Alonso-Salces Rosa M, Ndjoko Karine, Queiroz Emerson F, Ioset Jean R, Hostettmann Kurt, Berrueta Luis A, Gallo Blanca, Vicente Francisca
Departamento de Química Analítica, Facultad de Ciencias, Universidad del País Vasco/Euskal Herriko Unibertsitatea E-48080 Bilbao, Spain.
J Chromatogr A. 2004 Aug 13;1046(1-2):89-100.
Apple polyphenols were characterised by means of hyphenated techniques such as HPLC coupled to UV photodiode array detection (LC-DAD) and to mass spectrometry (LC-MS). LC-MS using atmospheric pressure ionisation (APCI) in the positive ion mode provided the molecular weight, the number of hydroxyl groups, the number of sugars and an idea about the substitution pattern of the polyphenols. LC-DAD with postcolumn addition of UV shift reagents afforded precise structural information about the position of the free hydroxyl groups in the polyphenolic nucleus. Five isorhamnetin glycosides, two hydroxyphloretin glycosides and quercetin were reported in apple peel for the first time. Postcolumn addition of UV shift reagents in LC-DAD analysis confirmed the presence of isorhamnetin glycosides and not the isomeric glycosides of rhamnetin. Moreover, isorhamnetin-3-O-rhamnoglucoside was identified unambiguously by comparison with a standard. These results are relevant not only from a chemotaxonomic point of view, but also in the control of authenticity of fruit derived products in order to detect fraudulent admixtures.
苹果多酚通过联用技术进行表征，如与紫外光电二极管阵列检测（LC-DAD）和质谱联用（LC-MS）的高效液相色谱法。在正离子模式下使用大气压电离（APCI）的LC-MS可提供多酚的分子量、羟基数量、糖的数量以及有关其取代模式的信息。柱后添加紫外位移试剂的LC-DAD可提供有关多酚核中游离羟基位置的精确结构信息。首次在苹果皮中报道了五种异鼠李素糖苷、两种羟基根皮苷糖苷和槲皮素。在LC-DAD分析中柱后添加紫外位移试剂证实了异鼠李素糖苷的存在，而非鼠李素的异构糖苷。此外，通过与标准品比较明确鉴定出异鼠李素-3-O-鼠李糖葡萄糖苷。这些结果不仅从化学分类学角度来看具有重要意义，而且对于控制水果衍生产品的真伪以检测欺诈性掺假也具有重要意义。
