柴达木枸杞和黑果枸杞中甜菜碱的测定

采用反相高效液相色谱法测定柴达木枸杞和黑果枸杞中甜菜碱的含量。以乙腈∶水(83∶17,V/V)为流动相,Hypersil NH2(250mm×4.6mm,5μm)为色谱柱,流速0.7mL/min,检测波长195nm,柱温30℃,外标法定量。结果表明,甜菜碱线性范围为2.94—29.40μg(r=0.9987),枸杞和黑果枸杞的平均回收率(n=5)分别为98.57%和99.07%。不同产地枸杞和黑果枸杞甜菜碱含量存有差异。该方法操作简便、重现性好,适用于测定枸杞和黑果枸杞甜菜碱含量。     

牛至的研究现状

牛至的挥发性及非挥发性成分是牛至的主要生物活性部位,具有许多有益的药理作用,包括抗菌和抗氧化活性.本文主要介绍从牛至中分离出的化学成分的结构以及其生物活性.     

Examination of Correlation between Histidine and Cadmium Absorption by Eleagnus angustifolia L .,Vitisvinifera L . and Nerium oleander L .Using HPLC-MS and ICP-MS

In this study,HPLC-MS and ICP-MS methods wereused for the determination of histidine and cadmiumin Eleagnusangustifolia L.,Vitisvinifera L.and Nerium oleander L.leaves taken from industrial area including Gaziantep and Bursa cities.To histidine determination by HPLC-MS,flow rate of mobile phase,fragmentor potential,injection volume and column temperature were optimized as 0.2mL·min~(-1),70V,15μL and 20℃,respectively.For extraction of histidine from plants,distilled water was used by applying on 90℃and 30min.The concentrations(as mg·kg~(-1))of histidine were found to be in range of 8~22for Eleagnusangustifolia L.,10~33for Vitisvinifera L.and 6~11for Nerium oleander L.The concentrations of cadmium were found to be in ranges of 6~21μg·kg~(-1) for Vitisvinifera L.15~110μg·kg~(-1) for Eleagnusangustifolia L.and 63~218μg·kg~(-1) for Nerium oleander L.     

Cryopreservation of Prunus avium L. embryogenic tissues

Embryogenic tissues from wild cherry (Prunus avium L.) were successfully cryopreserved by using a one-step freezing procedure. Cryoprotection consisted of a pretreatment on solid medium with increasing sucrose concentrations (0.25 M for 1 day, 0.5 M for 1 day, 0.75 M for 2 days, and 1.0 M for 3 days), followed by air desiccation to about 20 percent moisture content (fresh weight basis). This method was compared with a pretreatment on solid medium containing 5 percent DMSO and 2 percent proline, followed by immersion in a modified PVS2 cryoprotective solution. Pretreatment on solid medium with increasing concentrations of sucrose led to regrowth of frozen embryogenic tissues, and after 6 weeks of culture, growth was comparable to that of non-dehydrated and non-frozen tissues. By contrast, no regrowth was observed when embryogenic tissues were submitted to the solid/liquid pretreatment with DMSO/proline and a modified PVS2 solution.