桂花色素清除亚硝酸盐作用的研究

[目的]研究桂花色素对亚硝酸盐的清除作用。[方法]采用石油醚从桂花中提取色素,再以N-萘基乙二胺显色法测定桂花色素对亚硝酸盐的清除率,同时以VC为对照。[结果]桂花色素剂量从0.5 mg增加到11.0 mg,对20μg亚硝酸盐的清除率从(9.47±2.48)%增加到(77.79±1.35)%,量效之间基本呈线性关系(r=0.971 0);剂量增加到12.0 mg时,清除率不再增加。VC剂量从0.01 mg增加到0.30 mg,对20μg亚硝酸盐的清除率从(3.59±1.85)%增加到(93.09±0.61)%,量效之间线性关系较差(r=0.920 0),呈"S"状曲线;剂量增加到0.40 mg,清除率也不再增加。[结论]桂花色素对亚硝酸盐有显著的清除作用,但其作用小于VC(P<0.001)。

桂花黄色素微波预处理提取及抑菌作用研究

以汉中桂花为原料,通过微波辅助提取法,以乙醇浓度、回流时间、回流温度及料液比等因素为变量,黄色素提取率为响应值,设计正交试验得到黄色素提取最佳工艺条件。试验结果表明,最佳提取工艺为乙醇浓度80%、回流时间80 min、回流温度80℃、料液比1∶20(g/m L)。在此条件下,桂花黄色素提取率可达18.42%。同时,抑菌试验证实,桂花黄色素对大肠杆菌、金黄色葡萄球菌、枯草杆菌、沙门氏菌均有较好的抑菌效果。对金黄色葡萄球菌的抑菌活性最为显著,其最低抑菌浓度(MIC)为1.0 mg/m L;对大肠杆菌、枯草杆菌、沙门杆菌的MIC均为1.5 mg/m L。此外,桂花黄色素对食品还具有一定的防腐功能。

Stability and degradation of hydroxysafflor yellow A and anhydrosafflor yellow B in the Safflower injection studied by HPLC-DAD-ESI-MS^n

Safflower is a popular Chinese medicinal plant and Safflower injection is extensively used for the clinical treatment of cerebrovascular and cardiovascular diseases. In this study, HPLC-DAD-ESI-MSn was utilized to study the stability and degradation of the two major but chemically unstable bioactive compounds hydroxysaffior yellow A and anhydrosaffior yellow B, in Safflower injection. The impact of light irradiation, temperature, and pH on the stability of these two compounds were studied. The results showed that hydroxysafflor yellow A and anhydrosafflor yellow B could degrade at high temperature （〉60 ℃） or extreme pHs （pH ≤ 3.0 or 〉7.0）, but not under light irradiation. The common degradation product was p-coumaric acid. Chemical structures of the other degradation products were characterized by LC-MS. Hypothetical degradation pathways were proposed. In addition, ADP-induced platelet aggregation tests showed that the degradation of anhydrosaffior yellow B could reduce the anticoagulation activities of Safflower injection. Our results suggest that temperature and pH are critically important for the preparation and storage of Safflower injection.