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81.
J. Kolehmainen R. Julkunen-Tiitto H. Roininen J. Tahvanainen 《Entomologia Experimentalis et Applicata》1995,74(3):235-243
The effects of individual phenolic glucosides and total glucoside fractions on the feeding behaviour of three willowfeeding
leaf beetles (Coleoptera: Chrysomelidae) were tested in the laboratory. Feeding preferences of the tested leaf beetles were
strongly influenced by certain phenolic glucosides which are typical secondary compounds of willows (Salicaceae:Salix).
Two of the tested leaf beetles,Galerucella lineola andLochmaea capreae showed rather similar responses to glucoside treatments. Both of them were strongly stimulated by total glucoside fractions
fromSalix triandra and by its major glucoside salidroside. The third species,Phatora vitellinae, was attracted most by the fractions fromS. myrsinifolia andS. pentandra, and by two related salicylate glucosides, tremulacin and salicortin. Food selection pattern of the tested beetles in the
laboratory concords fairly well with their distributions in the field and with the occurrence of phenolic glucosides in their
host willows. Phenolic glucoside extracts stimulated more feeding than individual pure glucosides. This indicates that different
compounds have synergistic effects in the feeding behaviour of leaf beetles. Our results clearly show that willow leaf beetles
select their food based on phenolic glucosides of their host plants. 相似文献
82.
In 3- and 14-day-old seedlings and in the leaves of Calendula officinalis the following sterols were identified: cholestanol, campestanol, stigmastanol, cholest-7-en-3-β-ol, 24-methylcholest-7-en-3β-ol, stigmast-7-en-3β-ol, cholesterol, campesterol, sitosterol, 24-methylcholesta-5,22-dien-3β-ol, 24-methylenecholesterol, stigmasterol and clerosterol. Sitosterol was predominant in young and stigmasterol in old tissues. Young tissues contained relatively more campesterol but in old tissues a C28Δ5,22 diene was present suggesting transformation of campesterol to its Δ5,22 analog, similar to that of sitosterol to stigmasterol. All the identified sterols were present as free compounds and also in the steryl esters, glucosides, acylated glucosides and water-soluble complexes. The variations in the amounts of these fractions in the embryo axes and cotyledons of 3- and 14-day-old seedlings and the distribution of individual sterols among the fractions are discussed. 相似文献
83.
The incorporation of mevalonate-[2-14C] into the free sterols, steryl esters, steryl glucosides, acylated steryl glucosides and water-soluble complexes was investigated and the sterols of each fraction were separated into stanols, Δ7 sterols, Δ5 sterols, stigmasterol, clerosterol and methylene-cholesterol. The stanols and Δ7 sterols were more strongly labelled in the steryl esters than in the free sterols. The Δ5 sterols and stigmasterol were more intensively labelled in the free sterols than in the steryl esters. All sterol types were more labelled in the steryl glycosides than in the acylated steryl glucosides. Stanols were probably formed from Δ7 or Δ5 precursors. 相似文献
84.
Twenty-three major components were detected in the methanol extractives of the heartwood of Eucalyptus sideroxylon. The components identified include resveratrol, resveratrol-β-glucoside, 3,3′-di- and 3,3′,4-tri-o-methylellagic acids and their glucosides. The 3,3′-di-o-methylellagic acid 4′-glucoside isolated had properties significantly different from those previously reported for this compound. Also present were gailic acid, catechin, ellagic acid, an unidentified stilbene, the ellagitannins D-6 and D-13, polymerized leucocyanidin and an oily material. The sapwood contained gailic acid, small amounts of ellagitannins and ellagic acids and traces of other components. The heartwood extractives of related eucalypt species were also examined. 相似文献
85.
Dried ligulate flowers of Matricaria chamomilla contain 7–9% glucosides of apigenin and 0.3–0.5% free apigenin. Glucosides were identified as apigenin 7-glucoside and a 1:3 mixture of the 2″- and 6″-acetates, as determined by 13C NMR analysis. 相似文献
86.
Twelve flavonoids including one new sulfate were isolated from Neurolaena lobata, and six known flavonoids were obtained from N. macrocephala. The new compound isolated from N. lobata is 6-hydroxykaempferol 3-methyl ether 7-sulfate, and the known flavonoids are 6-hydroxykaempferol 3,7-di-dimethyl ether, 6-hydroxykaempferol, 3-methyl ether 7-glucoside, 6-hydroxykaempferol 7-glucoside, quercetagetin and its 7-glucoside, quercetagetin 3,6- and 3,7-dimethyl ethers, quercetagetin 3-methyl ether 7-glucoside and 7-sulfate, 6-hydroxyluteolin 3′-methyl ether and 6-hydroxyluteolin 7-glucoside. The known flavonoids identified from N. macrocephala are quercetagetin 3,6- and 3, 7-dimethyl ethers, quercetagetin 6-methyl ether 7-glucoside, quercetagetin 3,6-dimethyl ether 7-glucoside, quercetagetin 7-glucoside and quercetagetin 3-methyl ether 7-sulfate. 相似文献
87.
Mass spectral data of a phytosterolin and its tetraacetate from Trianthema pentandra show that sitosterol-d(+)-glucoside reported earlier1 was a mixture of sitosteroI-d(+)-glucoside and stigmasterol-d(+)-glucoside. The structure of a ketone has been suggested as nonacos-1-en-4-one, on the basis of physicochemical data. The positions of the double bond and the carbonyl group have been established by MS and NMR data. This is the first report in plants of a C29 ketone with a terminal double bond and carbonyl group at position 4. 相似文献
88.
From Picrasma javanica, five new quassinoid glucosides, javanicinosides D-H, together with known quassinoids, neoquassin and picrasin A and triterpenoids, hispidol A and lanosta-7,24-dien-3-one were isolated. The structures have been determined by spectral analysis and chemical evidence. 相似文献
89.
The effects of 6-benzyladenine (BA), its 3-glucoside (BA-3-G) and 9-glucoside (BA-9-G), and its riboside (BA-R) on the rooting of primary leaf explants of Phaseolus vulgaris L. were compared, alone or in combination with indole-3-butyric acid (IBA). At all except the lowest concentration used (4.4 × 10–7
M), BA and BA-3-G reduced the number of roots and their averge length relative to a distilled water control. Addition of IBA (4.4 × 10–5
M) increased rooting beyond the control, but not to the level of IBA alone. This contrasted with BA-9-G where a response very similar to that of the control was recorded. The riboside of BA was more inhibitory than the free base, its effect extending to the lowest concentration used (4.4 × 10–7
M). 相似文献
90.
In addition to cardiospermin-5-(4-hydroxy)benzoate previously isolated from Sorbaria arborea, two further leucine-derived cyanogenic glucosides hav 相似文献