Allicin (Organosulfur Thiosulfinate · Antimicrobial · Cardiovascular · Garlic Active)
| Compound | Allicin (Diallyl Thiosulfinate) |
| Chemical class | Organosulfur — Thiosulfinate (Diallyl thiosulfinate) |
| CAS | 539-86-6 |
| Primary source | Allium sativum (garlic bulb) — formed enzymatically from alliin by alliinase upon tissue disruption |
| Key applications | Antimicrobial, cardiovascular, blood pressure, cholesterol, antifungal |
| Claim strength | Moderate |
| Typical form | Fresh garlic; allicin-standardised garlic extract; garlic oil (allicin conversion products) |
| Buy from Herbuno |
Name origin: From Allium (the garlic genus). Allicin is the primary bioactive thiosulfinate of fresh garlic, formed immediately when garlic cells are damaged: alliin + alliinase enzyme → allicin + pyruvate + NH3. In intact, undamaged garlic, alliin (the stable precursor) and alliinase are stored in separate cellular compartments — crushing or chopping garlic brings them together. Traditional use: Garlic (Allium sativum, Lahsun in Hindi, Rasona in Ayurveda) has been used medicinally for over 5,000 years — referenced in the Ebers Papyrus (Egypt, 1550 BCE) and Indian Charaka Samhita, and praised by Hippocrates for wound healing and respiratory conditions. Traditional garlic applications span every human culture, covering cardiovascular, antimicrobial, digestive, respiratory, immune, and anticancer indications. Research trajectory: Garlic is one of the most clinically studied botanical ingredients globally, with >5,000 publications and multiple systematic reviews. However, the evidence quality is complicated by the instability of allicin (which rapidly degrades to diallyl disulfide, diallyl trisulfide, ajoene, and other organosulfur compounds) — making standardisation and clinical comparison difficult. The most replicated clinical effects are modest blood pressure reduction and cholesterol lowering. Commercial source: Garlic Extract Powder and Dehydrated Garlic Powder from Herbuno. See sourcing options below.
Evidence for Allicin Applications
Blood pressure reduction: A systematic review and meta-analysis (Ried et al. 2016, 17 RCTs) of garlic preparations found a significant mean reduction of 5.1 mmHg systolic and 2.5 mmHg diastolic blood pressure in hypertensive patients. Allicin inhibits ACE (angiotensin-converting enzyme) and produces H2S (via allicin → polysulfide → H2S pathway) which promotes vasodilation. Claim strength: Moderate.
Cholesterol modulation: Meta-analysis of RCTs (Ried et al. 2013) found garlic preparations modestly but significantly reduce total cholesterol (by approximately 0.4 mmol/L, ~8%) and LDL-C, with no significant effect on HDL-C or triglycerides. Effect sizes are smaller than pharmaceutical statins but clinically meaningful for mild dyslipidaemia management. Claim strength: Moderate.
Antimicrobial: Allicin has broad-spectrum antimicrobial activity against bacteria (S. aureus including MRSA, E. coli, H. pylori), fungi (Candida albicans), and viruses (influenza, rhinovirus, herpes simplex). Mechanism: allicin reacts with thiol groups (cysteine residues) in microbial enzymes via thiol-disulfide exchange, irreversibly inhibiting essential metabolic enzymes. Claim strength: Moderate.
Antiplatelet and anticoagulant: Allicin inhibits platelet aggregation by blocking thromboxane A2 synthesis and enhancing prostacyclin. Relevant for cardiovascular risk management. Standard advisory for anticoagulant interactions applies. Claim strength: Moderate.
Browse Standardised Extract Powders →
Dosage & Formulator Specification
Human RCT dose range: preparations providing 600–2,400 mg/day garlic extract, standardised to allicin yield (1,800–7,200 µg allicin/day). The Ried blood pressure meta-analysis used preparations providing 188–2,400 mg/day garlic extract. Allicin is inherently unstable — it degrades rapidly in aqueous environments, at elevated temperatures, and upon exposure to air. “Allicin yield” (the amount of allicin potentially generated upon tablet/capsule dissolution) is a more meaningful specification than “allicin content” (which may be zero in aged or processed preparations). Enteric-coated garlic tablets are preferred for maximum allicin delivery to the small intestine, avoiding gastric acid degradation.
Herbuno’s Garlic Extract Powder provides alliin (the stable allicin precursor) alongside alliinase and other organosulfur compounds. Specify alliin content (by HPLC) and allicin yield (by the AOAC method) on CoA. Fresh garlic equivalent claims should specify the allicin yield generated upon reconstitution/digestion.
Frequently Asked Questions — Allicin
Why doesn’t garlic smell until you crush it?
In intact garlic, alliin (the stable, odourless precursor) and alliinase (the enzyme that converts alliin to allicin) are stored in separate cellular compartments — alliin in vacuoles, alliinase in the cytoplasm. When garlic cells are disrupted (crushing, chopping, chewing), the compartments mix, alliinase converts alliin to allicin (pungent, characteristic garlic smell) within seconds, and allicin then degrades to other volatile organosulfur compounds (diallyl disulfide, diallyl trisulfide) contributing to the complex garlic aroma. Whole, undamaged garlic cloves have essentially no allicin — it is generated de novo upon cell damage.
Is aged garlic extract (AGE) the same as fresh garlic?
No — fundamentally different compositions. Aged garlic extract (produced by prolonged aging of garlic in aqueous ethanol) loses almost all allicin (degraded during aging) and instead accumulates water-soluble organosulfur compounds: S-allylcysteine (SAC), S-allylmercaptocysteine (SAMC), alliin residues, and fructooligosaccharides. SAC is the primary bioactive in AGE — it is stable, odourless, and has excellent oral bioavailability (unlike allicin). AGE has its own evidence base (cardiovascular, antioxidant, neuroprotective) that is distinct from fresh garlic/allicin evidence. They are not interchangeable for formulation purposes.
Does cooking destroy allicin?
Yes. Allicin is heat-labile — it degrades at temperatures above 60°C within minutes. Raw garlic generates allicin; cooked garlic has negligible allicin (it converts to less pungent polysulfides during cooking). However, cooked garlic retains other organosulfur compounds (diallyl disulfide, diallyl trisulfide) with their own antimicrobial, cardiovascular, and antiproliferative properties. The health benefits of cooked garlic are real but mediated by different compounds than raw garlic’s allicin. Crushing garlic and allowing 10 minutes at room temperature before cooking “locks in” some allicin conversion before heat inactivates alliinase.
Can garlic supplements cause drug interactions?
Garlic supplements (especially high-allicin preparations) have documented interactions: (1) Anticoagulants (warfarin, heparin, aspirin) — additive antiplatelet effects increase bleeding risk; (2) Saquinavir (HIV protease inhibitor) — garlic extract reduces saquinavir plasma levels by 50% via CYP3A4 induction; (3) Antihypertensives — additive blood pressure reduction. Standard advisory language for these interactions should be included on garlic supplement labels. The interactions are significant and well-documented.
Related compounds: Alliin, S-Allylcysteine, Diindolylmethane, Sulforaphane
Claim-strength scale – High = multiple human RCTs; Moderate = limited trials or strong preclinical convergence; Emerging = early-stage lab or animal data.
← HerbIQ Compound Index · HerbIQ P02: Extraction · HerbIQ P03: Delivery