Allicin

DescriptionAllicin is one of the major allergens in garlic (Allium sativum L.). It is responsible of the characteristical fiavour of the bulbs.

DescriptionAllicin is a natural product originally isolated from A. sativum that has wide-ranging biological effects including antioxidative, anticancer, antimicrobial, and antifungal activities. It inhibits the cysteine proteases cathepsin B and L, facipain 2, and rhodesain with Ki values of 8.6 and 9.3, 1.04, and 5.31 μM, respectively. It shows antiparasitic activity against P. falciparum (IC50 = 5.2 μM) and T. b. brucei (IC50 = 13.8 μM), the parasites that cause malaria and African sleeping sickness, respectively. Allicin (5-10 μM) dose-dependently inhibits cell adhesion, invasion, and migration in various lung adenocarcinoma cell lines. It also alters the balance of tissue inhibitors of matrix metalloproteinases (TIMPs) and matrix metalloproteinases (MMPs), decreases phosphorylation of Akt, and decreases PI3K/Akt signaling.

HistoryAs the main active substance of garlic, garlic was separated by Cavallito and Bailey in 1944 from crushed garlic. Cavallito firstly clarified the physical properties and chemical structure of the scent of garlic.Fresh garlic does not contain free allicin but only its precursor material alliin. When the garlic undergoes physical mechanical crushing, garlic alliinase is activated and catalyzes the breakdown of alliin into allicin.The reported preparation methods of allicin contain extraction, biosynthesis, and chemical synthesis. Chemical synthesis starts from raw material of diallyldisulfides, m-chloroperoxy benzoic acid to get crude allicin. According to the United States patent report, biosynthesis preparation of allicin comes from natural sources or synthetic, after it is made into a certain concentration of aqueous solution, it is converted into allicin by reaction with alliinase. Extraction of allicin with low boiling nonpolar solvent can acquire pure allicin, but it must be stored at 70°C to prevent from decomposing.

UsesAllicin is naturally formed by the action of the enzyme allicinase on alliin when the tissue of the garlic bulb is disrupted. Allicin shows antibacterial activity.