Purified antioxidant from the medicinal mushroom Phellinus pini protects rat H9c2 cell against H2O2-induced oxidative stress

In this study, through the combination of AB-8 macroporous resin, Sephadex LH-20 column chromatography and semi-preparative HPLC, an antioxidant component was purified from the crude extract of Phellinus pini, thereby evaluating the cardioprotective effect of the fraction. As a result, total phenolic content of the 60% ethanol elution was increased by 4.8-fold after one run treatment on Sephadex LH-20 chromatography with gradient elution. After semi-preparative HPLC separation, the first peak (PP-S4-1) showed that inhibition ratio of erythrocyte hemolysis was 91.9%, and inhibition ratio of lipid peroxidation was also increased by 87.6%, at 50 mu g/ml (p < .01). Based on the results of ESI-MS, (HNMR)-H-1, (CNMR)-C-13, and RP-HPLC compared to many published results, PP-S4-1was identified as catechin (MW 290.015, C15H14O6). The results showed that PP-S4-1 pretreatment made cell viability increased, and the generation of reactive oxygen species (ROS) inhibited. Meanwhile, PP-S4-1 remarkably decreased the fluorescence intensity of Ca2+, and increased mitochondrial membrane potential (MMP; Delta psi m). In addition, PP-S4-1 could significantly inhibit the decrease of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activity as well as the increase of MDA content in H9c2 cells induced by H2O2. Moreover, pretreatment with PP-S4-1 significantly improved the morphological changes and prevented H2O2-induced DNA damage. Therefore, this study clarifies the ability of PP-S4-1 to treat H9c2 cell oxidative stress damage induced by H2O2 through its antioxidant effect. Practical applications This research is not only helpful to elaborate the cardioprotective effect of Phellinus pini but also can contribute to the development of health foods or drug supplements for heart disease in the future. This is the first report dealing with phenolic component and cardioprotective activity of a medicinal mushroom P. pini belonging to the genus Phellinus.