姜黄素的增溶及稳定性研究

The solubility and stability of curcumin

姜黄素为难溶性且不稳定的一类天然食用色素,在食品、医药行业等领域中的应用受到极大限制。研究通过添加表面活性剂与助表面活性剂,以增加姜黄素在水性溶液中的溶解度。采用添加抗氧化剂、金属螯合剂以及调节p H值等手段,以色价损失率为评价指标,考察其对增溶后姜黄素溶液的稳定性影响。溶解度结果表明,当助表面活性剂与表面活性剂的用量质量比为1∶2时,可提高姜黄素溶解度至40 mg/g,且增溶后的姜黄素溶液为全水系,用水可稀释成澄清透明的水溶液。稳定性研究表明:抗氧剂的种类以及用量对姜黄素溶液的稳定性影响较大,以0.30%没食子酸丙酯的效果最佳;金属螯合剂对提高姜黄素稳定性的效果不及抗氧化剂;姜黄素溶液在强酸和碱性环境中的稳定性较差,当调节姜黄素溶液p H值为4.56时,其稳定性与加入0.30%没食子酸丙酯(propyl gallate,PG)的相当。

As a natural and edible pigment, curcumin＇ s usage in pharmaceutical and food fields is greatly limited due to its insolubility in water and un-stability in food. This study was to increase the solubility by adding surfactant and co-surfactant. The influence of antioxidants and metal chelator as well as the pH on the stability was studied and chroma loss rate was selected as the evaluation index. The study found that the best ratio on increasing solubility of curcumin was 1：2 （co-surfactant： surfactant） and solubility of curcumin reached 40 mg/g. The liquid system diluted with water is a clear and transparent solution. The results of stability study showed that the type and amount of antioxidants have large impact on the stability and 0.30% PG is best amount. The effect of metal chelator on the stability was less than that of the antioxidants. The stability was poor under both strong acid and base conditions. After adjusting pH to 4.56, the stability of curcumin was as good as adding 0.30% PG.