Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
J Agric Food Chem. 2022 Jul 6;70(26):7968-7980. doi: 10.1021/acs.jafc.2c02375. Epub 2022 Jun 21.
The fruits of Murr have long been consumed as health food and used in folk medicine in China. Apart from the well-known polysaccharides, the active small molecular constituents in this fruit have not been fully studied. In this work, a systematic phytochemical study was carried out to investigate the small molecules and their potential health benefits. Nine new polyphenolic glycosides, lyciumserin A-I (-), together with 16 known compounds (-), were isolated and elucidated by high-resolution electrospray ionization mass spectrometry and comprehensive NMR analyses in combination with chemical hydrolysis. Compounds , , and exhibited moderate inhibitory activity of monoamine oxidase B (MAO-B), while compounds (50 μM) and (100 μM) displayed significant neuroprotective effects (69.22 and 72.38% of cell viability, respectively) in the 6-hydroxydopamine-induced injury of the PC12 cell model (54.41%), comparable to the positive drug rasagiline (70.45%). The neuroprotective effect of and was further evidenced by the observation of the morphological change and fluorescein diacetate/propidium iodide staining. In addition, the levels of the major active compounds (, , /, and ) vary from 21.5 to 892.3 μg/g. This is the first report on phenolic glycosides from the fruits of Murr that possess both significant MAO-B inhibitory and neuroprotective effects, indicating the promising potential of the fruits for the development of health care products and even therapeutic agents for the treatment of Parkinson's disease and other neurodegenerative diseases.
枸杞的果实长期以来一直被作为健康食品食用，并在中国民间医学中使用。除了众所周知的多糖外，这种水果中的活性小分子成分尚未得到充分研究。在这项工作中，进行了系统的植物化学研究，以调查小分子及其潜在的健康益处。分离并通过高分辨率电喷雾电离质谱和综合 NMR 分析结合化学水解阐明了九个新的多酚糖苷，即 lyciumserin A-I（-），以及 16 种已知化合物（-）。化合物、、和表现出中等的单胺氧化酶 B（MAO-B）抑制活性，而化合物、（50 μM）和（100 μM）在 6-羟多巴胺诱导的 PC12 细胞模型损伤中表现出显著的神经保护作用（分别为细胞活力的 69.22%和 72.38%），与阳性药物雷沙吉兰（70.45%）相当。化合物和的神经保护作用进一步通过观察形态变化和荧光素二乙酸/碘化丙啶染色得到证实。此外，主要活性化合物（、、/和）的水平从 21.5 到 892.3 μg/g 不等。这是首次报道从枸杞果实中分离出具有显著 MAO-B 抑制和神经保护作用的酚糖苷，表明该果实具有开发保健品甚至治疗帕金森病和其他神经退行性疾病的治疗剂的巨大潜力。
