CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to US App. No. 63/053293, filed July 17, 2020, entitled Zinc Ascorbate Glycinate Co-Salt, and which is incorporated herein by reference.

STATEMENT REGARDING FEDERALLY

SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not Applicable.

BACKGROUND [0003] This application relates to a novel divalent metal ascorbate glycinate co-salt compound, which incorporates an equal molar ratio of ascorbic acid and glycine, completely neutralized with a divalent metal in a metal to ligand ratio (i.e., a metal :ascorbate:glycinate ratio) of 1 :1 :1.

[0004] Divalent metals, such as calcium, magnesium, and zinc, are important for human health. The importance of calcium in cellular biochemistry is well known. Also well-known is the importance of trace minerals, such as magnesium, and zinc, to human health. For example, many studies show that zinc supplementation can lessen the severity of the common cold and is beneficial to the human immune system ^{1 4} . [0005] Other compounds are important as well. Glycine (NH ₂ -GH ₂ -COOH) is believed to be beneficial in reducing oxidative stress through production of glutathione in the body ⁵⁷ . Further, glycine is used by the body to produce creatine, a substance shown to increase muscle size, strength, and power ^{8 10} . Glycine and has also been studied for its beneficial effects on bone health, brain function and neurological conditions like Parkinson’s and Alzheimer’s disease ^{7 10} . Glycine is a major constituent of collagen, which is known to promote skin health, relief of joint pain and prevention of bone loss ^{11 18} . Other studies also show that glycine may also benefit sleep quality and mental cognition ^{19 22} . The benefits of ascorbic acid (vitamin C) are well known and documented. [0006] It would be desirable to provide a compound that can deliver both glycine and minerals, for example, by ingestion.

BRIEF SUMMARY

[0007] We have developed a new co-salt that delivers a divalent metal (such as Ca ⁺² , Mg ⁺² , or Zn ⁺² ), ascorbic acid (vitamin C) and glycine in a single water-soluble dosage unit without the need for blending or combining multiple components.

[0008] Briefly, a divalent metal ascorbate glycinate co-salt, and hydrates thereof. As a hydrate, the divalent metal ascorbate glycinate co-salt has a formula of MCsHnNOs · X H2O. The co-salt, in anhydrous form, is believed to have the following general structure:

[0009] The zinc, magnesium, and calcium ascorbate glycinate co-salts are thus believed to have the following structures:

[0010] The molar quantity of ascorbic acid and glycine in the co-salt is 1 :1 and the metahligand, or metal :ascorbic acid:glycine, ratio is 1 :1 :1.

[0011] The divalent metal ascorbate glycinate co-salt has a metal content of about 8% to about 21% on an anhydrous basis.

[0012] Preferably, the divalent metal glycinate co-salt, when dried, is in powder form and contains up to about 20% water. [0013] The source of metal for the co-salt is a metal, a metal oxide, a metal hydroxide or a metal carbonate. The preferred source of the metal depends on the metal chosen. A preferred zinc source, for example, is zinc oxide (ZnO). The co-salt (in aqueous form) wherein the source for the metal (M) is a metal oxide (MO) is defined by the following equation:

MO + C ₆ H ₈ O _6(aq) + C ₂ H ₅ N0 _2(aq) MC ₈ H ₁₁ NO _8(aq) + H ₂ O _(l) . [0014] The 1 :1 molar ratio of citric acid and glycine in the aqueous solution is neutralized with a 90 - 110% 1 molar metal equivalence.

[0015] The neutralized solution is dried to a free-flowing powder.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIGS 1 and 2 are infrared spectroscopy (FT-IR) spectra for Zinc Bis-glycinate and Zinc Ascorbate, respectively;

[0017] FIG. 3 is an FT-IR spectrum for a “Component Dry Blend” of Zinc Bis-glycinate and Zinc Ascorbate;

[0018] FIGS. 4 and 5 are FT-IR spectrum of Examples A and B, respectively of Zinc Ascorbate Glycinate Co-salt; [0019] FIGS. 6 and 7 are Scanning Electron Microscope (SEM) images of

Zinc Bis-Glycinate and Zinc Ascorbate, respectively;

[0020] FIG. 8 as an SEM image of Zinc Ascorbate Glycinate Co-Salt;

[0021] FIGS. 9 and 10 are x-ray diffraction (XRD) Patterns of Zinc Bis- Glycinate and Zinc Ascorbate, respectively; [0022] FIG. 11 is an XRD Pattern of the “Component Dry Blend”;

[0023] FIGS. 12 and 13 are XRD Analyses of Examples A and B, respectively, of Zinc Ascorbate Glycinate Co-Salt; [0024] FIG. 14 is a chart of FT-IR spectra comparing calcium ascorbate glycinate co-salt, calcium ascorbate, calcium bisglycinate, and a 1 :1 dry mix of calcium ascorbate and calcium bisglycinate;

[0025] FIGS. 15A-D are XRD patterns of calcium ascorbate glycinate co- salt, calcium ascorbate, calcium bisglycinate, and a 1 :1 dry mix of calcium ascorbate and calcium bisglycinate, respectively;

[0026] FIG. 16 is a chart of FT-IR spectra comparing magnesium ascorbate glycinate co-salt, Magnesium ascorbate, Magnesium bisglycinate, and a 1 :1 dry mix of magnesium ascorbate and magnesium bisglycinate; and [0027] FIGS. 17A-D are XRD patterns of magnesium ascorbate glycinate co-salt, magnesium ascorbate, magnesium bisglycinate, and a 1 :1 dry mix of magnesium ascorbate and magnesium bisglycinate, respectively.

[0028] Corresponding reference numerals will be used throughout the several figures of the drawings. DETAILED DESCRIPTION

[0029] The following detailed description illustrates the claimed invention by way of example and not by way of limitation. This description will clearly enable one skilled in the art to make and use the claimed invention, and describes several embodiments, adaptations, variations, alternatives and uses of the claimed invention, including what we presently believe is the best mode of carrying out the claimed invention. Additionally, it is to be understood that the claimed invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. The claimed invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. [0030] Several laboratory samples of the novel divalent metal ascorbate glycinate co-salt were prepared for use in demonstrating both matter of composition and comparative studies against both metal ascorbate and metal glycinate (i.e., zinc ascorbate and zinc glycinate). [0031] An aqueous divalent metal ascorbate glycinate co-salt is formed by combining anhydrous ascorbic acid ( C ₆ H ₈ O ₆ ) and glycine (C ₂ H ₅ NO ₂ ) in a 1 :1 molar ratio, and neutralizing the aqueous solution with 90 - 110% of a 1 molar divalent metal equivalence. The metal source is the metal, a metal oxide, a metal hydroxide or a metal carbonate. Thus, for example, for a zinc ascorbate glycinate co-salt, the source for the zinc would be a zinc, zinc oxide, zinc hydroxide or zinc carbonate. The divalent metal ascorbate glycinate co-salt when prepared has a molecular formula of MC ₈ H ₉ NO ₈ as shown below: and is formed by the following basic reaction: where M is Ca, Mg, or Zn derived from a metal, hydroxide, oxide or carbonate. [0032] The production of an aqueous solution of the divalent metal ascorbate glycinate co-salt, wherein an oxide is the metal source, is shown in Equation 1 and by drying to a free-flowing powder in Equation 2.

Eq. 1 : MO + C ₆ H ₈ O _6(aq) + C ₂ H ₅ NO _2(aq) → MC ₈ H ₁₁ NO _8(aq) + H ₂ O _(l) Eq. 2: MC ₈ H ₁₁ NO _8(aq) → MC ₈ H ₁₁ NO ₈ · X H ₂ O (Drying Step)

[0033] As is known, the value of X in Equation 2 above depends on the extent of drying of the co-salt during the drying step.

[0034] The divalent metal ascorbate glycinate co-salt is believed to have the following general structure: wherein M is Ca, Mg, and Zn.

[0035] The zinc, magnesium, and calcium ascorbate glycinate co-salts are thus believed to have the following structures:

[0036] The anhydrous co-salts have molecular weights and a wt% metal content as shown in Table I below. TABLE I

[0037] The co-salt typically is found to contain between 0.0 - 20.0% water depending on extent of drying.

[0038] To demonstrate matter of composition and product superiority of the co-salts, classical chemistry methodology (assay), infrared spectroscopy (FT- IR), electron microscopy (SEM) and X-ray diffraction (XRD) were implemented. EXAMPLES:

1. Zinc Ascorbate Glycinate Co-salt

A. Lab Scale Preparation of Zinc Ascorbate Glycinate Co-salt.

[0039] A reaction mixture was prepared comprising 176.12g (1 mol) anhydrous ascorbic acid and 75.01 g (1 mol) glycine dissolved in 1000g of water. The mixture was heated to about 60-80°C. The resulting acid solution was neutralized with 81 .4g (1 mol) of zinc oxide and digested with agitation at about 60-80°C until complete reaction was achieved (between 1-4 hours). The resulting reaction mass contained 314.56g (1 mol) of zinc ascorbate glycinate co-salt having a metal to ligand (metal:ascorbate:glycine) ratio of 1 :1 :1 remaining in solution. The reaction mass was filtered to remove any unreacted zinc oxide and other extraneous matter. The filtrate was dried to produce a free-flowing powder containing zinc ascorbate glycinate co-salt having a metal to ligand ratio of 1 :1 :1 and a moisture content of 0.0-20.0%.

B. Pilot Plant Scale Preparation of Zinc Ascorbate Glycinate Co-salt.

[0040] A reaction mixture was prepared comprising 3.52 Kg (20 mol) anhydrous ascorbic acid and 1.5 Kg (20 mol) glycine dissolved in 20Kg of water. The mixture was heated to about 60-80°C. The resulting acid solution was neutralized with 1.6 Kg (20 mol) of zinc oxide and digested with agitation at about 60-80°C until complete reaction was achieved (between 1 -4 hours). The resulting reaction mass contained 6.3 Kg (20 mol) of zinc ascorbate glycinate co-salt having a metal to ligand ratio of 1 :1 :1 remaining in solution. The reaction mass was filtered to remove any unreacted zinc oxide and other extraneous matter. The filtrate was dried to produce a free-flowing powder containing zinc ascorbate glycinate co-salt having a metal to ligand ratio of 1 :1 :1 and a moisture content of 0.0-20.0%. [0041] To assist in matter of composition and comparison, a dry blend was prepared by mixing 0.5 mole of zinc glycinate with 0.5 mole of zinc ascorbate. This sample will further be referred to as the “component dry blend” and will be used to help demonstrate the novel zinc ascorbate glycinate co-salt’s composition.

[0042] Classical Chemistry Methodology

[0043] Research samples of zinc ascorbate glycinate co-salts lab scale sample A and pilot scale sample B were prepared and analyzed for zinc content using EDTA titration and Eriochrome Black T (EBT) indicator solution. The water content of both samples was determined by Thermogravimetric Analysis (TGA) so that the anhydrous zinc content could be calculated and compared to theoretical anhydrous magnesium content. The sample data shown in Table 2, below, shows the theoretical amount of zinc that is consistent with the zinc ascorbate glycinate co-salt formula. Table 2

Zinc Content, Water Content and Theoretical Assay values for Zinc Ascorbate Glycinate Co-salts

FT-IR Spectroscopy

[0044] Infrared spectroscopy shown in FIGS. 1 -4 was employed to demonstrate the uniqueness of the zinc ascorbate glycinate co-salt against zinc glycinate, zinc ascorbate and the “component dry blend” described above. Zinc Bis-glycinate (FIG. 1) shows strong absorbances in the fingerprint region of 1560, 1400, 1050, 700 cnr ¹ and distribution of strong absorbances between approximately 626 and 720 cm ¹ . [0045] Zinc Ascorbate (FIG. 2) has strong absorbances in the fingerprint region of 1600, 1500, 1110 and 1026cnr ¹ and a distribution of weaker less defined absorbances between approximately 630 and 760 cm ^-1 .

[0046] The “Component Dry Blend” (FIG. 3) has strong absorbances in the fingerprint region of 1560, 1460, 1126 and 756 cm ^-1 . Looking closer at its strong absorptions and peak shapes, one skilled in the art would discern that this is indeed a physical blend as both aspects of the independent spectra (FIGS. 1 and 2) are visible yet muted by each other.

[0047] The FT-IR spectrum for zinc ascorbate glycinate co-salt samples A and B are shown in FIGS. 4 and 5. The co-salts have strong yet weakly defined absorbances in the fingerprint region at 1540 and strong broadened absorbances at 1110 and 1030 cm ¹ , taking note that the sharp absorbances between 750- 1350 cm ^-1 found in FIGS. 1-3 are either gone have been substantially broadened. [0048] Examination of the FT-IR spectra of the “component dry blend” in

FIG. 3 and the zinc ascorbate glycinate co-salts in FIGS. 4 and 5 one skilled in the art will notice that they are substantially different, providing strong evidence that the co-salt is a unique entity and not a mere blend of components. Particle Morphology by Scanning Electron Microscopy

[0049] The unique nature of the zinc ascorbate glycinate co-salt can be both demonstrated and differentiated from magnesium citrate tribasic and magnesium glycinate. FIGS. 6 - 8 show SEM (Scanning Electron Microscopy) imaging of zinc bis-glycinate, zinc ascorbate and zinc ascorbate glycinate co- salt, respectively.

[0050] As shown in FIG. 6, zinc bis-glycinate has a highly crystalline presentation, composed of many rod-shaped crystallites of varying size and orientation. SEM imaging of zinc ascorbate shown in FIG. 7 shows a polymorphic type of crystallinity that is densely packed.

[0051] SEM imagery of zinc ascorbate glycinate co-salt, shown in FIG. 8, demonstrates the amorphous nature of this product. One skilled in the art will also realize the porous nature of the solids.

[0052] Lack of either the porous polycrystalline crystallites found in zinc ascorbate or rod type crystallites found in zinc bis-glycinate demonstrate that this co-salt is not a mere co-precipitated blend of zinc ascorbate and zinc bis- glycinate, but a unique chemical entity or compound. X-Ray Diffraction (XRD) Pattern Analysis

[0053] As evidenced from Thermogravimetric Analysis and Particle Morphology by Scanning Electron Microscopy, zinc bis-glycinate and zinc ascorbate are relatively high crystalline materials and as such have very distinct and reproducible XRD patterns as shown in FIGS. 9 and 10. The baseline of the zinc ascorbate XRD pattern is higher and gives less defined theta signals due to the polymorphic nature of the crystals.

[0054] The “component dry blend” described above displays distinct high crystalline XRD patterns consistent with both zinc bis-glycinate and zinc ascorbate as shown in FIG. 11 . [0055] Due to the amorphous nature of zinc ascorbate glycinate co-salt as evidenced from Particle Morphology by Scanning Electron Microscopy, this compound does not show any degree of crystallinity by XRD as shown in FIGS. 12 and 13. The fact that the “component dry blend” shows both zinc bis-glycinate and zinc ascorbate theta signals and the zinc ascorbate glycinate co-salt does not, provides strong evidence that the zinc ascorbate glycinate co-salt is a unique entity and not a mere blend of components. Zinc Ascorbate Glvcinate Solubility Experiment

[0056] It was discovered that zinc ascorbate glycinate co-salt was soluble in acetone, but zinc ascorbate, zinc bisglycinate and glycine were not. This is further evidence that zinc ascorbate glycinate has distinct properties from zinc ascorbate, zinc bisglycinate and glycine. Zinc ascorbate glycinate co-salt is a unique compound and not a mixture of bi-products or raw materials.

2. Calcium Ascorbate Glycinate Co-salt

[0057] A typical lab scale (1 mol scale) preparation of calcium ascorbate glycinate co-salt was prepared as follows: A reaction mixture was prepared comprising 176.12g (1 mol) anhydrous ascorbic acid and 75.01 g (1 mol) glycine dissolved in 1000g of water. The mixture was heated to 60-80°C. The resulting acid solution was neutralized with 75.6g (1 mol) of ultra-pure calcium hydroxide (to avoid any decomposition of ascorbic acid due to trace iron or copper impurities) and digested with agitation at 60-80°C until complete reaction was achieved, between 1-4 hours. The resulting reaction mass contained 289.25g (1 mol) of calcium ascorbate glycinate co-salt having a metal to ligand ratio of 1 :1 :1 remaining in solution. The reaction mass was filtered to remove any unreacted calcium hydroxide and other extraneous matter. The filtrate was dried to produce a free-flowing beige to yellow powder containing calcium ascorbate glycinate co-salt having a metal to ligand ratio of 1 :1 :1 and a moisture content of 0.0-20.0%.

[0058] Table 3 below shows analytical data for the calcium ascorbate glycinate produced above, and FIG. 14 shows FT-IR spectra comparisons for the calcium ascorbate glycinate co-salt vs. calcium ascorbate, calcium bisglycinate and a 1 :1 dry mix of calcium ascorbate and calcium bisglycinate. FIGS. 15A-D show XRD patterns of the calcium ascorbate glycinate co-salt vs. calcium ascorbate, calcium bisglycinate and a 1 :1 dry mix of calcium ascorbate and calcium bisglycinate. TABLE 3

[0059] FIG. 14 shows the FT-IR comparisons of Calcium Ascorbate Glycinate co-salt (line 4), calcium ascorbate (line 2), calcium bisglycinate (line 3) and a 1 :1 dry mix of calcium ascorbate and calcium bisglycinate (line 1 ). As seen, the co-salt produces an FT-IR spectrum different from calcium ascorbate, calcium glycinate, and 1 :1 mix of calcium ascorbate and calcium glycinate. FIGS. 15A-D show XRD patterns for Calcium Ascorbate Glycinate co-salt, calcium ascorbate, calcium bisglycinate and a 1 :1 dry mix of calcium ascorbate and calcium bisglycinate, respectively. Again, as seen, the XRD pattern for the co-salt is different from the XRD patterns for calcium ascorbate, calcium glycinate, and 1 :1 mix of calcium ascorbate and calcium glycinate. These comparisons show that the co-salt is a unique compound and not a mixture of bi-products or raw materials.

3. Magnesium Ascorbate Glycinate [0060] A typical lab scale (1 mol scale) preparation of magnesium ascorbate glycinate co-salt follows: A reaction mixture was prepared comprising 176.12g (1 mol) anhydrous ascorbic acid and 75.01 g (1 mol) glycine dissolved in 1000g of water. The mixture was heated to 60-80°C. The resulting acid solution was neutralized with 41.1g (1 mol) of ultra-pure magnesium oxide (to avoid any decomposition of ascorbic acid due to trace iron or copper impurities) and digested with agitation at 60-80°C until complete reaction was achieved between 1-4 hours. The resulting reaction mass contained 273.48g of magnesium ascorbate glycinate co-salt having a metal to ligand ratio of 1 :1 :1 remaining in solution. The reaction mass was filtered to remove any unreacted magnesium oxide and other extraneous matter. The filtrate was dried to produce a free-flowing yellow to butterscotch colored powder containing magnesium ascorbate glycinate co-salt having a metal to ligand ratio of 1 :1 :1 and a moisture content of 0.0 - 20.0%.

[0061] Table 4 below shows analytical data for magnesium ascorbate glycinate. FIG. 16 shows FT-IR spectra comparing magnesium ascorbate glycinate co-salt vs. magnesium ascorbate, magnesium bisglycinate and a 1 :1 dry mix of magnesium ascorbate and magnesium bisglycinate. FIGS. 17A-D show XRD patterns of magnesium ascorbate glycinate co-salt vs. magnesium ascorbate, magnesium bisglycinate and a 1 :1 dry mix of magnesium ascorbate and magnesium bisglycinate. TABLE 4

[0062] FIG. 16 shows the FT-IR spectra comparisons of magnesium ascorbate glycinate co-salt (line 6), Magnesium ascorbate (line 7), Magnesium bisglycinate (line 8) and a 1 :1 dry mix of magnesium ascorbate and calcium bisglycinate (line 5). As seen, the co-salt produces an FT-IR spectrum different from magnesium ascorbate, magnesium glycinate, and 1 :1 mix of magnesium ascorbate and magnesium glycinate. FIGS. 17A-D show XRD patterns for magnesium ascorbate glycinate co-salt, magnesium ascorbate, magnesium bisglycinate, and a 1 :1 dry mix of Magnesium ascorbate and Magnesium bisglycinate, respectively. Again, as seen, the XRD pattern for the co-salt is different from the XRD patterns for magnesium ascorbate, magnesium glycinate, and 1 :1 mix of magnesium ascorbate and magnesium glycinate. These comparisons show that the co-salt is a unique compound and not a mixture of bi-products or raw materials. [0063] In view of the above, it will be seen that the several objects and advantages of the present invention have been achieved and other advantageous results have been obtained.

[0064] As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

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