中文摘要：

从内生真菌Berkleasmium sp.Dzf12多糖（EPS、WPS和SPS）分别制备出相应的寡糖（EOS、WOS和SOS）,研究寡糖对宿主盾叶薯蓣（Dioscorea zingiberensis）培养细胞和幼苗防御相关酶活性的影响。对于培养细胞,浓度为0.25 mg/m L的EOS处理24 h,苯丙氨酸解氨酶（PAL）和多酚氧化酶（PPO）活性达最大值,分别为对照的6.19倍和7.16倍;浓度为0.05 mg/m L的EOS处理48 h,过氧化物酶（POD）活性达最大,是对照的4.63倍。对于幼苗,浓度为2.5 mg/m L的EOS,处理48 h,PAL活性达最大值,为对照的6.21倍;处理24 h,PPO活性达最大值,为对照的4.80倍;处理48 h,POD活性达最大值,为对照的6.09倍。在3种寡糖中,EOS是最有效的诱导子。结果表明,用内生真菌Berkleasmium sp.Dzf12寡糖处理宿主盾叶薯蓣培养物能有效提高防御相关酶的活性,激活其防卫机制。

英文摘要：

Three oligosaccharides （ EOS, WOS and SOS） were prepared from their corresponding polysaceharides （ EPS, WPS and SPS） of Berkleasmium sp. Dzfl2, an endophytic fungal strain of Dioscorea zingiberensis. The effects of oligosaccharides on the activities of defense-related enzymes phenylalanine ammonia lyase （PAL）, polyphenoloxidase （PPO） and perexidase （POD） in suspension cell and seedling cultures of D. zingiberensis were investigated. For the suspension cell cultures,the highest activities of PAL and PPO were induced by 0.25 mg/mL of EOS at 24 h after treatment,which were 6.19-and 7.16-fold of control,respectively. While the POD activity was increased to the maximum by 0.05 mg/mL of EOS at 48 h after treatment,which was 4.63-fold of control. For the seedling cultures,the highest activities of PAL, PPO and POD were induced by 2.5 mg/mL of EOS at 48,24 and 48 h,respoctively,which were 6.21-,4.80-and 6.09- fold of control, separately. Among three oligosaccharides, EOS was the most effective elicitor to induce activities of defense-related enzymes in D. zingiberensis cultures. The results demonstrated that the increased activities of PAL, PPO and POD elicited by the oligosacchafides may be related to the activation of defensive mechanisms of D. zingiberensis suspension cell and seedling cultures.