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1.
Hyphenated liquid chromatography – diode array detection – solid phase extraction – nuclear magnetic resonance spectroscopy (LC-DAD-SPE-NMR) was used to investigate the phytochemical composition of aerial parts and roots of Wachendorfia thyrsiflora (Haemodoraceae). Eleven phenylphenalenones and related compounds were identified in the aerial parts of the plant, ten compounds were found in the roots, and four additional compounds occurred in both plant parts. Twelve compounds are previously unreported natural products including five alkaloids (phenylbenzoisoquinolinones) are described here for the first time. In the work presented here, phenylphenalenones with an intact C19 core structure were found only in the roots. Oxa analogs with a C18O scaffold occurred both in the roots and in the aerial plant parts, while most of the aza analogs with a C18N scaffold were detected in the aerial plant parts. This distribution pattern suggests that phenylphenalenones form in the roots, then the intact C19 skeleton is converted into oxa analogs in the roots, translocated into the leaves and further reacted with amines or amino acids to form aza analogs (phenylbenzoisoquinolin-1,6-dione alkaloids).  相似文献   

2.
Root and shoot growth of semi-dwarf and taller winter wheats   总被引:1,自引:0,他引:1  
Investigations are reported of root and shoot growth in semi-dwarf and taller winter wheat varieties grown in contrasting soils over three years. Comparisons were made of the distribution with depth of roots, estimated by injecting rubidium-86 into stem bases and counting the content in soil cores. The relative ability to absorb phosphate from different zones was measured from the recovery in aerial parts of 32P injected into the soil at different depths. The distribution of dry matter in roots and aerial parts, and total root length, was measured using soil cores and samples of aerial parts taken during the growth of the crop. Relative growth rates of the aerial parts followed a sigmoid curve, but those of the roots showed little change between germination and anthesis. There was little evidence of varietal differences in root growth, though there was some indication that at depth the roots of the semi-dwarf varieties were more extensive and absorbed more phosphate than those of the taller varieties.  相似文献   

3.
The present study reports the chemical composition of the headspace volatiles (HS) and essential oils obtained from fresh Chaerophyllum aromaticum root and aerial parts in full vegetative phase, as well as biological activities of their essential oils and MeOH extracts. In HS samples, the most dominant components were monoterpene hydrocarbons. On the other hand, the essential oils consisted mainly of sesquiterpenoids, representing 73.4% of the root and 63.4% of the aerial parts essential oil. The results of antibacterial assay showed that the aerial parts essential oil and MeOH extract have no antibacterial activity, while the root essential oil and extract showed some activity. Both of the tested essential oils exhibited anticholinesterase activity (47.65% and 50.88%, respectively); MeOH extract of the root showed only 8.40% inhibition, while aerial part extract acted as an activator of cholinesterase. Regarding the antioxidant activity, extracts were found to be more effective than the essential oils.  相似文献   

4.
Carbohydrates constitute the principal reserves in temperate woody fruit plants and are depleted during winter, particularly around the time of bud-break before new growth makes good the losses. Movement of reserves between underground and aerial parts occurs during winter. All perennial parts show alternate depletion and replenishment but root extremities may undergo irreversible depletion and die. Interconversions between soluble carbohydrates and polysaccharides indicate a balance between degradation and synthesis. High growth potential is associated with high starch/starch + sugar ratio.  相似文献   

5.
Five amino acids are accumulated during vegetative growth of Neurospora crassa, particularly.during the prestationary growth phase. Alanine, glutamine, glutamate, arginine and ornithine.comprised over 80% of the total amino acid pool in the mycelium. Amino acid pools of different amino acid auxotrophs were followed during the partial transformation of a mycelial mat into an aerial mycelium. The mycelial mat under starvation and in direct contact with air rapidly formed aerial mycelium, which produced thereafter a burst of conidia. During this process,glutamine and alanine in the mycelial mat were consumed more rapidly than other amino acids;in the growing aerial mycelium, glutamate and glutamine were particularly accumulated. Of the amino acids that were initially accumulated in the mycelial mat, only a high glutamine pool was required for aerial mycelium growth induced by starvation. This requirement for glutamine could not be satisfied by a mixture of the amino compounds that are synthesized via glutamine amidotransferase reactions. It is proposed that glutamine serves as a nitrogen carrier from the mycelial mat to the growing aerial mycelium.  相似文献   

6.
Summary Growth inhibitors are washed down from the aerial vegetative parts ofParthenium hysterophorus L. during rain. These get adsorbed to soil particles thereby rendering the substratum inhibitory. The trichomes covering the vegetative parts contain inhibitors. The trichomes which get easily detached from dry parts when happen to settle on leaf surface of other plants in high quantity, reduce the chlorophyll and dry matter content in those species.Part I appeared in Plant and Soil53, 27 (1979).  相似文献   

7.
陈黎  吴卫  郑有良   《广西植物》2006,26(6):697-701
分别对鱼腥草16个不同居群幼嫩地上和地下部分的氨基酸成分进行高效液相色谱分析。结果发现,鱼腥草不同居群的氨基酸含量不尽相同,同一居群幼嫩地上茎叶和地下茎的氨基酸含量也有差异,多以地上茎叶高于地下茎。在分析的17种氨基酸中,所有居群均含有16种氨基酸,都不含Cys-SS-Cys。地上部分氨基酸中Glu含量最高,His含量最低;地下部分氨基酸中Glu含量最高,Tyr含量最低。地上部分氨基酸总量以W01-16为最高,而地下部分氨基酸总量以W01-99为最高,分别为27.89mg/g和15.46mg/g。蕺菜与峨眉蕺菜间氨基酸成分间无显著差别。鱼腥草种质资源氨基酸含量与染色体数目间相关不显著。  相似文献   

8.
《Phytochemistry》1986,25(2):535-537
The aerial parts of Centaurea coronopifolia afforded three new germacronolides, two of which are closely related to balsamin. The third is a new derivative of stizolicin, which is also present. The aerial parts also yielded four 6-methoxylatedflavonoids an spectroscopic methods.  相似文献   

9.
The major endogenous cytokinins, Z, ZR, DHZ, DHZR, iP and iPR in pistachio seedlings (Pistacia vera L. cv. Ohadi) were purified by HPLC and their identities confirmed using GC-MS. The aerial parts of two-year old pistachio seedlings including mature leaves, young leaves, lateral buds, debarked stems and bark were subjected to analysis. All of the above mentioned cytokinins were identified in the aerial parts except DHZ which was only present in mature leaves. Z-type cytokinins contributed almost 43% of the total cytokinins. ZR and DHZR were identified as the major ribosides and iP as the main base. The greatest concentration of ZR was detected in the bark, amounting to about 48%. DHZR and ZR constituted the major portion of the total cytokinins detected in both young and mature leaves while Z was detected as a minor cytokinin in leaves. The sharp increase of iP concentration during leaf maturation indicates that mature leaves are probably capable of de novo biosynthesis of cytokinins. The absence of DHZ (except in mature leaves) and the presence of considerable concentrations of DHZR in pistachio stems suggest that these tissues are able to metabolize DHZ to DHZR. The large amount of ZR in pistachio leaves suggests that root-derived ZR is transported into the leaves after loading into the xylem. The presence of high amounts of iP in pistachio lateral buds indicates that iP has been accumulated in these parts. The occurrence of a totally different cytokinin distribution pattern in buds, as compared with the other aerial parts, possibly results from their different metabolism.  相似文献   

10.
ABSTRACT Feral swine (Sus scrofa) impact resources through their destructive feeding behavior, competition with native wildlife, and impacts to domestic animal agriculture. We studied aerial gunning on feral swine to determine if aerial gunning altered home range and core area sizes, distances between home range centroids, and distances moved by surviving individuals. We collected data before, during, and after aerial gunning in southern Texas. Using Global Positioning System collars deployed on 25 adult feral swine at 2 study sites, we found home range and core area sizes did not differ before and after aerial gunning. However, feral swine moved at a greater rate during the aerial gunning phase than during the before and after periods. We concluded that aerial gunning had only minor effects on the behavior of surviving swine and that this removal method should be considered a viable tool in contingency planning for a foreign animal disease outbreak.  相似文献   

11.
Van Damme  E. J. M.  Peumans  W. J. 《Planta》1990,182(4):605-609
A sensitive immunosorbent assay was developed to quantify the lectin in different tissues ofGalanthus nivalis (snowdrop) andNarcissus cv. Carlton (daffodil) and follow the distribution of the lectin during the life cycle of the plants. The lectin in snowdrops and daffodils occurs in almost all plant tissues. Moreover, in many tissues the lectin is the most prominent protein. High lectin concentrations are found in the bulb where the lectin accounts for up to 15% of the total protein during the resting period. However, as the shoot grows and the plant turns on to flowering the lectin content rapidly decreases. Soon after flowering the lectin accumulates in the new bulb units. Whereas in daffodil the lectin concentration in the aerial plant parts is about one order of magnitude lower than in the bulb, lectin concentrations in the upper parts of snowdrop are similar to those in the bulb. The lectin in the former tissues is already present before the sprout emerges. As the shoot starts to grow lectin concentrations in leaves, stems and flower parts gradually decrease so that at flowering time virtually all lectin has disappeared from the aerial parts. The highest lectin concentrations are found in the ovary and increase, initially, as the sprout emerges from the bulb. This work was supported in part by grants from the ‘Nationale Bank’ and the National Fund for Scientific Research (Belgium). W.J.P. is a Senior Research Associate and E.J.M.V.D. Research Assistant of this fund.  相似文献   

12.
《Phytochemistry》1986,26(1):187-190
The aerial parts of Podolepis hieracioides afforded eight γ-pyrones all derived from 2-methoxy-3,5-dimethyl-6-undecyl-γ-pyrone (podopyrone). The aerial parts of Cassinia longifolia gave in unusual high concentration two sesquiterpene acids, both related to costic acid. The structures were elucidated by highfield NMR spectroscopy. The structures of some previously reported pyrones are revised.  相似文献   

13.
Deoxypodophyllotoxin content of the aerial parts of Anthriscus sylvestris Hoffm. growing at different altitudes was evaluated in comparison to the roots. The lignan accumulation in ground parts was at least double compared to aerial ones. In addition antioxidant-guided fractionation of the crude methanol extract of aerial parts was performed with the 2,2-diphenyl-1-picrylhydrazyl (DPPH) test. Active fractions contained mainly luteolin-7-O-glucoside and chlorogenic acid. Antioxidant properties of both crude extract and isolated compounds were also investigated with the Briggs-Rauscher (BR) oscillating reaction. A satisfactory agreement between the results obtained with the two methods was observed.  相似文献   

14.
The composition of the volatile fraction of Polygonum bistorta L. (also known as bistort or snakeroot) was investigated. Fresh aerial parts of this plant species were collected in the Western Italian Alps during the summer at three different phenological stages, namely vegetative, flowering, and fruiting, and steam-distilled in a Clevenger-type apparatus. The oils accounted for 0.004 to 0.010% of the fresh plant material, and their compositions were determined by GC/FID and GC/MS. The composition of the oils during the vegetative period varied both in quantity and quality; several classes of compounds were found with a predominance of alcohols in the vegetative phase, terpenes and linear-chained saturated hydrocarbons in the flowering phase, while saturated aliphatic acids and their methyl esters were predominant in fruiting phase. The most abundant compounds were 3-methylbut-3-en-1-ol in the vegetative phase, linalool in the flowering phase, and dodecanoic acid and its methyl ester in the fruiting phase. The obtained essential oils were then tested against two major bee pathogens, i.e., Paenibacillus larvae and Melissococcus plutonius, and against a reference bacterial species, Bacillus subtilis. Data were compared to those obtained with reference standards used against those pathogens such as the essential oils obtained from leaves and bark of Cinnamomum zeylanicum (cinnamon), and the antibiotic oxytetracyclin.  相似文献   

15.
绞股蓝(Gynostemma pentaphyllum)茎端具有在秋季钻入土中发育为根状茎以越冬和增殖的现象。观察绞股蓝根状茎的形成过程及其组织结构特点,并检测根状茎不同发育阶段和不同节段的内源激素含量。结果表明,正常茎端首先发育为膨大的变态茎并钻入土中,在土中发育成根状茎并进行增殖,腋芽或侧枝的增殖倍数为2.28,来春可萌发出多株新苗。正常芽、变态茎和根状茎的基本结构相似,但后两个阶段的淀粉鞘细胞、髓和髓射线细胞中含有丰富的淀粉粒。生长素、赤霉素和茉莉酸的含量在正常茎端中最高,变态茎端次之,根状茎最低。三种激素在各茎端从芽尖段、弯曲段、膨大段至稳定段的含量总体表现为先升后降趋势。三种激素在变态茎的弯曲段含量明显升高,并在膨大段达到最高值,而生长素在根状茎的弯曲段含量最高,反映它们对相应节段发育的促进作用。  相似文献   

16.
Effects of temperature were studied on the current and following season's growth of shoots from chilled rhizomes of Variegated Solomon's Seal. The rate of progress to completed elongation of the aerial shoot in chilled plants increased linearly with increasing temperature up to 28°C (24 h mean). A post‐chilling thermal time of 658 ± 47°Cd (> ‐1.3°C) was required for aerial shoots to become fully extended. Temperatures of 28°C and 33°C accelerated aerial shoot senescence and decreased rhizome and root dry weights, as compared with 18°C and 23°C treatments. Leaf number and variegation were not affected by temperature treatments during current growth season and all plants produced 12–13 leaves with between 7% and 9% leaf area variegated. Leaf variegation, however, was significantly increased in plants that had been grown after chilling at 28°C during the preceding growing season. Proteins of approximately 26, 32 and 62 kDa were present in the green parts of leaves but not in the white parts.  相似文献   

17.
A simple, rapid and reliable reversed-phase high-performance liquid chromatographic method for the determination of tagitinin C, an anti-plasmodial sesquiterpene lactone isolated from the aerial parts of Tithonia diversifolia, has been developed. The assay has been used to quantify tagitinin C in various extracts of the aerial parts of T. diversifolia.  相似文献   

18.

Background  

Cadmium (Cd) translocation and accumulation in the grain and aerial plant parts of rice (Oryza sativa L.) is an important aspect of food safety and phytoextraction in areas with contaminated soil. Because control of Cd translocation and accumulation is likely to be determined by the plants genetics, the Cd contents of grain and the aerial parts of rice may be manipulated to improve food safety and for phytoextraction ability. This study studied Cd translocation and accumulation and their genetic control in aerial parts of rice to provide a starting point for improving food safety and phytoextraction in Cd-contaminated soils.  相似文献   

19.
Fausto Lona 《Plant biosystems》2013,147(1-2):228-232
Abstract

INHYBITION OF NODULATION IN METEOR PEA, BY NICTOPHASIC TREATMENT WITH FAR-RED RADIATION. — A remarkable inhybiting effect of far-red light (given to the aerial part of the plants as a flash befor and during the nictophase) on Pea root nodulation, has been achivied through some preliminary experiments. The relations between irradiated aerial parts and the activities of the underground organs in general, are being studied in the picture of photo-chromoperiodism.

Relations with the action of gibberellic acid (GA) are preliminary attempted. The inhibiting action of GA is far less striking in comparison with that of far-red radiation. Kinetin favores, at some extent, the nodulation process.  相似文献   

20.
Chemical examination of aerial parts of Dracocephalum heterophyllum resulted in isolation of phenolic alkaloids, including two flavonoidal alkaloids, drahebephins A and B, one imidazole alkaloid with a phenolic substituent, drahebenine, together with 15 other known compounds. Their structures were established by extensive spectroscopic data analyses. Due to the stereogenic center in the pyrrolidin-2-one ring, the flavonoidal alkaloids are chiral, although they were isolated as racemates. The enantiomers were separated by HPLC using a chiral phase and stereochemically characterized by circular dichroism (CD) spectroscopy. The structure of compound drahebenine was established by X-ray crystallography.  相似文献   

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