油橄榄叶中羟基酪醇含量及提取工艺研究

摘要

Many polyphenolic, antioxidants such as oleuropein, fiavonoids and hydroxytyrosol exist in olive leaves. The identification of hydroxytyrosol in different breeds of olive leaves was carried out by HPLC moritored at 230 nm with ODS column (φ 4.6 mm × 200 mm ,5 μm), MeOH-0.2 ％ acetic acid buffer 6∶94( volume ratio)as mobile phase at flow rate 1 mL/min. The contents of hydroxytyrosol were distributed from 0.3 ％ to 0.8 ％ in 10 breeds. The ultrasonic extract of hydroxytyrosol was studied by single factor and orthogonal experiment. The optimum extraction conditions were as follows: uhrasonie power 120 W, 90 ％ MeOH-H20 as extractant, material-liquid ratio 1∶ 20( g∶ mL), extraction time 20 min. Meanwhile, a single compound of 95 ％ content was seperated by AB-8 macroporous resin, silica gel column chromatography and preparative HPLC. It was identificated to be hydroxytyrosol by MS and NMR.%油橄榄含有橄榄苦苷、黄酮类和羟基酪醇等多酚抗氧化物.采用ODS(φ4.6mm×200mm,5μm)色谱柱,紫外检测波长为230 nm,甲醇-0.2%醋酸水溶液6:94(体积比)为流动相,流速1 mL/min,建立羟基酪醇的HPLC分析方法,对不同品种的油橄榄叶进行含量分析.结果表明:10个品种油橄榄叶中羟基酪醇质量分数范围在0.3%～0.8%之间,小菜星含量最高,配多灵含量最低.通过单因素和正交试验研究了超声波提取油橄榄叶中羟基酪醇的工艺,1g油橄榄叶粉末正交试验的优化结果为:功率120W、90%甲醇提取、料液比1:20(g:mL)、时间20 min.采用90%甲醇提取油橄榄叶,提取液经AB-8大孔树脂、硅胶柱层析和HPLC制备色谱,分离质量分数95%以上的单体,通过MS、NMR鉴定该化合物为羟基酪醇.