Research Group on Quality, Safety and Bioactivity of Plant Foods, Department of Food Science and Technology, CEBAS (CSIC), P.O. Box 164, 30100 Campus University Espinardo, Murcia, Spain.
Food Chem. 2012 Sep 15;134(2):894-904. doi: 10.1016/j.foodchem.2012.02.201. Epub 2012 Mar 10.
HPLC-DAD-ESI/MS(n) was used to ascertain the authenticity of two certified and two commercial Bauhinia forficata Link samples. Different flavonoids profiles were obtained, involving 39 compounds. Just kaempferol-3-O-(2-rhamnosyl)rutinoside was found in all analysed samples. Five compounds were common to the certified samples of B. forficata Link and B. forficata Link subsp. pruinosa (Vogel) Fortunato & Wunderlin, being kaempferol derivatives the most representative ones. The phenolic composition of B. forficata Link subsp. pruinosa (Vogel) Fortunato & Wunderlin is described herein for the first time, accounting for eight compounds, while 10 new compounds were identified in B. forficata Link. Commercial B. forficata Link showed higher contents of quercetin derivatives, in addition to the presence of myricetin derivatives and flavonoids-(galloyl)glycosides, for which the MS fragmentation pattern is reported for the first time. B. forficata Link and the two commercial samples were able to inhibit α-glucosidase, with EC(50) values lower than that found for acarbose. Mild effects on cholinesterases were observed with the certified samples, while commercial ones were more effective. The same behaviour was observed concerning the scavenging of DPPH, nitric oxide and superoxide radicals. The presence of high contents of quercetin derivatives in commercial samples seems to directly influence their biological properties. The differences between phenolic profiles and their relation with the authenticity of commercial samples are discussed.
采用高效液相色谱-二极管阵列检测-电喷雾串联质谱（HPLC-DAD-ESI/MS(n)）法鉴定了两份有证对照品和两份市售紫荆花样品的真伪。得到了不同的黄酮类化合物图谱，共鉴定出 39 种化合物。所有分析样品中均发现了山柰酚-3-O-(2-鼠李糖苷)芦丁苷。有证对照品紫荆花和紫荆花亚种柔毛紫荆（Vogel）Fortunato & Wunderlin 中共有 5 种化合物，其中以山柰酚衍生物最为典型。本文首次描述了紫荆花亚种柔毛紫荆的酚类成分，共鉴定出 8 种化合物，而在紫荆花中则鉴定出 10 种新化合物。市售紫荆花中槲皮素衍生物含量较高，此外还存在杨梅素衍生物和黄酮类-(没食子酰基)糖苷，首次报道了它们的 MS 裂解模式。紫荆花、两种市售样品均能抑制α-葡萄糖苷酶，其 EC(50)值低于阿卡波糖。有证对照品对胆碱酯酶有轻微的抑制作用，而市售对照品则更有效。对 DPPH、一氧化氮和超氧自由基的清除能力也表现出类似的行为。市售样品中槲皮素衍生物含量较高，似乎直接影响了它们的生物学特性。讨论了酚类图谱的差异及其与市售样品真伪的关系。
