What Is Calcium Alpha-Ketoglutarate (Ca-AKG)?

Calcium Alpha-Ketoglutarate, commonly abbreviated as Ca-AKG or CaAKG, is the calcium salt form of alpha-ketoglutaric acid (AKG), a naturally occurring intermediate in the tricarboxylic acid (TCA) cycle — also known as the Krebs cycle — which drives cellular energy production in virtually every living organism. With CAS number 71686-01-6 and a molecular formula of C₅H₄CaO₅·H₂O, Ca-AKG presents as a white to off-white fine powder with a molecular weight of approximately 184.16 g/mol.

As a raw material ingredient, Ca-AKG has gained significant traction in the global nutraceutical supply chain. Its unique dual-functionality — delivering both biologically active AKG and nutritional calcium — makes it a compelling choice for formulators developing products in the anti-aging, sports nutrition, metabolic health, and bone support categories.

Ca-AKG Raw Ingredient Specifications

For B2B procurement and formulation purposes, the following table summarizes the typical technical specifications of premium-grade Calcium Alpha-Ketoglutarate powder:

Parameter	Specification
Product Name	Calcium Alpha-Ketoglutarate (Ca-AKG)
CAS Number	71686-01-6
Molecular Formula	C₅H₄CaO₅·H₂O
Molecular Weight	~184.16 g/mol (anhydrous)
Purity	≥ 98% (HPLC) / ≥ 99% available
Calcium Content	18–21%
Appearance	White to off-white crystalline powder
Solubility	Water-soluble; readily soluble in acidic solutions
Drying Loss	≤ 7%
pH Value	6.0–8.0
Heavy Metals (Total)	≤ 10 ppm
Arsenic	≤ 3 ppm
Lead	≤ 2 ppm
Mercury	≤ 2 ppm
Total Plate Count	≤ 1,000 CFU/g
Storage	Store in cool, dry, dark place; seal tightly
Certifications	Halal, Kosher, ISO9001, FSSC 22000

How Ca-AKG Works: Mechanism of Action

1. Krebs Cycle Enhancement and Cellular Energy

Alpha-ketoglutarate is a pivotal intermediate in the TCA cycle, where it participates in the oxidative decarboxylation that drives ATP and GTP production — the fundamental energy currencies of the cell. By supplementing Ca-AKG, formulators can supply exogenous AKG to support mitochondrial function, particularly in aging cells where endogenous AKG production may decline. Studies in aging mouse models have demonstrated that AKG supplementation can extend lifespan and compress morbidity, with the compound influencing multiple pathways related to cellular energy metabolism.

2. Amino Acid Metabolism and Nitrogen Balance

Beyond energy production, AKG serves as the primary carbon skeleton for nitrogen assimilation reactions in the body. It plays a central role in the transamination of amino acids, facilitating the synthesis of glutamate and glutamine — two amino acids critical for immune function, muscle recovery, and neurotransmitter synthesis. This makes Ca-AKG an especially valuable ingredient for sports nutrition formulations targeting muscle protein synthesis and post-exercise recovery.

3. Antioxidant and Anti-Aging Pathways

Emerging research indicates that AKG modulates signaling pathways and epigenetic markers associated with aging. It helps reduce oxidative stress by neutralizing free radicals, supports cellular repair mechanisms, and influences the activity of prolyl hydroxylase enzymes involved in hypoxia-inducible factor (HIF) regulation. A landmark 2020 study published in Cell Metabolism showed that AKG supplementation in aging mice extended median lifespan by approximately 12% and improved multiple measures of healthspan.

4. Calcium Delivery for Skeletal Health

The calcium component of Ca-AKG provides 18–21% elemental calcium by weight, contributing to bone mineral density and supporting normal muscle contraction and nerve transmission. Compared to inorganic calcium sources like calcium carbonate (which has ~30% bioavailability), the organic calcium in Ca-AKG benefits from AKG-mediated transport mechanisms, potentially improving absorption and utilization.

Ca-AKG vs. Other AKG Forms: A Formulator's Comparison

When selecting an AKG raw ingredient, formulators encounter several variants. Understanding the distinctions is critical for matching ingredient to application:

Feature	Ca-AKG	Free AKG Acid	AAKG
Primary Components	Calcium + AKG	Alpha-ketoglutaric acid	L-Arginine + AKG
CAS Number	71686-01-6	328-50-7	16856-18-1
Calcium Content	18–21%	None	None
Key Advantage	Dual benefit: AKG + calcium	Pure AKG delivery	Nitric oxide precursor support
Primary Applications	Anti-aging, bone health	Metabolic health, research	Bodybuilding, vascularity
Stability	High (salt form)	Moderate (hygroscopic)	Moderate
Taste Profile	Mildly acidic, neutral	Strongly acidic	Mildly bitter

Applications and End-Use Markets

Anti-Aging and Longevity Supplements

The anti-aging market represents the fastest-growing application for Ca-AKG. Research published in 2021 demonstrated that a formulation containing alpha-ketoglutarate and vitamins conferred an average 8-year reduction in biological aging (as measured by TruAge DNA methylation testing) after approximately 7 months of use. This has catalyzed demand from longevity-focused supplement brands seeking high-purity Ca-AKG for capsule, tablet, and liposomal formulations.

Sports Nutrition and Athletic Performance

Ca-AKG supports energy metabolism, muscle recovery, and reduced muscle soreness through its role in the Krebs cycle and amino acid metabolism. Typical dosage for athletic applications ranges from 3–6 g per day, often split around workout sessions. Its ability to deliver both energy-supporting AKG and muscle-relevant calcium makes it a dual-purpose ingredient for performance nutrition brands.

Bone Health and Calcium Supplementation

With 18–21% elemental calcium content, Ca-AKG serves as a functional calcium source for bone health products. Dosage for calcium supplementation purposes is typically 1–3 g per day, providing 200–600 mg of elemental calcium — well within the tolerable upper intake level of 2,500 mg/day.

Metabolic Health and Functional Foods

Ca-AKG is used in metabolic health formulations targeting mitochondrial support, energy production, and immune function. It can be incorporated into functional foods, beverages, and dietary supplements as a nutrient fortifier.

Regulatory Status and Global Compliance

Ca-AKG benefits from a favorable regulatory landscape across major global markets:

• United States: Alpha-ketoglutarate has received FDA Generally Recognized as Safe (GRAS) status. In January 2026, a Chinese manufacturer's AKG and Ca-AKG products completed the Self-GRAS evaluation under FDA GRAS guidelines, marking the first fermentation-derived AKG product to achieve this certification.
• European Union: Regulated as a food supplement under the European Food Safety Authority (EFSA) framework.
• Canada: Classified as a natural health product by Health Canada.
• Australia: Governed as a complementary medicine by the Therapeutic Goods Administration (TGA).
• India: Regulated as a food supplement under the Food Safety and Standards Authority of India (FSSAI).

Manufacturing Process and Quality Control

The production of high-purity Ca-AKG begins with alpha-ketoglutaric acid as the primary raw material. The AKG is dissolved in purified water, then reacted with a calcium source (such as calcium hydroxide or calcium bicarbonate) under controlled heating and stirring conditions. The resulting solution undergoes filtration to remove impurities, followed by washing, centrifugation, drying, and milling into a fine powder. Final quality testing — including HPLC purity assays, heavy metal screening, and microbial limits — ensures each batch meets pharmaceutical-grade specifications.

Modern manufacturing approaches increasingly employ bio-fermentation methods using food-grade Corynebacterium glutamicum as a carrier organism. This green production route delivers AKG with superior purity, lower impurity profiles, and better environmental sustainability compared to traditional chemical synthesis.

Frequently Asked Questions About Ca-AKG

What is the recommended dosage of Ca-AKG?

Dosage varies by application: 3–6 g/day for athletic performance, 1–3 g/day for calcium supplementation, and 2–4 g/day for anti-aging and mitochondrial support. It is advisable to start at 1–2 g/day and monitor tolerance, adjusting under professional guidance.

How does Ca-AKG compare to liposomal Ca-AKG?

Standard Ca-AKG offers good bioavailability in its powder or capsule form. However, liposomal formulations can significantly enhance absorption by using lipid-based vesicles to protect the compound from degradation and improve cellular uptake. Arshine can supply both bulk Ca-AKG powder and support OEM liposomal capsule production.

Is Ca-AKG suitable for functional foods and beverages?

Yes. Ca-AKG is water-soluble and can be incorporated into a range of food and beverage applications as a nutrient fortifier. Its mild taste profile and good stability make it suitable for tablets, capsules, powders, and liquid formulations.

What certifications does Arshine's Ca-AKG carry?

Our Ca-AKG raw material is available with Halal, Kosher, ISO 9001, and FSSC 22000 certifications. Third-party lab test reports covering purity, heavy metals, and microbial limits accompany every shipment.

Conclusion: Sourcing Ca-AKG for Your Next Formulation

Calcium Alpha-Ketoglutarate stands at the intersection of energy metabolism, anti-aging science, and functional nutrition — three of the most dynamic growth categories in the global supplement market. With strong clinical evidence supporting its role in cellular energy production, mitochondrial health, and biological age modulation, Ca-AKG is rapidly transitioning from a niche research compound to a mainstream formulation ingredient.

For supplement brands, contract manufacturers, and formulation chemists seeking a reliable, high-purity Ca-AKG bulk supplier, Arshine offers the technical expertise, quality certifications, and responsive service that global procurement demands. Reach out today to discuss your project requirements.