Zheleva-Dimitrova D, Gevrenova R, Nedialkov P, Kitanov G
Department of Pharmacognosy, Faculty of Pharmacy, Medical University Sofia, Dunav str. 2, 1000 Sofia, Bulgaria.
Phytochem Anal. 2007 Jan-Feb;18(1):1-6. doi: 10.1002/pca.940.
The content of the benzophenones, hypericophenonoside, neoannulatophenonoside, annulatophenonoside, annulatophenone, acetylannulatophenonoside and the xanthone derivative gentisein have been determined in aerial parts, leaves, flowers and stems of Hypericum annulatum Moris. Extraction of samples with methanol by magnetic stirring at room temperature allowed a good recovery of analytes (from 90.70% for gentisein to 103.81% for annulatophenonoside) and the precision of the entire procedure was < 6.05%. The subsequent HPLC separation and quantification was achieved using a Hypersil ODS C18 column and UV detection at 290 nm. The mobile phase comprised methanol and 20 mm potassium dihydrogen phosphate (adjusted to a pH of 3.19 with o-phosphoric acid), and gradient elution mode was applied. The detection limits were 0.03, 0.02 and 0.001 microg/mL for hypericophenonoside, acetylannulatophenonoside and gentisein, respectively. The total amounts of the phenolic compounds assayed ranged from 10.92 mg/g in stems to 82.86 mg/g in leaves. Hypericophenonoside was the dominant benzophenone present in the majority of the plant samples, being present in amounts between 7.54 +/- 0.25 mg/g in stems and 64.22 +/- 2.44 mg/g in leaves. Hypericophenonoside accounted for up to 77.50% of the components found in the leaves, whereas annulatophenonoside (6.29 +/- 0.15 mg/g) and acetylannulatophenonoside (8.95 +/- 0.09 mg/g) were detected in much lower quantities. In contrast to leaves, flowers showed a tendency towards higher contents of gentisein (9.35 +/- 0.07 mg/g) and neoannulatophenonoside (4.72 +/- 0.04 mg/g) than the other parts assayed.
已测定了环纹金丝桃地上部分、叶片、花朵和茎中苯甲酮类化合物、金丝桃苯甲酮糖苷、新环纹金丝桃苯甲酮糖苷、环纹金丝桃苯甲酮糖苷、环纹金丝桃苯甲酮、乙酰环纹金丝桃苯甲酮糖苷以及氧杂蒽酮衍生物染料木素的含量。室温下通过磁力搅拌用甲醇对样品进行萃取，可实现分析物的良好回收率（染料木素为90.70%，环纹金丝桃苯甲酮糖苷为103.81%），且整个过程的精密度<6.05%。随后使用Hypersil ODS C18柱并在290 nm处进行紫外检测实现高效液相色谱分离和定量分析。流动相由甲醇和20 mM磷酸二氢钾（用邻磷酸调节至pH 3.19）组成，并采用梯度洗脱模式。金丝桃苯甲酮糖苷、乙酰环纹金丝桃苯甲酮糖苷和染料木素的检测限分别为0.03、0.02和0.001 μg/mL。所测定的酚类化合物总量在茎中为10.92 mg/g至叶中为82.86 mg/g之间。金丝桃苯甲酮糖苷是大多数植物样品中主要的苯甲酮类化合物，在茎中的含量为7.54±0.25 mg/g至叶中的含量为64.22±2.44 mg/g之间。金丝桃苯甲酮糖苷在叶中占所发现成分的比例高达77.50%，而环纹金丝桃苯甲酮糖苷（6.29±0.15 mg/g）和乙酰环纹金丝桃苯甲酮糖苷（8.95±0.09 mg/g）的含量则低得多。与叶片相比，花朵中染料木素（9.35±0.07 mg/g）和新环纹金丝桃苯甲酮糖苷（4.72±0.04 mg/g）的含量有高于其他被测部分的趋势。
