liposome comprising the derivative of curcumin. A liposome is a small artificial vesicle, generally spherical in shape, having at least one lipid bilayer. Due to their hydrophobicity and / or hydrophilicity, biocompatibility and particle size liposomes can be used as drug delivery vehicles for administration of pharmaceutical drugs and nutrients. The liposomes may be a multilamellar vesicle (MLV) with several lamellar phase lipid bilayers. The liposome forming compound may comprise a phospholipid. Phospholipids are a class of lipids whose molecule has a hydrophilic "head" containing a phosphate group and two hydrophobic "tails" derived from fatty acids, joined by an alcohol residue (usually a glycerol molecule). A suitable phospholipid capable of forming a liposome with the derivative of curcumin may be used. For example, dietary phospholipids derived from soybeans, egg yolk, milk, or marine organisms (fish, roe or krill) may be used. The phospholipid may comprise phospholipon® 80H, (which comprises phospholipids, hydrogenated, with 70% phosphatidylcholine; CAS-No. 92128-87-5). Phospholipon® 80H is a natural emulsifier derived from soya oil. The w / w ratio of the derivative of curcumin to the liposome forming compound in the second step of the method is in the range 1-15:1, 2-14:1, 3-13:1,4-12:1, 5-11:1, 6-10:1, 7-9:1, 7.5-8.5:1, or about 8:1. Optionally, w / w ratio of the derivative of curcumin to the liposome forming compound in the second step of the method is about 8:1 (12% to 1.5%). Advantageously, the derivative of curcumin may not be isolated from the reaction medium following the first step. In other words, the reaction may be carried out in one pot, and there is no need to isolate the derivative of curcumin from the reaction medium before carrying out the second step of the method. This is advantageous as the method of the invention may be more efficient and save on costs. It may also allow for the protection of the curcumin derivative in the liposome. Without wishing to be bound by theory, it is believed that the use of the derivative of curcumin, rather than curcumin, in forming the liposome in the second step allows for a more stable liposome. This is due to the presence of aliphatic chains of the fatty acid residues of the derivative of curcumin combining with the fatty acid tails of the phospholipid. There is no need for the use of organic solvents in the second step of the method of the invention. In other words, the second step of the method may be carried out in the absence of organic solvents. This is advantageous as organic solvents are generally environmentally unfriendly and may not be present in food grade substances. Any organic solvents which may be used in the first step of the method may be removed prior to the second step. If any organic solvents are used in the first step, these organic solvents may be removed prior to the second step. Advantageously, this may also remove water, helping driving the reaction to completion. Optionally, a surfactant may be used in the second step of the method of the invention. For example, a suitable surfact may be sorbitan monostearate (Span 60®). The surfactant may facilitate the combining of the derivative of curcumin and the liposome forming compound, and increase the stability of the liposome. The method of the first aspect of the invention may comprise the following further step: a third step, in which the liposome comprising the derivative of curcumin is combined with a polymer to form an encapsulated liposome comprising the derivative of curcumin. The polymer coats and provides a protective layer around each liposome comprising a derivative of curcumin, which helps to enhance the stability and performance of the liposomes in different environments, such as in aqueous solutions. In particular, the encapsulation of the liposome may prevent the release of the derivative of curcumin in the acidic stomach environment therefore allowing the derivative of curcumin to enter the lower digestive tract and to reach the blood plasma. The polymer may comprise an oligosaccharide, which is a saccharide polymer containing typically three to ten of monosaccharides. The oligosaccharide may comprise cyclic oligosaccharides (cyclodextrins), which are composed of D-glucose units connected via alpha(1,4) glycosidic bonds. For example, cyclodextrins may comprise contain six D-glucose units (alpha-cyclodextrin); seven D-glucose units (beta-cyclodextrin) or eight D-glucose units (gamma-cyclodextrin). The cyclodextrins may be derivatized through esterification at positions two, three and / or six. The polymer may comprise a beta-cyclodextrin polymer. Beta-cyclodextrin (see compound II) is a cyclic oligosaccharide of glucopyranose, containing a hydrophobic central cavity and hydrophilic outer surface. compound II The liposome comprising the derivative of curcumin may be encapsulated in the hydrophobic central cavity. The use of beta-cyclodextrin polymer is advantageous due to its high encapsulation efficiency and stabilization properties with the derivative of curcumin, and due to improving compound solubility in aqueous environments. Beta-cyclodextrin has low aqueous solubility. The solubility of beta-cyclodextrin was investigated at different pH levels, and found to be most soluble with 2.75 grams per 100 mL of acidic environment with a pH of 3.5 at 35°C. Accordingly, the third step of the method of the present invention may advantageously be carried out in acidic solution, and optionally at a pH of between 3 and 4, and optionally at a pH of about 3.5. Following the acidification of the beta-cyclodextrin, the temperature may be lowered to about 10°C to aid the encapsulation of the liposome comprising the derivative of curcumin within the beta-cyclodextrin hydrophobic central cavity. At this stage, when the liposomes are formed, they may be coated with cyclodextrin polymer. Cyclodextrins are nanocapsules formed from glucose and have glycosidic linkages of the -1,4a type. Guest-host interactions in cyclodextrins are based on physical forces rather than chemical bonding. Additionally, the type of guest molecule is highly dependent on the size of the cyclodextrin cavity used. The most stable complexes are formed with guest molecules that are perfectly sized (neither too small nor too large) to fit within the cyclodextrin cavity and, figuratively speaking, adhere to the molecular rule within the cavity. The first, second and / or third steps of the method of the invention may be carried out in an inert atmosphere, and optionally in an argon atmosphere. Curcumin can be chemically unstable and can be sensitive to oxygen, temperature, acid and alkali. In a second aspect of the invention, there is provided a liposome comprising the derivative of curcumin prepared by the method of the invention. In a third aspect of the invention, there is provided an encapsulated liposome comprising the derivative of curcumin. The encapsulated liposome may be in the form of a powder. Following the third step of the method, the reaction mixture comprising the encapsulated liposome comprising the derivative of curcumin is homogenized, then dispersed and dried using a spray drier to prevent aggregation. The powder may be dried with spray dryer at temperature of about 175°C, and the output temperature is about 90°C. The coating of beta-cyclodextrin advantageously provides protection of the liposome during the spray drying process. The powder form enables convenient storage and administering of the encapsulated liposomes. For example, the powder may be administered orally, and formed into granules, tablets or capsules, or added to foods. The mean diameter of the encapsulated liposomes may be from 0.5 to 2.2 pm, 0.6 to 2.1 pm, 0.7 to 2.0 pm, 0.8 to 1.9 pm, 0.9 to 1.8 pm, 1.0 to 1.7 pm, 1.1 to 1.6 pm, 1.2 to 1.5 pm, or 1.3 to 1.4 pm. The average diameter of the encapsulated liposomes may be between 1 and 2 pm, and optionally about 1.4 pm. The liposome comprising the derivative of curcumin, and / or the encapsulated liposome, may be used as a medicament for the treatment of various conditions. For example, an effective therapeutic amount and / or a therapeutic dose of the encapsulated liposome comprising the derivative of curcumin, and / or the liposome comprising the derivative of curcumin, may be used to provide anti-inflammatory, antioxidant, antiproliferative and antiangiogenic effects in humans. The liposome comprising the derivative of curcumin, and / or the encapsulated liposome comprising the derivative of curcumin, may be used as a food or supplement. The liposome comprising a derivative of curcumin may act as a pro-drug. The supplement may be a medicinal supplement. In a fourth aspect of the invention, there is provided a pharmaceutically acceptable composition, or pharmaceutical composition, comprising the liposome comprising the derivative of curcumin, or the encapsulated liposome comprising the derivative of curcumin. The pharmaceutically acceptable composition, or pharmaceutical composition, may be used as a medicament. 14 01 25 In a fifth aspect of the invention, there is provided a food or supplement comprising the liposome comprising the derivative of curcumin, or the encapsulated liposome comprising the derivative of curcumin. 5 Without wishing to be bound by theory, it is believed that the encapsulated liposome advantageously increases the bioavailability of curcumin by resistance to metabolic processes, increased absorption into the small intestine, and prolonging the half-life in plasma. 10 FIGURES Embodiments in accordance with the invention will now be described with reference to the accompanying drawings, in which: Figure 1 shows scanning electron microscope images of the encapsulated liposomes. 15 Figure 2 shows scanning electron microscope images of the encapsulated liposomes. Figure 3 shows the mean diameter of the encapsulated liposomes. Figure 4 shows a transmission electron microscope image of the encapsulated liposome. Figure 5 shows a Fourier-transform infrared spectroscopy (FTIR) spectrum including curcumin and the encapsulated liposome comprising a derivative of curcumin. 20 Figure 6 shows the intensity of microencapsulation liposome-curcumin, where the diameters of nanoparticles are about 1000nm (Eff. Diam. (nm) = 1039.83). Figure 7 shows that the phenolic group of curcumin in range 9pmm has been converted to ester groups. 25 Figure 8 shows the measurement of encapsulation efficiency (EE%) by UV absorption. DESCRIPTION The description of illustrative embodiments according to principles of the present invention is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description. The term “prodrug” as used herein refers to a compound which is metabolically or chemically activated in vivo to afford an active parent drug molecule which itself affords the therapeutic pharmacological effect. The use prodrugs is well precedented, and indeed many marketed drugs are prodrugs (Rautio, J. et al. Nat. Rev. Drug Discov. 17, 559-587 (2018)). The term “treatment”, in relation to the uses of any of the compounds described herein, is used to describe any form of intervention where a compound is administered to a subject suffering from, or at risk of suffering from, or potentially at risk of suffering from the disease or disorder in question. Thus, the term “treatment” covers both preventative (prophylactic) treatment and treatment where measurable or detectable symptoms of the disease or disorder are being displayed. The term “effective therapeutic amount” (for example in relation to methods of treatment of a disease or condition) refers to an amount of the compound which is effective to produce a desired therapeutic effect. For example, if the condition is pain, then the effective therapeutic amount is an amount sufficient to provide a desired level of pain relief. The desired level of pain relief may be, for example, complete removal of the pain or a reduction in the severity of the pain. Terms such as “alkyl” are used in their conventional sense (e.g. as defined in the IUPAC Gold Book), unless indicated otherwise, “optionally substituted” as applied to any group means that the said group may if desired be substituted with one or more substituents, which may be the same or different. To the extent that any of the compounds described have chiral centres, the present invention extends to all optical isomers of such compounds, whether in the form of racemates or resolved enantiomers. Also encompassed are any solvates of the compounds and their salts. Preferred solvates are solvates formed by the incorporation into the solid state structure (e.g. crystal structure) of the compounds of the invention of molecules of a non-toxic pharmaceutically acceptable solvent (referred to below as the solvating solvent). Examples of such solvents include water, alcohols (such as ethanol, isopropanol and butanol) and dimethylsulfoxide. Solvates can be prepared by recrystallising the compounds of the invention with a solvent or mixture of solvents containing the solvating solvent. Whether or not a solvate has been formed in any given instance can be determined by subjecting crystals of the compound to analysis using well known and standard techniques such as thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray crystallography. The solvates can be stoichiometric or non-stoichiometric solvates. Particular solvates may be hydrates, and examples of hydrates include hemihydrates, monohydrates and dihydrates. For a more detailed discussion of solvates and the methods used to make and characterise them, see Bryn et al, Solid-State Chemistry of Drugs, Second Edition, published by SSCI, Inc of West Lafayette, IN, USA, 1999, ISBN 0-967-06710-3. The term “pharmaceutical composition” in the context of this invention means a composition comprising an active agent and comprising additionally one or more pharmaceutically acceptable additives. The composition may further contain ingredients selected from, for example, diluents, adjuvants, excipients, vehicles, preserving agents, fillers, disintegrating agents, wetting agents, emulsifying agents, suspending agents, sweetening agents, flavouring agents, perfuming agents, antibacterial agents, antifungal agents, lubricating agents and dispersing agents, depending on the nature of the mode of administration and dosage forms. The compositions may take the form, for example, of tablets, dragees, powders, elixirs, syrups, liquid preparations including suspensions, sprays, inhalants, tablets, lozenges, emulsions, solutions, cachets, granules, capsules and suppositories, as well as liquid preparations for injections, including liposome preparations. Therapeutic dosages may be varied depending upon the requirements of the patient, the severity of the condition being treated, and the compound being employed. Determination of the proper dosage for a particular situation is within the skill of the art. Generally, treatment is initiated with the smaller dosages which are less than the optimum dose of the compound. Thereafter the dosage is increased by small increments until the optimum effect under the circumstances is reached. For convenience, the total daily dosage may be divided and administered in portions during the day if desired. The magnitude of an effective dose of a compound will, of course, vary with the nature of the severity of the condition to be treated and with the particular compound and its route of administration. The selection of appropriate dosages is within the ability of one of ordinary skill in this art, without undue burden. While it is possible for the active compound to be administered alone, it is preferable to present it as a pharmaceutical composition (e.g. formulation). Accordingly, in some embodiments of the invention, there is provided a pharmaceutical composition comprising a liposome comprising a derivative of curcumin, or an encapsulated liposome comprising a derivative of curcumin, as defined above together with at least one pharmaceutically acceptable excipient. The composition may be a tablet composition. The composition may be a capsule composition. The pharmaceutically acceptable excipient(s) can be selected from, for example, carriers (e.g. a solid, liquid or semi-solid carrier), adjuvants, diluents (e.g. solid diluents such as fillers or bulking agents; and liquid diluents such as solvents and co-solvents), granulating agents, binders, flow aids, coating agents, release-controlling agents (e.g. release retarding or delaying polymers or waxes), binding agents, disintegrants, buffering agents, lubricants, preservatives, anti-fungal and antibacterial agents, antioxidants, buffering agents, tonicityadjusting agents, thickening agents, flavouring agents, sweeteners, pigments, plasticizers, taste masking agents, stabilisers or any other excipients conventionally used in pharmaceutical compositions. The term “pharmaceutically acceptable” as used herein means compounds, materials, compositions, and / or dosage forms which are, within the scope of sound medical judgment, suitable for use in contact with the tissues of a subject (e.g. a human subject) without excessive toxicity, irritation, allergic response, or other problem or complication, commensurate with a reasonable benefit / risk ratio. Each excipient must also be “acceptable” in the sense of being compatible with the other ingredients of the formulation. Pharmaceutical compositions containing liposomes comprising a derivative of curcumin, and / or encapsulted liposomes comprising a derivative of curcumin, can be formulated in accordance with known techniques, see for example, Remington’s Pharmaceutical Sciences, Mack Publishing Company, Easton, PA, USA. The pharmaceutical compositions can be in any form suitable for oral, parenteral, topical, intranasal, intrabronchial, sublingual, ophthalmic, otic, rectal, intra-vaginal, or transdermal administration. Pharmaceutical dosage forms suitable for oral administration include tablets (coated or uncoated), capsules (hard or soft shell), caplets, pills, lozenges, syrups, solutions, powders, granules, elixirs and suspensions, sublingual tablets, wafers or patches such as buccal patches. Tablet compositions can contain a unit dosage of active compound together with an inert diluent or carrier such as a sugar or sugar alcohol, eg; lactose, sucrose, sorbitol or mannitol; and / or a non-sugar derived diluent such as sodium carbonate, calcium phosphate, calcium carbonate, or a cellulose or derivative thereof such as microcrystalline cellulose (MCC), methyl cellulose, ethyl cellulose, hydroxypropyl methyl cellulose, and starches such as corn starch. Tablets may also contain such standard ingredients as binding and granulating agents such as polyvinylpyrrolidone, disintegrants (e.g. swellable crosslinked polymers such as crosslinked carboxymethylcellulose), lubricating agents (e.g. stearates), preservatives (e.g. parabens), antioxidants (e.g. BHT), buffering agents (for example phosphate or citrate buffers), and effervescent agents such as citrate / bicarbonate mixtures. Such excipients are well known and do not need to be discussed in detail here. Tablets may be designed to release the drug either upon contact with stomach fluids (immediate release tablets) or to release in a controlled manner (controlled release tablets) over a prolonged period of time or with a specific region of the Gl tract. The pharmaceutical compositions typically comprise from approximately 1% (w / w) to approximately 95%, preferably% (w / w) active ingredient and from 99% (w / w) to 5% (w / w) of a pharmaceutically acceptable excipient (for example as defined above) or combination of such excipients. Preferably, the compositions comprise from approximately 20% (w / w) to approximately 90% (w / w) active ingredient and from 80% (w / w) to 10% of a pharmaceutically excipient or combination of excipients. The pharmaceutical compositions comprise from approximately 1% to approximately 95%, preferably from approximately 20% to approximately 90%, active ingredient. Pharmaceutical compositions according to the invention may be, for example, in unit dose form, such as in the form of ampoules, vials, suppositories, pre-filled syringes, dragees, powders, tablets or capsules. Tablets and capsules may contain, for example, 0-20% disintegrants, 0-5% lubricants, 0-5% flow aids and / or 0-99% (w / w) fillers / or bulking agents (depending on drug dose). They may also contain 0-10% (w / w) polymer binders, 0-5% (w / w) antioxidants, 0-5% (w / w) pigments. Slow release tablets would in addition typically contain 0-99% (w / w) releasecontrolling (e.g. delaying) polymers (depending on dose). The film coats of the tablet or capsule typically contain 0-10% (w / w) polymers, 0-3% (w / w) pigments, and / or 0-2% (w / w) plasticizers. Parenteral formulations typically contain 0-20% (w / w) buffers, 0-50% (w / w) cosolvents, and / or 0-99% (w / w) Water for Injection (WFI) (depending on dose and if freeze dried). Formulations for intramuscular depots may also contain 0-99% (w / w) oils. The pharmaceutical formulations may be presented to a patient in “patient packs” containing an entire course of treatment in a single package, usually a blister pack. The liposome comprising the derivative of curcumin, or encapsulated liposome comprising the derivative of curcumin, will generally be presented in unit dosage form and, as such, will typically contain sufficient compound to provide a desired level of biological activity. The active compound will be administered to a patient in need thereof (for example a human or animal patient) in an amount sufficient to achieve the desired therapeutic effect (effective amount). The precise amounts of compound administered may be determined by a supervising physician in accordance with standard procedures. Moreover, the features and benefits of the invention are illustrated by reference to the exemplified embodiments. Accordingly, the invention expressly should not be limited to such exemplary embodiments illustrating some possible non-limiting combination of features that may exist alone or in other combinations of features; the scope of the invention being defined by the claims appended hereto. Figures 1 and 2 show scanning electron microscope images of the encapsulated liposomes comprising the derivative of curcumin. Figure 3 is a graph showing the number of encapsulated liposomes comprising the derivative of curcumin (written as “No. of particles”) against the size of the encapsulated liposomes in pm. The graph shows that the average mean size of the encapsulated liposomes is around 1.39 pm. Figure 4 shows a transmission electron microscope image of a liposome comprising the derivative of curcumin. The liposomal type shown is multilamellar vesicle (MLV) with several lamellar phase lipid bilayers. Figure 5 shows a Fourier-transform infrared spectroscopy (FTIR) spectrum including curcumin and the encapsulated liposome comprising a derivative of curcumin. FTIR spectrum analysis was used as a fast and non-destructive technique to evaluate curcumin and liposomes comprising the derivative of curcumin. According to the spectrum shown in Figure 5, when liposomes comprising the derivative of curcumin are encapsulated in betacyclodextrin, the wavelength of the peaks change as the aryl groups are trapped in the beta-cyclodextrin hydrophobic central cavity. An increase in electron cloud density leads to a change in wavenumber (cm’1). Figure 6 shows the intensity of microencapsulation liposome-curcumin, where the diameters of nanoparticles are about 1000nm (Eff. Diam. (nm) = 1039.83). Figure 7 shows that the phenolic group of curcumin in range 9pmm has been converted to ester groups. Figure 8 shows shows the measurement of the encapsulation efficiency (EE%) by UV absorption. A quantity of powdered encapsulated liposome comprising the derivative of curcumin is dissolved in ethanol, and the UV absorbtion is measured with the absorption device (see Figure 8a). Then, the same quantity of powdered encapsulated liposome comprising the derivative of curcumin is added to distilled water and centrifuged at 3000 rpm for 5 minutes. The resulting solution is passed through Whatman paper and the UV absorbtion is measured with the absorption device (see Figure 8b). The encapsulation efficiency (EE%) is provided by the following equation: __ CURCUMIN ENCAPSULATED * . „„ EE = -------------------- 100 TOTAL AMOUNT OF CURCUMIN curcumin encapsulated = curcumin total - curcumin filter EE = (((3.9-0.4) / 3.9)*100) = 89 / 91% Example Place a three-necked in an oil bath and connect one end of the flask to argon gas and leave the other open for gas to exit, ensuring the environment becomes oxygen-free. Add 33% w / w of Tween 80 (RTM) and 14% w / w of polyethylene glycol (PEG400) to the flask, and set the stirrer to 200 RPM to thoroughly mix the substances. Then, set the heater temperature to 50°C and add 10% w / w of MCT (medium-chain triglycerides) to the flask. Continue stirring until the materials together have thoroughly mixed. Divide the curcumin into three equal parts, each comprising 4% w / w. Add each part step by step to the flask while simultaneously increasing the heater temperature. At the same time as adding the curcumin, optionally add ethanol or acetone to the reaction, increasing the reaction rate. Raise the reaction temperature to 100°C and stir at 400 RPM for 2 hours. When the solution's colour has turned dark red, add 10% w / w of acetic acid and seal the flask. Stir at 90°C for 1 hour. Remove the ethanol from the reaction medium after a dark magenta colour appears in the solution. After removing the ethanol (or any organic solvent), adjust the temperature of the solution to 45°C, then add 1.5% w / w phospholipon® 80H to the solution. Next, place the mixture on a stirrer at 1250 rpm for 2 hours. During the reaction, raise the temperature to 80°C and then gradually lower it again to facilitate the liposomal process. At this point, the dark magenta colour of the solution will change to yellow. Encapsulation 2.75 g of beta-cyclodextrin was added to 100 mL of acidic environment with a pH of 3.5 at 35°C. The temperature was then lowered to 10°C. Then, slowly add the liposomal solution to the beta-cyclodextrin solution. The temperature should be maintained at between 25°C and 30°C. Next, homogenize the mixture using a homogenizer at 10,000 rpm for 1 hour. Finally, to prevent aggregation, Aerosol 200 is used. It should be appreciated that in the above description of exemplary embodiments, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. While some embodiments described herein include some, but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the disclosure, and form different embodiments, as would be understood by the skilled person. For example, in the following claims, any of the claimed embodiments can be used in any combination. Thus, while certain embodiments have been described, it will be appreciated that other and further modifications may be made thereto without departing from the spirit of the disclosure, and it is intended to cover all such modifications, enhancements, and other 5 implementations, which fall within the true spirit and scope of this disclosure. To the maximum extent permitted by law, the scope of this disclosure is to be determined by the broadest permissible interpretation of the following claims and shall not be restricted or limited by the foregoing detailed description. 10 While various implementations of the disclosure have been described, it will be readily apparent to the skilled person that many more implementations are possible within the scope of the disclosure.

Claims

1. A method of forming a liposome comprising a derivative of curcumin, comprising:a first step, in which curcumin is reacted with a fatty acid ester comprising a medium chain triglyceride to form a derivative of curcumin, wherein the reaction is carried out at an elevated temperature and the reaction medium comprises a surfactant and an acid; anda second step, in which the derivative of curcumin is combined with a phospholipid to form a liposome comprising the derivative of curcumin, and wherein the derivative of curcumin is not isolated from the reaction medium following the first step.

2. A method according to claim 1, wherein the medium chain triglyceride comprises amixture of different medium chain triglycerides.

3. A method according to claim 2, wherein the medium chain triglyceride comprises amixture of different medium chain triglycerides derived from fatty acids caprylic acid and capric acid.

4. A method according to any preceding claim, wherein organic solvents are not used in the second step.

5. A method according to any preceding claim, wherein any organic solvents which are used in the first step are removed prior to the second step.

6. A method according to any preceding claim, wherein the fatty acid ester reacts at an oxygen atom of curcumin.

7. A method according to any preceding claim, wherein the fatty acid ester reacts at an aromatic oxygen atom of curcumin.

8. A method according to any preceding claim, wherein the fatty acid ester reacts at the phenolic group of curcumin.

9. A method according to any preceding claim, wherein the w / w ratio of curcumin to fatty acid ester in the first step is 1.2:1.

10. A method according to any preceding claim, wherein the w / w ratio of the derivative of curcumin to the liposome forming compound in the second step is 8:1.

11. A method according to any preceding claim, comprising the following further step:a third step, in which the liposome comprising the derivative of curcumin is combined with a polymer to form an encapsulated liposome comprising the derivative of curcumin.

12. A method according to claim 11, wherein the polymer is an oligosaccharide.

13. A method according to claim 11 or 12, wherein the encapsulated liposomes comprising the derivative of curcumin are formed into a powder.

14. A method according to any one of claims 11 to 13, wherein the third step is carried out in acidic solution.

15. A method according to claim 14, wherein the acidic solution has a pH of about 3.5.OJ 16. A method according to any one of claims 12 to 15, wherein the encapsulated liposomesCM CMcomprising the derivative of curcumin are dried with a spray dryer.

17. A method according to any preceding claim, wherein the first, second and / or third step are carried out in an inert atmosphere.

18. A liposome comprising the derivative of curcumin, prepared by the method of any one of claims 1 to 11.

19. An encapsulated liposome comprising the derivative of curcumin, prepared by the method of any one of claims 12 to 17.

20. The encapsulated liposome comprising the derivative of curcumin according to claim 19, which is in the form of a powder.

21. The encapsulated liposome according to claim 19 or 20, wherein the average diameter of an encapsulated liposome is between 1 and 2 pm.

22. A pharmaceutically acceptable composition, comprising the liposome comprising the derivative of curcumin according to claim 18, or the encapsulated liposome comprising the derivative of curcumin according to any one of claims 19 to 21.CM CM23. The liposome comprising the derivative of curcumin according to claim 18, or the encapsulated liposome comprising the derivative of curcumin according to any one of claims 19 to 21, or the pharmaceutically acceptable composition according to claim 22, for use as a medicament.

24. The liposome comprising the derivative of curcumin according to claim 18, or the encapsulated liposome comprising the derivative of curcumin according to any one of claims 19 to 21, or the pharmaceutically acceptable composition according to claim 22, for use as a food or supplement.

25. A food or supplement comprising the liposome comprising the derivative of curcumin according to claim 18, or the encapsulated liposome comprising the derivative of curcumin according to any one of claims 19 to 21.

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