Prebiotic composite scaffold

Abstract

The invention provides a prebiotic composite scaffold comprising at least one prebiotic compound and at least one gastrointestinal-resistant biopolymer wherein the gastrointestinal-resistant biopolymer comprises at least one gellan gum or a derivative thereof.

Description

[0001] PREBIOTIC COMPOSITE SCAFFOLD

[0002] Technical Field of the Invention

[0003] The present invention relates to a prebiotic composite scaffold, a method of preparing the prebiotic composite scaffold, a food product, a food supplement and a nutraceutical comprising the prebiotic composite scaffold, and uses thereof.

[0004] Background to the Invention

[0005] Prebiotics are compounds, typically non-digestible food ingredients, which stimulate the growth of beneficial microorganisms in the intestines. A problem with known prebiotics is that they may not provide suitable food and space for beneficial microorganisms or bacteria to grow. A further problem with known prebiotics is that they may not be gastric or pH resistant and therefore may breakdown or dissolve before they reach the desired location of the lower gastrointestinal tract.

[0006] It would therefore be advantageous to provide a prebiotic composite scaffold with suitable food and suitable space for beneficial microorganisms or bacteria to grow. Suitable space provides an environment to enable the beneficial bacteria to grow on.

[0007] It would also be advantageous to provide a prebiotic composite scaffold with improved gastric resistance and improved pH stability to successfully deliver a prebiotic compound to the lower gastrointestinal tract to promote growth of beneficial bacteria, such as mucosal adherent bacteria, in the colon by providing sufficient food and space for bacterial growth. It would furthermore be advantageous to provide a prebiotic composite scaffold which can provide a food and space for mucosal adherent bacteria to grow such that the bacteria can grow on and be supported by the scaffold.

[0008] It would be advantageous to provide a prebiotic composite scaffold which can be used as a treatment for individuals with diseases associated with intestinal microbiome dysbiosis, such as inflammatory bowel disease, by successfully promoting the growth of desired bacteria in the colon which may be in low abundance prior to the treatment.

[0009] It would be advantageous to provide a prebiotic composite scaffold which specifically targets the growth of recognised beneficial bacteria to provide a personalised or customisable approach to microbiome modulation.

[0010] It is an aim of embodiments of the invention to overcome one or more problems of the prior art, whether expressly disclosed herein or not.

[0011] Summary of the Invention

[0012] According to a first aspect of the invention there is provided a prebiotic composite scaffold comprising at least one prebiotic compound and at least one gastrointestinal-resistant biopolymer wherein the gastrointestinal-resistant biopolymer comprises at least one gellan gum or a derivative thereof.

[0013] The composite scaffold may be a microcomposite scaffold.

[0014] By “microcomposite” we mean microscale composite material comprising one or more components. By “scaffold” we mean a 3D structure in which molecules are linked. The scaffold may comprise a structure to which bacteria and microflora may contact, infiltrate and / or adhere in the gut. In some embodiments, the prebiotic composite scaffold comprises a 3D structure in which biopolymers are linked. In preferred embodiments, the prebiotic composite scaffold comprises a 3D structure in which the or each gastrointestinal-resistant biopolymer is linked. The molecules or biopolymers may be linked covalently or ionically.

[0015] A “gastrointestinal-resistant biopolymer” is taken to be a biopolymer with resistance to the gastrointestinal environment. The gastrointestinal environment may comprise digestive enzymes, changes in pH and gastrointestinal solutes and chemicals. In some embodiments the or each gastrointestinal-resistant biopolymer is a gastrointestinal-inert biopolymer. In some embodiments the or each gastrointestinal- resistant biopolymer remains at least partially intact following exposure to the gastrointestinal environment. In some embodiments the or each gastrointestinal- resistant biopolymer remains substantially intact following exposure to the gastrointestinal environment such that it reaches the small intestine and / or the large intestine substantially intact. In some embodiments the or each gastrointestinal-resistant biopolymer thereof remains substantially intact following exposure to the gastrointestinal environment such that it reaches the colon substantially intact. In some embodiments the or each gastrointestinal-resistant biopolymer thereof remains substantially intact but may change in diameter or swell following exposure to the gastrointestinal environment. The or each gastrointestinal-resistant biopolymer may itself act as or be a prebiotic. The or each gastrointestinal-resistant biopolymer may form a scaffold. The gastrointestinal-resistant biopolymer scaffold may be advantageous because it may provide space for beneficial bacteria, such as mucosal bacteria, to grow on.

[0016] The or each prebiotic compound may comprise any compound which may act as a food for bacteria in use.

[0017] The prebiotic composite scaffold of the invention may be advantageous because the scaffold may provide additional space for desired bacteria to grow, and the presence of the prebiotic compound additionally provides food for the bacteria to grow. The prebiotic composite scaffold of the invention may be advantageous because gellan gum or a derivative thereof is a gastrointestinal-resistant biopolymer with desirable resistance to gastric fluids, and therefore the prebiotic composite scaffold may be resistant to disintegration throughout the stomach and small intestine to successfully deliver the or each prebiotic to the colon and to successfully provide a substantially intact scaffold to support the growth of bacterial in the colon and / or the small intestine and / or the large intestine. The prebiotic composite scaffold may therefore positively impact microbial communities in the colon and / or the small intestine and / or the large intestine, in particular by providing a growth support for mucosal-adherent bacteria.

[0018] The prebiotic composite scaffold may comprise a gel. In some embodiments the gastrointestinal-resistant biopolymer may be in the form of a gel or a gel matrix. In preferred embodiments the prebiotic composite scaffold comprises at least one gastrointestinal-resistant biopolymer wherein the or each gastrointestinal-resistant biopolymer is ionically linked to form a gel or a gel matrix. This embodiment may be advantageous because it may provide a prebiotic composite scaffold which is inert to degradation via gastrointestinal transit such that it provides a substantially intact prebiotic composite scaffold in the colon, small intestine and / or large intestine.

[0019] The prebiotic composite scaffold may comprise at least 2, 3 or at least 4 prebiotic compounds.

[0020] The prebiotic compound may comprise at least one polysaccharide. Each polysaccharide may be selected from the group consisting of: cellulose, an alginate, xanthan gum, hemicellulose, pectin, dextrose, chitin, chitosan, inulin, resistant starch, glycogen, heparin, peptidoglycan, locust bean gum, tragacanth gum, mucins, N- glycans, O-glycans, glycoproteins, dextran, gellan gum, or any combination thereof. The cellulose may comprise a cellulose derivative. The cellulose may comprise a methyl cellulose or an ethyl cellulose. The prebiotic may comprise carboxymethyl cellulose. The prebiotic may comprise sodium alginate. The prebiotic compound may comprise an oligosaccharide. The prebiotic compound may comprise a fructooligosaccharide or a galacto-oligosaccharide. The chitosan may comprise low molecular weight chitosan. The low molecular weight chitosan may comprise a molecular weight of approximately between 50,000 and 190,000 Da based on the viscosity.

[0021] The gellan gum may comprise a linear tetrasaccharide repeating unit of D- glucose, D-glucuronic acid, D-glucose, and L-rhamnose as shown below: The gellan gum may have the general structure [D-Glc(pi^4)D-

[0022] GlcA(pi^4)D-Glc(pi^4)L-Rha(al^3)]n as shown below:

[0023] The gellan gum may comprise high acyl gellan gum. High acyl gellan gum may have the general structure as shown below:

[0024] Gellan gum derivatives may include alkyl-, acrylate- and amine-derivatised gellan gums, for example.

[0025] The prebiotic composite scaffold may comprise at least 0.1 % w / v gellan gum and / or derivative thereof, in total. The prebiotic composite scaffold may comprise at least 0.2 % w / v, 0.4 % w / v, 0.5 % w / v, 0.6 % w / v, 0.7 % w / v, 0.8 % w / v, 0.9 % w / v or at least 1 % w / v gellan gum and / or derivative thereof, in total. The prebiotic composite scaffold may comprise no more than 5 % w / v gellan gum and / or derivative thereof, in total. The prebiotic composite scaffold may comprise no more than 4 % w / v, 3.5 % w / v, 3 % w / v, 2.5 % w / v, or no more than 2 % w / v gellan gum and / or derivative thereof, in total. The prebiotic composite scaffold may comprise between 0.1 and 5 %\NN gellan gum and / or derivative thereof, in total. The prebiotic composite scaffold may comprise between 0.2 and 4 % w / v, 0.4 and 3.5 % w / v, 0.5 and 2.5 % w / v, 0.6 and 2.5 % w / v, 0.7 and 2.5 % w / v, 0.8 and 2.5 % w / v, 0.9 and 2.5 % w / v, 1 and 2.5 % w / v or between 1 and 2 % w / v gellan gum and / or derivative thereof, in total.

[0026] The prebiotic composite scaffold may comprise one or more further gastrointestinal-resistant biopolymer, in addition to at least one gellan gum or derivative thereof. The at least one further gastrointestinal-resistant biopolymer may comprise urea. The at least one further gastrointestinal-resistant biopolymer may comprise at least 0.1 % w / v urea The at least one further gastrointestinal-resistant biopolymer may comprise at least 0.5 % w / v, 1 % w / v, 1.5 % w / v, or at least 2 % w / v urea. The at least one gastrointestinal-resistant biopolymer may comprise no more than 4 % w / v, 3.5 % w / v, 3 % w / v or no more than 2.5 % w / v urea. The at least one further gastrointestinal- resistant biopolymer may comprise between 0.5 and 4 % w / v, 1 and 3.5 % w / v, 1.5 and 3 % w / v or between 2 and 2.5 % w / v urea. This embodiment may be advantageous because the compounds may have gastric-resistant properties whilst also having pH- dependent release properties within the small and large intestine.

[0027] The total concentration the gastrointestinal-resistant biopolymer(s) in the composite scaffold may be at least 0.1 % w / v. The total concentration of the gastrointestinal-resistant biopolymer(s) in the composite scaffold may be at least 0.2 % w / v, 0.4 % w / v, 0.5 % w / v, 0.6 % w / v, 0.7 % w / v, 0.8 % w / v, 0.9 % w / v, or at least 1 % w / v. The total concentration of the gastrointestinal-resistant biopolymer(s) in the composite scaffold may be no more than 5 % w / v. The total concentration of the gastrointestinal-resistant biopolymer(s) in the composite scaffold may be no more than 4.5 % w / v, 4 % w / v, or no more than 3.5 % w / v. The total concentration of the gastrointestinal-resistant biopolymer(s) in the composite scaffold may be between 0.1 and 5 % w / v, 0.1 and 4.5 % w / v, 0.1 and 4 % w / v, 0.2 and 4 % w / v, 0.5 and 4 % w / v, 0.5 and 4 % w / v, 0.7 and 4 % w / v, 0.8 and 3.5 % w / v, 0.9 and 3.5 % w / v, or between 1 % w / v and 3.5 % w / v. This embodiment may be advantageous because it may provide a prebiotic composite scaffold with increased resistance to dissolution in the small intestine.

[0028] The prebiotic composite scaffold may comprise at least 0.01 % w / v prebiotic compound. The prebiotic composite scaffold may comprise at least 0.02 % w / v, 0.05 % w / v, 0.1 % w / v, 0.2 % w / v, 0.4 % w / v, 0.5 % w / v, 0.6 % w / v, 0.7 % w / v, 0.8 % w / v, 0.9 % w / v or at least 1 % w / v prebiotic compound. The prebiotic composite scaffold may comprise no more than 5 % w / v prebiotic compound. The prebiotic composite scaffold may comprise no more than 4 % w / v, 3.5 % w / v, 3 % w / v, 2.5 % w / v, or no more than 2 % w / v prebiotic compound. The prebiotic composite scaffold may comprise between 0.01 and 5 % w / v prebiotic compound. The prebiotic composite scaffold may comprise between 0.02 and 4 % w / v, 0.05 and 4 % w / v, 0.1 and 4 % w / v, 0.2 and 4 % w / v, 0.4 and 3.5 % w / v, 0.5 and 2.5 % w / v, 0.6 and 2.5 % w / v, 0.7 and 2.5 % w / v, 0.8 and 2.5 % w / v, 0.9 and 2.5 % w / v, 1 and 2.5 % w / v or between 1 and 2 % w / v prebiotic compound.

[0029] The ratio of w / v of the or each prebiotic and the w / v of the total amount of gastrointestinal-resistant biopolymer(s) may be between 50:1 and 1 :50. The ratio of w / v of the or each prebiotic and the w / v of the total amount of gastrointestinal-resistant biopolymer(s) may be between 45:1 and 1:45, or 40:1 and 1:40, 30:1 and 1:30, 30:1 and 1:20, or between 30:1 and 1:10. In some embodiments the ratio of w / v of the or each prebiotic and the w / v of the total amount of gastrointestinal-resistant biopolymer(s) is between 1:1 and 1:50, or 1:1 and 1:40, or 1:1 and 1:30, or 1:1 and 1:20, or 1:1 and 1:10, or 1:1 and 1:5, or 1:1 and 1:4, or 1:1 and 1:3, or between 1:1 and 1:2.

[0030] The prebiotic composite scaffold may comprise a prebiotic compound comprising cellulose or a derivative thereof, and at least one gellan gum and / or a derivative thereof. The w / v ratio of cellulose and / or derivative thereof and gellan gum and / or derivative thereof may be between 5:1 and 1:5. The w / v ratio of the cellulose and / or derivative thereof and gellan gum and / or derivative thereof may be between 4:1 and 1:4, 3:1 and 1:3, 2:1 and 1:2, or between 1:1 and 1:2. The w / v ratio of the cellulose and / or derivative thereof and gellan gum and / or derivative thereof may be approximately 1:2.

[0031] The prebiotic composite scaffold may comprise between 0.2 and 1 % w / v cellulose and / or derivative thereof, and between 0.5 and 4 % w / v gellan gum and / or derivative thereof. The prebiotic composite scaffold may comprise between 0.3 and 0.8 % w / v, or 0.4 and 0.7 % w / v or between 0.4 and 0.6 % w / v cellulose and / or derivative thereof, and between 0.5 and 4 % w / v, 0.5 and 3 % w / v, 0.5 and 2 % w / v or between 0.5 and 1.5 % w / v gellan gum and / or derivative thereof. The prebiotic composite scaffold may comprise approximately 0.5 % w / v cellulose and / or derivative thereof, and approximately 1 % w / v gellan gum and / or derivative thereof. The prebiotic composite scaffold may comprise a prebiotic compound comprising carboxymethylcellulose, and gellan gum and / or derivative thereof. The w / v ratio of the carboxymethylcellulose and gellan gum may be between 5:1 and 1:5. The w / v ratio of the carboxymethylcellulose and gellan gum and / or a derivative thereof may be between 4:1 and 1:4, 3:1 and 1:3, 2:1 and 1:2, or between 1:1 and 1:2. The w / v ratio of the carboxymethylcellulose and gellan gum and / or derivative thereof may be approximately 1:2. This embodiment may be advantageous because the prebiotic composite scaffold may persist within the colon and support the growth of mucosal- associated bacteria such as Akkermansia muciniphila, which may alter microbial diversity within the intestinal microbiome.

[0032] The prebiotic composite scaffold may comprise between 0.2 and 1 % w / v carboxymethylcellulose, and between 0.5 and 4 % w / v gellan gum and / or derivative thereof. The prebiotic composite scaffold may comprise between 0.3 and 0.8 % w / v, or 0.4 and 0.7 % w / v or between 0.4 and 0.6 % w / v carboxymethylcellulose, and between 0.5 and 4 % w / v, 0.5 and 3 % w / v, 0.5 and 2 % w / v or between 0.5 and 1.5 % w / v gellan gum and / or derivative thereof. The prebiotic composite scaffold may comprise approximately 0.5 % w / v carboxymethylcellulose, and approximately 1 % w / v gellan gum and / or derivative thereof.

[0033] The prebiotic composite scaffold may comprise a prebiotic compound comprising xanthan gum, and gellan gum and / or derivative thereof. The w / v ratio of the gellan gum and / or derivative thereof and xanthan gum may be between 5:1 and 1:5. The w / v ratio of the gellan gum and / or derivative thereof and xanthan gum may be between 4:1 and 1:4, 3:1 and 1:3, 2:1 and 1:2, or between 2:1 and 1:1. The w / v ratio of the gellan gum and / or derivative thereof and xanthan gum may be approximately 2:1, approximately 1.5:1 or approximately 1.3:1.

[0034] The prebiotic composite scaffold may comprise between 0.2 and 1 % w / v xanthan gum, and between 0.5 and 2 % w / v gellan gum and / or derivative thereof. The prebiotic composite scaffold may comprise between 0.3 and 0.8 % w / v, or 0.4 and 0.8 % w / v or between 0.5 and 0.8 % w / v xanthan gum, and between 0.5 and 1.5 % w / v gellan gum and / or derivative thereof. The prebiotic composite scaffold may comprise approximately 0.75 % w / v xanthan gum, and approximately 1 % w / v gellan gum and / or derivative thereof.

[0035] The prebiotic composite scaffold may comprise a prebiotic compound comprising sodium alginate, and gellan gum and / or derivative thereof. The w / v ratio of the sodium alginate and gellan gum and / or derivative thereof may be between 50: 1 and 1:5. The w / v ratio of the sodium alginate and gellan gum and / or derivative thereof may be between 45:1 and 1:5, 40:1 and 1:1, 35:1 and 10:1, 35:1 and 20:1 or between 30:1 and 25:1. The w / v ratio of the sodium alginate and gellan gum and / or derivative thereof may be approximately 30:1.

[0036] The prebiotic composite scaffold may comprise between 1 and 4 % w / v sodium alginate, and between 0.1 and 1 % w / v gellan gum and / or derivative thereof. The prebiotic composite scaffold may comprise between 2 and 4 % w / v, or between 2.5 and 3.5 % w / v sodium alginate, and between 0.1 and 0.8 % w / v, or 0.1 and 0.5 % w / v, or between 0.1 and 0.3 % w / v gellan gum and / or derivative thereof. The prebiotic composite scaffold may comprise approximately 3 % w / v sodium alginate, and approximately 0.1 % w / v gellan gum and / or derivative thereof. The prebiotic composite scaffold may comprise a homogenous mixture comprising the or each prebiotic compound and the or each gastrointestinal-resistant biopolymer wherein the gastrointestinal-resistant biopolymer comprises at least one gellan gum and / or derivative thereof.

[0037] The prebiotic composite scaffold may comprise the or each prebiotic compound coated onto the or each gastrointestinal-resistant biopolymer wherein the gastrointestinal-resistant biopolymer comprises at least one gellan gum and / or derivative thereof. The or each prebiotic compound may be continuously or discontinuously coated onto the gastrointestinal-resistant biopolymer. This embodiment may be advantageous because the coated prebiotic compound could be beneficial for mucosal bacteria and the gastrointestinal-resistant biopolymer may provide a suitable support for the bacterial to grow on.

[0038] The prebiotic composite scaffold may comprise the or each prebiotic compound at least partially encapsulated by the or each gastrointestinal-resistant biopolymer wherein the gastrointestinal-resistant biopolymer comprises at least one gellan gum and / or derivative thereof. The prebiotic composite scaffold may comprise the or each prebiotic compound fully encapsulated by the or each gastrointestinal-resistant biopolymer wherein the gastrointestinal-resistant biopolymer comprises at least one gellan gum and / or derivative thereof. The prebiotic composite scaffold may comprise the or each prebiotic compound fully encapsulated by a gel network comprising the or each gastrointestinal-resistant biopolymer wherein the gastrointestinal-resistant biopolymer comprises at least one gellan gum and / or derivative thereof. This embodiment may be advantageous because the encapsulated prebiotic compound may be released to be accessed by luminal bacteria. The or each prebiotic compound may comprise continuous or discontinuous material encapsulated by the gastrointestinal- resistant biopolymer.

[0039] The prebiotic composite scaffold may comprise a diameter of at least 50 pm. The prebiotic composite scaffold may comprise a diameter of at least 60 pm pm, 70 pm, 80 pm, 90 pm, or at least 100 pm. The prebiotic composite scaffold may comprise a diameter of no more than 2000 pm. The prebiotic composite scaffold may comprise a diameter of no more than 1900 pm, 1800 pm, 1600 pm, 1500 pm, 1200 pm, 1000 pm, 800 pm, 600 pm or no more than 500 pm. The prebiotic composite scaffold may comprise a diameter of between 50 pm and 1000 pm. The prebiotic composite scaffold may comprise a diameter of between 60 pm and 1900 pm, 70 pm and 1800 pm, 80 pm and 1600 pm, 90 pm and 1500 pm, 100 pm and 1400 pm, 100 pm and 1200 pm, 100 pm and 1000 pm, 100 pm and 800 pm, 100 pm and 600 pm, or between 100 pm and 500 pm. This embodiment may be advantageous because it may provide a prebiotic composite scaffold with increased resistance to dissolution in the small intestine.

[0040] In some embodiments the prebiotic composite scaffold may comprise a diameter of at least 150 pm. The prebiotic composite scaffold may comprise a diameter of at least 200 pm pm, 250 pm, 300 pm, 350 pm, 400 pm, 450 pm, or at least 500 pm. The prebiotic composite scaffold may comprise a diameter of no more than 2000 pm. The prebiotic composite scaffold may comprise a diameter of no more than 1900 pm, 1800 pm, 1700 pm, 1600 pm, or no more than 1500 pm. The prebiotic composite scaffold may comprise a diameter of between 50 pm and 1000 pm. The prebiotic composite scaffold may comprise a diameter of between 150 pm and 2000 pm, 200 pm and 1900 pm, 250 pm and 1800 pm, 300 pm and 1700 pm, 350 pm and 1600 pm, 400 pm and 1600 pm, or between 500 pm and 1500 pm. This embodiment may be advantageous because it may provide a larger prebiotic composite scaffold with increased resistance to dissolution in the small intestine.

[0041] The prebiotic composite scaffold may be in the form of a tablet, a capsule, a pill, a powder, a lozenge, or a potable solution.

[0042] According to a second aspect of the invention there is provided a method of preparing a prebiotic composite scaffold of the first aspect of the invention comprising prilling or ionic gelation of a solution comprising at least one gastrointestinal-resistant biopolymer and at least one prebiotic compound, wherein the gastrointestinal-resistant biopolymer comprises at least one gellan gum or a derivative thereof.

[0043] Ionic gelation may also be called ionotropic gelation. Ionic gelation comprises aggregation of polymers with multivalent counter ions.

[0044] Prilling is an encapsulation method that turns a liquid stream into droplets by applying aerodynamic -based atomisation.

[0045] The prilling or ionic gelation may comprise spraying the solution comprising the at least one gastrointestinal-resistant biopolymer and the at least one prebiotic compound from a nozzle orifice. The nozzle orifice may comprise a diameter of at least 200 pm. The nozzle orifice may comprise a diameter of at least 250 pm, 300 pm, or at least 350 pm. The nozzle orifice may comprise a diameter of no more than 1500 pm. The nozzle orifice may comprise a diameter of no more than 1400 pm, 1300 pm, 1200 pm, 1100 pm, or no more than 1000 pm. The nozzle orifice may comprise a diameter of between 200 pm and 1500 pm. The nozzle orifice may comprise a diameter of between 250 pm and 1400 pm, 300 pm and 1300 pm, 300 pm and 1200 pm, 300 pm and 1100 pm, or between 350 pm and 1000 pm. In some embodiments the nozzle orifice may comprise a diameter of 350 pm, 500 pm or 1000 pm.

[0046] The prilling or ionic gelation may comprise spraying the solution comprising the at least one gastrointestinal-resistant biopolymer and the at least one prebiotic compound at a flow rate of at least 1 mL / min. The prilling or ionic gelation may comprise spraying the solution at a flow rate of at least 1.5 mL / min, 2 mL / min, 2.5 mL / min, or at least 3 mL / min. The prilling or ionic gelation may comprise spraying the solution at a flow rate of no more than 6 mL / min. The prilling or ionic gelation may comprise spraying the solution at a flow rate of no more than 5 mL / min, 4 mL / min, or no more than 3.5 mL / min. The prilling may comprise spraying the solution at a flow rate of between 1 and 5 mL / min, 2 and 4 mL / min, or between 3 and 3.5 mL / min.

[0047] The prilling or ionic gelation may comprise spraying the solution comprising at the least one gastrointestinal-resistant biopolymer and the at least one prebiotic compound at a pressure of at least 20 mbar. The prilling or ionic gelation may comprise spraying the solution at a pressure of at least 30 mbar, 40 mbar or at least 50 mbar. The prilling or ionic gelation may comprise spraying the solution at a pressure of no more than 200 mbar. The prilling or ionic gelation may comprise spraying the solution at a pressure of no more than 180 mbar, 160 mbar, or no more than 150 mbar. The prilling or ionic gelation may comprise spraying the solution at a pressure of between 20 and 200 mbar, 30 and 180 mbar, 40 and 160 mbar or between 50 and 150 mbar.

[0048] The solution may comprise at least 0.1 % w / v urea The solution may comprise at least 0.5 % w / v, 1 % w / v, 1.5 % w / v, or at least 2 % w / v urea. The solution may comprise no more than 4 % w / v, 3.5 % w / v, 3 % w / v or no more than 2.5 % w / v urea. The solution may comprise between 0.5 and 4 % w / v, 1 and 3.5 % w / v, 1.5 and 3 % w / v or between 2 and 2.5 % w / v urea. The solution may comprise urea during prilling or ionic gelation and the urea may then diffuse out of the resulting prebiotic composite scaffold after the prilling or ionic gelation. This embodiment may be advantageous because the compounds may keep the solution at a desirable viscosity such that the solution is suitable for prilling or ionic gelation to form the prebiotic composite scaffold.

[0049] According to a third aspect of the invention there is provided a food product comprising a prebiotic composite scaffold comprising at least one prebiotic compound and at least one gastrointestinal-resistant biopolymer wherein the gastrointestinal- resistant biopolymer comprises at least one gellan gum or a derivative thereof.

[0050] According to a fourth aspect of the invention there is provided a food supplement comprising a prebiotic composite scaffold comprising at least one prebiotic compound and at least one gastrointestinal-resistant biopolymer wherein the gastrointestinal-resistant biopolymer comprises at least one gellan gum or a derivative thereof.

[0051] According to a fifth aspect of the invention there is provided a nutraceutical comprising a prebiotic composite scaffold comprising at least one prebiotic compound and at least one gastrointestinal-resistant biopolymer wherein the gastrointestinal- resistant biopolymer comprises at least one gellan gum or a derivative thereof.

[0052] According to a sixth aspect of the invention there is provided a prebiotic composite scaffold comprising at least one prebiotic compound and at least one gastrointestinal-resistant biopolymer wherein the gastrointestinal-resistant biopolymer comprises at least one gellan gum or a derivative thereof, for use in promoting the growth of mucosal-associated bacteria within a colonic microbiome.

[0053] According to a seventh aspect of the invention there is provided a prebiotic composite scaffold comprising at least one prebiotic compound and at least one gastrointestinal-resistant biopolymer wherein the gastrointestinal-resistant biopolymer comprises at least one gellan gum or a derivative thereof, for use in the treatment of a disease associated with intestinal microbiome dysbiosis.

[0054] The disease associated with intestinal microbiome dysbiosis may be selected from the group consisting of: inflammatory bowel disease, inflammatory bowel syndrome, diabetes, obesity, cancer such as colorectal cancer, small intestinal bacterial overgrowth (SIBO), and allergic disorders. The inflammatory bowel disease may be Crohn’s disease or ulcerative colitis.

[0055] The prebiotic composite scaffold of the third, fourth, fifth, sixth or seventh aspects of the invention may be according to any embodiment of the first aspect of the invention.

[0056] The prebiotic composite scaffold of the third, fourth, fifth, sixth or seventh aspects of the invention may be prepared according to any embodiment of the second aspect of the invention.

[0057] Detailed Description of the Invention In order that the invention may be more clearly understood embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings, of which:

[0058] Figure 1 is a graph to show the change in diameter of a control gellan gum microcomposite (GG), an inventive gellan gum and xanthan gum prebiotic microcomposite scaffold (GGXG) and an inventive gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold (GGCMC), before exposure to simulated gastric and intestinal fluids (pre-treatment) and after exposure to simulated gastric fluid (Post-SGF) and the simulated intestinal fluid (Post-SIF).

[0059] Figure 2 shows graphs of the release profiles of the gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold (GGCMC), gellan gum and xanthan gum prebiotic microcomposite scaffold (GGXG) and a control gellan gum (GG) only compound in simulated gastric fluid (Figure 2 A) and simulated intestinal fluid (Figure 2B).

[0060] Figure 3 A is a graph showing the bacterial growth of Akkermansia muciniphilia on exposure to a gellan gum, carboxymethyl cellulose or media only after 48 hours.

[0061] Figure 3B is a graph showing the bacterial growth of Akkermansia muciniphilia on exposure to a gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold (GGCMC) and a control sample which does not comprise a prebiotic microcomposite scaffold after 0 hours, 8 hours and 24 hours. Figure 4 is a graph showing the diameter of the gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold before exposure to the MIMic (pre-treatment), after stomach treatment, after small intestinal treatment and after colon treatment. Figure 5 is a graph showing the concentration of short chain fatty acids (SCFA) before and after administration of the gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold (GGCMC).

[0062] A series of prebiotic composite scaffolds according to the first aspect of the invention comprising at least one prebiotic compound and at least one gastrointestinal- resistant biopolymer wherein the gastrointestinal -resistant biopolymer comprises gellan gum were prepared and are summarised in table 1. The prebiotic composite scaffolds are prebiotic microcomposite scaffolds.

[0063] Table 1

[0064] The sodium alginate was Manugel GHB supplied by FMC Biopolymer / Dupont

[0065] (Drammen, Norway). Embodiment 1 comprises carboxymethyl cellulose encapsulated within gellan gum. Embodiment 2 comprises xanthan encapsulated within gellan gum. Embodiment 3 comprises gellan gum encapsulated within sodium alginate.

[0066] The diameter of the gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold comprised a diameter of approximately 800 pm (803 pm) as measured by light microscope.

[0067] The diameter of the gellan gum and xanthan gum prebiotic microcomposite scaffold comprised a diameter of approximately 650 pm as measured by light microscope.

[0068] Method of preparation

[0069] The prebiotic microcomposite scaffolds were prepared by prilling using a Var- J30 encapsulation unit fitted with a pressure sensor and control cabinet to control flowrate pressure, syringe pump, changeable nozzles with 350, 500 and 1000 pm orifice sizes, and silicon pump tubing used for biomaterial feeds.

[0070] A solution comprising the prebiotic compound and the gastrointestinal-resistant biopolymer in warm deionised water was sprayed through a nozzle head into a stirred hardening solution comprising ice-cold aqueous CaCh (2 %w / v) in deionised water. It is understood that a hardening solution comprising other divalent metal cations could be used. The prebiotic microcomposite scaffolds were then conditioned within the hardening solution for 15 minutes before being processed for further experimentation. Testing prebiotic microcomposite scaffolds in Simulated Gastric and Intestinal fluid

[0071] Prebiotic microcomposite scaffolds were prepared as described with the addition of red fluorescent beads at a concentration of 0.08 % (w / v) to enable the impact of simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) on the prebiotic microcomposite scaffolds. The composition of the simulated gastric fluid and simulated intestinal fluid is provided in table 2.

[0072] Table 2

[0073] For each prebiotic microcomposite scaffold population produced, a total of 6 mL prebiotic compound and the gastrointestinal-resistant biopolymer solution was sprayed to form beads, which were washed with deionised water following hardening, and resuspended in a total of 10 mL deionised water before use.

[0074] The gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold (embodiment 1) and the gellan gum and xanthan gum prebiotic microcomposite scaffold (embodiment 2) demonstrated no breakdown in simulated gastric fluid or in simulated intestinal fluid. The change in diameter of the control gellan gum microcomposite (GG), the gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold (GGCMC, embodiment 1) and the gellan gum and xanthan gum prebiotic microcomposite scaffold (GGXG, embodiment 2) before exposure to the simulated gastric and intestinal fluids (pre-treatment), after exposure to the simulated gastric fluid (Post-SGF) and after exposure to the simulated intestinal fluid (Post-SIF) is shown in figure 1. The gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold (embodiment 1) demonstrated a negligible-to-small degree of swelling in simulated gastric fluid. In comparison, there was a small decrease (7.7 %) in diameter within simulated gastric fluid or in simulated intestinal fluid of the gellan gum and xanthan gum prebiotic microcomposite scaffold (embodiment 2).

[0075] Figure 2 shows graphs of the release profiles of the gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold (GGCMC), gellan gum and xanthan gum prebiotic microcomposite scaffold (GGXG) and a control gellan gum (GG) only microcomposite in simulated gastric fluid (Figure 2A) and simulated intestinal fluid (Figure 2B). The data showed that the addition of the prebiotic compound did not negatively impact the release time of the prebiotic microcomposite scaffold and therefore the inventive prebiotic microcomposite scaffolds showed resistance to gastric fluids so they can be delivered intact to the lower gastrointestinal tract and to the colon.

[0076] Biopolymer Prebiotic Assessments

[0077] To assess bacterial growth over a time period, an automated ODeoo portable absorbance plate reader was housed within the anaerobic cabinet on a continuous orbital shaker at 400 RPM. Experiments were conducted in a 96-well plate format, containing 200 pL of media, with and without the test prebiotic microcomposite scaffold within eight replicate wells. An overnight culture of Akkermansia muciniphilia was diluted to reach an ODeoo of 0.02 within each test well; some wells were not inoculated with Akkermansia muciniphilia to monitor any background bacterial growth / ODeoo changes.

[0078] Pasteurised gellan gum and CMC biopolymers were supplemented into BHI growth media at a concentration of 0.1% (w / v) and Akkermansia muciniphilia growth was monitored over a period of 48 hours. Akkermansia muciniphilia bacteria grew as expected, following a typical sigmoidal curve and the results are shown in figure 3A. The prebiotic effect of the gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold (embodiment 1) within Akkermansia muciniphilia cultures was examined and the results are shown in figure 3B. The gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold significantly increased Akkermansia muciniphilia growth at 24 hours of conditioning by 12.8 % (p<0.001) showing a positive effect of the inventive prebiotic microcomposite scaffold on the growth of mucosal adherent bacteria.

[0079] Performance of the prebiotic microcomposite scaffold in A Model of the Intestinal Microbiome

[0080] A Model of the Intestinal Microbiome (termed MIMic hereafter) was employed for microbial community assessments in this study. The MIMic comprised three colonic bioreactors wherein the temperature of each vessel was stabilised at 37 °C and the pH was maintained between pH 6.15 - 6.8 through automated titration of HC1 (0.5 M) or NaOH (0.5 M). The complete system was maintained under a nitrogen atmosphere and constantly stirred at 180 RPM using a magnetic stirrer.

[0081] Each colonic bioreactor was fed from a small intestinal (SI) vessel. Each small intestinal vessel itself was fed from a nutrient reservoir vessel and a pancreatic feed reservoir vessel (both of which were stirred and maintained at 4 °C).

[0082] At the start of the experiment, the colonic vessels were filled with anaerobic nutrient feed prior to inoculation with donor faecal microbial communities. From each donor, 10 g of faecal material (wet weight) was mixed with an anaerobic inoculation buffer (50 mL, K2HPO4 (50.5mM), KH2PO4 (50 mM) and sodium thioglycolate (0.9 mM). The faecal material and the buffer were homogenised within a stomacher prior to centrifugation. The resultant supernatant was added to the colonic vessels which containing the nutrient feed. The colonic bioreactors were also equipped with mucin / agar covered microcosms and every 3-days half of the mucin coated microcosms were replaced with newly prepared composites.

[0083] The gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold (embodiment 1) was administered into the MIMic. Figure 4 shows the change in diameter of the gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold before exposure to the MIMic, after stomach treatment, after small intestinal treatment and after colon treatment. It was found that the gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold remained intact throughout the complete MIMic gastrointestinal transit. The diameter of prebiotic microcomposite scaffolds administered to MIMic were 756 pm, and there was a small swelling of the MCs in the stomach, small-intestinal and colon compartments as shown in figure 4. No prebiotic microcomposite scaffold degradation was observed throughout complete gastrointestinal transit. Furthermore, an increase in Bacteroides (average increase of 20%), Prevotella (18.9% average increases), Lachnoclostridium (3.6% average relative increase) and Enterococcus (1.4% increase), Prevotellamassila (0.7% increase) and Anaerostipes (0.4% increase) bacteria was observed. Mucosal microbiome communities exhibited similar relative increases in the abundances of the genera Bacteroides (12.7%), Prevotella (11.0%), Prevotellamassilla (4.0%), Lachnoclostridium (3.8%), Enterococcus (0.9%), Bifidobacterium (5.5%) and some other genera with minor increments, such as Ligilactobacillus (0.9%), Blautia (0.5%), Leyella (0.4%), Lactococcus (0.4%), and Agathobacter (0.3%).

[0084] This data shows that the inventive prebiotic microcomposite scaffold provides a positive impact on the microbiome in the lower gastrointestinal tract.

[0085] Additionally, changes in short chain fatty acid (i.e., butyrate, propionate, and acetate) concentrations were also examined before administration of the gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold (embodiment 1) and after administration. Three samples were tested and the results are shown in figure 5. The results revealed a significant increase in propionate concentrations across all three samples following administration of the gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold (50.5 % average increase). In contrast, acetate, and butyrate concentrations after administration of the gellan gum and carboxymethyl cellulose prebiotic microcomposite scaffold varied with increases observed in two samples, and a decrease in one sample. This is advantageous because it shows an increase in production of health-related bacterial metabolites. Without being bound by theory, it is understood that the resistance of the prebiotic microcomposite scaffold to the gastric and intestinal fluids is advantageous because it enables the microcomposite scaffold to progress through the gastric tract without being dissolved and also enables the growth of a range of bacteria, in particular mucosal-adherent bacteria, by providing a scaffold for the bacteria to interact with.

[0086] The above embodiments are described by way of example only. Many variations are possible without departing from the scope of the invention as defined in the appended claims.

Claims

CLAIMS1. A prebiotic composite scaffold comprising at least one prebiotic compound and at least one gastrointestinal-resistant biopolymer wherein the gastrointestinal- resistant biopolymer comprises at least one gellan gum or a derivative thereof.

2. A prebiotic composite scaffold according to claim 1 wherein the prebiotic compound comprises a polysaccharide.

3. A prebiotic composite scaffold according to claim 1 or claim 2 wherein the prebiotic compound comprises a cellulose or a derivative thereof.

4. A prebiotic composite scaffold according to any preceding claim wherein the prebiotic compound is carboxymethylcellulose.

5. A prebiotic composite scaffold according to any preceding claim wherein the total concentration of the gastrointestinal-resistant biopolymer(s) in the composite scaffold is between 0.1 and 5 % w / v, preferably between 1 and 3.5 % w / v.

6. A prebiotic composite scaffold according to any preceding claim wherein the gastrointestinal-resistant biopolymer comprises gellan gum and the prebiotic compound comprises carboxymethylcellulose, xanthan gum or sodium alginate.

7. A prebiotic composite scaffold according to any preceding claim wherein the w / v ratio of the or each prebiotic and the total w / v of the gastrointestinal- resistant biopolymer is between 50:1 and 1:50.

8. A prebiotic composite scaffold according to any preceding claim wherein the diameter of the composite is between 100 and 1000 pm.

9. A prebiotic composite scaffold according to any preceding claim wherein the or each prebiotic compound is encapsulated by the gastrointestinal-resistant biopolymer.

10. A prebiotic composite scaffold according to any one of claim 1 to 8 wherein the or each prebiotic compound forms a continuous or discontinuous coating on the gastrointestinal-resistant biopolymer.

11. A prebiotic composite scaffold according to any preceding claim wherein the prebiotic composite scaffold is in the form of a tablet, a capsule, a pill, a powder, a lozenge, or a potable solution.

12. A method of preparing a prebiotic composite scaffold of any of claims 1 to 11 comprising the step of prilling or ionic gelation of a solution comprising at least one gastrointestinal-resistant biopolymer and at least one prebiotic compound, wherein the gastrointestinal-resistant biopolymer comprises at least one gellan gum or a derivative thereof.

13. A method according to claim 12 wherein the prilling or ionic gelation comprises spraying the solution from a nozzle orifice comprising a diameter of between 200 pm and 1500 pm, preferably between 350 pm and 1000 pm.

14. A method according to claim 12 or 13 wherein the prilling or ionic gelation comprises spraying the solution at a flow rate of at least 1 mL / min.

15. A method according to any of claims 12 to 14 wherein the prilling or ionic gelation comprises spraying the solution at a pressure of no more than 150 mbarl .

16. A food product comprising a prebiotic composite scaffold according to any of claims 1 to 11.

17. A food supplement comprising a prebiotic composite scaffold according to any of claims 1 to 11.

18. A nutraceutical comprising a prebiotic composite scaffold according to any of claims 1 to 11.

19. A prebiotic composite scaffold according to any of claims 1 to 11 for use in promoting the growth of mucosal-associated bacteria within a colonic microbiome.

20. A prebiotic composite scaffold according to any of claims 1 to 11 for use in the treatment of a disease associated with intestinal microbiome dysbiosis.

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