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1.
Environ Monit Assess ; 75(2): 201-13, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12002287

RESUMEN

The use of bioindicators for contaminant monitoring is popular in all sectors of the environment but quite often bioindicators are utilised without rigorous evaluation of their viability as an indicator. We report field and laboratory investigations into the value of a commonly found macroalga, Enteromorpha flexuosa (Wulfen) J. Agardh (Chlorophyta: Ulvales) as an indicator of copper, zinc and lead contamination in a tropical estuary in Fiji. In the laboratory, metal content of E. flexuosa after 60 days of growth in seawater containing increasing concentrations of the metals showed almost perfect correlation with metal concentrations in water for all three metals, and concentration factors obtained were generally higher than values reported for other species of Enteromorpha. Performance in the field was evaluated by a one-year monitoring of metals in E. flexuosa, water and sediments from a contaminated estuary. Metal concentrations in water were always below detection limits and field concentration factors could not be determined but the concentration of lead in E. flexuosa showed a high correlation with the lead content of sediments. Lack of such correlation for copper and zinc in the field suggests that other environmental factors besides metal load in the physical environment could be controlling the bioaccumulation of these two metals. Whilst demonstrating E. flexuosa to be a viable bioindicator for lead, these results also highlight the need for proper assessment before an organism is considered for environmental monitoring.


Asunto(s)
Chlorophyta/química , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Metales Pesados/farmacocinética , Contaminantes del Agua/análisis , Contaminantes del Agua/farmacocinética , Ecosistema , Fiji , Sensibilidad y Especificidad , Clima Tropical
2.
Phytochemistry ; 53(2): 281-4, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10680184

RESUMEN

Four biogenetically related benzophenones have been isolated from the Fijian Garcinia pseudoguttifera. They are: 6-hydroxy-2,4-dimethoxy-3,5-bis(3-methyl-2-butenyl)benzophenone (myrtiaphenone-A); 2,2-dimethyl-8-benzoyl-7-hydroxy-5-methoxy-6-(3-methyl-2-butenyl)benzopy ran (myrtiaphenone-B); 2,6-dihydroxy-4-methoxy-3,5-bis(3-methyl-2-butenyl)benzophenone (vismiaphenone-C) and a new benzophenone, 2,2-dimethyl-8-benzoyl-3,7-dihydroxy-5-methoxy- 6-(3-methyl-2-butenyl)-3,4-dihydrobenzopyran (pseudoguttiaphenone-A). Pseudoguttiaphenone-A could be biogenetically derived from vismiaphenone-C. The major component of G. pseudoguttifera was identified as eupha-8,24-dien-3 beta-ol.


Asunto(s)
Benzofenonas/química , Plantas Medicinales/química , Benzofenonas/aislamiento & purificación , Fiji , Conformación Molecular , Estructura Molecular
3.
Bioorg Med Chem Lett ; 8(24): 3475-8, 1998 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-9934455

RESUMEN

The seeds of Calophyllum cerasiferum Vesque (Family-Clusiaceae), and Calophyllum inophyllum Linn. (Family-Clusiaceae) contain several known coumarins, among which were the potent HIV reverse transcriptase inhibitors costatolide and inophyllum P. Calophyllum cerasiferum contained (-)-calanolide B as its major coumarin constituent in significant amount and thus constitute a renewable source of this compound.


Asunto(s)
Fármacos Anti-VIH/aislamiento & purificación , Cumarinas/aislamiento & purificación , Inhibidores de la Transcriptasa Inversa/aislamiento & purificación , Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacología , Cumarinas/química , Cumarinas/farmacología , Estructura Molecular , Inhibidores de la Transcriptasa Inversa/química , Inhibidores de la Transcriptasa Inversa/farmacología
4.
Planta Med ; 56(3): 290-2, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17221421

RESUMEN

The pentacyclic triterpenoids serjanic acid and phytolaccagenic acid as well as a new glycoside, 3- O-beta- D-glucopyranosylphytolaccagenic acid have been isolated from the stem of DIPLOCLISIA GLAUCESCENS (Bl.) Diels (Menispermaceae). New spectroscopic data are furnished for serjanic acid and phytolaccagenic acid.

7.
Steroids ; 49(4-5): 397-402, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3455051

RESUMEN

The chemical synthesis and physical data of several new esters of testosterone (17 beta-hydroxyandrost-4-en-3-one), which contain either a halogeno or an alkoxy substituent in the acid chain, are reported.


Asunto(s)
Anticonceptivos Masculinos/síntesis química , Testosterona/análogos & derivados , Ácidos Carboxílicos , Fenómenos Químicos , Química , Testosterona/farmacología
8.
Steroids ; 46(6): 947-53, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3842023

RESUMEN

The synthesis of ten esters and two ethers of testosterone (17 beta-hydroxyandrost-4-en-3-one) is described. All these possess some form of alpha - and/or beta - substitution in the ester/ether side-chain. The work was undertaken in order to evaluate the long-acting antifertility effect of such compounds in males.


Asunto(s)
Anticonceptivos Masculinos/síntesis química , Testosterona/análogos & derivados , Fenómenos Químicos , Química , Ésteres , Éteres , Testosterona/síntesis química
9.
Steroids ; 41(3): 285-90, 1983 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6658876

RESUMEN

The chemical synthesis and physical data of several new esters of norethisterone (17 alpha-ethynyl-17 beta-hydroxyestr-4-en-3-one) are reported, which contain either a chloro- or an alkoxy-group as a substituent in the acid side-chain.


Asunto(s)
Noretindrona/análogos & derivados , Ácidos Carboxílicos , Preparaciones de Acción Retardada , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Noretindrona/síntesis química , Espectrofotometría Infrarroja , Relación Estructura-Actividad
11.
Planta Med ; 43(11): 309-10, 1981 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17402053
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