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41.
The gene Po in pollen of Petunia hybrida Vilm. controls a discrete step in flavonoid biosynthesis. In recessive genotypes, naringenin-chalcone (4, 2,4,6-tetrahydroxychalcone) is accumulated, whereas, under the influence of the wild-type allele flavonols and anthocyanins are formed. Enzymic investigations on anthers of four genetically defined lines with different pollen colouration revealed a clear correlation between accumulation of naringenin-chalcone and deficiency of chalcone isomerase (EC 5.5.1.6). The results allow the conclusion that chalcone is the first product of the flavanone synthase reaction in anthers of Petunia hybrida and that chalcone isomerase is essential for the formation of flavonols and anthocyanins. These results were similar to those previously obtained with Callistephus chinensis (L.) Nees.Abbreviations EGME
ethylen glycol monomethyl ether
- MeOH
methanol
- CI
chalcone isomerase
- HOAc
acetic acid
- TLC
thinlayer chromatography 相似文献
42.
Hans-Peter Kleber Hermann Seim Harald Aurich Erich Strack 《Archives of microbiology》1977,112(2):201-206
Zusammenfassung Die Verwertung von Carnitin und Carnitinderivaten (O-Acylcarnitine, Carnitincarboxyl-derivate) und strukturverwandten Trimethylammoniumverbindungen (Betaine und Stickstoffbasen) durch Acinetobacter calcoaceticus wurde anhand des Wachstums und des quantitativen Nachweises der Metabolite untersucht. Der Stamm wuchs auf l-Carnitin, l-O-Acylcarnitinen und -Butyrobetain als jeweils einziger C-Quelle. Der Verbrauch dieser Verbindungen und das Wachstum korrelierten mit der Spaltung der C-N-Bindung und mit dem gebildeten Trimethylamin. d-Carnitin wurde metabolisiert, wenn als zusätzliche C-Quelle l-Carnitin im Nährmedium vorhanden war, oder wenn die Bakterien mit l-oder dl-Carnitin vorinkubiert worden waren. Mit d-Carnitin als einziger C-Quelle wuchsen die Bakterien jedoch nicht. Die Bakterien oxidierten Cholin zu Glycinbetain in Gegenwart einer zusätzlichen C-Quelle, Glycinbetain selbst wurde nicht assimiliert. In Hinsicht auf den Abbau quaternärer Stickstoffverbindungen besitzt Acinetobacter calcoaceticus im Vergleich zu anderen Carnitin-verwertenden Bakterienarten einen für ihn charakteristischen Stoffwechselweg.
Utilization of trimethylammonium-compounds by Acinetobacter calcoaceticus
The utilization of carnitine and carnitine derivatives (O-acylcarnitines, carnitine carboxylderivatives) and structure-related trimethylammonium-compounds (betaines and nitrogen-bases) by Acinetobacter calcoaceticus was studied by means of the control of growth and the quantitative detection of metabolites. The strain grew only on l-carnitine, l-O-acylcarnitines, and -butyrobetaine as the sole carbon sources. The utilization of these compounds and the growth correlated with the cleavage of the C-N bond and thereby with the formation of trimethylamine. d-Carnitine was metabolized, if an additional carbon source, like l-carnitine, was present in the incubation mixture, or if the bacteria were preincubated with l-or dl-carnitine, but no growth was observed on d-carnitine as the sole carbon source. The bacteria oxidized choline to glycinebetaine in the presence of additional carbon sources, glycinebetaine itself was not assimilated. With regard to the catabolism of quaternary nitrogen compounds Acinetobacter calcoaceticus shows a different pathway in comparison with other bacterial species metabolizing carnitine.相似文献
43.
The electron impact mass spectra of 19 trimethyl silylated flavonol mono-, di- and -triglycosides are reported for the first time. All spectra show wel 相似文献
44.
Ferdinand Bohlmann Karl-Heinz Knoll Christa Zdero Pradip Kumar Mahanta Michael Grenz Albert Suwita Dorothea Ehlers Ngo Le Van Wolf-Rainer Abraham Arvind Anant Natu 《Phytochemistry》1977,16(7):965-985
Investigation of about 50 Senecio species has afforded many new substances, in addition to known compounds. Present in these plants are 23 fura 相似文献
45.
In Calendula officinalis leaves 66% of all steryl forms are present in the ‘microsomal fraction’ (IV), 24% in the mitochondrial and Golgi membranes (III), 5% in the ‘chloroplast’ (II), 4% in the ‘cell wall and membrane’ (I) fraction and 1%. in the cytosol. Free sterols, their esters, glycosides and acylated glycosides are present in varying proportions in all cellular subtractions. Mevalonate-[214C] labelling of sterols derived from various steryl forms showed that free sterols and all their derivatives, i.e. steryl esters and glucosides, are formed in fraction IV and are then translocated to other organelles. Fraction III is the main site of glycosylation of transported sterols as well as of acylation of steryl glycosides. 相似文献
46.
From three Mikania species, three new labdanic acid and two kaurenic acid derivatives have been isolated together with known compounds and four new germacranolides, differing only in the ester moiety. 相似文献
47.
The aerial parts of the South African composite Printzia laxa contain two manoyl oxides and three clerodane derivatives together with two further acids, which belong to a new type of diterpene, biogenetically closely related to the clerodanes. The structures have been elucidated by spectroscopic methods. The constituents may indicate some relationship of Printzia to the tribe Astereae. 相似文献
48.
Ferdinand Bohlmann 《Phytochemistry》1978,17(2):319-320
49.
Christine A. Williams 《Phytochemistry》1978,17(4):729-734
In a leaf survey of 61 species of the Bromeliaceae, an unexpectedly wide spectrum of flavonoid constituents was encountered. The family is unique amongst the monocotyledons in the frequency and variety of flavonoids with extra hydroxylation or methoxylation at the 6-position. More common flavonols (in 43% of species) and flavones (in 13%) are distributed throughout the family whereas the rarer flavonoid classes are restricted to one or two of the three subfamilies. Thus 6-hydroxyflavones were found in both the Pitcairnioideae (in 50%) and the Tillandsioideae (in 14%) but patuletin (in 19%), gossypetin (in 1 species) and methylated 6-hydroxymyricetin derivatives (in 24%) were detected only in the Tillandsioideae. A new flavonol, 6,3′,5′-trimethoxy-3,5,7-4′-tetrahydroxyflavone, was identified as the 3-glucoside in Tillandsia usneoides and a new glycoside, patuletin 3-rhamnoside, in Vriesea regina. Myricetin glycosides were found only in the Bromelioideae and their presence here and the concomitant absence of 6-hydroxyflavonoids could indicate the primitive condition of this subfamily. The flavonoid results, in toto, confirm the view based on morphology, that the Bromeliaceae occupies an isolated position in relation to other monocot families. 相似文献
50.
An Australian member of the tribe Senecioneae, Bedfordia salicina, contains besides known compounds new dimeric eremophilenolides, new kolevane derivatives, a kaurenic acid and several further sesquiterpenes, most of them related to xanthatine. The structures are elucidated mainly by spectroscopic methods and by some chemical transformations. The chemotaxonomic aspects of these findings are discussed briefly. 相似文献