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1.
Nat Prod Commun ; 8(2): 257-60, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23513743

RESUMO

Essential oils obtained by hydrodistillation of female cones (FC), male cones (MC), needle-twigs (NT) and wood-bark (WB) of 'Carolina Sapphire' [Cupressus arizonica var glabra (Sudw.) Little] were analyzed simultaneously by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). The main constituents of the investigated essential oils were as follows: FC: alpha-pinene 68.5% and myrcene 11.9%; MC: alpha-pinene 22.5%, epi-zonarene 9.9%, zonarene 6.9%, limonene 6.8% and cadina-3,5-diene 6.1%; NT: alpha-pinene 20.7%, epi-zonarene 10.4%, zonarene 7.6%, limonene 5.9% umbellulone 5.8% and cadina-3,5-diene 5.8%; WB: alpha-pinene 40.7%, limonene 3.2% and umbellulone 2.9%. Essential oils were evaluated for antifungal activity against the strawberry anthracnose causing fungal plant pathogens Colletotrichum acutatum, C. fragariae and C. gloeosporioides. Only WB essential oil showed moderate activity when compared with the commercial antifungal standards. Carolina Sapphire essential oils exhibited biting deterrent activity at 10 microg/cm2 with Biting Deterrence Index (BDI) values of 0.64, 0.59, 0.65 and 0.72, for FC, MC, NT and WB, respectively, and were significantly lower (P < or = 0.05) than the synthetic insect repellent, DEET (N,N-diethyl-meta-toluamide), at 25 nmol/cm2 against Aedes aegypti. The biting deterrence of NT and WB oils at 100 microg/cm2 with BDI values of 1.04 and 1.01, respectively, were similar, whereas the activity of MC (BDI = 0.88) and FC (BDI = 0.62) essential oils was lower than DEET at 25 nmol/cm2. Essential oil from FC with LD50 of 33.7 ppm was most toxic against 1-day-old Ae. aegypti larvae at 24-h post treatment. Female cone essential oil was significantly more toxic than MC (LD50 = 53.6 ppm), NT (LD50 = 55.5 ppm) and WB (LD50 = 44.6 ppm) essential oils.


Assuntos
Antifúngicos/farmacologia , Cupressus/química , Inseticidas/farmacologia , Óleos Voláteis/farmacologia , Aedes , Animais , Cupressus/anatomia & histologia , Larva/efeitos dos fármacos
2.
Bioresour Technol ; 101(24): 9500-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20727738

RESUMO

The feasibility of using cypress cone chips from Cupressus sempervirens as a low-cost biosorbent for the removal of two representative basic dyes, methylene blue (MB) and rhodamine B (RhB), from aqueous solutions was investigated in batch and continuous modes. Dyes biosorption was strongly dependent on the solution's pH. Sorption kinetics was determined and properly described by the pseudo-second-order rate model. Experimental equilibrium isotherms fitted the Langmuir model, showing maximum biosorption capacities of 0.62 mmol/g for MB and 0.24 mmol/g for RhB. Competitive experiments from a binary solution of the dyes demonstrated the preference of the cone chips for biosorbing MB. Very low desorption efficiencies were obtained for both dyes. Dynamic experiments showed that the breakthrough time was three times higher for MB biosorption than for RhB for the same conditions. Breakthrough curves were properly represented by a mathematical model.


Assuntos
Corantes/isolamento & purificação , Cupressus/anatomia & histologia , Cupressus/metabolismo , Purificação da Água/métodos , Adsorção , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Cinética , Azul de Metileno/isolamento & purificação , Modelos Químicos , Rodaminas/isolamento & purificação , Soluções , Temperatura
3.
Pak J Biol Sci ; 10(20): 3734-7, 2007 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19093493

RESUMO

Zarbin (Cupressus sempervirence var. horizontalis) with its unique characteristics is one of the worthiest species which can be found in the central area of Alborz in the North of Iran. Especially in the Roodbar-manjil area, Chaloos-Hassanabad valley as well as it extends from Zarringol area to Gorgan. Although the distribution areas of this species have been protected, these forests have been invaded by the villagers who use this useful wood. For this reason in the Roodbar area, trees with DBH>30 cm are extremely rare. To recognize and to be aware of the stand quantity, the current research tries to calculate the species volume table in Roodbar area, to be the basis for any calculation of the volume of stand in the region. For this purpose, trees have been sampled using the line sampling method. After estimating the form factor, Tarif table have been prepared. In this study, a new method for measuring tree height is presented, in which, instead of measuring slope distance from observer to tree (which is difficult in young conifers because of existence branches in lower height) distance between the eye level of observer to tree butt is measured. Which doing of it is easier, time of field work is decreased and accuracy of measurement and calculation is increased.


Assuntos
Cupressus/anatomia & histologia , Agricultura Florestal/métodos , Árvores/anatomia & histologia , Ecossistema , Irã (Geográfico) , Pesos e Medidas
4.
J Theor Biol ; 227(1): 137-47, 2004 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-14969712

RESUMO

This paper presents a general mathematical model for the morphometric description of trees. This model is based on the introduction of fractal theory, and more particularly of the concept of self-similarity, into a statistical physics rationale. Fractal theory provides the necessary tools to describe the complexity of tree structure. Statistics, when applied to physics, makes it possible to explain the properties of complex objects starting from their components. The combination of both tools allowed us to develop a theoretical model that is the probability density function of the morphometric lengths of trees. An example of validation of this law is given here: the theoretical model of morphometric lengths is compared with experimental data of Cupressocyparis.


Assuntos
Modelos Biológicos , Árvores/anatomia & histologia , Cupressus/anatomia & histologia , Fractais , Reprodutibilidade dos Testes
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