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151.
152.
A protein containing an XYPPX repeat and a C2 domain is associated with virally induced hypersensitive cell death in plants 总被引:1,自引:0,他引:1
Masaru Sakamoto 《FEBS letters》2009,583(15):2552-2556
In this study, we characterized a Capsicum hypersensitive response (HR)-associated gene, SS52, which encodes a protein that contains an N-terminal C2 domain and a C-terminal XYPPX repeat. Expression analyses revealed that SS52 and its homologue in Arabidopsis were induced by infection with incompatible viruses, indicating the conserved function of this gene. SS52 was not induced by treatment with defense-related hormones, but was induced by abiotic stresses, including wounding. Overexpression of SS52 in tobacco plants suppressed the spread of HR cell death and restricted the spread of an incompatible virus from local lesions. Collectively, the results suggest that SS52 negatively regulates plant HR cell death. 相似文献
153.
两种鹅掌楸繁殖成效的比较 总被引:1,自引:0,他引:1
通过交配设计结合花部性状调查对鹅掌楸(Liriodendron chktense Sarg.)与北美鹅掌楸(L.tulipifera Linn.)的繁殖资源分配与繁殖成效进行了比较.结果表明,鹅掌楸通过增加繁殖器官的数目以提高繁殖成效,而北美鹅掌楸则通过提高繁殖器官功效来保障繁殖成效.根据不同交配组合的子代出苗率分析表明,鹅掌楸总体的雄性繁殖成效高于北美鹅掌楸,而雌性繁殖成效低于北美鹅掌楸. 相似文献
154.
Nian Yun Yang Jin Ao Duan Er Xin Shang Li Juan Tian 《Phytochemical analysis : PCA》2010,21(2):144-149
Introduction – The aerial part Eupatorium lindleyanum is commonly used as an antipyretic and detoxicant clinically in traditional Chinese medicine. Our previous research showed that germacrane sesquiterpene lactones were its main active constituents, so the development of rapid and accurate methods for the identification of the sesquiterpene lactones is of great significance. Objective – To develop an HPLC‐PDA‐ESI‐MS/MS method capable for simple and rapid analysis of germacrane sesquiterpene lactones in the aerial part E. lindleyanum. Methodology – High‐performance liquid chromatography‐photodiode array detection‐electrospray ionization‐tandem mass spectrometry was used to analyze germacrane sesquiterpene lactones of Eupatorium lindleyanum. The fragmentation behavior of germacrane sesquiterpene lactones in a Micromass Q/TOF Mass Spectrometer was discussed, and 9 germacrane sesquiterpene lactones were identified by comparison of their characteristic data of HPLC and MS analyses with those obtained from reference compounds. Results – The investigated germacrane sesquiterpene lactones were identified as eupalinolides C (1), 3β‐acetoxy‐8β‐(4′‐hydroxy‐tigloyloxy)‐14‐hydroxy‐costunolide (2), eupalinolides A (3), eupalinolides B (4), eupalinolides E (5), 3β‐acetoxy‐8β‐(4′‐oxo‐tigloyloxy)‐14‐hydroxy‐heliangolide (6), 3β‐acetoxy‐8β‐(4′‐oxo‐ tigloyloxy)‐14‐hydroxy‐costunolide (7), hiyodorilactone B (8), and 3β‐acetoxy‐8β‐(4′‐hydroxy‐tigloyloxy)‐ costunolide (9). Compounds 6, 7 and 9 were reported for the first time. Conclusion – HPLC‐PDA‐ESI‐MS/MS provides a new powerful approach to identify germacrane sesquiterpene lactones in E. lindleyanum rapidly and accurately. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
155.
156.
从中华小苦荬全草的乙酸乙酯提取物中分离得到8个萜类化合物,通过波谱方法及文献对照分别鉴定为β-香树脂素(1),3β-羟基-20(30)-蒲公英甾烯(2),熊果-12-烯-3β-醇(3),羽扇豆醇(4),10-羟基艾里莫芬-7(11)-烯-12,8α-内酯(5),乌苏-12,20(30)-二烯-3β,28-二醇(6),3β,8α-二羟基-6β-当归酰基艾里莫芬-7(11)-烯-12,8β-内酯(7)和乌苏酸(8),化合物1~8均首次从该植物中分离得到。 相似文献
157.
158.
Dan Thi Thuy Hang Tran Thi Hong Hanh Chau Van Minh Phan Van Kiem Tran Huy Thai Dongho Lee Nguyen Tien Dat 《Phytochemistry letters》2011,4(3):377-379
A phytochemical investigation of the aerial parts of Eupatorium coelestinum led to the isolation of an amorphane sesquiterpene and a benzofuran glucoside. By means of spectroscopic methods, their structures were determined as 5α,8α-epoxy-4α,6β-dihydroxyamorphan-2-one (1) and 2R*,3S*-toxol-7-O-β-d-glucopyranoside (2). Compounds 1 significantly inhibited NF-κB activity in TNF-α-stimulated HeLa cells with the IC50 of 12.4 μM. 相似文献
159.
160.
芙蓉菊寡糖的分离纯化及其生物活性的研究 总被引:6,自引:2,他引:4
采用多级提取的方式从菊科植物芙蓉菊枝和叶中分离得到芙蓉菊多糖,脱色、除蛋白后,部分酸水解该多糖,将水解得到的寡糖经过活性炭柱层析得到四个洗脱组分。然后应用糖尿病药物筛选模型,考察这四个洗脱组分对于小鼠胰岛组织的胰岛素分泌水平的影响。正常胰岛细胞分泌中空白组胰岛素含量为7.694:芙蓉菊寡糖水洗脱组分的胰岛素含量为8.506;5%乙醇洗脱组分的胰岛素含量为9.689。结果表明,芙蓉菊寡糖水、5%乙醇洗脱组分有一定的促进胰岛素分泌的作用。 相似文献