Influence of pH, concentration and light on stability of allicin in garlic (Allium sativum L.) aqueous extract as measured by UPLC

Abstract

Allicin extract was sensitive to pH and temperature of storage but not to light. Higher-concentration allicin solution was more stable.

Stability and extraction of bioactive sulfur compounds from Allium genus processed by traditional and innovative technologies

“…Further to this, greater stabilities were observed in situ, suggesting that endogenous components may have inhibited thiosulfinate transformations (Shen et al, 2002). Allicin present in aqueous extracts is temperature and pH sensitive (best stability in pH = 5-6), yet no effect of light was noticed (Wang et al, 2015). In addition, the extraction solvent was shown to effect the first-order decomposition reaction which decreased the activity against the bacterium, Helicobacter pylori (Cañizares et al, 2008).…”

“…Allicin can be recovered from the crushed plant using ethanol or water as extraction solvent (Bocchini et al, 2001;Wang et al, 2015), while alliin can be extracted using an acidic methanol-water mixture (Arnault et al, 2003;Nasim et al, 2010). It was found that garlic leaves are also rich in alliin compared to the callus embryo and the root (Nasim et al, 2010).…”

“…in their crude extracts has not been thoroughly investigated. However, some recent studies have shown that the decomposition of extracted compounds is dependent on the choice of solvent and polarity (Fujisawa et al, 2008;Ilic et al, 2011) combined with storage conditions (Wang et al, 2015).…”

Anti-cancerous/Anti-bacterial Activities of Allicin Generated In situ from Diastereo Pure Alliins by Alliinase

“…(+)-DL-alliin methyl ester was synthesized by mixing (+) alliin with anhydrous methanol in acidic conditions. The (+)-alliin methyl ester produced contains both (+)-L-alliin methyl ester (7) and (+)-D-alliin methyl ester (8) due to racemization [51,52]. Instead of fractional crystallization in 95% ethanol, RP-HPLC is used to purify compounds 6 and (+)-DL-alliin methyl ester.…”

“…Allicin is formed by the action of the enzyme alliinase on alliin. Purified allicin is unstable with a characteristic smell of garlic [7][8][9]. It decomposes into biologically less active oil-soluble organosulfur compounds (OSCs) such as diallyl sulfide, diallyl disulfide, diallyl trisulfide (allitridi), dithiins, and ajoene and some water-soluble OSCs such as Sallyl cysteine and S-allyl mercaptocysteine [10][11][12].…”