BITTER BLOCKERS AND RELATED METHODS OF USE

Abstract

The present invention relates, at least in part, to compounds and compositions that can be used to mask, block, or reduce the bitter taste present in various orally consumable products. The present invention also relates to methods of using bitterness blocking compounds and compositions to mask the bitterness of various orally consumable products, hence making such orally consumable products more palatable. The present invention further relates to an orally consumable product with reduced bitterness.

Claims

1. A method of reducing or blocking the bitter taste of an orally consumable composition comprising one or more bitter tastants, the method comprising adding to the orally consumable composition an effective amount of a bitter blocker selected from the group consisting of eriodictyol-8-C-β-glucoside, homoeriodictyol 4′-O-glucoside, and homoeriodictyol 7-O-glucoside, optionally, such that the bitter taste of the orally consumable composition is reduced by at least 50%.

2. The method of claim 1, wherein the one or more bitter tastants are selected from the group consisting of caffeine, bitter methylxanthines, theobromine, rebaudioside A, a B vitamin, cannabidiol, tetrahydrocannabinol, nicotine, dextromethorphan, dextromethorphan hydrobromide, chlorhexidine, guaifenesin, pseudoephedrine, atorvastatin, aspirin, acetaminophen, diphenhydramine, doxylamine, sildenafil citrate, and loperamide.

3. The method of claim 1, wherein the orally consumable composition comprises at least 100 mg/L of the one or more bitter tastants.

4. The method of claim 1, wherein the bitter taste of the orally consumable composition is reduced by at least 50%, 60%, or 80%.

5.-8. (canceled)

9. An orally consumable composition comprising: a) one or more bitter tastants; and b) a bitter blocker selected from the group consisting of eriodictyol-8-C-β-glucoside, homoeriodictyol 4′-O-glucoside, and homoeriodictyol 7-O-glucoside; optionally, wherein the bitter blocker is present in the orally consumable composition in a concentration between about 10 ppm and about 200 ppm.

10. The composition of claim 9, wherein the one or more bitter tastants are selected from the group consisting of: caffeine, bitter methylxanthines, theobromine, rebaudioside A, a B vitamin, cannabidiol, tetrahydrocannabinol, nicotine, dextromethorphan, dextromethorphan hydrobromide, chlorhexidine, guaifenesin, pseudoephedrine, atorvastatin, aspirin, acetaminophen, diphenhydramine, doxylamine, sildenafil citrate, and loperamide.

11. The composition of claim or claim 9, comprising at least 100 mg/L of the one or more bitter tastants.

12. The composition of claim 9, wherein the composition is selected from the group consisting of a food product, a functional food, a pharmaceutical, a dietary supplement, a dental hygiene composition, a food grade gel composition, a cosmetic product, and a flavoring product.

13. The composition of claim 9, wherein the composition is a beverage product selected from the group consisting of coffee, tea, fermented tea, a dairy beverage, a plant-based milk beverage, an alcoholic beverage, flavored water, vitamin water, fruit juice, and an energy drink.

14.-16. (canceled)

17. The method or use of claim 1, wherein the one or more bitter tastants are in a orally consumable composition.

18. (canceled)

19. A method of preparing a flavonoid glycoside, the method comprising incubating a reaction mixture comprising: (i) a) uridine diphosphate-glucose, b) eriodictyol as a substrate, and c) a glycosyltransferase comprising an amino acid sequence having at least 80% sequence identity to SEQ ID NO: 1, wherein a glucose is covalently coupled to the eriodictyol substrate to produce eriodictyol-8-C-β-glucoside, optionally wherein the glycosyltransferase comprises the amino acid sequence of SEQ ID NO: 1, or (ii) a) uridine diphosphate-glucose, b) homoeriodictyol as a substrate, and c) a glycosyltransferase comprising an amino acid sequence having at least 80% sequence identity to SEQ ID NO: 3 or SEQ ID NO: 5, wherein a glucose is covalently coupled to the homoeriodictyol substrate to produce homoeriodictyol 4′-O-glucoside and/or homoeriodictyol 7-O-glucoside, optionally wherein the glycosyltransferase comprises the amino acid sequence of SEQ ID NO: 3 or SEQ ID NO: 5.

20. (canceled)

21. The method of claim 19, wherein the reaction mixture is in vitro.

22. The method of claim 19, wherein the reaction mixture is a cell-based reaction mixture.

23. The method of claim 22, wherein the cell-based reaction mixture comprises a cell comprising a polynucleotide encoding the glycosyltransferase, wherein the polynucleotide comprises a nucleotide sequence that is at least 90% identical to any one of SEQ ID NOs: 2, 4, 6.

24.-29. (canceled)

30. A reaction mixture comprising: (a) uridine diphosphate-glucose, (b) a natural flavanone, and (c) a host cell comprising a glycosyltransferase comprising an amino acid sequence having at least 80% sequence identity to any one of SEQ ID NOs: 1, 3, 5.

31. The reaction mixture of claim 30, wherein the natural flavanone is homoeriodictyol, eriodictyol, or combinations thereof.

32. The reaction mixture of claim 30, wherein the host cell is a bacterial cell.

33. The reaction mixture of claim 30, wherein the host cell is an Escherichia coli (E. coli) cell.

34. (canceled)

35. The reaction mixture of claim 30, further comprising: eriodictyol-8-C-β-glucoside, homoeriodictyol 4′-O-glucoside, homoeriodictyol 7-O-glucoside, or combinations thereof.

36. A compound produced by the method of claim 19.

37.-38. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The following drawings form part of the present specification and are included to further demonstrate certain aspects of the present disclosure, which may be better understood by reference to one or more of these drawings in combination with the detailed description of specific embodiments presented in this disclosure. The accompanying drawings are not intended to be drawn to scale. The drawings are illustrative only and are not required for enablement of the disclosure. For purposes of clarity, not every component may be labeled in every drawing. In the drawings:

[0038] FIG. 1 shows the results of ID and 2D NMR analyses of bitter blocker candidate 09 (BB09).

[0039] FIG. 2 shows the chemical structure of BB09.

[0040] FIG. 3 shows the results of HPLC analysis of BB09 standard (top panel) and purified BB09 (bottom panel).

[0041] FIG. 4 shows the results of 1D and 2D NMR analyses of bitter blocker candidate 11 (BB11).

[0042] FIG. 5 shows the chemical structure of BB11.

[0043] FIG. 6 shows the results of HPLC analysis of BB 11 standard (top panel) and purified BB11 (bottom panel).

[0044] FIG. 7 shows the results of H-NMR analysis of bitter blocker candidate 13 (BB13) in deuterated dimethyl sulfoxide (DMSO-d6).

[0045] FIG. 8 shows the results of H-NMR analysis of BB13 in DMSO with d6-D.sub.2O-exchange.

[0046] FIG. 9 shows the chemical structure of BB13.

[0047] FIG. 10 shows the results of HPLC analysis of BB13 standard (top panel) and purified BB13 (bottom panel).

[0048] FIG. 11 shows the results of a two-alternative forced choice (2AFC) difference test completed by fifteen panelists, Each panelist provided two separate evaluations, resulting in a total of thirty evaluations. Results are statistically significant at the 90% and 95% confidence interval.

[0049] FIG. 12 shows a concentration-responsive curve of Compound A (BB09), Compound B (BB11), and Compound C (BB13) with 100 μM Dextromethorphan-HBr as the Bitter Stimulus. Response was measured by luminescence, *p<0.05 by one-way ANOVA.

[0050] FIG. 13 shows a concentration-responsive curve of Compound A (BB09), Compound B (BB11), Compound C (BB13), Senomyx BB68, and STX001 with 400 μM L-Praziquantel in pooled donor-derived human taste bud tissue-derived cells (hTBEC). Response was measured by luminescence. *p<0.05 by one-way ANOVA.

[0051] FIGS. 14A-14B show normalized concentration-responsive curves of Compound A (BB09), Compound B (BB11), Compound C (BB13), STX001, Sodium Gluconate, Eridyctiol, Homoeridictyol, and Semonyx B868 with either 100 μM Dextromethorphan-HBr stimulus in individual donor-derived hTBECs (FIG. 14A) or 400 μM L-Praziquantel stimulus in individual donor-derived hTBECs (FIG. 14B). Response was measured by luminescence. *p<0.05 by one-way ANOVA.

[0052] FIG. 15 shows real time ATP secretion in hTBEC 66 in response to 300 μM Theobromine alone (Vehicle), 300 μM Theobromine with 1000 μM of Senomyx BB68, or 300 μM Theobromine with 1000 μM of Compound C (BB13).

[0053] FIG. 16 shows ATP secretion signal in pooled hTBEC 56 cultures in response to a DMSO control, 3mM Rebaudioside A with Compound A (BB09), 3 mM Rebaudioside A with Compound B (BB11), 3 mM Rebaudioside A with Compound C (BB13), 3 mM Rebaudioside A with Senomyx BB68, 3 mM Rebaudioside A with ST X001, 3 mM Rebaudioside A with Homoeridictyol, 3 mM Rebaudioside A with Eridictyol, and 3 mM Rebaudioside A with Sodium Gluconate. Each antagonist treated with 3 mM Rebaudioside A is provided as DMSO control, 100 μM, 300 μM, or 1,000 μM. *p<0.05 by one-way ANOVA.

[0054] FIG. 17 shows real time ATP secretion in pooled hTBEC 56 cultures in response to 1 mM Rebaudioside A alone (Vehicle), 1 mM Rebaudioside A with 1,000 μM Compound A (BB09), 1 mM Rebaudioside A with 1,000 μM Compound C (BB13), and 1 mM Rebaudioside A with 1,000 μM Senomyx BB68.

[0055] FIGS. 18A-18C show real time ATP secretion detection profiling of three hTBEC donor cultures: hTBEC 66 (FIG. 18A), hTBEC 56 (FIG. 18B), and hTBEC Donor H (FIG. 18C). Each donor culture was treated with 100 μM Dextromethorphan-HBr alone (Vehicle), 100 μM Dextromethorphan-HBr with 100 μM Compound A (BB09), 100 μM Dextromethorphan-HBr with 100 μM Compound B (BB11), 1.00 μM Dextromethorphan-HBr with 100μM Compound C (BB13), 100 μM Dextromethorphan-HBr with 100 μM STX001, or 100 μM Dextromethorphan-HBr with 100 μM Senomyx BB68. *p<0.05 by one-way ANOVA.

[0056] FIGS. 19A-19C show real time ATP secretion detection profiling of three hTBEC donor cultures: hTBEC 66 (FIG. 19A), hTBEC 56 (FIG. 19B), and hTBEC Donor H (FIG. 19C). Each donor culture was treated with 1,000 μM Theobromine alone (Vehicle), 1,000 μM Theobromine with 1,000 μM Compound A (BB09), 1,000 μM Theobromine with 1,000 μM Compound B (BB11), 1,000 μM Theobromine with 1,000 μM Compound C (BB13), 1,000 μM Theobromine with 1,000 μM STX001, or 1,000 μM Theobromine with 1,000 μM Senomyx BB68. *p<0.05 by one-way ANOVA.

[0057] FIGS. 20A-20C show real time ATP secretion detection profiling of three hTBEC donor cultures: hTBEC 66 (FIG. 20A), hTBEC 56 (FIG. 20B), and hTBEC Donor H (FIG. 20C). Each donor culture was treated with 1 mM Rebaudioside A alone (Vehicle), 1 mM Rebaudioside A with 1 mM Compound A (BB09), 1 mM Rebaudioside A with 1 mM Compound B (BB11), 1 mM Rebaudioside A with 1 mM Compound C (BB13), 1 mM Rebaudioside A with 1 mM STX001, or 1 mM Rebaudioside A with 1 mM Senomyx BB68. *p<0.05 by one-way ANOVA.

[0058] FIGS. 21A-21C show real time ATP secretion detection profiling of three hTBEC donor cultures: hTBEC 66 (FIG. 21A), hTBEC 56 (FIG. 21B), and hTBEC Donor H (FIG. 21C). Each donor culture was treated with 3 mM Caffeine alone (Vehicle), 3 mM Caffeine with 3 mM Compound A (BB09), 3 mM Caffeine with 3 mM Compound B (BB11), 3 mM Caffeine with 3 mM Compound C (BB13), 3 mM Caffeine with 3 mM STX001, or 3 mM Caffeine with 3 mM Senomyx BB68. *p<0.05 by one-way ANOVA.

[0059] FIGS. 22A-22B show ATP secretion detection profiling of three hTBEC donor cultures: hTBEC 66, hTBEC 56, and hTBEC Donor H. FIG. 22A shows the response of each donor culture to either 100 μM Dextromethorphan-HBr alone (Vehicle) or 100 μM Dextromethorphan-HBr with 1 mM Compound C (BB13). FIG. 22B shows the response of each donor culture to either 1,000 μM Theobromine alone (Vehicle) or 1,000 μM Theobromine with 1 mM Compound C (BB13). *p<0.05 by one-way ANOVA.

[0060] FIGS. 23A-23B show ATP secretion detection profiling of three hTBEC donor cultures: hTBEC 66, hTBEC 56, and hTBEC Donor H. FIG. 23A shows the response of each donor culture to either 1 mM Rebaudioside A alone (Vehicle) or 1 mM Rebaudioside A with 1 mM Compound C (BB13). FIG. 23B shows the response of each donor culture to either 3 ,M Caffeine alone (Vehicle) or 3 mM Caffeine with 1 mM Compound C (BB13). *p<0.05 by one-way ANOVA.

[0061] FIG. 24 shows ATP secretion detection profiling of three hTBEC donor cultures: hTBEC 15 66, hTBEC 56, and hTBEC Donor H. Each culture was treated with either 400 mM L-Praziquantel alone (Vehicle) or 400 mM L-Praziquantel with 1 mM Compound C (BB13). *p<0.05 by one-way ANOVA.

[0062] FIG. 25 shows a cell calcium mobilization assay from individual donor-derived hTBECs in response to treatment with 100 μM Dextromethorphan-HBr and Compound C (BB13) at a concentration from 0.3 μM to 1,000 μM.

[0063] FIG. 26 shows a cell calcium mobilization assay from individual donor-derived hTBECs in response to treatment with 300 μM Theobromine and Compound C (BB13) at a concentration from 1 μM to 3,000 μM.

[0064] FIG. 2 shows a cell calcium mobilization assay from hTBEC 56 cells in response to treatment with 3 mM Caffeine alone (Vehicle), 3 mM Caffeine with 1,000 μL Senomyx BB68, or 3 mM Caffeine with 1,000 μM Compound C (BB13).

DETAILED DESCRIPTION

[0065] Bitter-tasting substances or bitter tastants within the meaning of the present disclosure can be, for example, xanthine alkaloids (e.g., caffeine, theobromine), bitter methylxanthines pyridine alkaloids (e.g., nicotine), quinoline derivatives (e.g., quinine), limonoids limonine from citrus fruits), polyphenols catechols, flavonols, gamma-oryzanol, hesperitin), pharmaceutically active compounds (e.g., fluoroquinoline antibiotics, aspirin, beta-lactam antibiotics, ambroxol, paracetamol, aspirin, guaifenesin), dextromethorphan, dextromethorphan hydrobromide, rebaudioside A, denatonium benzoate, sucralose octaacetate, potassium chloride, magnesium salts, urea, bitter amino acids (e.g., tryptophan), and bitter peptide fragments (e.g., having a terminal leucine or isoleucine radical). As shown in the examples below, bitter blockers according to the present invention are extremely effective in reducing or blocking the bitter taste originated from various bitter tastants.

[0066] The present bitter blockers also can be effective in reducing or blocking a bitter off-taste or aftertaste. Substances which have a bitter aftertaste within the meaning of the present disclosure can be, for example, an artificial or a natural sweetener with a bitter aftertaste selected from the group consisting of abiziasaponin, abrusosides (e.g., abrusoside A, abrusoside B, abrusoside C, abrusoside D), acesulfame potassium, advantame, albiziasaponin, alitame, aspartame, superaspartame, bayunosides (e.g., bayunoside 1, bayunoside 2) brazzein, bryoside, bryonoside, bryonodulcoside, carnosifloside, carrelame, curculin, cyanin, chlorogenic acid, cyclamates and its salts, cyclocarvoside I, dihydroquercetin-3-acetate, dihydroflavenol, dulcoside, gaudichaudioside, glycyrrhizin, glycyrrhetin acid, gypenoside, hematoxylin, hernandulcin, isomogrosides (e.g., iso-mogroside V), lugduname, magap, mabinlins, micraculin, mogrosides (e.g., mogroside IV and mogroside V), monatin and its derivatives, monellin, mukurozioside, naringin dihydrochalcone (NarDHC), neohesperidin dihydrochalcone (NDHC), neotame, osladin, pentadin, periandrin I-V, perillartine, D-phenylalanine, phlomsosides, in particular phlomisoside 1, phlomisoside 2, phlomisoside 3, phlomisoside 4, phloridzin, phyllodulcin, polpodiosides, polypodoside A, pterocaryosides, rebaudiosides (e.g., rebaudioside A, rebaudioside B, rebaudioside C, rebaudioside D, rebaudioside F, rebaudioside G, rebaudioside H), rubusosides, saccharin and its salts and derivatives, scandenoside, selligueanin A, siamenosides (e.g., siamenoside I), strogines (e.g., strogin 1, strogin 2, strogin 4), suavioside A, suavioside B, suavioside G, suavioside H, suavioside I, suavioside J, sucralose, sucronate, sucrooctate, talin, telosmoside A15, thaumatin (e.g., thaumatin I and II), trans-anethol, trans-cinnamaldehyde, trilobatin, and D-tryptophane, including extracts or enriched fractions of the natural sweeteners.

[0067] In some embodiments, the present bitter blockers, i.e., eriodictyol-8-C-β-glucoside, homoeriodictyol 4′-O-glucoside, and/or homoeriodictyol 7-O-glucoside, are selected for their ability to reduce the bitterness of certain bitter tastants, and yet not completely block the desired bitter notes typical of, for example, coffee and chocolate, or their aroma.

[0068] In various embodiments, the present invention relates to methods of using eriodictyol-8-C-β-glucoside, homoeriodictyol 4′-O-glucoside, and/or homoeriodictyol 7-O-glucoside as hitter blockers. The method generally includes adding to a consumable composition comprising a bitter tastant an amount of at least one of the present bitter blockers that is effective to modify, mask, reduce and/or suppress the hitter taste of the bitter tastant, wherein the amount of the bitter blocker can be less than a taste threshold concentration associated with the bitter blocker, and wherein the effect of the bitter blocker remains at least as long as the taste of the bitter tastant is perceived. In the context of the present invention, the term “threshold” concentration means that the hitter blocker is present in an amount at which it is either not recognizable and/or identifiable and/or does not exert an undesired taste effect, but still exerts its respective bitter blocking effects.

[0069] In some embodiments, the consumable composition can include a sweetener that provides a complimentary masking effect to the bitter-blocking effect of the bitter blocker. In other embodiments, the consumable composition can exclude sweeteners.

[0070] In certain embodiments, the consumable composition can include a flavor agent. The flavor agent can be chosen from synthetic flavor oils and flavoring aromatics, and/or oils, oleo resins and extracts derived from plants, leaves, flowers, fruits and so forth, and combinations thereof. Representative flavor oils include cinnamon oil, peppermint oil, clove oil, bay oil, eucalyptus oil, thyme oil, cedar leaf oil, oil of nutmeg, oil of sage, and oil of bitter almonds. Also useful are artificial, natural or synthetic fruit flavors such as vanilla, and citrus oil, including lemon, orange, grape, lime and grapefruit and fruit essences including apple, pear, peach, strawberry, raspberry, cherry, plum, pineapple, apricot and so forth. Any of these flavor agents may be used individually or in admixture. Commonly used flavors include mints such as peppermint, menthol, vanilla, cinnamon derivatives, and various fruit flavors, whether employed individually or in admixture. Flavor agents such as aldehydes and esters including cinnamyl acetate, cinnamaldehyde, citral, diethyllacetal, dihydrocarvyl acetate, eugenyl formate, p-methylanisole, and so forth may also be used. Generally, any flavoring or food additive such as those described in Chemicals Used in Food Processing, pub 1274 by the National Academy of Sciences, pages 63-258 may be used as flavor agents in the invention.

[0071] In general, the consumable compositions of the present invention can be prepared utilizing techniques well known to those of ordinary skill in the art. As such, the consumable compositions of the present invention may include various other components which are customarily used in the preparation of such consumable compositions, and which would be known to those of skill in the art.

[0072] The present consumable composition can be formulated into various forms including tablets, chews, edible films, gels, solutions, suspensions, emulsions, and so forth. For example, when the consumable composition of the present invention is in the form of a liquid pharmaceutical composition, or even a toothpaste, dental cream, or gel, such a form typically includes a liquid carrier material for the bitter tastant and the bitter blocker. The carrier material may comprise water, typically in an amount of from about 10% to about 90% by weight of the consumable composition. Carrier materials include, but are not limited to, polyethylene glycol (PEG), propylene glycol (PG), glycerin or mixtures thereof. In addition, the consumable composition may include humectants, such as, for example, sorbitol, glycerin, and polyalcohols. Particularly advantageous liquid ingredients comprise mixtures of water with polyethylene glycol, propylene glycol, or glycerin and sorbitol. A gelling agent (thickening agent) including natural or synthetic gums, such as sodium carboxymethylcellulose, hydroxyethyl cellulose, methyl cellulose and the like, may also be used, typically in the range of about 0.15% to about 1.30% by weight of the consumable composition. In a toothpaste, dental cream or gel, the liquids and solids are proportioned to form a creamy or gelled mass which is extrudable from a pressurized container or from a collapsible tube.

[0073] The consumable composition of the present invention may also include a thickening agent or binder. For example, the thickening agent or binder may be selected from the group consisting of finely particulate gel silicas and nonionic hydrocolloids, such as carboxymethyl cellulose, sodium hydroxymethyl cellulose, hydroxyethylcellulose, hydroxypropyl guar, hydroxyethyl starch, polyvinyl pyrrolidone, vegetable gums, such as tragacanth, agar, carrageenans, gum arabic, xanthan gum, guar gum, locust bean gum, carboxyvinyl polymers, fumed silica, silica clays and the like, and combinations thereof. For example, a preferred thickening agent for use in toothpastes is carrageenan available under the trade names GELCARIN® and VISCARIN® from FMC Biopolymers, Philadelphia, Pa., U.S.A. Other thickening agents or binders are polyvinyl pyrrolidone available from Noveon, Inc. Cleveland, Ohio, U.S.A. wider the trademark CARBOPOL®, fumed silica under the trademark CAB-O-SIL® available from Cabot Corporation, Boston, Mass., U.S.A., and silica clays available from Laporte industries, Ltd., London, U.K. under the trademark LAPOINTE®, The thickening agent or binder may be used with or without a carrier; such as glycerol, polyethylene glycol (e.g., PEG-400), or combinations thereof; however, when a carrier is used; preferably up to about 5% thickening agent or hinder, more preferably from about 0.1% to about 1.0%, is combined with preferably from about 95.0% to about 99.9% carrier, more preferably from about 99.0% to about 99.9%, based on the total weight of the thickening agent/carrier combination. Furthermore, when the thickening agent or binder is a hydrated silica and it is used with a carrier, preferably from about 5% to about 10% thickening agent or binder is combined with preferably from about 90% to about 95% carrier, based on the total weight of the thickening agent/carrier combination.

[0074] The consumable composition of the present invention may also contain coloring agents or colorants, such as colors, dyes, pigments, and particulate substances, in amounts effective to produce the desired color of the particular consumable composition. The coloring agents (colorants) useful in the invention include the pigments such as titanium dioxide, which may be incorporated in amounts of up to about 2% by weight of the consumable composition, and preferably less than about 1% by weight. Colorants may also include natural food colors and dyes suitable for food, drug and cosmetic applications. For example, food grade and/or pharmaceutically acceptable coloring agents, dyes, or colorants, as would be understood to one 20 skilled in the art, include FD&C colorants such as primary FD&C Blue No. 1, FD&C Blue No. 2, FD&C Green No. 3, FD&C Yellow No. 5, FD&C Yellow No. 6, FD&C Red No. 3, FD&C Red No. 33 and FD&C Red No. 40 and lakes FD&C Blue No. 1; FD&C Blue No. 2, FD&C Yellow No. 5, FD&C Yellow No. 6, FD&C Red No. 2, FD&C Red No. 3, FD&C Red No. 33, FD&C Red No. 40 and combinations thereof.

[0075] In addition, the consumable composition of the invention may also include a surfactant, such as sodium lauryl sulfate (SLS) (preferably in an amount of from about 1% to about 2% of the total weight of the oral composition), and/or a preservative, such as sodium benzoate (preferably in an amount of about 0.2% of the total weight of the oral composition).

[0076] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the disclosure belongs. Although any methods and materials similar to or equivalent to those described herein can be used in the practice or testing of the present disclosure, the preferred materials and methods are described below.

[0077] The disclosure will be more fully understood upon consideration of the following non-limiting Examples. It should be understood that these examples, while indicating preferred embodiments of the subject technology, are given by way of illustration only. From the above discussion and these examples, one skilled in the art can ascertain the essential characteristics of the subject technology, and without departing from the spirit and scope thereof, can make various changes and modifications of the subject technology to adapt it to various uses and conditions.

EXAMPLES

Bitter Blocker Candidates

[0078] Table 1 below provides the chemical name, formula, molar mass, and chemical structure of various bitter blocker candidates.

TABLE-US-00001 TABLE 1 Sample Molar Name Chemical Name Formula Mass Chemical Structure BB01 Acacetin C.sub.16H.sub.12O.sub.5 284.26 g/mol [00001] BB02 Homoeriodictyol C.sub.16H.sub.14O.sub.6 302.2788 g/mol [00002] BB03 Kaempferol C.sub.15H.sub.10O.sub.6 286.23 g/mol [00003] BB04 Dihydroquercetin C.sub.15H.sub.12O.sub.7 304.25 g/mol [00004] BB05 Dihydroquercetin glucoside C.sub.21H.sub.20O.sub.12 466.0955 g/mol [00005] BB06 Dihydrokaempferol C.sub.15H.sub.12O.sub.6 288.25 g/mol [00006] BB07 Eriodictyol C.sub.15H.sub.12O.sub.6 288.25 g/mol [00007] BB08 Dibydromyricetin C.sub.15H.sub.12O.sub.8 320.25 g/mol [00008] BB09 Homoeriodictyol 7- O-glucoside C.sub.22H.sub.24O.sub.11 464.4 g/mol [00009] BB10 Eriodictyol 7-O- glucoside C.sub.21H.sub.22O.sub.11 450.39 g/mol [00010] BB11 Homoeriodictyol 4′-O-glucoside C.sub.22H.sub.24O.sub.11 464.4 g/mol [00011] BB12 Eriodictyol 4′-O- glucoside C.sub.21H.sub.22O.sub.11 450.39 g/mol [00012] BB13 Eriodictyol-8-C-β- glucoside C.sub.21H.sub.22O.sub.11 450.39 g/mol [00013]

Example 1—Reducing the Bitterness of a Caffeine Solution

[0079] The bitter blocker candidates listed in Table 1 were prepared into a 1% sample solution with propylene glycol (i.e., 1 g of bitter blocker per 100 ml of propylene glycol) and heated to ensure complete solubilization. Each of the sample solutions were observed to give a slightly yellow color appearance. Individually, the respective sample solution was added to a 0.25% caffeine solution (i.e., a concentration of 0.25 g caffeine in 100 ml of water), which by itself tasted bitter on all areas of the tongue. A trained sensory evaluator was asked to estimate the perceived bitterness reduction against the control, as well as to provide comments on how the addition of the individual sample solution modulated the taste and mouth feel profile of the resulting caffeine solution. The results are summarized in Table 2 below.

TABLE-US-00002 TABLE 2 Estimated % Sample Dosage bitterness Name (ppm) reduction Comments BB01 20 20% Some bitterness blocking on sides and tip of tongue BB02 20 30% Some blocking on sides and tip of tongue BB03 20 20% Some bitterness blocking on sides and tip of tongue BB04 30 40% Some bitterness blocking on sides and tip of tongue BB05 30 20% Some bitterness blocking on the back of the tongue, minimal reduction BB06 50 40% Some bitterness blocking on sides and back of tongue BB07 50 50% Some bitterness blocking on all parts of the tongue, good reduction BB08 50 20% Some bitterness blocking on front of the tongue, minimal reduction BB09 50-100 60-80% .sup.   Good upfront bitterness reduction with significant bitterness reduction BB10 50-100 30% Some bitterness blocking on front of the tongue, minimal reduction BB11 50-100 60-80% .sup.   Blocks all parts of the tongue with significant bitterness reduction BB12 50-100 30% Some bitterness blocking on front and sides of the tongue, minimal reduction BB13 50-100 80-100%     Blocks all parts of the tongue with almost total bitterness blocking

Example 2—Reducing the Bitterness of a Peach-Flavored Energy Drink

[0080] The bitterness blocker candidates listed in Table 1 were prepared into a 1% sample solution with propylene glycol and heated to ensure complete solubilization. Each of the sample solutions were observed to give a slightly yellow color appearance. Individually, the respective sample solution was added to a commercially available peach-flavored energy drink which has a bitter taste due to the presence of caffeine (168 mg/8 fl oz serving or about 710 mg/l) and the recommended daily allowances of various B vitamins. A trained sensory evaluator was asked to estimate the perceived bitterness reduction against the control, as well as to provide comments on how the addition of the individual sample solution modulated the taste and mouth feel profile of the resulting peach-flavored energy drink. The results are summarized in Table 3 below.

TABLE-US-00003 TABLE 3 Estimated % Sample Dosage bitterness Name (ppm) reduction Comments BB01 20 20% Some bitterness blocking on sides and tip of tongue BB02 20 30% Some blocking on sides and tip of tongue BB03 20 20% Some bitterness blocking on sides and tip of tongue BB04 20 40% Some bitterness blocking on sides and tip of tongue BB05 20 20% Some bitterness blocking on the back of the tongue BB06 50 40% Some bitterness blocking on sides and back of tongue BB07 50 50% Some bitterness blocking on all parts of the tongue BB08 50 20% Some bitterness blocking on front of the tongue BB09 50-100 60-80% .sup.   Good upfront bitterness reduction BB10 50-100 30% Some bitterness blocking on front of the tongue BB11 50-100 80% Good bitterness reduction with just a slight bitterness in the end BB12 50-100 30% Some bitterness blocking on front and sides of the tongue BB13 50-100 80-100%     Excellent bitter blocking throughout

Example 3—Reducing the Bitterness of Dark Chocolate Pieces

[0081] The bitterness blocker candidates listed in Table 1 were prepared into a 1% sample solution with propylene glycol and heated to ensure complete solubilization. Each of the sample solutions were observed to give a slightly yellow color appearance. Individually, the respective sample solution was added to melted dark chocolate pieces with 100% dark cacao. A trained sensory evaluator was asked to estimate the perceived bitterness reduction against the control, as well as to provide comments on how the addition of the individual sample solution modulated the taste and mouth feel profile of the resulting melted dark chocolate pieces. The results are summarized in Table 4 below.

TABLE-US-00004 TABLE 4 Estimated % Sample Dosage bitterness Name (ppm) reduction Comments BB01 50 20% Some bitterness blocking on sides and tip of tongue BB02 50 20% Some blocking on sides and tip of tongue BB03 50 20% Some bitterness blocking on sides and tip of tongue BB04 50 40% Some bitterness blocking on sides and tip of tongue BB05 50 20% Some bitterness blocking on the back of the tongue BB06 50 40% Some bitterness blocking on sides and back of tongue BB07 50 50% Some bitterness blocking on all parts of the tongue BB08 50 20% Some bitterness blocking on front of the tongue BB09 100 40-60% .sup.   Good bitterness reduction but bitterness still there BB10 100 30% Some bitterness blocking on front of the tongue BB11 100 60% Good bitterness reduction but bitterness still there BB12 100 30% Some bitterness blocking on front and sides of the tongue BB13 100 80-100%     Complete bitter blocking with good upfront finish

Example 4—Reducing the Bitterness of Dark Roast Coffee

[0082] The bitterness blocker candidates listed in Table 1 were prepared into a 1% sample solution with propylene glycol and heated to ensure complete solubilization. Each of the sample solutions were observed to give a slightly yellow color appearance. Individually, the respective sample solution was added to dark roast coffee (which is estimated to contain about 175 mg of caffeine per 8 fl oz, or about 740 mg/l)). A trained sensory evaluator was asked to estimate the perceived bitterness reduction against the control, as well as to provide comments on how the addition of the individual sample solution modulated the taste and mouth feel profile of the resulting dark roast coffee. The results are summarized in Table 5 below.

TABLE-US-00005 TABLE 5 Estimated % Sample Dosage bitterness Name (ppm) reduction Comments BB01 50 20% Some bitterness blocking on sides and tip of tongue BB02 50 20% Some blocking on sides and tip of tongue BB03 50 20% Some bitterness blocking on sides and tip of tongue BB04 50 40% Some bitterness blocking on sides and tip of tongue BB05 50 20% Some bitterness blocking on the back of the tongue BB06 50 40% Some bitterness blocking on sides and back of tongue BB07 50 50% Some bitterness blocking on all parts of the tongue BB08 50 20% Some bitterness blocking on front of the tongue BB09 50 60-80% .sup.   Nice upfront bitterness reduction with some bitter finish in the end BB10 100 30% Some bitterness blocking on front of the tongue BB11 100 80% Nice upfront bitterness reduction with some bitter finish in the end BB12 100 30% Some bitterness blocking on front and sides of the tongue BB13 100 80-100%     Very smooth with nice upfront bitter blocking as well as nice finish in the end.

Example 5—Reducing the Bitterness of Cough Syrup

[0083] The bitterness blocker candidates listed in Table 1 were prepared into a 1% sample solution with propylene glycol and heated to ensure complete solubilization. Each of the sample solutions were observed to give a slightly yellow color appearance. Individually, the respective sample solution was added to a cough syrup sold under the trade name DELSYM®. The bitter-tasting agent contained in the cough syrup were dextromethorphan HBr USP 30 mg (as measured for each 5 ml teaspoon, i.e., 6000 mg/l of dextromethorphan). A trained sensory evaluator was asked to estimate the perceived bitterness reduction against the control, as well as to provide comments on how the addition of the individual sample solution modulated the taste and mouth feel profile of the resulting cough syrup. The results are summarized in Table 6 below.

TABLE-US-00006 TABLE 6 Estimated % Sample Dosage bitterness Name (ppm) reduction Comments BB01 50 20% Some bitterness blocking on sides and tip of tongue BB02 50 20% Some blocking on sides and tip of tongue BB03 50 20% Some bitterness blocking on sides and tip of tongue BB04 50 20% Some bitterness blocking on sides and tip of tongue BB05 50 20% Some bitterness blocking on the back of the tongue BB06 50 40% Some bitterness blocking on sides and back of tongue BB07 50 30% Some bitterness blocking on all parts of the tongue BB08 50 20% Some bitterness blocking on front of the tongue BB09 100 50% Covered up a good percentage of bitterness. BB10 100 30% Some bitterness blocking on front of the tongue BB11 100 60% Less bitter, smoother, more palatable, sweeter in taste. BB12 100 30% Some bitterness blocking on front and sides of the tongue BB13 100 80% Almost blocked all the bitterness, sweeter, more palatable, thicker in mouth feel.

[0084] Example 6—Reducing the Bitterness of Cough Syrup

[0085] The bitterness blocker candidates listed in Table 1 were prepared into a 1% sample solution with propylene glycol and heated to ensure complete solubilization. Each of the sample solutions were observed to give a slightly yellow color appearance. Individually, the respective sample solution was added to a cough syrup sold under the trade name ROBITUSSIN® DM. The bitter-tasting agents contained in the cough syrup were dextromethorphan HBr USP 20 mg and guaifenesin USP 400 mg (as measured for each 20 ml serving, or 21000 mg/l of bitter tastants in total). A trained sensory evaluator was asked to estimate the perceived bitterness reduction against the control, as well as to provide comments on how the addition of the individual sample solution modulated the taste and mouth feel profile of the resulting cough syrup. The results are summarized in Table 7 below.

TABLE-US-00007 TABLE 7 Estimated % Sample Dosage bitterness Name (ppm) reduction Comments BB01 50 20% Some bitterness blocking on sides and tip of tongue BB02 50 20% Some blocking on sides and tip of tongue BB03 50 20% Some bitterness blocking on sides and tip of tongue BB04 50 20% Some bitterness blocking on sides and tip of tongue BB05 50 20% Some bitterness blocking on the back of the tongue BB06 50 40% Some bitterness blocking on sides and back of tongue BB07 50 30% Some bitterness blocking on all parts of the tongue BB08 50 20% Some bitterness blocking on front of the tongue BB09 100 50% Covered up a good percentage of bitterness. BB10 100 30% Some bitterness blocking on front of the tongue BB11 100 60% Less bitter, smoother, more palatable, sweeter in taste. BB12 100 30% Some bitterness blocking on front and sides of the tongue BB13 100 80% Almost blocked all the bitterness, sweeter, more palatable.

Example 7—Reducing the Bitterness of Full Spectrum CBD Hemp Oil

[0086] The bitterness blocker candidates listed in Table 1 were prepared into a 1% sample solution with propylene glycol and heated to ensure complete solubilization. Each of the sample solutions were observed to give a slightly yellow color appearance. A full spectrum CBD hemp oil was emulsified into a water-soluble nanoemulsion first, to which was added the respective sample solution. The full spectrum CBD hemp oil by itself has an earthy, musky, bitter taste. A trained sensory evaluator was asked to estimate the perceived bitterness reduction against the control, as well as to provide comments on how the addition of the individual sample solution modulated the taste and mouth feel profile of the resulting oil nanoemulsion. The results are summarized in Table 8 below.

TABLE-US-00008 TABLE 8 Estimated % Sample Dosage bitterness Name (ppm) reduction Comments BB01 50 30% Some bitterness blocking on sides and tip of tongue BB02 50 30% Some blocking on sides and tip of tongue BB03 50 30% Some bitterness blocking on sides and tip of tongue BB04 50 30% Some bitterness blocking on sides and tip of tongue BB05 50 30% Some bitterness blocking on the back of the tongue BB06 50 40% Some bitterness blocking on sides and back of tongue BB07 50 30% Some bitterness blocking on all parts of the tongue BB08 50 30% Some bitterness blocking on front of the tongue BB09 100 60% Nice upfront bitterness reduction with some bitter finish in the end BB10 100 30% Some bitterness blocking on front of the tongue BB11 100 60% Nice upfront bitterness reduction with slight bitterness in the end BB12 100 30% Some bitterness blocking on front and sides of the tongue BB13 100 80% Almost blocked all the bitterness, very smooth finish.

Example 8—Reducing the Bitterness of CBD Isolate

[0087] The bitterness blocker candidates listed in Table 1 were prepared into a 1% sample solution with propylene glycol and heated to ensure complete solubilization. Each of the sample solutions were observed to give a slightly yellow color appearance. A CBD isolate was emulsified into a water-soluble nanoemulsion first, to which was added the respective sample solution. The CBD isolate by itself was noted to have an earthy flavor. A trained sensory evaluator was asked to estimate the perceived bitterness reduction against the control, as well as to provide comments on how the addition of the individual sample solution modulated the taste and mouth feel profile of the resulting nanoemulsion. The results are summarized in Table 9 below.

TABLE-US-00009 TABLE 9 Estimated % Sample Dosage bitterness Name (ppm) reduction Comments BB01 50 30% Some bitterness blocking on sides and tip of tongue BB02 50 30% Some blocking on sides and tip of tongue BB03 50 30% Some bitterness blocking on sides and tip of tongue BB04 50 30% Some bitterness blocking on sides and tip of tongue BB05 50 30% Some bitterness blocking on the back of the tongue BB06 50 40% Some bitterness blocking on sides and back of tongue BB07 50 30% Some bitterness blocking on all parts of the tongue BB08 50 30% Some bitterness blocking on front of the tongue BB09 100 60% Nice upfront bitterness reduction with some bitter finish in the end BB10 100 30% Some bitterness blocking on front of the tongue BB11 100 60% Nice upfront bitterness reduction with slight bitterness in the end BB12 100 30% Some bitterness blocking on front and sides of the tongue BB13 100 80% Almost blocked all the bitterness, very smooth finish.

Example 9—Reducing the Bitterness of THC

[0088] The bitterness blocker candidates listed in Table 1 were prepared into a 1% sample solution with propylene glycol and heated to ensure complete solubilization. Each of the sample solutions were observed to give a slightly yellow color appearance. THC was first emulsified into a water-soluble nanoemulsion (10 mg THC per serving), to which was added the respective sample solution. A trained sensory evaluator was asked to estimate the perceived bitterness reduction against the control, as well as to provide comments on how the addition of the individual sample solution modulated the taste and mouth feel profile of the resulting nanoemulsion. The results are summarized in Table 10 below.

TABLE-US-00010 TABLE 10 Estimated % Sample Dosage bitterness Name (ppm) reduction Comments BB01 50 30% Some bitterness blocking on sides and tip of tongue BB02 50 30% Some blocking on sides and tip of tongue BB03 50 30% Some bitterness blocking on sides and tip of tongue BB04 50 30% Some bitterness blocking on sides and tip of tongue BB05 50 30% Some bitterness blocking on the back of the tongue BB06 50 40% Some bitterness blocking on sides and back of tongue BB07 50 30% Some bitterness blocking on all parts of the tongue BB08 50 30% Some bitterness blocking on front of the tongue BB09 100 60% Nice upfront bitterness reduction with some bitter finish in the end BB10 100 30% Some bitterness blocking on front of the tongue BB11 100 60% Nice upfront bitterness reduction with slight bitterness in the end BB12 100 30% Some bitterness blocking on front and sides of the tongue BB13 100 80% Almost blocked all the bitterness, very smooth finish.

Example 10—Biosynthesis of Flavonoid Glycosides

[0089] Different glycosyltransferases were identified for the preparation of flavonoid glycosides of interest. Specifically, TcCGT1, a putative flavone 8-C-glycosyltransferase from the transcriptome (BioProject accession number PRJNA532685) of Trollius chinensis, described in e of al., “Molecular Characterization and Structural Basis of a Promiscuous C-Glycosyltransferase from Trollius chinensis,” Angew. Chem. Int. Ed., 58(33): 11513-11520 (2019), was used to glycosylate eriodictyol to provide eriodictyol-8-C-β-glucoside (BB013).

[0090] UGT73B2 (Arabidopsis gene At4g34135) described in Willits et al., “Bio-fermentation of modified flavonoids: an example of in vivo diversification of secondary metabolites,” Phytochemistry, 65: 31-41 (2004), and BcGT1 from Bacillus cereus (GenBank accession no. AAS41089.1) described in Chiu et al., “Diversity of sugar acceptor of glycosyltransferase 1 from Bacillus cereus and its application for glucoside synthesis,” Appl. Microbiol. Biotechnol., 100: 4459-4471 (2016), were used to glycosylate eriodictyol and homoeriodictyol to provide homoeriodictyol 7-O-glucoside (BB9), and eriodictyol 7-O-glucoside (BB10), homoeriodictyol 4′-O-glucoside (BB11), eriodictyol 4′-O-glucoside (BB12). The protein sequences of TcCGT1, UGT73B2, and BcGT1 are provided as SEQ ID NO: 1, SEQ ID NO: 3, and SEQ ID NO: 5, respectively (Table 11).

TABLE-US-00011 TABLE 11 Protein Organism Gene Accession No. Sequence ID TcCGT1 Trollius chinensis PRJNA532685 SEQ ID NO: 1 UGT73B2 Arabidopsis thaliana At4g34135 SEQ ID NO: 3 BcGT1 Bacillus cereus AAS41089.1 SEQ ID NO: 5

[0091] The respective TcCGT1 gene, the UGT73B2 gene, and the BcGT1 gene were cloned into expression vectors, then introduced into E. coli W3110 cells with standard chemical transformation protocol. The resulting E. coli strains carrying the target gene were cultivated under conditions known in the art and stored in glycerol at −70° C. until use.

[0092] To produce an E. coli culture suitable for bitter blockier production, glycerol stocks of E. coli W3310 carrying a specific UDP-G glycosyltransferase were removed from −70° C., thawed at room temperature, and cultured in a 50 mL LB culture seed media at 37° C. (termed Seed Culture 1). After 16 hours, Seed Culture 1 was transferred to 2 L of culture seed media, forming Seed Culture 2. Once the cells of Seed Culture 2 produced an OD600 of 5, the cells were transferred to 500 L fermenters, then to a 60 ton production fermenter with modified mineral medium and cultured for 12 hours.

[0093] To begin bitter blocker production, either eriodictyol or homoeriodictyol was added to the culture as substrate together with UDP-glucose and the reaction mixture was allowed to incubate for 24 hours. The reaction mixture was then released from the fermenter for down-stream processing.

[0094] To extract and purify the bitter blocker products, the reaction mixture was centrifuged and the supernatant was transferred to an ion-exchange resin column. The columns were subsequently washed with warm water and eluted with food-grade ethanol. The eluate was then condensed with a wipe-film condenser. The resulting condensate was transferred to a crystallization tank, crystallized by chilling, re-dissolved in water, passed through activated charcoal to remove any fermentation-based colorant, dried in a baking oven, and crushed into a fine powder for further analyses.

[0095] HPLC analysis confirmed production of eriodictyol-8-C-β-glucoside (FIG. 10) from eriodictyol with addition of TcCGT1, production of homoeriodictyol 4′-O-glucoside (FIGS. 3) and homoeriodictyol 7-O-glucoside (FIG. 6) from homoeriodictyol with addition of UGT73B2 or BcGT1, and production of eriodictyol 4′-O-glucoside and eriodictyol 7-O-glucoside from eriodictyol with addition of BcGT1 or UGT73B2. The structure of eriodictyol-8-C-β-glucoside was identified by H-NMR analysis (FIG. 7 and FIG. 8), and the chemical structure is provided in FIG. 9. The structure of homoeriodictyol 4′-O-glucoside was identified by H-NMR (FIG. 1), and the chemical structure is provided in FIG. 2. The structure of homoeriodictyol 7-O-glucoside was identified by H-NMR (FIG. 4), and the chemical structure is provided in FIG. 5.

Example 11—Reducing Bitterness Using BB09, BB11, and BB13

[0096] The bitter blocker candidates BB09, BB11, and BB13 were subject to a two-alternative forced choice (2AFC) difference test wherein panelists were presented Control Caffeine solutions and Test solutions containing caffeine and one of three bitterness blocker candidates (BB09, BB 11, or BB13). Panelists were asked to evaluate the two samples and answer the question, “which one is more hitter?”

[0097] BB09 and BB11 were tested first. Three ounces of control (caffeine in water), BB09 in caffeine water, and BB11 in caffeine water were presented at room temperature in separate plastic souffle cups labeled with 3-digit codes. Ten sensory trained panelists evaluated each sample in three repetitions with a 10 minute break between repetitions. Panelists then completed the 2AFC. Data was collected on EveQuestion and analyzed on XLSTAT. Testing was conducted at Sensations Research according to FEMA guidelines.

[0098] Control (caffeine in water) and BB09 (BB09 in caffeine water) were significantly different from each other in bitterness at a 90% confidence level, with panelists agreeing that the control sample was more bitter than the sample containing BB09 (Table 12). Of the thirty panelist evaluations collected (10 panelists providing 3 evaluations per Test solution), twenty panelist responses identified the control sample as more bitter, as compared to the sample containing BB09 (P=0.0494, 90% CI).

[0099] Control (caffeine in water) and BB11 (BB11 in caffeine water) were significantly different from each other in bitterness at a 90% confidence level, with panelists agreeing that the control sample was more bitter than the sample containing BB11 (Table 12). Of the thirty panelist evaluations collected (10 panelists providing 3 evaluations per Test solution), twenty panelist responses identified the control sample as more bitter, as compared to the sample containing BB11 (P=0.0494, 90% CI).

TABLE-US-00012 TABLE 12 Total # # Re- Selected Selected Control Variant Question? sponses Control Variant Significant? Caffeine BB09 Which is 30 20 10 Yes, in Water more bitter? Control Caffeine BB11 Which is 30 20 10 Yes, in Water more bitter? Control

[0100] BB13 was tested separately. Two ounces of control (caffeine in water), BB13 in caffeine water were presented at room temperature in separate plastic souffle cups labeled with 3-digit codes. Fifteen participants evaluated each sample in two repetitions with a 10 minute break between repetitions for a total of thirty evaluations as per the FEMA guidelines. Panelists then completed the 2AFC to identify the more bitter sample. Data was collected and analyzed on Compusense.

[0101] Of the thirty evaluations, three identified the sample containing BB13 as more bitter. Twenty-seven panelists selected control as more bitter. The control sample was significantly more bitter than the sample containing BB13 at the 90% and 95% confidence interval (FIG. 11). Generally, the panelists described samples containing BB13 as having an initial sweetness that mask the bitterness, less lingering bitterness, and having a nutty taste.

Example 12—Reducing Bitterness of Various Bitter Agonists Using BB09, BB11, and BB13

[0102] The bitter blocker candidates were further characterized using bitter-responsive human taste bud tissue-derived cells (hTBEC) platforms and bioassays. Bitter-responsive hTBECs were treated with hitter blocker candidates and various bitter agonists to assess the efficacy of each bitter blocker candidate in reducing the bitterness of each of the various bitter agonists.

[0103] Four bitter stimuli were used as bitter agonists (Dextromethorphan-HBr, Caffeine, Theobromine, and Rebaudioside A) and three bitter blocker candidates were assessed (Compound A, or BB09; Compound. B, or BB11; and Compound C, or BB13). One industry standard bitter agonist was used as a control (L-Praziquantel), and five bitter blocker controls were used (Senomyx BB68, STX-001, sodium gluconate, eridictyol, and homoeridictyol).

[0104] BB09, BB11, and BB13 were first tested at various concentrations in combination with 100 μM Dextromethorphan-HBr. An ATP secretion detection assay was performed to determine whether the bitter blocker candidates were able to inhibit the luminescence activity of Dextromethorphan-HBr. Both BB11 and BB13 were able to inhibit the luminescence activity of Dextromethorphan-HBr (FIG. 12). Similarly, when using L-Praziquantel as an internal control bitterness stimulus, BB11 and BB13, as well as Senomyx BB68 and STX001 showed inhibition of the L-Praziquantel response in the ATP secretion assay (FIG. 13).

[0105] Next, bitter blocker concentration ranges were narrowed (100 μM-1,000 μM) and compared to a fixed concentration of stimulus. Upper concentrations of BB 13 and STX001 inhibited luminescence signal from both 100 μM Dextromethorphan-HBr (FIG. 14A) and 400 μM L-Praziquantel (FIG. 14B). BB13 was evaluated further by real time ATP secretion detection in pooled hTBEC 66 cells treated with 300 μM Theobromine. Both BB 13 and Senomyx BB68 were able to inhibit the ATP secretion response at 1 mM. Theobromine stimulated a rapid increase in ATP secretion of the hTBEC 66 platform that plateaus after 3-4 minutes and begins to decay after 5 minutes. Both BB13 and Senomyx BB68 attenuated the Theobromine-stimulated signal (FIG. 15).

[0106] Rebaudioside A elicited an ATP secretion response at a concentration of 3 mM, BB09, BB11, BB13, Senomyx BB68, STX001, Homoeridictyol, Eridictyol, and sodium gluconate were tested with Rebaudioside A in pooled hTBEC 56 cultures. BB13 showed the strongest inhibition of Rebaudioside A-induced ATP secretion (FIG. 16). By real time ATP secretion detection, both BB09 and BB13 attenuated Rebaudioside A-induced ATP secretion in pooled hTBEC 56 cultures (FIG. 17).

[0107] With an understanding of the ideal concentrations for bitter agonists and bitter blocker candidates, an ATP secretion detection assay was performed in three separate hTBEC donor cultures (hTBEC 66, hTBEC 56, and hTBEC Donor H). Each culture was treated with BB09, BB11, BB13, STX001, or Senomyx BB68, as well as either Dextromethorphan-HBr at 1000 μM (FIGS. 18A-18C), Theobromine at 1,000 μM (FIGS. 19A-19C), Rebaudioside A at 1 mM (FIGS. 20A-20C), or Caffeine at 3 mM (FIGS. 21A-21C). BB13 showed the most consistent inhibition of the bitter agonists. BB09 and BB11 each showed trends of inhibition in most cases.

[0108] BB13 was further evaluated in all three hTBEC cultures. BB13 consistently showed inhibitory activity against 100 μM Dextromethorphan-HBr (FIG. 22A), as well as against 1,0001 μM Theobromine (FIG. 22B), 1 mM Rebaudioside A (FIG. 23A), 3 mM Caffeine (FIG. 23B), and 400 μM L-Praziquantel (FIG. 24).

[0109] Calcium mobilization response following treatment of 100 μM Dextromethorphan-HBr, 3000 μM Theobromine, and 3 mM Caffeine was evaluated in individual donor-derived hTBECs. At high concentrations, BB13 inhibited calcium mobilization induced by Dextromethorphan-HBr (FIG. 25), as well as that induced by Theobromine (FIG. 26), and Caffeine (FIG. 27).

TABLE-US-00013 Sequences of Interest TcCGT1 Protein SEQ ID NO: 1 MEKSNPNSTSKPHVFLLASPGMGHLIPFLELSKRLVTLNTLQVTLFIVSN EATKARSHLMESSNNFHPDLELVDLTPANLSELLSTDATVFKRIFLITQA AIKDLESRISSMSTPPAALIVDVFSMDAFPVADRFGIKKYVFVTLNAWFL ALTTYVRTLDREIEGEYVDLPEPIAIPGCKPLRPEDVFDPMLSRSSDGYR PYLGMSERLTKADGLLLNTWEALEPVSLKALRENEKLNQIMTPPLYPVGP VARTTVQEVVGNECLDWLSKQPTESVLYVALGSGGIISYKQMTELAWGLE MSRQRFIWVVRLPTMEKDGACRFFSDVNVKGPLEYLPEGFLDRNKELGMV LPNWGPQDAILAHPSTGGFLSHCGWNSSLESIVNGVPVIAWPLYAEQKMN ATLLTEELGVAVRPEVLPTKAVVSRDEIEKMVRRVIESKEGKMKRNRARS VOSDALKAIEKGGSSYNTLIEVAKEFEKNHKVL TCCGT1 DNA SEQ ID NO: 2 ATGGAGAAGTCAAATCCAAATTCGACTICAAAGCCGCATGTATTCCTGCT GGCGAGCCCGGGGATGGGCCACTTAATCCCGTTTCTCGAGTTATCAAAGC GGCTGGTGACCTTAAATACCTTACAGGTAACCTTATTCATCGTATCAAAC GAAGCTACTAAAGCGCGGTCACATCTGATGGAATCATCAAATAATTTCCA CCCAGATCTGGAATTAGTGGATTTAACCCCGGCGAATTTATCAGAGTTAC TGAGCACTGACGCGACCGTATTCAAACGGATCTTCTTAATCACCCAGGCT GCTATTAAAGACCTGGAATCACGCATTAGCTCAATGAGTACCCCGCCGGC GGCGTTAATCGTAGACGTATTCTCGATGGACGCCTTTCCGGTGGCGGATC GTTTTGGCATCAAGAAGTATGTCTTTGTGACCTTAAACGCGTGGTTTCTG GCGCTGACCACCTACGTACGGACCCTGGATCGGGAAATTGAAGGCGAGTA TGTGGATCTGCCGGAGCCGATTGCGATCCCGGGCTGCAAACCGTTACGGC CAGAGGACGTGTTTGACCCGATGCTGAGCCGTAGCAGCGATGGGTATCGC CCGTACCTGGGGATGAGCGAGCGTTTAACCAAGGCGGATGGGCTGCTGCT GAATACCTGGGAAGCCTTAGAGCCAGTCTCGCTGAAGGCGCTGCGCGAAA ACGAGAAATTAAACCAAATCATGACTCCGCCGCTGTACCCAGTGGGCCCG GTCGCGCGGACCACCGTCCAAGAGGTCGTCGGGAACGAGTGTCTGGATTG GTTATCGAAGCAGCCAACCGAGICAGTACTGTACGTAGCCCTGGGCAGCG GCGGGATCATTTCATACAAACAGATGACTGAGTTAGCGTGGGGCCTGGAA ATGTCGCGGCAGCGGTTTATCTGGGTCGTGCGGTTACCAACTATGGAGAA AGACGGGGCCTGCCGGTTCTTTTCAGACGTGAACGTCAAAGGGCCGCTGG AATACCTGCCAGAAGGGTTCCTGGACCGGAACAAGGAGCTGGGCATGGTC TTACCGAACTGGGGGCCGCAGGACGCCATCCTGGCTCATCCGAGTACTGG CGGCTTTCTCTCACATTGCGGCTGGAACTCATCACTGGAGTCGATTGTCA ATGGCGTCCCGGTCATCGCGTGGCCGCTGTACGCGGAGCAGAAAATGAAT GCTACCCTGCTGACCGAAGAGTTAGGCGTGGCCGTACGGCCGGAAGTCTT ACCGACTAAGGCGGTCGICAGCCGTGATGAGATCGAGAAAATGGTCCGTC GCGTAATCGAAAGCAAGGAAGGGAAAATGAAGCGCAACCGCGCTCGCAGC GTACAAAGCGATGCGCTGAAAGCGATTGAAAAGGGGGGGTCAAGCTATAA CACCTTAATCGAGGTCGCAAAGGAGTTCGAGAAGAACCACAAAGTACTG UGT73B2 Protein SEQ ID NO: 3 MGSDHHHRKLHVMFFPFMAYGHMIPTLDMAKLFSSRGAKSTILTTSLNSK ILQKPIDTFKNLNPGLEIDIQIFNFPCVELGLPEGCENVDFFTSNNNDDK NEMIVKFFFSTRFFKDQLEKLLGTTRPDCLIADMFFPWATEAAGKFNVPR LVFHGTGYFSLCAGYCIGVHKPQKRVASSSEPFVIPELPGNIVITEEQII DGDGESDMGKFMTEVRESEVKSSGVVLNSFYELEHDYADFYKSCVQKRAW HIGPLSVYNRGFEEKAERGKKANIDEAECLKWLDSKKPNSVIYVSFGSVA FFKNEQLFEIAAGLEASGTSFIWVVRKTKDDREEWLPEGFEERVKGKGMI IRGWAPQVLILDHQATGGFVTHCGWNSLLEGVAAGLPMVTWPVGAEQFYN EKLVTQVLRTGVSVGASKHMKVMMGDFISREKVDKAVREVLAGEAAEERR RRAKKLAAMAKAAVEEGGSSFNDLNSFMEEFSS UGT73B2 DNA SEQ ID NO: 4 ATGGGTTCAGACCACCACCACCGCAAACTGCACGTTATGTTCTTCCCGTT TATGGCTTACGGCCACATGATTCCGACGCTGGATATGGCGAAACTGTTCA GCTCTCGTGGTGCCAAAAGCACCATCCTGACCACGTCTCTGAATAGTAAA ATCCTGCAGAAACCGATTGATACGTTTAAAAATCTGAACCCGGGCCTGGA AATTGACATCCAAATTTTCAACTTTCCGTGCGTTGAACTGGGCCTGCCGG AAGGTTGTGAAAATGTCGATTTCTTTACCTCCAACAATAACGATGACAAA AACGAAATGATCGTGAAATTTTTCTTTTCAACGCGTTTCTTTAAAGATCA GCTGGAAAAACTGCTGGGTACCACGCGCCCGGATTGCCTGATTGCGGACA TGTTCTTTCCGTGGGCCACCGAAGCGGCCGGCAAATTTAATGTGCCGCGT CTGGTTTTCCATGGCACGGGTTATTTTTCGCTGTGCGCAGGCTACTGTAT CGGTGTGCACAAACCGCAGAAACGCGTTGCTAGTTCCTCAGAACCGTTCG TCATTCCGGAACTGCCGGGTAACATCGTGATCACCGAAGAACAAATCATC GATGGCGACGGTGAATCAGATATGGGTAAATTTATGACCGAAGTTCGTGA ATCGGAAGTCAAATCGAGCGGCGTGGTTCTGAACAGCTTCTATGAACTGG AACATGATTATGCGGACTTTTACAAATCTTGCGTCCAGAAACGCGCCTGG CACATTGGCCCGCTGAGTGTTTACAATCGTGGTTTTGAAGAAAAAGCGGA ACGCGGCAAAAAAGCGAACATCGATGAAGCCGAATGTCTGAAATGGCTGG ACTCCAAAAAACCGAACAGCGTGATTTATGTTTCCTTCGGCTCAGTTGCC TTCTTTAAAAACGAACAGCTGTTTGAAATCGCAGCTGGCCTGGAAGCATC GGGTACCAGCTTCATTTGGGTCGTGCGTAAAACGAAAGATGACCGCGAAG AATGGCTGCCGGAAGGTTTTGAAGAACGTGTGAAAGGCAAGGGTATGATT ATCCGTGGTTGGGCACCGCAGGTGCTGATCCTGGATCATCAAGCTACCGG CGGTTTCGTTACGCACTGTGGTTGGAACAGCCTGCTGGAAGGCGTGGCAG CAGGTCTGCCGATGGTCACCTGGCCGGTGGGCGCGGAACAGTTTTACAAC GAAAAACTGGTCACCCAAGTGCTGCGCACGGGCGTTTCTGTCGGTGCCAG TAAACACATGAAAGTGATGATGGGTGATTTCATTAGTCGTGAAAAAGTTG ACAAAGCAGTTCGCGAAGTCCTGGCTGGCGAAGCAGCTGAAGAACGTCGC CGTCGCGCGAAAAAACTGGCGGCCATGGCTAAAGCAGCTGTGGAAGAAGG CGGCAGCAGTTTTAATGACCTGAATAGTTTTATGGAAGAATTTAGTTCGT GA BcGT1 Protein SEQ ID NO: 5 MANVLVINFPGEGHINPTLAIVSELIRRGETVVSYCIEDYRKKIEATGAQ FRVFENFLSQINIMERVNEGGSPLTMLSHMMEASERIVTQIVEETKGEKY DYLIYDNHFPVGRIIANVLKLPSVSSCTTFAFNQYITFNDEHESREVDET NPLYQSCLAGMEKWNKQYGMKCNSMYDIMNHPGDITIVYTSKEYQPRSDV FDESYKFVGPSIATRKEVGSFPMEDLKDEKLIFISMGTVFNEQPELYEKC FEAFKDVEATVVLVVGKKINISQFENIPNNFKLYNYVPQLELLQYADVFV THGGMNSSSEALYYGVPLVVIPVTGDQPLVAKRVNEVGAGIRLNRKELTS EMLRESVKKVMDDVTFKEKSRKVGESLRNAGGYNRAVDEILKMNSYSKLK BcGT1 DNA SEQ ID NO: 6 ATGGCAAACGTACTCGTAATAAATTTCCCTGGAGAAGGTCATATAAATCC GACTTTAGCTATTGTAAGTGAGTTAATTCGGCGAGGGGAGACAGTTGTTT CGTATTGTATTGAAGATTATAGAAAGAAGATTGAAGCAACAGGTGCACAA TTCCGAGTGTTTGAGAATTTCCTCTCTCAAATTAATATTATGGAGCGAGT AAATGAAGGTGGGAGTCCTTTGACGATGCTGTCTCACATGATGGAAGCAT CAGAACGTATTGTTACTCAAATTGTAGAAGAAACAAAAGGGGAAAAGTAC GATTATTTGATATATGATAATCACTTTCCAGTAGGACGTATTATAGCCAA TGTTTTAAAGTTACCTAGTGTTTCTTCTTGTACAACGTTTGCTTTTAATC AGTACATTACTTTTAACGATGAACATGAATCAAGAGAAGTAGATGAAACG AATCCATTGTATCAATCTTGTTTAGCGGGAATGGAAAAATGGAACAAACA GTATGGAATGAAATGTAATAGTATGTATGATATTATGAACCATCCTGGTG ATATTACAATTGTGTATACTTCAAAGGAATATCAGCCGCGTTCAGATGTA TTCGATGAATCGTATAAGTTTGTTGGCCCATCAATTGCTACTCGAAAAGA AGTAGGTAGCTTTCCTATGGAAGATTTAAAAGATGAAAAATTGATTTTCA TTTCTATGGGAACAGTTTTTAATGAACAACCTGAGTTATATGAAAAATGT TTTGAAGCGTTTAAAGATGTAGAAGCGACAGTCGTATTAGTTGTTGGTAA GAAGATAAATTAGAACTATTACAGTATGCTGATGTATTCGTAACACACGG CGGTATGAATAGTTCAAGTGAAGCACTATATTACGGTGTCCCGTTAGTTG TAATTCCGGTAACAGGAGATCAGCCTTTAGTTGCGAAACGAGTAAATGAA GTAGGGGCTGGAATAAGGCTTAATCGCAAAGAATTAACTTCTGAAATGTT ACGTGAGTCTGTAAAGAAAGTGATGGATGATGTAACGTTTAAGGAAAAAA GTCGTAAAGTTGGAGAGTCACTTCGAAATGCTGGTGGTTATAATAGGGCA GTTGATGAAATATTAAAAATGAATTCATACTCAAAACTTAAATAA