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31.
Xingfeng Guo Daijie Wang Wenjuan Duan Jinhua Du Xiao Wang 《Phytochemical analysis : PCA》2010,21(3):268-272
Introduction – Flavonoids, the primary constituents of the petals of Nelumbo nucifera, are known to have antioxidant properties and antibacterial bioactivities. However, efficient methods for the preparative isolation and purification of flavonoids from this plant are not currently available. Objective – To develop an efficient method for the preparative isolation and purification of flavonoids from the petals of N. nucifera by high‐speed counter‐current chromatography (HSCCC). Methodology – Following an initial clean‐up step on a polyamide column, HSCCC was utilised to separate and purify flavonoids. Purities and identities of the isolated compounds were established by HPLC‐PAD, ESI‐MS, 1H‐NMR and 13C‐NMR. Results – The separation was performed using a two‐phase solvent system composed of ethyl acetate–methanol–water–acetic acid (4 : 1 : 5 : 0.1, by volume), in which the upper phase was used as the stationary phase and the lower phase was used as the mobile phase at a flow‐rate of 1.0 mL/min in the head‐to‐tail elution mode. Ultimately, 5.0 mg syringetin‐3‐O‐β‐d‐glucoside, 6.5 mg quercetin‐3‐O‐β‐d‐glucoside, 12.8 mg isorhamnetin‐3‐O‐β‐d‐glucoside and 32.5 mg kaempferol‐3‐O‐β‐d‐glucoside were obtained from 125 mg crude sample. Conclusion – The combination of HSCCC with a polyamide column is an efficient method for the preparative separation and purification of flavonoids from the petals of N. nucifera. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
32.
藕莲是莲(Nelumbo nucifera Gaertn.ssp.nucifera)的3种类型之一,在我国作为水生蔬菜栽培的历史愈两千年。对国家种质资源圃中来自17个省和直辖市的68份藕莲资源的19个形态和农艺性状进行了观察,并对其遗传变异进行了分析。结果发现整藕重与主藕重、主藕长和第三节粗成极显著正相关。通径分析结果表明主藕重对整藕重的正向效应最高(0.982)。主成分分析结果显示前4个成分占总变异的77.33%。结果还显示对整藕重负效应最高的是主藕重/整藕重(-0.296)。聚类分析发现所有藕莲资源可分为5组。 相似文献
33.
对从国家种质资源圃中选取的40份花莲种质资源的19个形态性状进行了观察。结果发现花型、花瓣数、雌蕊是否瓣化、雌蕊瓣化程度和根茎颜色与花蕾形状呈显著正相关,其中花型、花瓣数和根茎颜色与花蕾形状呈极显著高度相关。通径分析表明现蕾期对花型有显著正向效应(0.552),其次是花瓣数(0.516)和根茎颜色(0.368)。与花型呈显著负相关的性状有花瓣长(-0.801)、现花期(-0.558)和叶宽(-0.451)。主成分分析显示前四个成分累计贡献率达65.68%。聚类分析将所有材料分为四组。 相似文献
34.
MARGARITA MAURO‐HERRERA ALAN W. MEEROW JAMES W. BORRONE DAVID N. KUHN RAYMOND J. SCHNELL 《Molecular ecology resources》2006,6(3):904-906
Coconut (Cocos nucifera L.) WRKY sequences containing single nucleotide polymorphisms (SNPs) and one microsatellite repeat were used to develop 10 informative markers. These markers were evaluated in 15 genotypes representing six coconut cultivars. SNP‐containing alleles were detected by single‐strand conformation polymorphism (SSCP) analysis. The number of detected alleles ranged from two to four. Five pairs of loci were in linkage disequilibrium in the test population. These markers are currently being evaluated in more individuals/cultivars to determine their value in estimating the genetic diversity of this species. 相似文献
35.
Nelumbo nucifera (Gaertn.) grows by extending a creeping rhizome through anaerobic sediments. Nodes form at intervals along the rhizome, each producing a single leaf, and gas canals channel air from the leaves throughout the petioles and rhizomes. The gas flow pathway was mapped by casting the canals in growing shoots with silicone and by blowing air through complexes of rhizomes and petioles. Air from a leaf flows to a rhizome through one of two petiolar canal pairs, joining with the lowermost of three canal pairs in the rhizome through a chamber in the node. The lowermost canal pair links these nodal chambers along the length of a rhizome, allowing air from a node to flow both forward, toward a growing shoot, and backward, toward preceding leaves. These linked chambers also connect with the middle pair of canals on their proximal side, enabling flow to proceed backward along the rhizome to an adjacent node. A chamber in the next node then diverts the flow into the upper canal pair. This pair leads to a third node and chamber from which the air vents to the atmosphere through the second petiolar canal pair. Thus, pressurised air from one leaf must flow backward through two nodes before it returns to the atmosphere. Forward flow also ventilates a shoot's growing tip, with air from the lowermost canal pair entering a chamber in the developing node which, as described above, connects with the middle canal. This allows the air to reverse direction at the tip and enter the vent flow pathway. 相似文献
36.
Isolation and characterization of microsatellite markers in the sacred lotus (Nelumbo nucifera Gaertn.) 总被引:1,自引:0,他引:1
LEI PAN ZHIWU QUAN SHUANGMEI LI HONGGAO LIU XINFANG HUANG WEIDONG KE YI DING 《Molecular ecology resources》2007,7(6):1054-1056
The sacred lotus (Nelumbo nucifera Gaertn.) is an aquatic plant of economic and ornamental importance in China. From an (AG)n‐enriched genomic library, 24 microsatellites were isolated and identified by using the (fast isolation by the AFLP of sequences containing repeats) FIASCO protocol. Eleven loci showed polymorphism with two to six alleles per locus. These markers yielded 42 alleles in a survey of 32 accessions of the sacred lotus. Eleven effective primer pairs of simple sequence repeats were designed and will be used as genetic markers to evaluate the fine‐scale population structure of the sacred lotus in the future. 相似文献
37.
Saurabh Prabhu Sarah R. Dennison Bob Lea Timothy J. Snape Iain D. Nicholl Iza Radecka 《植物科学评论》2013,32(5):303-320
Anionic antimicrobial peptides (AAMPs) have been identified in a wide variety of plant species with net charges that range between ?1 and ?7 and structures that include: extended conformations, α-helical architecture and cysteine stabilized scaffolds. These peptides commonly exist as multiple isoforms within a given plant and have a range of biological activities including the ability to kill cancer cells as well as phytopathogenic bacteria, fungi, pests, molluscs, and other predatory species. In general, the killing mechanisms underpinning these activities are poorly understood although they appear to involve attack on intracellular targets such as DNA along with compromise of cell envelope integrity through lysis of the cell wall via chitin-binding and/or permeabilisation of the plasma membrane via lipid interaction. It is now becoming clear that AAMPs participate in the innate immune response of plants and make a major contribution to the arsenal of defence toxins produced by these organisms to compensate for their lack of some defence mechanisms possessed by mammals, such as mobility and a somatic adaptive immune system. Based on their biological properties, a number of potential uses for plant AAMPs have been suggested, including therapeutically useful anticancer agents and novel antimicrobial compounds, which could be utilized in a variety of scenarios, ranging from the protection of crops to the disinfection of hospital environments. 相似文献
38.
R.T. Ichiki M. Murata S. Takano T.T. Oo H.T. Nguyen W. Suasa-ard 《Biocontrol Science and Technology》2011,21(12):1423-1435
The coconut hispine beetle, Brontispa longissima (Gestro), is a serious invasive pest that infests young unopened fronds of coconut palms (Cocos nucifera L.) in Southeast Asia. We previously developed the first artificial diet for rearing B. longissima larvae, which contained a leaf powder of young coconut fronds. Because the fronds are required for healthy growth of coconut palms, it is necessary to reduce their use for rearing the beetles. In this study, we tested two new artificial diets for the beetle larvae, which contained the leaf powders of mature coconut leaves or orchard grass (Dactylis glomerata L.). Brontispa longissima successfully developed from hatching to adulthood on both the mature coconut leaf diet and orchard grass diet. The beetles reared on the mature coconut leaf diet and orchard grass diet developed faster than those reared on the young coconut leaf diet. Fecundity and egg hatchability of beetles did not differ among the three diet treatments. We then examined the suitability of beetle larvae or pupae reared on each diet as hosts for two specialist endoparasitoids, Asecodes hispinarum Boucek and Tetrastichus brontispae Ferriere. The survival rate from oviposition to adult emergence for A. hispinarum was 43.8% in hosts reared on a young coconut leaf diet, 77.1% on a mature coconut leaf diet, and 85.7% on an orchard grass diet. For T. brontispae, the survival rate was 70.0% in hosts reared on the young coconut leaf diet, 38.1% on the mature coconut leaf diet, and 66.7% on the orchard grass diet. Our results indicate these artificial diets can be useful for rearing B. longissima and its two parasitoids, helping to reduce the costs of mass rearing these insects. 相似文献
39.
40.
Shun‐ichiro Takano Keiji Takasu Tsutomu Fushimi Ryoko T. Ichiki Satoshi Nakamura 《Entomological Science》2014,17(2):265-268
The coconut hispine beetle Brontispa longissima (Gestro) supposedly originated in Indonesia and Papua New Guinea. It is a serious invasive pest of the coconut palm Cocos nucifera L. in Southeast and East Asia. In Japan, it has established itself using Satakentia liukiuensis (Hatushima) H.E. Moore as a main host on Ishigaki and Iriomote Islands where C. nucifera is rare. To assess the probability of further establishment of B. longissima in novel habitats where C. nucifera and S. liukiuensis are not available, we examined the suitability of four common palm species in Japan for oviposition and immature development of B. longissima: Chrysalidocarpus lutescens (Bory) H. Wendl., Phoenix roebelenii O'Brien, S. liukiuensis and Washingtonia filifera (Linden ex André) H. Wendl. When seedlings of the four palm species were placed in pots in an experimental field on Ishigaki Island, all four species were inhabited and infested by wild B. longissima adults. Oviposition and immature development were observed on P. roebelenii and S. liukiuensis but not on C. lutescens and W. filifera. When field‐collected adults were released into mesh bags enclosing the potted seedlings, they oviposited on all four species. The eggs developed into adults on P. roebelenii, S. liukiuensis and W. filifera. On C. lutescens, however, hatched larvae died during the first or second instar. 相似文献