La systématique infraspécifiquede l'Anthyllis vulneraria (Leguminosae) vue à la lumière de la biochimie flavonique

Twenty-six experimental populations of A. vulneraria were surveyed for leaf flavonoids. The distribution of 34 flavonol glycosides showed, after factor analysis, the existence of for distinct chemical taxa, each exhibiting characteristic glycosides of 7-methylkaempferol. These results, and others obtained from further factor analysis, are discussed in relation to Couderc's taxonomic studies, and allow a better definition of infraspecific units of A. vulneraria. Flavonoid and morphological data are generally correlated.     

A comparative study of the flavonoids of Medicago radiata with other Medicago and related Trigonella species

The flavonoid glycosides of Medicago radiata as well as M. arabica, M. polymorpha, M. sativa, Trigonella coerulescens, T. foenum-graecum and T. spicata were studied in detail. Major glycosides identified were the 7-glucuronides of apigenin, luteolin, chrysoeriol and tricin, as well as lesser amounts of di- and triglucuronides of chrysoeriol and tricin. Also identified were the 3-robinobioside and 3,7-diglucoside of kaempferol, along with lesser amounts of quercetin-3,7-diglucoside, 4′,7-dihydroxyflavone, 3′,4′,7-trihydroxyflavone, formononetin and daidzein. Twelve other Medicago and Trigonella species were also studied for their flavonoid aglycones. The systematic position of M. radiata is discussed.     

Flavonoid glycosides of Tribulus pentandrus and T. Terrestris

Twenty-five flavonoid glycosides were detected in Tribulus pentandrus and T. terrestris. The glycosides belong to the common flavonols, kaempferol, quercetin and isorhamnetin, with the 3-gentiobiosides as the major glycosides. Traces of a flavone (tricin) glycoside was also present in T. pentandrus. The separation of Tribulaceae as a distinct family from Zygophyllaceae is discussed.     

Etude de l'activite de l'arginine decarboxylase dans les jeunes plantes de Glycine max privees de leurs cotyledons

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.     

Flavonoid glycosides and the chemosystematics of Eucalyptus camaldulensisis

Leaf flavonoid glycosides of Eucalyptus camaldulensis were identified as kaempferol 3-glucoside and 3-glucuronide; quercetin 3-glucoside, 3-glucuronide, 3-rhamnoside, 3-rutinoside and 7-glucoside, apigenin 7-glucuronide and luteolin 7-glucoside and 7-glucuronide. Two chemical races were observed based on the flavonoid glycosides. These races correspond to the northern and southern populations of species growing in Australia. The Middle Eastern species examined were found to belong to the southern Australian chemical race. The major glycosides of E. occidentalis proved to be quercetin and myricetin 3-glucuronide.     

Action de l'hormone juvenile et de certains mimetiques sur l'epithelium intestinal chez Galleria mellonella

We have investigated the influence of juvenile hormone (JH) on the intestinal epithelium of G. mellonella, in vivo and in vitro. The larvae undergoing a supernumerary instar present a typical larval epithelium with columnar (CL) and globlet (CF) cells; the spinning period is characterized by a delay and a loss of synchronism in the process of differentiation of intermediates cells (Ci) typical of the pharate pupa. The larval-pupal intermediates show true mosaïcs in which Ci and CF are juxtaposed; however, the ratio of Ci in the epithelium progressively increases.The injection of JH at the beginning of spinning induces the appearance of CF just as Ci should normally grow. Hormone administration during the second half of the spinning period modifies the differentiation of epithelial cells: they become taller. We consider them to be cells engaged in pharate pupal differentiation, and which have then been partially oriented toward larval differentiation.These results show that the intestinal epithelium is a competent tissue, the sensibility of which to JH, is higher than that of the epidermis. The basal cell plasticity is very important and the action of JH on their differentiation may lead to CL or CF, to tall cells, and to Ci, depending on hormonal rate. In vitro, the experiments show that the action of JH is probably direct on the target tissue. The fact that JH can act very late as a modifier of the differentiation of the growing epithelial cells exclude the possibility that the hormone exercises its control through DNA replication.     

La diamine oxydase dans les jeunes plantes de Glycine max

Diamine oxidase activity against putrescine and agmatine is investigated in young decotylized Glycine max plants growing, in the light, under sterile conditions on a liquid medium in the presence of ammonium chloride or nitrates. Optimal conditions for the enzyme activity are determined. Both amines are oxidised more slowly in plants cultivated on ammonium chloride than in plants grown on nitrates.     

Chromanones de l'écorce de Calophyllum recedens

Three new compounds, recedensolide Ia, recedensic acid IIa and isocalolongic acid IIIa, have been isolated from Calophyllum recedens bark (Gutt     

Origine et caracteres de la sécrétion d'aglycones flavonoliques par les bourgeons d'Aesculus hippocastanum

Flavonol aglycones are present in the oil excreted by buds of Aesculus hippocastanuml. and are probably synthesized in glandular hairs situated on the inner side of bud scales. Flavonols are most abundant in the hairs, being much less concentrated in all other scale tissues. Flavonol accumulation in the buds reaches a maximum both in the Spring and the Autumn and this is related to the accumulation of leaf flavonols and leucoanthocyanes and of scale and bark coumarins.     

Les sterols de l'Ascomycete Leptosphaeria typhae

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.     

Modifications de l'équipement endocrine et morphogenèse génitale chez l'embryon de Carausius

It has previously been shown that in Carausius the mechanisms ensuring normal, i.e. female, differentiation of the genital rudiment can be deflected towards male differentiation. A study of bicephalic monsters and microsurgical experiments show that the genital anlage is not affected by a lack or an excess of neurosecretory or allatal components. However, experiments show that the prothoracic glands (=ventral cephalic glands) play an important part in the development of the genital anlage.     

Isoflavan phytoalexins from Anthyllis,lotus and Tetragonolobus

Two previously unreported phytoalexins, 7,4′dihydroxy-2′-methoxy- and 7,2′,4′-trihydroxyisoflavan, have been isolated from the fungus-inoculated leaves of Anthyllis vulneraria and 5 Tetragonolobus species. Examination of Lotus corniculatus revealed the co-occurrence of the latter with the known isoflavans, vestitol and sativan. Only 7,2′4′-trihydroxyisoflavan and vestitol were produced by the closely related L. uliginosus.     

Variations de la pression interne au cours de l'émergence et de l'expansion des ailes chez Bombyx mori et Pieris brassicae

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.     

Fonction chromatrope de la pars intercerebralis chez l'acridien Oedipoda coerulescens

The median neurosecretory cells of the protocerebrum of fifth instar larvae and 1- or 2-day-old adults of Oedipoda coerulescens produced more fuchsinophilic material when reared on dark backgrounds than on pale ones. In the latter case, the neurosecretory cell bodies were almost completely devoid of neurosecretion. The same differences were found in the anterior lobes of the corpora cardiaca. Individuals implanted with pars intercerebralis from donors reared on a dark background showed dark pigmentation no matter what their own background colour (and conversely). Black or red pigmentation appeared on absorbent grounds whereas a pale one was produced on reflecting grounds with high levels of incident light predominantly between 576 and 588 mμ. The significance of these results is discussed. A possible scheme for the interaction of environmental factors and pigmentation is suggested.     

2,5-Dihydroxymethyl 3,4-dihydroxypyrrolidine dans les feuilles de Derris elliptica

A new natural imino-alcohol, 2,5-dihydroxymethyl 3,4-dihydroxypyrrolidine has been isolated from the leaves of Derris elliptica. Its structure was determined by chemical and physical methods.     

Les relations entre les prairies du Triseto-Polygonion et les mégaphorbiaies de l''Adenostylion: l''analyse flavonique d''espèces communes aux deux groupements

Relationships between two plant communities in the south-western Alps, high-altitude manured meadows (Triseto-Polygonion) and lower tall grass prairies (Adenostylion) have been examined by means of the flavonoid analysis of specimens belonging to six species common to those two associations. The species, collected at eight stations of the Ligurian Alps and the Ubaye valley, are: Trollius europaeus (Ranunculaceae), Chaerophyllum aureum (Umbellifereae), Silene cucubalus (Caryophyllaceae), Polygonum bistorta) (Polygonaceae), Alchemilla vulgaris (Rosaceae) and Centaurea montana (Compositae). In every species, factorial analysis of correspondence was applied to the distribution of flavonoid glycosides. This led to the partition of the populations into two groups according to the two sectors (Ligurian Alphs Ubaye valley) of the collection area. Secondly, populations of two species, Alchemilla vulgaris and Centaurea montana, exhibited further correlation of their flavonoid pattern with their phytosociological origin.     

Role des spermatheques dans l'utilisation du sperme et la stimulation de l'ovogenese chez Drosophila melanogaster

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.     

Identification des constituants de l'essence des aiguilles de Pinus pinaster

The chromatographic analysis of the volatile leaf oil of Pinus pinaster Ait. showed 42% of monoterpene hydrocarbons (α-pinene, camphene, β-pinene, myrcene, 3-carene, limonene, cis-ocimene, terpinolene, para-cymene, 35% of sesquiterpene hydrocarbons (cubebene, copaene, caryophyllene, humulene, germacrene D, α- and γ-muurolenes, δ- and γ-cadinenes) and 23% of oxygenated compounds including esters (linalyl, bornyl, geranyl, neryl and farnesyl acetates), alcohols (cis-hexenol, linalool, α-fenchol, trans-pinocarveol, terpinen-4-ol, α-terpineol, dihydrocarveol, guaiol, junenol and α-cadinol), one aldehyde (hexenal) and one ketone (piperitone). Three non terpenoid phenylethyl esters were also identified: phenylethyl isovalerate, methyl-2 burtyate and 3-3 dimethylacrylate. Some alcohols and mainly α-terpineol and linalool seemed to be formed during the steam distillation process, they were absent when the leaf oil was obtained by maceration of small portions of leaves in the usual solvents of terpenes.