van Doorn Wouter G, Sinz Andrea, Tomassen Monic M
Wageningen University and Research Centre, PO Box 17, 6700 AA Wageningen, The Netherlands.
Phytochemistry. 2004 Mar;65(5):571-7. doi: 10.1016/j.phytochem.2003.12.008.
Visible symptoms of tepal senescence in cut Iris x hollandica (cv. Blue Magic) flowers were delayed by placing one cut daffodil flower (Narcissus pseudonarcissus, cv. Carlton) in the same vase. Addition of mucilage, exuded by daffodil stems, to the vase water had the same effect as the flowering daffodil stem. The active compound in the mucilage was identified as narciclasine (using LC/MS, GC/MS, 1H and 13C-NMR, and comparison with an authentic sample of narciclasine). The delay of senescence, either by mucilage or purified narciclasine, was correlated with a delayed increase in protease activity, and with a considerable reduction of maximum protease activity. Narciclasine did not affect in vitro protease activity, but is known to inhibit protein synthesis at the ribosomal level. Its effects on senescence and protease activity were similar to those of cycloheximide (CHX), another inhibitor of protein synthesis, but the effective narciclasine concentration was about 100 times lower than that of CHX. It is concluded that the delay of Iris tepal senescence by daffodil stems is due to narciclasine in daffodil mucilage, which apparently inhibits the synthesis of proteins involved in senescence.
通过将一朵切下的水仙花（水仙属，品种为卡尔顿）与切下的荷兰鸢尾（品种为蓝魔）花放在同一个花瓶中，可延缓鸢尾花被片衰老的明显症状。将水仙花茎分泌的黏液添加到花瓶水中，其效果与开花的水仙花茎相同。黏液中的活性化合物经鉴定为水仙克拉辛（使用液相色谱/质谱联用仪、气相色谱/质谱联用仪、1H和13C核磁共振，并与水仙克拉辛的标准样品进行比较）。无论是黏液还是纯化的水仙克拉辛导致的衰老延迟，都与蛋白酶活性的延迟增加以及最大蛋白酶活性的显著降低有关。水仙克拉辛不影响体外蛋白酶活性，但已知它能在核糖体水平抑制蛋白质合成。其对衰老和蛋白酶活性的影响与另一种蛋白质合成抑制剂环己酰亚胺（CHX）相似，但有效水仙克拉辛浓度比CHX低约100倍。得出的结论是，水仙花茎延缓鸢尾花被片衰老的原因是水仙黏液中的水仙克拉辛，它显然抑制了参与衰老的蛋白质的合成。
