高效液相色谱法测定不同产地枇杷叶中的3种黄酮类成分

建立了高效液相色谱同时测定枇杷叶中3种黄酮类成分的分析方法。该方法分析了不同产地枇杷叶中芦丁、槲皮素和山柰酚的含量差异。枇杷叶粉末用甲醇超声提取后，加盐酸回流，制备样品测试液。采用Diamonsil C18色谱柱（250 mm×4.6 mm，5 μm），以0.4%（v/v）磷酸水溶液-乙腈为流动相，梯度洗脱。分别对7个不同产地的枇杷叶样品中的芦丁、槲皮素和山柰酚进行测定。结果表明，芦丁、槲皮素、山柰酚在各自的质量浓度范围内线性关系良好（r>0.99），加标回收率分别为96.33%、95.81%和95.80%，RSD分别为6.48%、0.90%和3.02%。该方法操作简单、分离度好、重复性高。不同产地枇杷叶中3种黄酮类成分的含量存在差异，其中芦丁的差异最大，而山柰酚的含量最稳定且在不同产地样品中均可检出，或可用作枇杷叶药材质量控制的标志成分。

Determination of three flavonoids in loquat leaves from different producing areas by high performance liquid chromatography

A method for simultaneous determination of three flavonoids in loquat leaves was established by high performance liquid chromatography (HPLC), and the variations of contents of rutin, quercetin and kaempferol in loquat leaves from different producing areas were investigated. Powder of loquat leaves was extracted with methanol under ultrasonic extraction, then the lipid substances were recovered with hydrochloric acid before analyzed. A Diamonsil C18 column (250 mm×4.6 mm, 5 μm) was used. The mobile phases consisted of 0.4% (v/v) phosphoric acid and acetonitrile as gradient elution. The contents of rutin, quercetin and kaempferol in eight loquat leaf samples collected from seven producing areas were determined. Three flavonoids all showed good linear relationships in external standard method. The spiked recoveries of rutin, quercetin and kaempferol were 96.33%, 95.81% and 95.80%, with RSDs of 6.48%, 0.90% and 3.02%, respectively. The method can be applied in a rapid and easy way with high resolution and good repeatability. The contents of the three flavonoids in loquat leaves showed significant differences among producing areas, especially rutin. Kaempferol had been detected in all samples with a relative stable content. Kaempferol may be selected as an active ingredient for quality control of loquat leaf medicinal materials.