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1.
-The production of essential oils in Pinus pinaster increases with the age of the seedlings, being higher in plants grown under continuous illumination. In the seedlings, nearly all the terpene is α- and β-pinene, the relative proportions of which are completely reversed between the 6th and 10th days of growth, regardless of the illumination period. Another reversion takes place after 60–65 days, the proportion found in the adult pine being very constant with α-pinene as the main component. The amount of oil in seedlings from high resin yielding parent trees was 4-fold higher than that in seedlings of normal (wild type) seeds. This finding is interesting because it can be employed for the preselection at the early stage of seedling of seeds to be used in forestry to obtain plantations of a high resin yield. 相似文献
2.
Vapor-phase chromatographic patterns obtained from the essential oils from three populations of Thymus villosus subsp. lusitanicus are discussed. Two infraspecific chemovars and two chemoforms can be distinguished. 相似文献
3.
J. Bricout 《Phytochemistry》1974,13(12):2819-2823
The bitter constituents of Gentiana lutea L. roots were isolated and identified by mass spectrometry. Gentiopicroside, swertiamarin, amarogentin were characterized and their abundance evaluated. Amarogentin was shown to be the main bitter constituent of the roots. By cultivation of Gentiana lutea, roots with a high content in amarogentin can be obtained in 2 yr. 相似文献
4.
Cell-free extracts and acetone powder extracts from Pinus pinaster seedlings contain mevalonate kinase which phosphorylates mevalonic acid (MVA). t 相似文献
5.
Three new compounds, recedensolide Ia, recedensic acid IIa and isocalolongic acid IIIa, have been isolated from Calophyllum recedens bark (Gutt 相似文献
6.
A mixture of C28 and C29 sterols have been isolated from Leptosphaeria typhae grown in vitro on “oat water” and characterized by GLC and MS. Mono-, di- and tri-unsaturated sterols are present in the extracts of fungi cultivated both in the dark and in the light but the sterol composition is different. The influence of “oat water” on sterol structure has been determined by comparison with the sterols of the same fungus grown on synthetic medium in the dark. 相似文献
7.
Using well-established techniques, samples were obtained of the volatile essential oils of the two types of curry leaf, Murraya koenigii and Pandanus latifolius. Both contained mainly terpenes, and M. koenigii produced less than 4% of other components with eight monoterpene hydrocarbons (ca 16%) and 17 sesquiterpene hydrocarbons (ca 80%) being obtained. The most important constituents of M. koenigii are β-caryophyllene, β-gurjunene, β-elemene, β-phellandrene and β-thujene. The volatile essential oil of P. latifolius also contained mainly sesquiterpene hydrocarbons (6–42%) but the only monoterpene was linalool (ca 6%). Nearly 2000 times the total quantity of aroma volatiles was produced by M. koenigii compared with P. latifolius, and this partly explains the observed stronger flavour potency of the former. 相似文献
8.
l-Arginine carboxy-lyase and l-ornithine carboxy-lyase activities were investigated in young decotylized Glycine max plants growing in the light on a liquid medium in the presence of ammonium chloride or nitrate. Only the first enzyme could be detected. It had pH optimum at 7.0 activity and there is much more activity in plants cultivated on ammonium chloride than in plants grown on nitrate. 相似文献
9.
R. Moreau 《Journal of insect physiology》1974,20(8):1475-1480
During the final stage of development the haemolymph of Lepidoptera does not seem to undergo great variations of pressure. At most, sudden rises of 10 to 15 mm Hg were noted during violent movements or at ecdysis.With an improved and very sensitive apparatus, a pressure eighteen times higher than the pressure measured normally was recorded. This sudden variation of blood pressure corresponds to the erectile stage of the extension of the wings. The study under different conditions has shown the importance of the part played by the abdominal muscles in the pressure of the haemolymph. 相似文献
10.
In Pachycerianthus fimbriatus McMurrich, collar cells have been found in the ectoderm layer of marginal and labial tentacles. Villi, nematocytes, spirocysts, two types of mucous gland cells, and trypsinogen gland cells have been described. We have failed to discover special apical structures linked with the uptake of ferritin in solution. The rôle of apical villi and collar cells is discussed. 相似文献
11.
Besides the known magnoflorine, four new protoberberines were isolated from leaves of Isopyrum thalictroïdes. Their structures were deduced from spectral data. The names pseudoberberine, pseudocoptisine, pseudocolumbamine and dehydropseudocheilanthifoline are proposed for them. 相似文献
12.
Josselyne Boulétreau-Merle 《Journal of insect physiology》1977,23(9):1099-1104
Fecundity and fertility of Drosophila females were studied after extirpation of one or two spermathecae. When extirpated females were mated only once, egg deposition was slightly accelerated but total egg production, during twelve days, was the same as in virgin operated females. Egg hatchability was high during two days but decreased more rapidly than in normal or sham-operated femalesWhen males were permanently kept with females, egg production and egg hatchability of operated females remained at a high level during the experiment. In that case, females could copulate frequently and the increase in egg production is interpreted as a consequence of paragonial fluid stimulationThe most significant rôle of spermathecae seems therefore to assume the transmission of the sperm stimulus to the brain; they probably also improve the survival capacities of sperm. 相似文献
13.
When grown on a synthetic medium containing Zn2+ and Cd2+ in toxic concentrations and a high concentration of Mg2+, the mycelium of Aspergillus niger ATCC 9029 is pigmented yellow. Four pigments have been chromatographically separated. Two are still unknown; the others are asperenone and asperrubrol. Asperrubrol is the methyl ester of a dimethyl 13-phenyl-3-ol-2,4,6,8,10,12-tridecahexaenoic acid. One of the methyl groups is on C2 and the other is probably at C8. Asperrubrol has been obtained as the enol of the all trans molecule; ketoe nolisation can be obtained by action of heat or alkalis. When grown on the same medium, 13 of 17 strains of A. niger produced asperrubrol and asperenone. 相似文献
14.
15.
Jean-François Gonnet 《Phytochemistry》1978,17(8):1319-1323
Nine infraspecific taxa of Anthyllis vulneraria have been investigated for leaf flavonoids. The distribution of 35 flavonol glycosides within 26 populations, indicated the presence of four chemical taxa, each based on different glycosides of 7-methylkaempferol. 相似文献
16.
The tissue localisation of flavonoids has been studied in leaves of Betula, Corylus, Fagus, Fraxinus, Pisum, Platanus, Quercus, Spinacia and Tilia and scales of onion bulbs. All these species contain flavonols which are, for the most part, located in the upper epidermis of the leaves. In the onion bulb, flavonols are exclusively in the epidermis. The flavonols are glycosylated and dissolved in the vacuoles. The leaves were fractionated by an original technique of abrasion of the frozen material. The physiological significance of such a distribution of flavonoids in the adult leaves or scales is discussed. 相似文献
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18.
Alanine 2-oxoglutarate aminotransferase, extracted by Triton X-100 from tomato mitochondria, has been purified and its main kinetic characteristics determined. This form is more unstable than the soluble enzyme. However, the chromatographic patterns, effect of pH on stability, the pH optimum, the specificity and the apparent molecular weight show that it is the same enzyme and not an isoenzyme. This identity is confirmed by the results of kinetic studies and by the inhibition data by the products of the reaction for the two forms. The kinetic results also show that the two forms reversibly catalyze the transamination reaction between alanine and 2-oxoglutarate according the Ping Pong mechanism described for the soluble enzyme. 相似文献
19.
J. Vercauteren J. Kerharo A.-M. Morfaux G. Massiot L. Le Men-Olivier J. Le Men 《Phytochemistry》1980,19(9):1959-1961
Nine known indole alkaloids were isolated from the stem and root barks of Hunteria elliotii: aspidofractinine, eburnamenine, eburnamine, isoeburnamine, eburnamonine, kopsinine, pleiocarpamine, quebrachamine and vincadifformine, along with o-ethyleburnamine. 相似文献
20.
Starved Cerianthus lloydi Gosse were fed experimentally with Crangon muscles ground and impregnated with Bromocresol Green powder. A phagocytosis of the muscular fibres was detected in the cells of the endoderm layer of the sterile septa. In addition, through feeding with chicken blood, a phagocytosis became evident in the endoderm of sterile septa and of tentacles.The use of Ferritin allowed us to prove an uptake in all the endoderm cells of Cerianthus lloydi with an intensity which varies from one tissue to another. Furthermore, there is an unexpected pinocytosis in the ectoderm layer of the peristome, of pharynx, and the labial tentacles.Results obtained with bacteria and labelled amino acids are less conclusive. Perhaps the techniques used were inadequate. 相似文献