What is alliin?

Alliin, an ingredient with CAS number 556-27-4, is not so popular with the public. Alliin seems to only appear in scientific literature. Even when you type alliin in the search engine, Google will show most everything pointing to allicin.

In fact, alliin is not allicin since they have different structures and CAS numbers. However, they are connected, and both are related to garlic. Yeah, that is right, just the odorous garlic in the kitchen. When fresh garlic is chopped or crushed, an enzyme called alliinase then converts alliin into allicin.

Alliin is the most abundant organosulfur compound in the whole garlic bulbs. Allicin’s IUPAC name is (2R)-2-amino-3-[(S)-prop-2-enylsulfinyl]propanoic acid, with other names as 2-propene-1-sulfinothioic acid S-2-propenyl ester, thio-2-propene-1- sulfinic acid S-allyl ester, diellyl disulfide-oxide, diallyl thiosulfinate, S-Allyl-L-cysteine sulfoxide, etc.

In most scientific documents, alliin is often named by researchers as S-allyl-cysteine sulfoxide (ACSO for short), S-allyl cysteine sulphoxide, or S-allylcysteine sulfoxide. IdoBio is among the first manufacturers of bulk alliin powder in China, even all over the world. The name S-allyl-cysteine sulfoxide is too hard to be pronounced or memorized. Therefore, alliin is the ideal name for the commercial name, and we will use alliin in the rest of the article.

Alliin VS allicin comparisons

According to Wikipedia, alliin, a derivative of the amino acid cysteine, is a sulfoxide that is a natural constituent of fresh garlic. Well, allicin doesn’t exist abundantly in fresh garlic. This is the first difference.

As mentioned before, when fresh garlic is chopped or crushed, an enzyme called alliinase then converts alliin into allicin. This is their connection. Alliin is the precursor of allicin. Alliinase is extremely abundant in garlic tissue consisting of at least 10% of the total clove protein.

Let’s talk about stability.

Alliin and the enzyme alliinase are quite heat stable. Alliin and alliinase are also stable when dry and therefore dried powders can potentially preserve the biological activity of garlic.

However, normal allicin is not stable. Allicin molecules have a very short half-life, as they react with many surrounding proteins. Allicin is further metabolized to vinyldithiines. Allicin decomposes into other sulfur-containing molecules (thiosulfonates and disulfides). This breakdown occurs within hours at room temperature and within minutes during cooking. In this sense, natural allicin in the chopped or crushed garlic is not stable, and could not be utilized as a supplement for bulk usage. Therefore, stabilized allicin is a must. You will find that most nutritional facts label of supplements containing allicin says that their allicin is stabilized allicin. Non-stabilized allicin is useless.

About odor and popularity

Alliin is odorless and less known to the consumers.

Natural allicin has a very distinct odor and is responsible for the aroma of fresh garlic.

Most allicin supplements have been deodorized, and no smell can be found.

Many medicinal effects of garlic products are probably, or at least partly, attributable to alliin, whereas the extent that which alliin contributes to the beneficial function of garlic is not quite clear. Systematic studying of the nutraceutical or medicinal effect of alliin is lacking.

Main components of garlic

Alliin is part of garlic, and what else ingredients are in garlic?
 

Garlic is a species in the onion genus, Allium, with the Latin name Allium sativum. The quality of fresh garlic and garlic products is usually related to their alliin content and allicin release potential.

Garlic, native to China, has been used both as a food flavoring and as a traditional medicine for more than 5000 years, and now 80% of the world’s supply of garlic is from China.

Various factors are involved and affect the chemical composition of garlic, such as genotype, growing conditions, irrigation, fertilization, etc. In this sense, we will not list the exact percentages of compounds in the garlic, just a brief introduction.

Garlic is believed to contain at least 33 sulfur compounds, several enzymes, 17 amino acids, and minerals such as selenium. It contains a higher concentration of sulfur compounds than any other Allium species. The sulfur compounds are responsible both for garlic’s pungent odor and for many of its medicinal effects. Dried, powdered garlic contains approximately 1% alliin (S-allyl cysteine sulfoxide). One of the most biologically active compounds, allicin (diallyl thiosulfinate or diallyl disulfide), does not exist in garlic until it is crushed or cut; injury to the garlic bulb activates the enzyme alliinase, which metabolizes alliin to allicin.

The content of alliin in garlic can vary considerably due to garlic variety but also production practices.

Alliin benefits

Garlic is reported to have cancer prevention, antimicrobial, antibiotic, antihypertensive, hypoglycemic, and cholesterol-lowering properties, among others.

Research also shows that garlic can reduce blood cholesterol and has proven anti-cancer effects. These beneficial effects may be due in part to garlic’s unusual concentration of sulfur-containing compounds, especially alliin and allicin.

An extensive literature review discloses the nutraceutical and medicinal potential of alliin in several aspects. For example, alliin decreased fasting glucose levels and increased insulin levels to the same extent as did glibenclamide, glyclazide, or insulin in diabetic rats. Weeks’ administration of alliin modified the redox environment by decreasing reactive substances in organs and increasing the activities of catalase and superoxide dismutase in nicotine-fed rats. Another study showed that alliin markedly depressed the increase of plasma and liver cholesterol levels in rats fed a hypercholesterolemic diet containing 10% hydrogenated coconut oil, 1% cholesterol, and 0.2% cholic acid. Alliin was also found to possess anti-inflammatory activities for bowel diseases. These symptoms like diabetes, high radicals, hypercholesterolemia, and inflammation are all associated with obesity and/or metabolic diseases.

The research on alliin currently focuses on preventing nicotine-induced peroxidative damage and antioxidant, antidiabetic conditions, antibiotic, antiatherogenic, anticancer effects and immunomodulatory activity, and antiplatelet aggregation activity.

Alliin and Myocardial Infarction

Myocardial infarction (MI) is considered to be characterized by necrotic cell death because of the breakdown of cellular energy metabolism. Mitochondria are the location of ATP synthesis for energy production and the electron transport chain.

Myocardial infarction was induced by subcutaneous injection of isoproterenol (150 mg/kg) once a day for 2 days. Alliin (40 and 80 mg/kg) was given as pretreatment orally daily for a period of 35 days using an intragastric tube. Alliin pretreatment significantly lowered thiobarbituric acid reactive substances (TBARS) and increased the activities of mitochondrial superoxide dismutase (SOD), catalase, and glutathione peroxidase (GPx), glutathione S-transferase (GST), and the concentration of reduced glutathione (GSH) in myocardial infarcted rats. Alliin pretreatment also increased significantly the levels of mitochondrial phospholipids and decreased the levels of mitochondrial cholesterol, free fatty acids (FFAs), triglycerides (TGs), calcium, and the activity of xanthine oxidase (XOD) in the heart.

Alliin and Anti-inflammatory

Alliin has been known to have anti-oxidative and anti-inflammatory effects. Alliin has been reported to attenuate RANKL-induced osteoclastogenesis by scavenging reactive oxygen species (ROS) production.

Alliin has been reported to inhibit inflammatory cytokines production in RAW264.7 cells by inhibiting NF-κB activation. Furthermore, alliin was found to prevent LPS-induced inflammation in 3T3-L1 adipocytes.

In addition, alliin was found to attenuate dextran sodium sulfate (DSS)-induced ulcerative colitis in vivo.

The mechanism of action of alliin can be summarized as below:

• Activity in T-cell lymphocytes by inhibition of SDF1a-chemokine-induced chemotaxis
• Inhibition of transendothelial migration of neutrophils
• Enhancement of the phosphorylation of ERK1/2 kinase (via p21ras protein thioallylation)
• Inhibition of TNFa-dependent pro-inflammatory cytokines release
• Inhibition of phosphatase-activity (directly related to ERK1/2 phosphorylation)
• Suppression of reactive nitrogen species release

Alliin and alcohol metabolism

Alliin, for the first time, has been shown to have the property of suppressing elevation in plasma ethanol concentration by accelerating ethanol metabolism and preventing ethanol absorption from the gut in rats.

Two mechanisms can be considered for the suppressive effect of alliin on the elevation of ethanol concentration in plasma:
(1) Suppression of ethanol absorption from the gut;
(2) Promotion of ethanol metabolism in the liver.

For more detailed experiment data and information, please read this literature: S-Allyl-L-cysteine sulfoxide, a garlic odor precursor, suppresses elevation in blood ethanol concentration by accelerating ethanol metabolism and preventing ethanol absorption from the gut.

Supplements containing alliin

At present, there are no sole alliin brands or dietary supplements on the markets. Alliin is more likely to be formulated with other garlic active components, such as allicin, thiosulfinates, Gamma-Glutamylcysteines, etc. most of that deodorized Garlic (bulb) standardized to 2.5% of alliin. Be aware that, our alliin ingredient in powder is 98% minimum!

In addition, many drugs or medicines are beginning to use alliin in their formulas too to fight against myocardial infarction, acute lung injury, alcohol, and more.

 

Alliin side effects

Alliin is new to the dietary supplement market and has not been reported to have any negative effects yet.

Alliin dosage

There are no ready alliin supplements for the time being, and the daily dose of alliin is not available.

You may check the allicin dosage for reference.

Some brands mention that one capsule per day with allicin (180mg/day);

Some mention taking two capsules a day, one capsule containing 30mg of 2.5% alliin, which is 60mg alliin per day. If alliin is 98%, the dosage will absolutely be less. If you have any questions regarding the dosage of alliin, please consult our chemist scientists by dropping an e-mail on our contact page.