Coenzyme Q10

Chemical compound

Coenzyme Q10

Names
Preferred IUPAC name

2-[(2E,6E,10E,14E,18E,22E,26E,30E,34E)-3,7,11,15,19,23,27,31,35,39-Decamethyltetraconta-2,6,10,14,18,22,26,30,34,38-decaen-1-yl]-5,6-dimethoxy-3-methylcyclohexa-2,5-diene-1,4-dione

Other names

* In general: Ubiquinone, coenzyme Q, CoQ, vitamin Q
* This form: ubidecarenone,

Q10, CoQ10 /ˌkoʊˌkjuːˈtɛn/

Identifiers

CAS Number

* 303-98-0 Y

3D model (JSmol)

* Interactive image

ChEBI |

* CHEBI:46245 Y

ChEMBL |

* ChEMBL454801 Y

ChemSpider |

* 4445197 Y

ECHA InfoCard | 100.005.590

PubChem CID

* 5281915

UNII |

* EJ27X76M46 Y

CompTox Dashboard (EPA)

* DTXSID6046054

InChI

* InChI=1S/C59H90O4/c1-44(2)24-15-25-45(3)26-16-27-46(4)28-17-29-47(5)30-18-31-48(6)32-19-33-49(7)34-20-35-50(8)36-21-37-51(9)38-22-39-52(10)40-23-41-53(11)42-43-55-54(12)56(60)58(62-13)59(63-14)57(55)61/h24,26,28,30,32,34,36,38,40,42H,15-23,25,27,29,31,33,35,37,39,41,43H2,1-14H3/b45-26+,46-28+,47-30+,48-32+,49-34+,50-36+,51-38+,52-40+,53-42+ Y

Key: ACTIUHUUMQJHFO-UPTCCGCDSA-N Y

* InChI=1/C59H90O4/c1-44(2)24-15-25-45(3)26-16-27-46(4)28-17-29-47(5)30-18-31-48(6)32-19-33-49(7)34-20-35-50(8)36-21-37-51(9)38-22-39-52(10)40-23-41-53(11)42-43-55-54(12)56(60)58(62-13)59(63-14)57(55)61/h24,26,28,30,32,34,36,38,40,42H,15-23,25,27,29,31,33,35,37,39,41,43H2,1-14H3/b45-26+,46-28+,47-30+,48-32+,49-34+,50-36+,51-38+,52-40+,53-42+

Key: ACTIUHUUMQJHFO-UPTCCGCDBK

SMILES

* O=C1/C(=C(\C(=O)C(\OC)=C1\OC)C)C\C=C(/C)CC\C=C(/C)CC\C=C(/C)CC\C=C(/C)CC\C=C(/C)CC\C=C(/C)CC\C=C(/C)CC\C=C(/C)CC\C=C(/C)CC\C=C(/C)C

Properties

Chemical formula

| C59H90O4
Molar mass | 863.365 g·mol−1
Appearance  | yellow or orange solid
Melting point | 48–52 °C (118–126 °F; 321–325 K)

Solubility in water

| insoluble
Pharmacology

ATC code

| C01EB09 (WHO)
Related compounds

Related quinones

| 1,4-Benzoquinone
Plastoquinone
Ubiquinol

Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Y verify (what is YN ?)

Infobox references

Chemical compound

Coenzyme Q10 (CoQ10) also known as ubiquinone, is a naturally occurring biochemical cofactor (coenzyme) and an antioxidant produced by the human body, but it can also be obtained from dietary sources such as meat, fish, and some vegetables. CoQ10 is also found in many organisms including animals and bacteria. CoQ10 plays a central role in mitochondrial oxidative phosphorylation, aiding in the production of adenosine triphosphate (ATP), which is involved in energy transfer within cells. CoQ10 is synthesized endogenously. The structure of CoQ10 consists of a benzoquinone moiety and an isoprenoid side chain, with the "10" referring to the number of isoprenyl chemical subunits in its tail.[1][2][3][4]

## Biological function[edit]

CoQ10 is a lipophilic molecule that is located in all biological membranes of human body and serves as a component for the synthesis of ATP and is a life-sustaining cofactor for the three complexes (complex I, complex II, and complex III) of the electron transport chain in the mitochondria. Specifically, in the Q cycle of Complex III, CoQ10 transports electrons derived from complex I and II to complex III, enabling a continuous supply of electrons that are required for the process of oxidative phosphorylation, leading to the production of ATP.[3][5][6]

## Biochemistry[edit]

CoQ10 is a coenzyme family that is ubiquitous in animals and many Pseudomonadota[7], a group of gram-negative bacteria. The fact that the enzyme is ubiquitous gives the origin of its other name, ubiquinone.[8] In humans, the most common form is Coenzyme Q10, also called CoQ10 (/ˌkoʊkjuːˈtɛn/) or ubiquinone-10.[9][10]

Coenzyme Q10 is a 1,4-benzoquinone, in which Q refers to the quinone chemical group and 10 refers to the number of isoprenyl chemical subunits (shown enclosed in brackets in the diagram) in its tail. In natural ubiquinones, there are from six to ten subunits in the tail.[9]

This family of fat-soluble substances, which resemble vitamins, is present in all respiring eukaryotic cells, primarily in the mitochondria.[11] It is a component of the electron transport chain and participates in aerobic cellular respiration, which generates energy in the form of ATP.[11] Ninety-five percent of the human body's energy is generated this way.[12][13] Organs with the highest energy requirements—such as the heart, liver, and kidney—have the highest CoQ10 concentrations.[14][15][16][17]

There are three redox states of CoQ: fully oxidized (ubiquinone), semiquinone (ubisemiquinone), and fully reduced (ubiquinol). The capacity of this molecule to act as a two-electron carrier (moving between the quinone and quinol form) and a one-electron carrier (moving between the semiquinone and one of these other forms) is central to its role in the electron transport chain due to the iron–sulfur clusters that can only accept one electron at a time, and as a free-radical–scavenging antioxidant.[8][11]

## Deficiency and toxicity[edit]

There are two major pathways of deficiency of CoQ10 in humans: reduced biosynthesis, and increased use by the body. Biosynthesis is the major source of CoQ10. Biosynthesis requires at least 12 genes, and mutations in many of them cause CoQ deficiency. CoQ10 levels also may be affected by other genetic defects (such as mutations of mitochondrial DNA, ETFDH, APTX, FXN, and BRAF, genes that are not directly related to the CoQ10 biosynthetic process). Some of these, such as mutations in COQ6, can lead to serious diseases such as steroid-resistant nephrotic syndrome with sensorineural deafness.[medical citation needed]

Some adverse effects, largely gastrointestinal, are reported with very high intakes. The observed safe level (OSL) risk assessment method indicated that the evidence of safety is strong at intakes up to 1200 mg/day, and this level is identified as the OSL.[18][6]

### Assessment[edit]

Although CoQ10 may be measured in blood plasma, these measurements reflect dietary intake rather than tissue status. Currently, most clinical centers measure CoQ10 levels in cultured skin fibroblasts, muscle biopsies, and blood mononuclear cells.[19] Culture fibroblasts can be used also to evaluate the rate of endogenous CoQ10 biosynthesis, by measuring the uptake of 14C-labelled p-hydroxybenzoate.[20]

### Statins[edit]

While statins may reduce coenzyme Q10 in the blood it is unclear if they reduce coenzyme Q10 in muscle.[21] Evidence does not support that supplementation improves side effects from statins.[21] However, a more recent metanalysis conducted in China, one of the world's largest producers of this supplement, concluded that, "CoQ10 supplementation ameliorated SAMSs [statin‐associated muscle symptoms], implying that CoQ10 supplementation might be a complementary approach to ameliorate statin‐induced myopathy."[22]

## Dietary supplement[edit]

Although neither a prescription drug nor an essential nutrient, CoQ10 is commonly used as a dietary supplement with the intent to prevent or improve disease conditions, such as cardiovascular disorders.[8][11] A variety of companies have been trying to sell CoQ10 as supplement, although there is no solid evidence of beneficiary effects of CoQ10 supplementation.[23] CoQ10 is naturally produced by the body and plays a crucial role in cell growth and protection.[4] Despite its significant role in the body, as a supplementation, it has not received approval from the United States Food and Drug Administration (FDA) for the treatment of any specific medical condition.[11] Nevertheless, CoQ10 is widely available as an over-the-counter dietary supplement and is frequently recommended by healthcare professionals, including both primary care clinicians and specialists, where these specialists suppose that the supplementation may have its potential health benefits, which include supporting the skin, brain, and lungs, as well as offering protection against chronic diseases like cancer or diabetes; still, definitive scientific evidence supporting these claims is currently lacking.[11] Despite the lack of FDA approval, CoQ10 continues to be used in various forms, including in some cosmetics, even given the lack of proven benefits.[11]

### Regulation and composition[edit]

CoQ10 is not approved by the U.S. Food and Drug Administration (FDA) for the treatment of any medical condition.[24][25][26][27] However, it is sold as a dietary supplement in the name of UbiQ 300 & UbiQ 100, not subject to the same regulations as medicinal drugs, and is an ingredient in some cosmetics.[28][29] The manufacture of CoQ10 is not regulated, and different batches and brands may vary significantly:[26] a 2004 laboratory analysis by ConsumerLab.com of CoQ10 supplements on sale in the US found that some did not contain the quantity identified on the product label. Amounts ranged from "no detectable CoQ10", through 75% of stated dose, up to a 75% excess.[30][31]

Generally, CoQ10 is well tolerated. The most common side effects are gastrointestinal symptoms (nausea, vomiting, appetite suppression, and abdominal pain), rashes, and headaches.[32]

### Heart disease[edit]

A 2014 Cochrane review found insufficient evidence to make a conclusion about its use for the prevention of heart disease.[33] A 2016 Cochrane review concluded that CoQ10 had no effect on blood pressure.[34] A 2021 Cochrane review found "no convincing evidence to support or refute" the use of CoQ10 for the treatment of heart failure.[35]

In a 2017 meta-analysis of people with heart failure 30–100 mg/d of CoQ10 resulted in 31% lower mortality. Exercise capacity was also increased. No significant difference was found in the endpoints of left heart ejection fraction and New York Heart Association (NYHA) classification.[36]

In a 2023 meta-analysis of older people ubiquinone was compared with ubiquinol. The results demonstrate a beneficial cardiovascular effect of ubiquinone. This could not be confirmed for ubiquinol.[37]

### Migraine headaches[edit]

The Canadian Headache Society guideline for migraine prophylaxis recommends, based on low-quality evidence, that 300 mg of CoQ10 be offered as a choice for prophylaxis.[38]

### Statin myopathy[edit]

Although CoQ10 has been used to treat purported muscle-related side effects of statin medications, a 2015 meta-analysis of randomized controlled trials found that CoQ10 had no effect on statin myopathy.[39] A 2018 meta-analysis concluded that there was preliminary evidence for oral CoQ10 reducing statin-associated muscle symptoms, including muscle pain, muscle weakness, muscle cramps and muscle tiredness.[22]

### Cancer[edit]

As of 2014[update] no large clinical trials of CoQ10 in cancer treatment had been conducted.[26] The US's National Cancer Institute identified issues with the few, small studies that had been carried out, stating, "the way the studies were done and the amount of information reported made it unclear if benefits were caused by the CoQ10 or by something else".[26] The American Cancer Society concluded, "CoQ10 may reduce the effectiveness of chemo and radiation therapy, so most oncologists would recommend avoiding it during cancer treatment."[40]

### Dental disease[edit]

A 1995 review study found that there is no clinical benefit to the use of CoQ10 in the treatment of periodontal disease.[41]

### Chronic kidney disease[edit]

A review of the effects of CoQ10 supplementation in people with CKD was proposed in 2019.[42]

### Additional uses[edit]

Coenzyme Q10 has also been utilized as an active ingredient in cosmeceuticals and as an inactive ingredient in sunscreen formulations. When applied topically in skincare products it demonstrates some ability to reduce oxidative stress in the skin,[43] delay signs of intrinsic skin aging, reverse signs of extrinsic skin aging,[44][45] assist in fading dyspigmentation,[46][47] increase stability of certain sunscreen actives,[48] increase the SPF of sunscreens,[49] and afford some infrared protection to sunscreens.[50][51] Much of the research on the skin benefits of ubiquinone show that it works synergistically with other topical antioxidants to improve the skin and cosmetic formulations.

CoQ10 has also been used in in vitro fertilization and oocyte cryopreservation as a pretreatment to improve ovarian response and embryo quality in women with decreased ovarian reserve.[52]

## Interactions[edit]

Coenzyme Q10 has potential to inhibit the effects of theophylline as well as the anticoagulant warfarin; coenzyme Q10 may interfere with warfarin's actions by interacting with cytochrome p450 enzymes thereby reducing the INR, a measure of blood clotting.[53] The structure of coenzyme Q10 is very similar to that of vitamin K, which competes with and counteracts warfarin's anticoagulation effects. Coenzyme Q10 should be avoided in patients currently taking warfarin due to the increased risk of clotting.[32]

## Chemical properties[edit]

The oxidized structure of CoQ10 is shown below. The various kinds of coenzyme Q may be distinguished by the number of isoprenoid subunits in their side-chains. The most common coenzyme Q in human mitochondria is CoQ10.[10] Q refers to the quinone head and "10" refers to the number of isoprene repeats in the tail.[1] The molecule below has three isoprenoid units and would be called Q3.

In its pure state, it is an orange-coloured lipophile powder, and has no taste nor odor.[8]

## Biosynthesis[edit]

Biosynthesis occurs in most human tissue. There are three major steps:

1. Creation of the benzoquinone structure (using phenylalanine or tyrosine, via 4-hydroxybenzoate)
2. Creation of the isoprene side chain (using acetyl-CoA)
3. The joining or condensation of the above two structures

The initial two reactions occur in mitochondria, the endoplasmic reticulum, and peroxisomes, indicating multiple sites of synthesis in animal cells.[54]

An important enzyme in this pathway is HMG-CoA reductase, usually a target for intervention in cardiovascular complications. The "statin" family of cholesterol-reducing medications inhibits HMG-CoA reductase. One possible side effect of statins is decreased production of CoQ10, which may be connected to the development of myopathy and rhabdomyolysis. However, the role statins play in CoQ deficiency is controversial. Although statins reduce blood levels of CoQ, studies on the effects of muscle levels of CoQ are yet to come. CoQ supplementation also does not reduce side effects of statin medications.[19][21]

Genes involved include PDSS1, PDSS2, COQ2, and ADCK3 (COQ8, CABC1).[55]

Organisms other than humans produce the benzoquinone and isoprene structures from somewhat different source chemicals. For example, the bacteria E. coli produces the former from chorismate and the latter from a non-mevalonate source. The common yeast S. cerevisiae, however, derives the former from either chorismate or tyrosine and the latter from mevalonate. Most organisms share the common 4-hydroxybenzoate intermediate, yet again uses different steps to arrive at the "Q" structure.[56]

## Absorption and metabolism[edit]

### Absorption[edit]

CoQ10 is a crystalline powder insoluble in water. Absorption follows the same process as that of lipids; the uptake mechanism appears to be similar to that of vitamin E, another lipid-soluble nutrient.[17] This process in the human body involves secretion into the small intestine of pancreatic enzymes and bile, which facilitates emulsification and micelle formation required for absorption of lipophilic substances.[57] Food intake (and the presence of lipids) stimulates bodily biliary excretion of bile acids and greatly enhances absorption of CoQ10. Exogenous CoQ10 is absorbed from the small intestine and is best absorbed if taken with a meal. Serum concentration of CoQ10 in fed condition is higher than in fasting conditions.[58][59]

### Metabolism[edit]

Data on the metabolism of CoQ10 in animals and humans are limited.[17] A study with 14C-labeled CoQ10 in rats showed most of the radioactivity in the liver two hours after oral administration when the peak plasma radioactivity was observed, but CoQ9 (with only 9 isoprenyl units) is the predominant form of coenzyme Q in rats.[60] It appears that CoQ10 is metabolised in all tissues, while a major route for its elimination is biliary and fecal excretion. After the withdrawal of CoQ10 supplementation, the levels return to normal within a few days, irrespective of the type of formulation used.[61]

## Pharmacokinetics[edit]

Some reports have been published on the pharmacokinetics of CoQ10. The plasma peak can be observed 2–6 hours after oral administration, depending mainly on the design of the study. In some studies, a second plasma peak also was observed at approximately 24 hours after administration, probably due to both enterohepatic recycling and redistribution from the liver to circulation.[57] Deuterium-labeled crystalline CoQ10 was used to investigate pharmacokinetics in humans to determine an elimination half-time of 33 hours.[62]

### Improving the bioavailability of CoQ10[edit]

The importance of how drugs are formulated for bioavailability is well known. In order to find a principle to boost the bioavailability of CoQ10 after oral administration, several new approaches have been taken; different formulations and forms have been developed and tested on animals and humans.[17]

#### Reduction of particle size[edit]

Nanoparticles have been explored as a delivery system for various drugs, such as improving the oral bioavailability of drugs with poor absorption characteristics.[63] However, this has not proved successful with CoQ10, although reports have differed widely.[64][65] The use of aqueous suspension of finely powdered CoQ10 in pure water also reveals only a minor effect.[61]

#### Soft-gel capsules with CoQ10 in oil suspension[edit]

A successful approach is to use the emulsion system to facilitate absorption from the gastrointestinal tract and to improve bioavailability. Emulsions of soybean oil (lipid microspheres) could be stabilised very effectively by lecithin and were used in the preparation of softgel capsules. In one of the first such attempts, Ozawa et al. performed a pharmacokinetic study on beagles in which the emulsion of CoQ10 in soybean oil was investigated; about twice the plasma CoQ10 level than that of the control tablet preparation was determined during administration of a lipid microsphere.[61] Although an almost negligible improvement of bioavailability was observed by Kommuru et al. with oil-based softgel capsules in a later study on dogs,[66] the significantly increased bioavailability of CoQ10 was confirmed for several oil-based formulations in most other studies.[67]

#### Novel forms of CoQ10 with increased water-solubility[edit]

Facilitating drug absorption by increasing its solubility in water is a common pharmaceutical strategy and also has been shown to be successful for CoQ10. Various approaches have been developed to achieve this goal, with many of them producing significantly better results over oil-based softgel capsules in spite of the many attempts to optimize their composition.[17] Examples of such approaches are use of the aqueous dispersion of solid CoQ10 with the polymer tyloxapol,[68] formulations based on various solubilising agents, such as hydrogenated lecithin,[69] and complexation with cyclodextrins; among the latter, the complex with β-cyclodextrin has been found to have highly increased bioavailability[70][71] and also is used in pharmaceutical and food industries for CoQ10-fortification.[17]

## Dietary concentrations[edit]

Detailed reviews on occurrence of CoQ10 and dietary intake were published in 2010.[72] Besides the endogenous synthesis within organisms, CoQ10 also is supplied to the organism by various foods. Despite the scientific community's great interest in this compound, however, a very limited number of studies have been performed to determine the contents of CoQ10 in dietary components.[6] The first reports on this aspect were published in 1959, but the sensitivity and selectivity of the analytical methods at that time did not allow reliable analyses, especially for products with low concentrations.[72] Since then, developments in analytical chemistry have enabled a more reliable determination of CoQ10 concentrations in various foods:[72]

CoQ10 levels in selected foods[72] Food | CoQ10 concentration (mg/kg)

|

Oils | soybean | 54–280
olive | 40–160
grapeseed | 64–73
sunflower | 4–15
canola | 64–73
Beef | heart | 113
liver | 39–50
muscle | 26–40
Pork | heart | 12–128
liver | 23–54
muscle | 14–45
Chicken | breast | 8–17
thigh  | 24–25
wing  | 11
Fish | sardine | 5–64
mackerel: |
– red flesh | 43–67
– white flesh | 11–16
salmon | 4–8
tuna | 5
Nuts | peanut | 27
walnut | 19
sesame seed | 18–23
pistachio | 20
hazelnut | 17
almond | 5–14
Vegetables | parsley | 8–26
broccoli | 6–9
cauliflower | 2–7
spinach | up to 10
Chinese cabbage | 2–5
Fruit | avocado | 10
blackcurrant | 3
grape | 6–7
strawberry | 1
orange | 1–2
grapefruit | 1
apple | 1
banana | 1

Vegetable oils are the richest sources of dietary CoQ10; Meat and fish also are quite rich in CoQ10 levels over 50 mg/kg may be found in beef, pork, and chicken heart and liver. Dairy products are much poorer sources of CoQ10 than animal tissues. Among vegetables, parsley and perilla are the richest CoQ10 sources, but significant differences in their CoQ10 levels may be found in the literature. Broccoli, grapes, and cauliflower are modest sources of CoQ10. Most fruit and berries represent a poor to very poor source of CoQ10, with the exception of avocados, which have a relatively high CoQ10 content.[72][72]

### Intake[edit]

In the developed world, the estimated daily intake of CoQ10 has been determined at 3–6 mg per day, derived primarily from meat.[72][72]

South Koreans have an estimated average daily CoQ (Q9 \+ Q10) intake of 11.6 mg/d, derived primarily from kimchi.[73]

### Effect of heat and processing[edit]

Cooking by frying reduces CoQ10 content by 14–32%.[74]

## History[edit]

In 1950, a small amount of CoQ10 was isolated from the lining of a horse's gut, a compound initially called substance SA, but later deemed to be quinone found in many animal tissues.[75] In 1957, the same compound was isolated from mitochondrial membranes of beef heart, with research showing that it transported electrons within mitochondria. It was called Q-275 as a quinone.[75][76] The Q-275/substance SA was later renamed ubiquinone as it was a ubiquitous quinone found in all animal tissues.[75] In 1958, its full chemical structure was reported.[75][77] Ubiquinone was later called either mitoquinone or coenzyme Q due to its participation to the mitochondrial electron transport chain.[75] In 1966, a study reported that reduced CoQ6 was an effective antioxidant in cells.[78]

## See also[edit]

* Idebenone – synthetic analog with reduced oxidant generating properties
* Mitoquinone mesylate – synthetic analog with improved mitochondrial permeability

## References[edit]

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## External links[edit]

* "List of USP Verified CoQ10 Ingredients". U.S. Pharmacopeial Convention. Archived from the original on 9 February 2009.
* Bonakdar RA, Guarneri E (15 September 2005). "Coenzyme Q10". American Family Physician. 72 (6): 1065–1070. PMID 16190504. Archived from the original on 24 July 2008. Retrieved 13 November 2008.

* v
* t
* e

Metabolism: Citric acid cycle enzymes

Cycle|

* Citrate synthase
* Aconitase
* Isocitrate dehydrogenase
* Oxoglutarate dehydrogenase
* Succinyl CoA synthetase

* Succinate dehydrogenase (SDHA)
* Fumarase
* Malate dehydrogenase and ETC

Anaplerotic|

| to acetyl-CoA|

* Pyruvate dehydrogenase complex (E1, E2, E3)

* (regulated by Pyruvate dehydrogenase kinase and Pyruvate dehydrogenase phosphatase)

|

to α-ketoglutaric acid|

* Glutamate dehydrogenase

to succinyl-CoA|

* Methylmalonyl-CoA mutase

to oxaloacetic acid|

* Pyruvate carboxylase
* Aspartate transaminase

Mitochondrial
electron transport chain/
oxidative phosphorylation|

| Primary|

* Complex I/NADH dehydrogenase
* Complex II/Succinate dehydrogenase
* Coenzyme Q10 (CoQ10)
* Complex III/Coenzyme Q - cytochrome c reductase
* Cytochrome c
* Complex IV/Cytochrome c oxidase

* Coenzyme Q10 synthesis: COQ2
* COQ3
* COQ4
* COQ5
* COQ6
* COQ7
* COQ9
* COQ10A
* COQ10B
* PDSS1
* PDSS2

|

Other|

* Alternative oxidase
* Electron-transferring-flavoprotein dehydrogenase

* v
* t
* e

Enzyme cofactors

Active forms|

| vitamins|

* TPP / ThDP (B1)
* FMN, FAD (B2)
* NAD+, NADH, NADP+, NADPH (B3)
* Coenzyme A (B5)
* PLP / P5P (B6)
* Biotin (B7)
* THFA / H4FA, DHFA / H2FA, MTHF (B9)
* AdoCbl, MeCbl (B12)
* Ascorbic acid (C)
* Phylloquinone (K1), Menaquinone (K2)
* Coenzyme F420

|

non-vitamins|

* ATP
* CTP
* SAMe
* PAPS
* GSH
* Coenzyme B
* Cofactor F430
* Coenzyme M
* Coenzyme Q
* Heme / Haem (A, B, C, O)
* Lipoic Acid
* Methanofuran
* Molybdopterin
* Mycofactocin
* PQQ
* THB / BH4
* THMPT / H4MPT

metal ions|

* Ca2+
* Cu2+
* Fe2+, Fe3+
* Mg2+
* Mn2+
* Mo
* Ni2+
* Zn2+

Base forms|

* vitamins: see vitamins

* v
* t
* e

Antioxidants

Food antioxidants|

* 6-Hydroxymelatonin
* Acetyl-L-carnitine (ALCAR)
* Alpha-lipoic acid (ALA)
* Ascorbic acid (vitamin C)
* Carotenoids (vitamin A)
* Curcumin
* Edaravone
* Polyphenols
* Glutathione
* Hydroxytyrosol
* L-carnitine
* Ladostigil
* Melatonin
* Mofegiline
* N-Acetylcysteine (NAC)
* N-Acetylserotonin (NAS)
* Oleocanthal
* Oleuropein
* Rasagiline
* Resveratrol
* Selegiline
* Selenium
* Tocopherols (vitamin E)
* Tocotrienols (vitamin E)
* Tyrosol
* Ubiquinone (coenzyme Q)
* Uric acid

Fuel antioxidants|

* Butylated hydroxyanisole
* Butylated hydroxytoluene
* 2,6-Di-tert-butylphenol
* 1,2-Diaminopropane
* 2,4-Dimethyl-6-tert-butylphenol
* Ethylenediamine

Measurements|

* Folin method
* ORAC
* TEAC
* FRAP

*[CID]: Compound ID
*[EPA]: U.S. Environmental Protection Agency
*[v]: View this template
*[t]: Discuss this template
*[e]: Edit this template