苦楝果实中川楝素粗提物稳定性研究

摘要

To study the stability of toosendanin crude extract with solvent , temperature, pH, illumination, ascor-bic acid and metal ions .The toosendanin crude extract was treated with different solvents ( methanol , ethanol , dim-ethyl sulfoxide , the mixture of xylene and methanol ) , different temperatures ( -4℃, 4℃, 20℃, 40℃, 60℃and 80℃), different pH values (2, 4, 6, 8, 10), ultraviolet ray of 253 nm and dark, adding ascorbic acid and different metal ions (K+, Na+, Ca2+, Mg2+, Al3+, Fe3+), then, the toosendanin contents were determined by UV at 215 nm in the 0th, 2nd, 4th, 6th, 8th, 10th, 20th and 30th days.The results showed that the stability of the toosendanin decreased with the increase of the polarity of the solvents or the increase of the temperature . The toosendanin was stable at the pH value of 4-8.It was degraded when exposed under the ultraviolet ray of 253 nm. Other factors had few effects on the stability .The optimal condition for toosendanin production process and storage from Melia azedarach fruit is that methanol as the solvent , below 20℃, acid environment and dark .%为研究溶剂、温度、 pH值、光照、添加抗坏血酸和常见金属离子对川楝素稳定性的影响，苦楝果实中川楝素粗提物在甲醇、乙醇、二甲基亚砜、二甲苯＋甲醇混合液4种不同溶剂，－4℃、4℃、20℃、40℃、60℃和80℃6种不同温度， pH 2、 pH 4、 pH 6、 pH 8和pH 10等5种不同pH值，253 nm紫外线照射和暗箱，加抗坏血酸，不同金属离子即K＋、 Na＋、 Ca2＋、 Mg2＋、 Al3＋和Fe3＋处理下，分别于第0天、2天、4天、6天、8天、10天、20天和30天取样，在215 nm处用紫外可见分光光度法测定川楝素含量，计算川楝素的降解率。结果表明，川楝素的稳定性随溶剂的极性增加而减弱、随温度的升高而降低， pH值在4～8时较稳定，遇光易分解，抗坏血酸的添加、金属离子对其稳定性影响不大。苦楝果实中川楝素生产、贮存、应用条件建议为，溶剂为甲醇、温度在室温以下、酸性、避光。