Wang Haiping, Li Xixiang, Liu Xinyan, Shen Di, Qiu Yang, Zhang Xiaohui, Song Jiangping
Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
J Sci Food Agric. 2015 Jul;95(9):1838-44. doi: 10.1002/jsfa.6884. Epub 2014 Sep 25.
Garlic is one of the most important bulb vegetables and is mainly used as a spice or flavoring agent for foods. It is also cultivated for its medicinal properties, attributable to sulfur compounds, of which allicin is the most important. However, the stability of allicin in garlic extract is not well understood. In this study, using UPLC, the stability of allicin extracted in water from garlic was evaluated in phosphate buffer at different temperatures under light and dark conditions.
At room temperature, allicin in aqueous extract was most stable at pH 5-6 but degraded quickly at lower or higher pH. It began to degrade within 0.5 h and was not detectable after 2 h when the pH was higher than 11 or lower than 1.5. It degraded quickly when the temperature was higher than 40 °C and especially higher than 70 °C. At room temperature, allicin in water could be stored for 5 days without obvious degradation. Higher concentrations of allicin in solution were somewhat more stable than low concentrations.
Allicin extract was sensitive to pH and temperature of storage but not to light. Higher-concentration allicin solution was more stable.
大蒜是最重要的球茎蔬菜之一，主要用作食品的香料或调味剂。它也因其药用特性而被种植，这归因于硫化合物，其中蒜素是最重要的。然而，蒜素在大蒜提取物中的稳定性尚未得到充分了解。在本研究中，使用超高效液相色谱法（UPLC），在光照和黑暗条件下，于不同温度的磷酸盐缓冲液中评估了从大蒜中提取的蒜素在水中的稳定性。
在室温下，水提取物中的蒜素在pH 5 - 6时最稳定，但在较低或较高pH下会迅速降解。当pH高于11或低于1.5时，它在0.5小时内开始降解，2小时后无法检测到。当温度高于40°C尤其是高于70°C时，它会迅速降解。在室温下，水中的蒜素可以储存5天而无明显降解。溶液中较高浓度的蒜素比较低浓度的蒜素稍微更稳定一些。
蒜素提取物对储存的pH和温度敏感，但对光照不敏感。较高浓度的蒜素溶液更稳定。
