This research was aimed to determine the hydrophilic bioactive extractives of Arizona cypress. The extractives of Arizona cypress were isolated and characterized by gas chromatography-mass ...spectrometry (GC-MS). Hydrophilic compounds of the extractives were mildly isolated by soaking the wood flour in ethanol: water (9:1 v/v) solution followed by n-hexane extraction to remove the lipophilic moieties. Raw extract of Arizona cypress was further purified to isolate the bioactive phenols using dichloromethane-ethanol in a solvent-solvent system and precipitation with potassium acetate. The bioactivity of the hydrophilic extracts of Cupressus arizonica was determined and compared with the raw hydrophilic extractives of Cupressus sempervirens and Picea excelsa. The total phenol content was determined according to the folin-ciocalteu method. The antioxidant capacity was determined by iron (II) chelating activity and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. From the GC/MS analysis, different amounts of bioactive moieties, including matairesinol (MAT), curcumin, dienestrol, arctigenin (ARC) and sescoisolariciresinol (SEC), were found in the extract of C. arizonica wood knots. Comparative evaluation of the total phenolics by folin-ciocalteu analysis showed that extraction by simple soaking could precisely indicate the quantity of phenolic compounds in the extracts. The antioxidant activity of extracts indicated by DPPH radical scavenging and iron (II) chelating capacity showed that the antioxidant activity is dependent on the amount and category of bioactive phenols in the extracts.
Antibacterial activity of essential oil of Picea excelsa was tested with the dilution method against one strain of Listeria ivanovii, six of L. monocytogenes, three of Staphylococcus aureus, three of ...Escherichia coli, one of Klebsiella oxytoca, one of K. pneumoniae subsp. pneumoniae and one of Enterobacter cloacae. For Gram-positive bacteria in stationary phase, 0·07% of essential oil inhibited about 105colony forming unit per ml; a dose of 0·2–0·3% was bactericidal for 105–107cells contained in 1 ml of liquid culture at 37°C. The coliforms, at a concentration of 105CFU per ml, are resistant whatever the physiological age, since they grow with 8% of essential oil. A simplified technique gives good results for the determination of bactericidal activity against Listeria, only indication against S. aureus.
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Ectomycorrhizas of four‐year‐old Picea excelsa (Lam.) Link seedlings, grown in nursery soil, are described. The main ectomycorrhiza type, occurring on 55–80% of the root apices, exhibited a ...normal sheath. The associated symbiotic fungus probably belonged to the Hebeloma genus. Behind these extomycorrhizal root lips, older ectomycorrhizas were observed and the apical ones presumably originated from those. One‐ and two‐year‐old ectomycorrhizas lacked sheaths, but a normal Hartig net could be observed in transverse sections. The metabolic‐activity of these older ectomycorrhizas, as measured by radiorespirometry of 14Cglucose, was reduced compared to the younger symbiotic organs. This glucose respiration was, however, still larger than the activity of non‐mycorrhizal exploratory roots. The mechanism of sheath loss and its significance as an ageing process are discussed.
The ammonia assimilation enzyme glutamate dehydrogenase was studied in extracts of spruce (Picea excelsa L.) roots, mycelium of a mycorrhizal fungus (Hebeloma sp.) and associated ectomycorrhizas. ...Evidence from enzyme reactions in crude extracts, electrophoretic patterns and immunological tests using antibodies raised against purified NADP-GDH of Cenococcum geophilum Fr. consistently showed that Hebeloma NADP-dependent GDH was active in spruce ectomycorrhizas. Histochemical studies associated some NADP-GDH activity with the Hartig net. By contrast, the NADP-GDH fungal pathway was strongly suppressed in beech (Fagus sylvatica L.) associations with Hebeloma crustuliniforme (Bull. ex St Amans) Quel. and Paxillus involutus (Batsch ex Fr.) Fr.
Cultured cells of Picea excelsa capable of forming stilbenes and flavanoids have been established. Unlike needles of intact plants containing piceatannol (3,3′,4′,5-tetrahydroxystilbene) and stilbene ...glycosides the cultured cells converted phenylalanine and p-coumaric acid primarily into resveratrol monomethyl ether (3,4′-dihydroxy-5-methoxystilbene) and naringenin. Partially purified enzyme preparations were assayed for chalcone synthase as well as for stilbene synthase activity converting malonyl-CoA plus p-coumaroyl-CoA into 3,4′,5-trihydroxystilbene (resveratrol). Although stilbene synthase and chalcone synthase use the same substrates and exhibit similar molecular properties, i.e. molecular weight and subunit molecular weight, they are two different proteins. This difference was demonstrated by gel electrophoresis and by means of monospecific antibodies.
L'épicéa commun (1-4)
Le sapin pectiné (5-9)
1. Rameau feuillu avec cône à maturité (gr. 2/3), pendant.
2. Chatons mâles (gr. 2/5).
3. Fleurs femelles (gr. 2/5).
4. Face interne d'une écaille et ...graines ailées (gr. 4/5).
5. Rameau feuillu avec cône dressé (gr. 2/3).
6. Chatons mâles (gr. 2/5).
7. Rameau de l'année avec fleurs femelles.
8. Détails d'une écaille avec la bractée saillante (gr. 2/3).
9. Face interne d'une écaille et graines ailées (gr. 2/3).
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