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91.
Van Damme Els J.M. Barre Annick Rougé Pierre Peumans Willy J. 《Plant molecular biology》1997,33(3):523-536
cDNA clones encoding the bark and seed lectins from Sophora japonica were isolated and their sequences analyzed. Screening of a cDNA library constructed from polyA RNA isolated from the bark resulted in the isolation of three different lectin cDNA clones. The first clone encodes the GalNAc-specific bark lectin which was originally described by Hankins et al. whereas the other clones encode the two isoforms of the mannose/glucose-specific lectin reported by Ueno et al.. Molecular cloning of the seed lectin genes revealed that Sophora seeds contain only a GalNAc-specific lectin which is highly homologous to though not identical with the GalNAc-specific lectin from the bark. All lectin polypeptides are translated from mRNAs of ca. 1.3 kb encoding a precursor carrying a signal peptide. In the case of the mannose/glucose-specific bark lectins this precursor is post-translationally processed in two smaller peptides. Alignment of the deduced amino acid sequences of the different clones revealed striking sequence similarities between the mannose/glucose-binding and the GalNAc-specific lectins. Furthermore, there was a high degree of sequence homology with other legume lectins which allowed molecular modelling of the Sophora lectins using the coordinates of the Pisum sativum, Lathyrus ochrus and Erythrina corallodendron lectins. 相似文献
92.
槐树试管苗在移栽驯化过程中叶表面结构的扫描电镜观察 总被引:6,自引:1,他引:5
用扫描电子显微镜观察了槐树试管试管苗在移栽驯化及大田生长过程中叶表面结构的变化。结果表明:随着移栽驯化及大田生长过程的延长,表皮细胞周缘突起增多,细胞之间相互嵌合,连结紧密;表皮蜡质结晶密度、长度及蜡质厚度逐渐增加,其结晶由“星”状转化为针状及棒状;气孔器密度及气孔开度由大到小,气孔器下陷程度增加。显示出试管苗在移栽驯化及田间生长过程中,叶表面结构对环境的适应性,其主要变化向着防止水分过度散失的方 相似文献
93.
苦刺总生物碱和槐果碱的抗溃疡作用 总被引:1,自引:0,他引:1
实验发现苦刺总生物碱具有对抗水浸应激性小鼠溃疡,吲哚美辛加乙醇所致小鼠溃疡、盐酸性大鼠溃疡和结扎大鼠幽门性溃疡形成作用。但其成分之一的槐果碱仅能对抗前两种模型的溃疡形成。 相似文献
94.
Evidence for the recent dispersal of Sophora (Leguminosae) around the Southern Oceans: molecular data 总被引:2,自引:0,他引:2
Kathryn A Hurr Peter J Lockhart Peter B Heenan David Penny 《Journal of Biogeography》1999,26(3):565-577
Aim The aim is to use DNA sequence data to test between vicariance and long range dispersal (by floating seed-pods) explanations for the origin and range of the Edwardsia species of Sophora (Sophoreae: Papilionoideae: Leguminosae). Location This group is widely distributed around the South Pacific and into the South Atlantic on both continental fragments and oceanic islands. Methods DNA sequences from an intergene region (atpB-rbcL) of the chloroplast were determined for twelve taxa (including outgroups) and used to test these hypotheses. Sophora fossils were used to calibrate the evolutionary tree. Results The Edwardsia group of Sophora appears monophyletic and is well differentiated from other Sophora. However, the genetic difference between species within the South Pacific and to the South Atlantic is very low. Main conclusionsThe results eliminate vicariance explanations for this section of Sophora and strongly support an origin from other (non-Edwardsia) Sophora in the north-west Pacific. Dispersal appears initially to be to Tuvalu, Lord Howe Island, New Zealand, and subsequently across the South Pacific, probably within the last 2–5 million years. Dispersal of buoyant Sophora seeds to oceanic islands is the most likely explanation of its distributions. Fossil pollen dates in New Zealand are consistent with the conclusion. 相似文献
95.
96.
国槐(Sophora japonica)种子成分分析 总被引:2,自引:0,他引:2
为更深入了解国槐种子的生理特性及其综合利用价值,对种子主要成分进行研究,结果表明,国槐种子中蛋白质含量最高,其次为总糖和脂肪;谷氨酸,精氨酸和天冬氨酸是组成种子蛋白质的主要成分;种子油脂以不饱和脂肪酸油酸和亚油酸为主,各种维生素Vc含量最高,各种化学成分在叶和胚轴+胚根中含量存在差异。 相似文献
97.
苦参异戊烯基黄酮类化合物的化学,活性及其生物合成研究进展 总被引:8,自引:0,他引:8
综述苦参(Sophora flavecens Aiton.)异戊烯基黄酮类化合物的化学,活性及其生物合成研究进展。 相似文献
98.
Jian-Chun Li Wei-Feng Dai Xiao-Qiong Zhou Kai-Rui Rao Zhi-Jun Zhang Dan Liu Xuan-Qin Chen Rong-Tao Li Hong-Mei Li 《化学与生物多样性》2021,18(4):e2001066
Three new matrine-type alkaloids, 8β-hydroxyoxysophoridine ( 1 ), 9β-hydroxysophoridine ( 2 ), 9β-hydroxyisosophocarpine ( 3 ), together with one known analog, 11,12-dehydromatrine ( 4 ), were isolated from the seeds of Sophora alopecuroides L. The structures of new compounds were elucidated using extensive spectroscopic techniques including the experimental and calculated ECD data. The anti-inflammatory activities of all the isolates on NO production in RAW 264.7 cells stimulated by lipopolysaccharide were evaluated. Among them, 8β-hydroxyoxysophoridine ( 1 ) showed a significant inhibitory effect with an IC50 value of 18.26 μM. 相似文献
99.
不同径级国槐行道树重金属富集效能比较 总被引:6,自引:1,他引:6
采用ICP-OES测定北京市台基厂大街行道树国槐各器官中7种重金属(Cd、Cr、Ni、Cu、Mn、Pb、Zn)含量,比较不同径级国槐重金属富集效能。结果表明:国槐中重金属含量因胸径级、器官、元素种类不同而存在差异。各径级国槐重金属含量大小总体趋势为ZnMnCuPbCrNiCd,各器官中树皮和根对重金属的吸收能力最强,其次是叶和枝,树干对重金属的吸收能力最弱。不同径级国槐对重金属的富集能力存在差异,表现为小径级中径级大径级。国槐各器官中重金属积累量大小顺序为根干枝叶,重金属积累量随着胸径级扩大和生物量的增加而增加。综合比较不同径级国槐重金属年均积累量、单位面积富集量和单位空间富集量,小径级(20≤DBH30 cm)国槐富集效能最高。 相似文献
100.
以牛心朴子和苦豆子为供试植物,小菜蛾幼虫为供试试虫,采用浸渍法测定了两种植物提取物复配后对小菜蛾幼虫的联合毒力。结果表明:牛心朴子与苦豆子提取物复配后具有增效作用,其中以干粉质量比为2∶1时增效作用最显著,其共毒系数(CTC)为248.30。复配物对小菜蛾幼虫具有显著的触杀活性,质量浓度为20.00 mg/mL时,72 h校正死亡率可以达到100%,致死中浓度LC50=2.0747 mg/mL。 相似文献