Yokota Junko, Takuma Daisuke, Hamada Atsuhide, Onogawa Masahide, Yoshioka Saburo, Kusunose Masahiko, Miyamura Mitsuhiko, Kyotani Shojiro, Nishioka Yutaka
Department of Biomedical Science, Kochi Medical Graduate School, Nankoku, Japan.
Biol Pharm Bull. 2006 Mar;29(3):467-71. doi: 10.1248/bpb.29.467.
We have clarified that Eriobotrya japonica seed extract has strong antioxidative activity, and is effective for the prevention and treatment of various diseases, such as hepatopathy and nephropathy. In this study, to investigate the influences of components of Eriobotrya japonica seed extract on its antioxidative activity, extracts were prepared using various solvents (n-hexane (Hex), ethyl acetate (EtOAc), n-butanol (n-BuOH), methanol (MeOH) and H2O) and the antioxidative activity of the solvent fractions and components was evaluated based on the scavenging of various radicals (DPPH and O2(-)) measured by the ESR method and the inhibition of Fe3+-ADP induced NADPH dependent lipid peroxidation in rat liver microsomes. The radical scavenging activities and inhibitory activities on lipid peroxidation differed among the solvent fractions and components. In the n-BuOH, MeOH and H2O fractions, radical scavenging activity and inhibitory activity on lipid peroxidation were high. In addition, these fractions contained abundant polyphenols, and the radical scavenging activity increased with the polyphenol content. In the low-polar Hex and EtOAc fractions, the radical scavenging activity was low, but the lipid peroxidation inhibition activity was high. These fractions contained beta-sitosterol, and the inhibitory activity on lipid peroxidation was high. Based on these findings, the antioxidative activity of Eriobotrya japonica seed extract may be derived from many components involved in a complex mechanism, resulting in high activity.
我们已经阐明，枇杷种子提取物具有很强的抗氧化活性，对预防和治疗各种疾病有效，如肝病和肾病。在本研究中，为了研究枇杷种子提取物的成分对其抗氧化活性的影响，使用各种溶剂（正己烷（Hex）、乙酸乙酯（EtOAc）、正丁醇（n-BuOH）、甲醇（MeOH）和水）制备提取物，并基于通过电子自旋共振（ESR）法测量的各种自由基（DPPH和O2(-)）的清除以及大鼠肝微粒体中Fe3+-ADP诱导的NADPH依赖性脂质过氧化的抑制来评估溶剂级分和成分的抗氧化活性。溶剂级分和成分之间的自由基清除活性和对脂质过氧化的抑制活性有所不同。在正丁醇、甲醇和水级分中，自由基清除活性和对脂质过氧化的抑制活性较高。此外，这些级分含有丰富的多酚，并且自由基清除活性随多酚含量增加而增加。在低极性的正己烷和乙酸乙酯级分中，自由基清除活性较低，但脂质过氧化抑制活性较高。这些级分含有β-谷甾醇，并且对脂质过氧化的抑制活性较高。基于这些发现，枇杷种子提取物的抗氧化活性可能源自参与复杂机制的许多成分，从而导致高活性。
