Allicin antifungal activity

A number of studies have focused on identifying the active antimicrobial principles in fresh garlic extract. Allicin has been identified as the active agent in garlic extracts. The antifungal activity of allicin has been shown to depend on the sulfhydryl moiety because activity is destroyed by thiols such as L-cysteine, glutathione, and mercaptoethanol. Ajoene, a compound found in oil-macerated garlic, has also been shown to have antimicrobial activity (Ali et al., 2000). 

Alliaceous plants release characteristic volatile compounds. The most well-known compound is the allylthio-sulfinate allicin (169), which is produced from alliin (170) by alliinase and exhibits strong antibacterial and antifungal activities. For this reason, alliaceous plants are used as companion plants of tomato, cucumber,... 

Allicin not only shows antibacterial activity, but also antifungal [63], antiprotozoal [87], anti-parasitic [88] and antiviral activities [89]. It has recently been shown to inhibit the ability of Entamoeba histolytica trophozoites to destroy monolayers of baby hamster kidney cells [90]. Cysteine proteinases, an imporatant contributor to amebic virulence, as well as alcohol dehydrogenase, are strongly inhibited by allicin [90]. 

---