益智仁之成分分離及其對β-amyloid損傷PC-12細胞之保護作用

Abstract

Yizhiren is the dry fruit of Alpinia oxyphylla Miq. as a kind of crude drug in traditional chinese medicine. According to the description of Chinese pharmacopoeia, the kind of fruit has some healthy functions correspond to spleen and kidney. Lee-Tan was an ancient doctor in China descripted the benefit of this fruit as making people become wiser. There are many clinical applications to enhance brain functions and human memory by using Yizhiren, but its pharmacological mechanisms are still not yet clear. Extracting 20 kg Yizhiren by 50% EtOH and then separating by diaion HP-20 with 25%, 50%, 75% and 95% EtOH could collect four fractions, AO-A (113.73 g), AO-B (81.59 g), AO-C (79.39 g) and AO-D (94.58 g). Extracting 5 kg Yizhiren by steam distillation method could collect 11.0 g essential oil marked as AO-E. Four pure compounds, Nootkatone (AO-1), α-cyperone (AO-2), epi-α-cyperone (AO-3) and Yakuchinone A (AO-4) were from further purifications of AO-C, AO-D and Yizhiren methanol extract. AO-1 and AO-4 are marker constituent representative sesquiterpene and heptane derivative in Yizhiren, respectively. The contents of AO-1 and AO-4 were 7.27 ± 0.74 mg/g and 0.60 ± 0.19 mg/g in Yizhiren by analyzing four batches crude drug from local market. Compounds AO-1 and AO-4 were almost absent in fraction AO-A and AO-B but rich in fraction AO-C, AO-D and AO-E. In AO-C, AO-1 and AO-4 were 39.14 ± 2.69 mg/g and 4.92 ± 0.34 mg/g, respectively. There were 248.14 ± 35.83 mg/g and 24.46 ± 3.64 mg/g in AO-D, respectively. And there were 179.88 ± 6.04 mg/g and 7.42 ± 0.52 mg/g in AO-E. The protective effects were obviously on β-amyloid injury in PC-12 cell by using these fractions AO-A, AO-B, AO-C, AO-D and AO-E and pure compounds AO-1 and AO-4. All the fractions could also decrease the intracellular calcium and ROS.